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Sample records for chick embryo limb

  1. A Chick Embryo in-Vitro Model of Knee Morphogenesis

    PubMed Central

    Rodriguez, Edward K.; Munasinghe, Jeeva

    2016-01-01

    Background: In this feasibility study, a mechanically loaded in-vitro tissue culture model of joint morphogenesis using the isolated lower extremity of the 8 day old chick embryo was developed to assess the effects of mechanical loading on joint morphogenesis. Methods: The developed in-vitro system allows controlled flexion and extension of the chick embryonic knee with a range of motion of 20 degrees from a resting position of 90-100 degrees of flexion. Joint morphogenesis at 2, 3, 4 and 7 days of culture was assessed by histology and micro MRI in 4 specimen types: undisturbed in-ovo control embryos, in-ovo paralyzed embryos, in-vitro unloaded limb cultures, and in-vitro loaded limb cultures. Relative glycosaminoglycan (GAG) concentration across the joint was assessed with an MRI technique referred to as dGEMRIC (delayed gadolinium enhanced MRI of cartilage) where T1 is proportional to glycosaminoglycan concentration. Results: Average T1 over the entire tissue image for the normal control (IC) knee was 480 msec; for the 4 day loaded specimen average T1 was 354 msec; and for the 7 day loaded specimens T1 was 393 msec. The 4 day unloaded specimen had an average T1 of 279 msec while the 7 day unloaded specimen had an average T1 of 224 msec. The higher T1 values in loaded than unloaded specimens suggest that more glycosaminoglycan is produced in the loaded culture than in the unloaded preparation. Conclusion: Isolated limb tissue cultures under flexion-extension load can be viable and exhibit more progression of joint differentiation and glycosaminoglycan production than similarly cultured but unloaded specimens. However, when compared with controls consisting of intact undisturbed embryos in-ovo, the isolated loaded limbs in culture do not demonstrate equivalent amounts of absolute growth or joint differentiation. PMID:27200386

  2. Microwave effects on isolated chick embryo hearts

    SciTech Connect

    Caddemi, A.; Tamburello, C.C.; Zanforlin, L.; Torregrossa, M.V.

    1986-01-01

    This study was designed to examine the effects of microwaves on the electric activity of hearts as a means of elucidating interactive mechanisms of nonionizing radiation with cardiac tissue. Experiments were performed on isolated hearts of 9-12-day-old chick embryos placed in small petri dishes. Oxygenated isotonic Ringer's solution at 37 degrees C permitted heart survival. Samples were irradiated at 2.45 GHz with a power density of 3 mW/cm2. The heart signal was detected with a glass micropipet inserted into the sinoatrial node and examined by means of a Berg-Fourier analyzer. Pulsed microwaves caused the locking of the heartbeat to the modulation frequency, whereas continuous wave irradiation might have induced slight bradycardia. Pulsed fields induced stimulation or regularization of the heartbeat in arrhythmia, fibrillation, or arrest of the heart.

  3. Studies on type C influenza virus in the chick embryo.

    PubMed

    Jennings, R; Freeman, M J

    1972-03-01

    The effect of varying conditions of inoculation and incubation on the growth of type C influenza virus in the allantoic cavity of the developing chick embryo were investigated. It was found that the highest yields of both virus haemagglutinin and infectious virus were obtained following the inoculation of chick embryos at 8 days with subsequent incubation at 32 degrees C. Using the chick embryo allantoic cavity for titration of infectious virus, growth curves of allantoically propagated virus under varying inoculation and incubation conditions were determined.

  4. Gap junction signalling mediated through connexin-43 is required for chick limb development.

    PubMed

    Makarenkova, H; Patel, K

    1999-03-15

    During chick limb development the gap junction protein Connexin-43 (Cx43) is expressed in discrete spatially restricted domains in the apical ectodermal ridge (AER) and mesenchyme of the zone of polarising activity. Antisense oligonucleotides (ODNs) were used to investigate the role of Connexin-43 (Cx43) in the development of the chick limb bud. We have used unmodified ODNs in Pluronic F-127 gel, which is liquid at low temperature but sets at room temperature and so remains situated at the point of application. As a mild surfactant, the gel increases antisense ODN penetration and supplies ODNs to the embryo continually for 12-18 h. We have shown a strong decrease in Cx43 protein expression after application of specific antisense oligonucleotides but the abundance of a closely related protein, Connexin-32 (Cx32), was not affected. Application of antisense Cx43 ODNs at stages 8-15 HH before limb outgrowth resulted in dramatic limb phenotypes. About 40% of treated embryos exhibited defects such as truncation of the limb bud, fragmentation into two or more domains, or complete splitting of the limb bud into two or three branches. Molecular analysis of antisense treated embryos failed to detect Shh or Bmp-2 in anterior structures and suggested that extra lobes seen in nicked and split limbs were not a result of establishment of new signalling centres as found after the application of FGF to the flank. However, examination of markers for the AER showed a number of abnormalities. In severely truncated specimens we were unable to detect the expression of either Fgf-4 or Fgf-8. In both nicked and split limbs the expression of these genes was discontinuous. Down-regulation of Cx43 after the antisense application could be comparable to AER removal and results in distal truncation of the limb bud. Taken together these data suggest the existence of a feedback loop between the FGFs and signalling mediated by Cx43.

  5. Use of the Chick Embryo Model in Uveal Melanoma.

    PubMed

    Kalirai, Helen; Shahidipour, Haleh; Coupland, Sarah E; Luyten, Gregorius

    2015-04-01

    Animal models play a crucial role in basic and translational oncology research. Conventional rodent experiments, however, face ethical, practical and technical issues that limit their use. The chick embryo represents an accessible and economical in vivo model, which has long been used in developmental biology and for the study of angiogenesis. It is also a recognised xenograft model, and because of its lack of immune system in early development, the chick embryo has established itself as a key model system for cancer research, with which to study various steps in the metastatic process. In this chapter, we review the chick embryo model and the technical approaches adopted by cancer biologists, including advances in real-time imaging, and discuss how this has been or can be applied to improve our understanding of the biological events during uveal melanoma development and metastasis.

  6. Ex Ovo Model for Directly Visualizing Chick Embryo Development

    ERIC Educational Resources Information Center

    Dorrell, Michael I.; Marcacci, Michael; Bravo, Stephen; Kurz, Troy; Tremblay, Jacob; Rusing, Jack C.

    2012-01-01

    We describe a technique for removing and growing chick embryos in culture that utilizes relatively inexpensive materials and requires little space. It can be readily performed in class by university, high school, or junior high students, and teachers of any grade level should be able to set it up for their students. Students will be able to…

  7. Electron microscopy of Lednice virus in chick embryo cells.

    PubMed

    Jelínková, A; Málková, D; Holubová, J; Novák, M

    1980-01-01

    Replication of Lednice virus in chick embryo cells was studied for 72 hr after inoculation by infectivity titration and the indirect immunofluorescence technique. At 24 and 48 hr after inoculation, electron microscopy revealed spherical virions of uniform morphology, 80-105 nm in diameter, which were localized mostly extracellularly.

  8. Isolation of herpes simplex viruses by chick embryo culture.

    PubMed

    Akter, T; Tabassum, S; Jahan, M; Nessa, A; Islam, M N; Giasuddin, M

    2013-04-01

    The chick embryo is a versatile host system in diagnostic virology, especially for isolation of herpes simplex viruses. In this study, samples obtained from 57 clinically diagnosed patients with active herpetic lesions (35 genital & 22 non-genital) were cultured by chick embryo method for isolation of herpes simplex virus. After inoculation onto the chorioallantoic membrane (CAM) of 10-11 days old chick embryo, typical CAM reactions (pocks) appeared in 23(40.3%) samples after 3 days. CAM reactions were identified and typed by direct fluorescence antibody test and 22(95.6%) of 23 isolates gave positive results. Of this, 9(40.9%) were HSV-1 & 13(59.1%) were HSV-2. HSV-1 was isolated from 8(36.4%) of non-genital samples and from 1(7.1%) genital sample. HSV-2 was isolated from 13(92.8%) of genital samples, but none were isolated from non-genital samples. High isolation rate was obtained from vesicular stage of both non-genital (71.5%) and genital (57.1%) samples and from early lesions (sampled within 72 hours) of non-genital (50%) and genital (52.9%) specimen. The chorioallantoic membrane of chick embryo it is a simple, cheap and efficient method of cultivation of some viruses, including HSV. Thus, in settings where cell culture facilities are not available, it can be used for the isolation of herpes simplex viruses from clinical samples.

  9. Culturing Chick Embryos--A Simplification of New's Method.

    ERIC Educational Resources Information Center

    Downie, J. R.

    1979-01-01

    Describes a simplified version of New's method for culturing early chick embryos. The technique allows continuous observation of the critical first three days of development and the conditions for setting up successful cultures are also presented to help both teachers and students. (HM)

  10. Specific factors influencing histotypic aggregation of chick embryo hepatocytes.

    PubMed Central

    Sankaran, L; Proffitt, R T; Petersen, J R; Pogell, B M

    1977-01-01

    Conditions are described for the reproducible assay of substances affecting the in vitro rate of aggregation of isolated chick embryo hepatocytes. Two low molecular weight (less than 1000) fractions--one that promotes hepatocyte aggregation (HAP) and the other that inhibits this stimulation (HAI)--have been isolated and partially purified from adult chicken liver. One major active component of HAP was identified as taurine (2-aminoethanesulfonate). The presence of HAP during the entire time of assay was required for largest aggregate formation. HAP had no effect on aggregation of chick embryo neural retina, kidney, or heart cells. Our results and the fact that puromycin completely inhibits aggregate formation suggest that HAP and HAI influence the specific synthesis and interaction of membrane macromolecules involved in the aggregation process. Images PMID:270696

  11. Titration of vaccinia virus by intravenous injection of chick embryos.

    PubMed

    KAPLAN, C

    1960-01-01

    The final test of a smallpox vaccine is its capacity to prevent the disease from developing in inoculated individuals. This capacity, however, cannot be measured directly, so that other methods of assessing the efficacy of vaccine have had to be developed. A laboratory method-pock counting on the chorio-allantoic membrane of chick embryos-has recently been shown to provide a reasonably reliable estimate of the number of infective units in a given vaccine. In this paper, the author compares this pock-counting method with another method-titration by intravenous injection of chick embryos. He concludes that, although the reproducibility of titrations by intravenous injection compares very favourably with that obtained by chorio-allantoic inoculation, the former method would not be advantageous for the assay of vaccines, since it is very time-consuming and since differences in virulence might obscure comparisons between the efficacy of vaccines.

  12. A cellular lineage analysis of the chick limb bud

    PubMed Central

    Pearse, R.V.; Scherz, P. J.; Campbell, J. K.; Tabin, C. J.

    2009-01-01

    The chick limb bud has been used as a model system for studying pattern formation and tissue development for more than 50 years. However, the lineal relationships among the different cell types and the migrational boundaries of individual cells within the limb mesenchyme have not been explored. We have used a retroviral lineage analysis system to track the fate of single limb bud mesenchymal cells at different times in early limb development. We find that progenitor cells labeled at stage 19–22 can give rise to multiple cell types including clones containing cells of all five of the major lateral plate mesoderm-derived tissues (cartilage, perichondrium, tendon, muscle connective tissue, and dermis). There is a bias, however, such that clones are more likely to contain the cell types of spatially adjacent tissues such as cartilage/perichondrium and tendon/muscle connective tissue. It has been recently proposed that distinct proximodistal segments are established early in limb development; however our analysis suggests that there is not a strict barrier to cellular migration along the proximodistal axis in the early stage 19–22 limb buds. Finally, our data indicate the presence of a dorsal/ventral boundary established by stage 16 that is inhibitory to cellular mixing. This boundary is demarcated by the expression of the LIM-homeodomain factor lmx1b. PMID:17888899

  13. Developmental effects of lead acetate on the chick embryo metanephros.

    PubMed

    Errede, M; Elia, G; Bertossi, M; Mulas, M L; Riva, A; Virgintino, D; Benagiano, V; Girolamo, F; Roncali, L; Ambrosi, L

    2001-07-01

    The developmental effects of lead acetate were studied in the chick embryo metanephros, the third renal rudiment that acquires morphological characteristics of functioning kidney already during the prenatal life. Lead exposure was obtained by applying a lead acetate solution on the chick embryo chorioallantoic membrane at the days 9, 10 and 11 of incubation. Quantitative evaluation of the lead concentration assessed by furnace atomic absorption spectrophotometry at the days 14 and 21 of incubation demonstrated metal presence both in the chorioallantoic membrane (CAM) and in metanephros (MN). The lead concentration was higher in CAM than in MN; the metal amount was similar in the CAM of 14 and 21 day embryos, but significantly higher in the 14day embryo MN than in the 21 day embryo MN. Morphological observations on metanephros tissue of control and lead-treated embryos were performed under light, electron transmission and electron scanning microscopes. Peculiar attention was devoted to the expression of the junctional protein connexin 43, the major component of the gap junctions in the renal cells. The results indicated that lead treatment does not intervene in the general differentiation of the metanephric nephrons. The lead is reabsorbed by the proximal tubule cells that are engulfed by endocytotic vacuoles and metal deposits and show long term degenerative changes. Expression of Cx43 protein and ultrastructure of gap junctions between proximal tubule cells appeared to be unchanged. The morphological aspects of the MN corpuscles and tubules agree with the suggestion of a lead cytotoxic effect but do not corroborate, at least in this experimental model, the view of primary damage exerted by lead on the gap junctions of the renal epithelial cells.

  14. Ontogeny of cerebral oxidative metabolism in the chick embryo.

    PubMed

    Gonya-Magee, T; Vannucci, R C

    1982-05-01

    The low cerebral energy requirements of most mammals at birth reflect an immaturity of the central nervous system, and it has been suggested that energy demands in fetuses are even less well developed than in newborns. Furthermore, fetal cerebral energy requirements are presumed to be met predominantly or exclusively by anaerobic glycolysis. To clarify these issues, we investigated cerebral oxidative metabolism in 9-, 14-, 16-, and 19-day-old chick embryos and in newly hatched peeps. Animals were decapitated and quick-frozen in liquid Freon 0--5 min post-mortem. Forebrain extracts were prepared and assayed for ATP, phosphocreatine, glucose, and lactate. Alterations in these metabolites post-decapitation were used to calculate cerebral metabolic rates (delta similar to P) and rates of maximal anaerobic glycolysis (delta lactate). Rates of lactate accumulation during cerebral ischemia increased progressively from embryonic day 9 through hatching. Cerebral metabolic rates were not different in 9-, 14-, and 15-day-old embryos, but increased steadily thereafter. The extent to which total cerebral energy utilization could be derived from anaerobic glycolysis (delta lactate/delta similar to P) increased from a low at day 9 (0.29) to a maximum at day 16 (0.78). The data suggest that, despite the low cerebral metabolic activity of the chick embryo, at no time during development is anaerobic glycolysis capable of entirely supporting the energy needs of the developing brain.

  15. Proliferation and teratogenicity of Aino virus in chick embryos.

    PubMed

    Kitano, Y; Ohzono, H; Shimizu, T

    1996-01-01

    Aino virus (AIV; JaNAr 28 strain) 10(3) TCID50/0.2 ml was inoculated in the yolk sac of 8-day-old chick embryos. Recovery and titration of the virus from various organs including the central nervous system (CNS) and skeletal muscle were performed at 2, 4, 7, 10 and 13 days after inoculation (PI). AIV was systematically disseminated and proliferated even 2 days PI. The titers of the recovered virus from the CNS and from skeletal muscle was the highest at 4 days PI and declined with time, whereas hydranencephaly, arthrogryposis and cerebellar hypoplasia developed at 7 days PI and gradually progressed until 13 days PI.

  16. How the embryo makes a limb: determination, polarity and identity.

    PubMed

    Tickle, Cheryll

    2015-10-01

    The vertebrate limb with its complex anatomy develops from a small bud of undifferentiated mesoderm cells encased in ectoderm. The bud has its own intrinsic polarity and can develop autonomously into a limb without reference to the rest of the embryo. In this review, recent advances are integrated with classical embryology, carried out mainly in chick embryos, to present an overview of how the embryo makes a limb bud. We will focus on how mesoderm cells in precise locations in the embryo become determined to form a limb and express the key transcription factors Tbx4 (leg/hindlimb) or Tbx5 (wing/forelimb). These Tbx transcription factors have equivalent functions in the control of bud formation by initiating a signalling cascade involving Wnts and fibroblast growth factors (FGFs) and by regulating recruitment of mesenchymal cells from the coelomic epithelium into the bud. The mesoderm that will form limb buds and the polarity of the buds is determined with respect to both antero-posterior and dorso-ventral axes of the body. The position in which a bud develops along the antero-posterior axis of the body will also determine its identity - wing/forelimb or leg/hindlimb. Hox gene activity, under the influence of retinoic acid signalling, is directly linked with the initiation of Tbx5 gene expression in the region along the antero-posterior axis of the body that will form wings/forelimbs and determines antero-posterior polarity of the buds. In contrast, Tbx4 expression in the regions that will form legs/hindlimbs is regulated by the homeoprotein Pitx1 and there is no evidence that Hox genes determine antero-posterior polarity of the buds. Bone morphogenetic protein (BMP) signalling determines the region along the dorso-ventral axis of the body in which both wings/forelimbs and legs/hindlimbs develop and dorso-ventral polarity of the buds. The polarity of the buds leads to the establishment of signalling regions - the dorsal and ventral ectoderm, producing Wnts and BMPs

  17. Dual modality optical coherence and whole-body photoacoustic tomography imaging of chick embryos in multiple development stages

    PubMed Central

    Liu, Mengyang; Maurer, Barbara; Hermann, Boris; Zabihian, Behrooz; Sandrian, Michelle G.; Unterhuber, Angelika; Baumann, Bernhard; Zhang, Edward Z.; Beard, Paul C.; Weninger, Wolfgang J.; Drexler, Wolfgang

    2014-01-01

    Chick embryos are an important animal model for biomedical studies. The visualization of chick embryos, however, is limited mostly to postmortem sectional imaging methods. In this work, we present a dual modality optical imaging system that combines swept-source optical coherence tomography and whole-body photoacoustic tomography, and apply it to image chick embryos at three different development stages. The explanted chick embryos were imaged in toto with complementary contrast from both optical scattering and optical absorption. The results serve as a prelude to the use of the dual modality system in longitudinal whole-body monitoring of chick embryos in ovo. PMID:25401028

  18. Ethanol exposure represses osteogenesis in the developing chick embryo.

    PubMed

    Li, Zhong-Yang; Ma, Zheng-Lai; Lu, Wen-Hui; Cheng, Xin; Chen, Jian-Long; Song, Xiao-Yu; Chuai, Manli; Lee, Kenneth Ka Ho; Yang, Xuesong

    2016-07-01

    It is known that excess alcohol consumption during pregnancy can increase the risk of fetal alcohol spectrum disorder (FASD). However, the effect of ethanol exposure on bone morphogenesis in fetus is largely unknown. In this study, we demonstrated that ethanol treatment of gastrulating chick embryos could inhibit long bone (humerus, radius and ulna) development. Histological examination revealed that ethanol exposure reduced the width of the proliferation and hypertrophic zones. In addition, cell proliferation and alkaline phosphatase activities were repressed. We also investigated the effect on chondrogenesis and chondrogenesis was inhibited. Ethanol exposure also induced excess reactive oxygen species (ROS) production and altered the expression of osteogenesis-related genes. The inhibiting effect on flat bone (sclerotic ossicle) and the generation of cranial neural crest cells (progenitors of craniofacial bones) was also presented. In conclusion, ethanol exposure during the embryonic period retards bone development through excess ROS production and altered bone-associated gene expression. PMID:27112526

  19. The generation of vertebral segmental patterning in the chick embryo.

    PubMed

    Senthinathan, Biruntha; Sousa, Cátia; Tannahill, David; Keynes, Roger

    2012-06-01

    We have carried out a series of experimental manipulations in the chick embryo to assess whether the notochord, neural tube and spinal nerves influence segmental patterning of the vertebral column. Using Pax1 expression in the somite-derived sclerotomes as a marker for segmentation of the developing intervertebral disc, our results exclude such an influence. In contrast to certain teleost species, where the notochord has been shown to generate segmentation of the vertebral bodies (chordacentra), these experiments indicate that segmental patterning of the avian vertebral column arises autonomously in the somite mesoderm. We suggest that in amniotes, the subdivision of each sclerotome into non-miscible anterior and posterior halves plays a critical role in establishing vertebral segmentation, and in maintaining left/right alignment of the developing vertebral elements at the body midline.

  20. The chick embryo chorioallantoic membrane (CAM). A multifaceted experimental model.

    PubMed

    Ribatti, Domenico

    2016-08-01

    During avian development the mesodermal layers of the allantois and chorion fuse to form the chorioallantoic membrane (CAM). This structure rapidly expands generating a rich vascular network that provides an interface for gas and waste exchange. The CAM allows to study tissue grafts, tumor growth and metastasis, wound healing, drugs delivery and toxicologic analysis, and angiogenic and anti-angiogenic molecules. The CAM is relatively simple, quick, and low-cost model that allows screening of a large number of pharmacological samples in a short time; does not require administrative procedures for obtaining ethics committee approval for animal experimentation. Moreover, being naturally immunodeficient, the chick embryo may receive transplantations from different tissues and species, without immune responses. PMID:27178379

  1. Creatine regulation in the embryo and growing chick

    PubMed Central

    Ramírez, Oscar; Calva, Edmundo; Trejo, Augusto

    1970-01-01

    1. The absence of creatine was demonstrated enzymically in the hen's-egg yolk and in the albumin contrary to former reports. 2. A comparison of the results obtained by enzymic and colorimetric methods to measure creatine is presented. 3. Creatine phosphate was not detected in the yolk extracts. 4. The content of free arginine enzymically assayed was 15.7μmol in the yolk and 3.38μmol in the albumin. Arginine amounts to practically all of the guanidine compounds in the yolk and one-half of those in the albumin. 5. No glycine amidinotransferase activity was found in the egg-yolk homogenates. 6. The heart of the chick embryo does not receive creatine from the egg and the creatine kinase activity present in this organ starting from the 27th hour of incubation suggests that the enzyme is a constitutive one working probably as an adenosine triphosphatase in a way similar to the kinase isolated from rabbit skeletal muscle. 7. Liver glycine amidinotransferase activity appeared clearly after day 5 of incubation. The specific activity reached a maximum at day 12 and then declined; however, the activity per total mass of liver increased steadily during all the prenatal period. Concomitantly with this steady increase a rise in the creatine content of the whole embryo was observed. An analogous increasing relationship between total liver amidinotransferase activity and liver creatine content was also detected during the postnatal period. 8. Repression of amidinotransferase by creatine cannot be accepted as occurring under physiological conditions since an inverse relationship between the two parameters was not observed. 9. Repression of liver amidinotransferase is observed only when pharmacological concentrations of the exogenous creatine are present in the chick liver. PMID:5493509

  2. Respiratory gas exchange of high altitude adapted chick embryos

    NASA Technical Reports Server (NTRS)

    Wangensteen, O. D.; Rahn, H.; Burton, R. R.; Smith, A. H.

    1974-01-01

    Study of gas exchange by embryos from chickens acclimatized to an altitude of 3800 m. The oxygen partial pressure and carbon dioxide partial pressure differences across the egg shell were measured and found to be less than the values previously reported for sea-level eggs by about a factor of two. Further measurements of embryonic oxygen consumption and shell conductivity to oxygen indicated that, compared to eggs at sea level, oxygen consumption was reduced by a factor of 0.58 while conductivity to oxygen was increased only by a factor of 1.07 in the high-altitude eggs. These independent measurements predict the change in oxygen partial pressure across the egg shell of the high-altitude eggs to be only 0.54 times that of sea-level eggs; the directly measured factor was 0.53. The authors conclude that at high altitude, a major adaptation of the chick embryo is a reduced metabolism which decreases the change in oxygen partial pressure across the egg shell since its gas conductivity remains essentially unchanged.

  3. The chick embryo as an expanding experimental model for cancer and cardiovascular research

    PubMed Central

    Kain, Kristin H.; Miller, James W.I.; Jones-Paris, Celestial R.; Thomason, Rebecca T.; Lewis, John D.; Bader, David M.; Barnett, Joey V.; Zijlstra, Andries

    2014-01-01

    A long and productive history in biomedical research defines the chick as a model for human biology. Fundamental discoveries, including the description of directional circulation propelled by the heart and the link between oncogenes and the formation of cancer, indicate its utility in cardiac biology and cancer. Despite the more recent arrival of several vertebrate and invertebrate animal models during the last century, the chick embryo remains a commonly used model for vertebrate biology and provides a tractable biological template. With new molecular and genetic tools applied to the avian genome the chick embryo is accelerating the discovery of normal development and elusive disease processes. Moreover, progress in imaging and chick culture technologies is advancing real-time visualization of dynamic biological events, such as tissue morphogenesis, angiogenesis and cancer metastasis. A rich background of information, coupled with new technologies and relative ease of maintenance suggest an expanding utility for the chick embryo in cardiac biology and cancer research. PMID:24357262

  4. Morphometric study of cartilage dynamics in the chick embryo tibia. II. Dexamethasone-treated embryos.

    PubMed Central

    Ranz, F B; Aceitero, J; Gaytan, F

    1987-01-01

    The cartilage dynamics in the tibia of dexamethasone-treated chick embryos has been studied by means of morphometric methods. Treated embryos showed a delay in the longitudinal growth of the tibia, as well as in the growth of all structures enclosed by the perichondrium-periosteum. The cartilage formation rate remained nearly unchanged (above 1 mm3/day) from Day 12 to Day 14, whereas the cartilage resorption rate was zero up to Day 13, and showed a non-significant increase from Day 13 onwards. This might be related to the scarcity of resorptive cells found in the cartilage-marrow interface. By Day 14 a certain recovery of the growth rhythm was observed. These results indicate that the greatest effect of dexamethasone occurs at the level of cartilage resorption. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:3446667

  5. Chick embryo proliferation studies using EdU labeling

    PubMed Central

    Warren, Michelle; Puskarczyk, Karolina; Chapman, Susan C.

    2009-01-01

    Cell proliferation studies are an important experimental tool. The most commonly used thymidine analogues, tritiated thymidine and BrdU label cells during S-phase. Both methods have significant drawbacks; low sensitivity in the case of tritiated thymidine and a denaturation step during BrdU detection that destroys most cellular epitopes, requiring careful optimization. The antibody against BrdU is also large and tissue penetration can be difficult. EdU is a closely chemically related to BrdU, with detection achieved by a copper catalyzed reaction requiring a small fluorescently conjugated azide. Cell cultures, flow cytometry and high throughput studies using EdU labeled cells is exceptionally fast and does not require denaturation or antibodies. We have developed a tissue labeling technique in chick embryos using EdU. Following EdU chemistry to detect proliferating cells the tissue can undergo immunolabeling. We demonstrate fluorescent EdU chemistry followed by Tuj1 antibody staining resulting in multiplex fluorescent tissues. PMID:19253396

  6. A detailed description of an economical setup for electroporation of chick embryos in ovo.

    PubMed

    Borges, R M; Horne, J H; Melo, A; Vidal, J T; Vieceli, F M; Melo, M O; Kanno, T Y N; Fraser, S E; Yan, C Y I

    2013-09-01

    One of the challenges of the postgenomic era is characterizing the function and regulation of specific genes. For various reasons, the early chick embryo can easily be adopted as an in vivo assay of gene function and regulation. The embryos are robust, accessible, easily manipulated, and maintained in the laboratory. Genomic resources centered on vertebrate organisms increase daily. As a consequence of optimization of gene transfer protocols by electroporation, the chick embryo will probably become increasingly popular for reverse genetic analysis. The challenge of establishing chick embryonic electroporation might seem insurmountable to those who are unfamiliar with experimental embryological methods. To minimize the cost, time, and effort required to establish a chick electroporation assay method, we describe and illustrate in great detail the procedures involved in building a low-cost electroporation setup and the basic steps of electroporation.

  7. The chick embryo in studies of virulence and immunity with Neisseria Gonorrhoeae.

    PubMed

    Diena, B B; Lavergne, G; Ryan, A; Ashton, F E; Wallace, R; Perry, M; Daoust, V

    1975-12-01

    Intravenous inoculation of 11-day old chick embryos with Neisseria gonorrhoeae has confirmed the original observation of Bumgarner and Finkelstein that T1 and T2 gonocci are significantly more virulent than T3 and T4. Pili do not seem to be solely responsible for this virulence, since elimination of pili did not effect either the viability or the virulence of N. gonorrhoeae. In neutralization studies, there was only one log difference between the ability of normal and hyperimmune rabbit serum to protect the embryo against gonoccocal infection. However, when mouse sera were used in the same chick embryo system a clear difference was noted between the protective activity of normal serum and that antisera elicited in mice by purified gonococcal antigens. It is suggested therefore that mouse antisera be used in this chick embryo model for the assay for gonococcal antigens.

  8. Acutely altered hemodynamics following venous obstruction in the early chick embryo.

    PubMed

    Stekelenburg-de Vos, Sandra; Ursem, Nicolette T C; Hop, Wim C J; Wladimiroff, Juriy W; Gittenberger-de Groot, Adriana C; Poelmann, Robert E

    2003-03-01

    In the venous clip model specific cardiac malformations are induced in the chick embryo by obstructing the right lateral vitelline vein with a microclip. Clipping alters venous return and intracardiac laminar blood flow patterns, with secondary effects on the mechanical load of the embryonic myocardium. We investigated the instantaneous effects of clipping the right lateral vitelline vein on hemodynamics in the stage-17 chick embryo. 32 chick embryos HH 17 were subdivided into venous clipped (N=16) and matched control embryos (N=16). Dorsal aortic blood flow velocity was measured with a 20 MHz pulsed Doppler meter. A time series of eight successive measurements per embryo was made starting just before clipping and ending 5h after clipping. Heart rate, peak systolic velocity, time-averaged velocity, peak blood flow, mean blood flow, peak acceleration and stroke volume were determined. All hemodynamic parameters decreased acutely after venous clipping and only three out of seven parameters (heart rate, time-averaged velocity and mean blood flow) showed a recovery to baseline values during the 5h study period. We conclude that the experimental alteration of venous return has major acute effects on hemodynamics in the chick embryo. These effects may be responsible for the observed cardiac malformations after clipping.

  9. Ethical euthanasia and short-term anesthesia of the chick embryo.

    PubMed

    Aleksandrowicz, Ewa; Herr, Ingrid

    2015-01-01

    Fertilized chicken eggs are suggested as an alternative to mammalian models. The chorioallantoic membrane (CAM) of the chick embryo is widely used for examination of angiogenesis, xenotransplants and for virus production. Unfortunately, it is mostly not taken into account, that the chick embryo's ability to experience pain starts to develop at day 7 of breeding. In our view, this model is only in accordance with the 3 R principles, if an appropriate anesthesia of the chick embryo in potentially painful procedures is provided. Although many experimental approaches are performed on the none-innervated CAM, the euthanasia of the embryo strongly requires a more human technique than the usually used freezing at -20°C, decapitation or in ovo fixation with paraformaldehyde without prior anesthesia. However, protocols regarding feasible and ethical methods for anesthesia and euthanasia of avian embryos are currently not available. Therefore, we established an easy and reliable method for the euthanasia and short-term anesthesia of the chick embryo.

  10. The effect of thalidomide in chicken embryos.

    PubMed

    Stephens, Trent D

    2009-08-01

    Early in the history of the thalidomide disaster, chick embryos were "eliminated" as useful in the study of thalidomide. One reason for that conclusion was that many of the early experiments were flawed. We employed a number of experiments to expose chick embryos to thalidomide. Our data show that thalidomide does cause limb reduction defects in chick embryos as long as the embryos are directly exposed to the drug. The most useful techniques are implanting thalidomide-soaked beads into the embryo immediately adjacent to the limb territory or soaking presumptive chick limb territories in thalidomide and then grafting the explants to a host embryo celom. Thalidomide affects the chick limb grafted to a host embryo in a dose response fashion. Furthermore, S-thalidomide and S-EM12 are more teratogenic than R-thalidomide and R-EM12.

  11. Differential deployment of paralogous Wnt genes in the mouse and chick embryo during development

    PubMed Central

    Martin, Audrey; Maher, Stephanie; Summerhurst, Kristen; Davidson, Duncan; Murphy, Paula

    2012-01-01

    SUMMARY Genes encoding Wnt ligands are crucial in body patterning and are highly conserved among metazoans. Given their conservation at the protein-coding level, it is likely that changes in where and when these genes are active are important in generating evolutionary variations. However, we lack detailed knowledge about how their deployment has diverged. Here, we focus on four Wnt subfamilies (Wnt2, Wnt5, Wnt7, and Wnt8) in mammalian and avian species, consisting of a paralogous gene pair in each, believed to have duplicated in the last common ancestor of vertebrates. We use three-dimensional imaging to capture expression patterns in detail and carry out systematic comparisons. We find evidence of greater divergence between these subgroup paralogues than the respective orthologues, consistent with some level of subfunctionalization/neofunctionalization in the common vertebrate ancestor that has been conserved. However, there were exceptions; in the case of chick Wnt2b, individual sites were shared with both mouse Wnt2 and Wnt2b. We also find greater divergence, between paralogues and orthologues, in some subfamilies (Wnt2 and Wnt8) compared to others (Wnt5 and Wnt7) with the more highly similar expression patterns showing more extensive expression in more structures in the embryo. Wnt8 genes were most restricted and most divergent. Major sites of expression for all subfamilies include CNS, limbs, and facial region, and in general there were more similarities in gene deployment in these territories with divergent patterns featuring more in organs such as heart and gut. A detailed comparison of gene expression patterns in the limb showed similarities in overall combined domains across species with notable differences that may relate to lineage-specific morphogenesis. PMID:23017026

  12. Neuronal damage in chick and rat embryos following X-irradiation

    SciTech Connect

    Schneider, B.F.; Norton, S.

    1980-12-01

    Exposure of rat and chick embryos to X-irradiation at the time of development of neurons at the telencephalic-diencephalic border results in prolonged damage to neurons in this area as measured by neuronal nuclear size. A dose of 100 rads to the seven-day-old chick embryo has about the same effect as 125 rads to the 15-day-old rat fetus. The nuclear volume of large, multipolar neurons in the chick paleostriatum primitivum and the rat lateral preoptic area are reduced from 10 to 15%. Larger doses of X-irradiation to the chick (150 and 200 rads) cause progressively greater reductions in nuclear size. The large neurons which were measured in the rat and chick are morphologically similar in the two species. Both contain cytoplasmic acetylcholinesterase and have several branched, spiny dendritic processes. The similarity of response of chick and rat neurons to X-irradiation diminishes the significance of maternal factors as the cause of the effects of fetal irradiation in these experiments.

  13. Chick embryos can form teratomas from microinjected mouse embryonic stem cells.

    PubMed

    Haraguchi, Seiki; Matsubara, Yuko; Hosoe, Misa

    2016-02-01

    We examined whether chick embryos are a suitable experimental model for the evaluation of pluripotency of stem cells. Mouse embryonic stem cells (mESCs) expressing the reporter gene, LacZ or GFP were injected into the subgerminal cavity of blastoderms (freshly oviposited) or the marginal vein of chick embryos (2 days of incubation). Injected mESCs were efficiently incorporated into the body and extra-embryonic tissues of chick embryos and formed small clusters. Increased donor cell numbers injected were positively associated with the efficiency of chimera production, but with lower viability. A single mESC injected into the blastoderm proliferated into 34.7 ± 3.8 cells in 3 days, implying that the chick embryo provides an optimal environment for the growth of xenogenic cells. In the embryo body, mESCs were interspersed as small clustered chimeras in various tissues. Teratomas were observed in the yolk sac and the brain with three germ layers. In the yolk sac, clusters of mESCs gradually increased in volume and exhibited varied morphology such as a water balloon-like or dark-red solid mass. However, mESCs in the brain developed into a large soft tissue mass of whitish color and showed a tendency to differentiate into ectodermal lineage cells, including primitive neural ectodermal and neuronal cells expressing the neurofilament protein. These results indicate that chick embryos are useful for the teratoma formation assays of mESCs and have a broad-range potential as an experimental host model. PMID:26691605

  14. Effects of brief hypoxia and hyperoxia on tissue element levels in the development chick embryo

    SciTech Connect

    Richards, M.P.; Stock, M.K.; Metcalfe, J. Oregon Health Sciences Univ., Portland )

    1991-03-15

    Brief hypoxia or hyperoxia has been shown to affect growth and metabolism of chick embryos during the later stages of development. The objective of this experiment was to alter the availability of oxygen to chick embryos developing in ovo and to determine the effects on tissue levels of Zn, Cu, Fe and Mn. Hypoxia reduced embryo, heart, brain and liver wts (wet wt), whereas, hyperoxia increased embryo, heart, lung and liver wts compared to normoxic controls. Chorioallantoic membrane (CAM) wt was increased by hypoxia and reduced by hyperoxia. Livers from hyperoxic embryos contained more Zn, Fe and Mn and less Cu than livers from hypoxic or normoxic embryos. Tissue levels of Zn, Cu, Fe and Mn were reduced in brains from hypoxic compared to hyperoxic or normoxic embryos. Hyperoxia increased the concentrations of Zn and Cu in CAM; whereas, hypoxia reduced the levels of Zn and Fe. The amounts of Zn and Cu were increased in hyperoxic compared to normoxic lungs. Hearts from hyperoxic embryos had more Zn, Cu and Mn than hypoxic or normoxic hearts. Hypoxic yolk sac contained more Zn, Cu and Mn than hyperoxic or normoxic yolk sac. Except for yolk sac, the amounts of Zn, Cu, Fe and Mn in tissues from normoxic embryos increased from day 15 to day 18 of incubation in concert with tissue growth. The authors conclude that the availability of O{sub 2} to the developing chick embryo affects tissue trace element levels either through its effects on tissue growth or via effects on the regulation of trace element uptake and assimilation by the tissues.

  15. Development of the endolymphatic sac in chick embryos, with reference to the degradation of otoconia

    NASA Technical Reports Server (NTRS)

    Yoshihara, T.; Kaname, H.; Narita, N.; Ishii, T.; Igarashi, M.; Fermin, C. D.

    1992-01-01

    The endolymphatic sac of chick embryos (from embryonic day 7 to 1-day-old chicks) was studied light- and electron-microscopically. At stage 30-31 (embryonic day 7-7.5), the epithelial cells of the endolymphatic sac were cuboidal to columnar in shape. Microvilli were relatively well developed. The intercellular space was wide. In the endolymphatic space of the endolymphatic sac, varying shapes and sizes of otoconia-like bodies were often observed. Intracytoplasmic phagosomes containing these bodies were rarely found. After stage 37 (embryonic day 11), otoconia-like bodies in the endolymphatic sac decreased in number and size. They were almost the same as the otoconia in the macular organs, ultrastructurally. These findings indicate that the endolymphatic sac of the chick embryos may possess the function of otoconial degradation and removal of calcium from otoconia.

  16. Adrenocortical suppression in highland chick embryos is restored during incubation at sea level.

    PubMed

    Salinas, Carlos E; Villena, Mercedes; Blanco, Carlos E; Giussani, Dino A

    2011-01-01

    By combining the chick embryo model with incubation at high altitude, this study tested the hypothesis that development at high altitude is related to a fetal origin of adrenocortical but not adrenomedullary suppression and that hypoxia is the mechanism underlying the relationship. Fertilized eggs from sea-level or high altitude hens were incubated at sea level or high altitude. Fertilized eggs from sea-level hens were also incubated at altitude with oxygen supplementation. At day 20 of incubation, embryonic blood was taken for measurement of plasma corticotropin, corticosterone, and Po(2). Following biometry, the adrenal glands were collected and frozen for measurement of catecholamine content. Development of chick embryos at high altitude led to pronounced adrenocortical blunting, but an increase in adrenal catecholamine content. These effects were similar whether the fertilized eggs were laid by sea-level or high altitude hens. The effects of high altitude on the stress axes were completely prevented by incubation at high altitude with oxygen supplementation. When chick embryos from high altitude hens were incubated at sea level, plasma hormones and adrenal catecholamine content were partially restored toward levels measured in sea-level chick embryos. There was a significant correlation between adrenocortical blunting and elevated adrenal catecholamine content with both asymmetric growth restriction and fetal hypoxia. The data support the hypothesis tested and provide evidence to isolate the direct contribution of developmental hypoxia to alterations in the stress system.

  17. Melatonin rescues cardiovascular dysfunction during hypoxic development in the chick embryo.

    PubMed

    Itani, Nozomi; Skeffington, Katie L; Beck, Christian; Niu, Youguo; Giussani, Dino A

    2016-01-01

    There is a search for rescue therapy against fetal origins of cardiovascular disease in pregnancy complicated by chronic fetal hypoxia, particularly following clinical diagnosis of fetal growth restriction (FGR). Melatonin protects the placenta in adverse pregnancy; however, whether melatonin protects the fetal heart and vasculature in hypoxic pregnancy independent of effects on the placenta is unknown. Whether melatonin can rescue fetal cardiovascular dysfunction when treatment commences following FGR diagnosis is also unknown. We isolated the effects of melatonin on the developing cardiovascular system of the chick embryo during hypoxic incubation. We tested the hypothesis that melatonin directly protects the fetal cardiovascular system in adverse development and that it can rescue dysfunction following FGR diagnosis. Chick embryos were incubated under normoxia or hypoxia (14% O2) from day 1 ± melatonin treatment (1 mg/kg/day) from day 13 of incubation (term ~21 days). Melatonin in hypoxic chick embryos rescued cardiac systolic dysfunction, impaired cardiac contractility and relaxability, increased cardiac sympathetic dominance, and endothelial dysfunction in peripheral circulations. The mechanisms involved included reduced oxidative stress, enhanced antioxidant capacity and restored vascular endothelial growth factor expression, and NO bioavailability. Melatonin treatment of the chick embryo starting at day 13 of incubation, equivalent to ca. 25 wk of gestation in human pregnancy, rescues early origins of cardiovascular dysfunction during hypoxic development. Melatonin may be a suitable antioxidant candidate for translation to human therapy to protect the fetal cardiovascular system in adverse pregnancy.

  18. [The action of cisplatin on the developing meso- and metanephros of chick embryos].

    PubMed

    Zemanová, Z; Bakhteeva, V T; Gambarian, S P; Tichý, V

    1989-01-01

    Injection of various doses of cisplatin to 2-14-day chick embryos showed that within 2-8 days of incubation cisplatin produces total toxic effect, the number of dead embryos being dependent on a dose of the drug. Within 9-16 days of incubation, i.e. a period when both the mature mesonephros and the developing metanephros are in action, no significant changes were observed in the content of urea and uric acid, the weight of the meso- and metanephros, their water content, and ion content of the blood. Electron microscopic studies revealed no structural changes in the renal tubules. The data obtained suggest that cisplatin does not produce any nephrotoxic effect in chick embryos irrespectively of their age.

  19. The Use of Chick Embryos to Study Wnt Activity Gradients.

    PubMed

    Galli, Lisa M; Barnes, Tiffany; Burrus, Laura W

    2016-01-01

    The chick spinal cord provides a valuable model for assessing Wnt signaling activity. Loss or gain of function constructs that are transfected by electroporation can be directed to a single side of the spinal cord, thus leaving the contralateral side as an internal control. Here, we describe a method for measuring Wnt signaling via the use of BAT-Gal, a β-catenin dependent Wnt reporter. PMID:27590153

  20. Innervation of the undifferentiated limb bud in rabbit embryo.

    PubMed Central

    Cameron, J; McCredie, J

    1982-01-01

    The concept that there are no nerves in the limb bud of mammalian embryos prior to differentiation has been re-examined. Rabbit embryos were collected at 260 and 290 hours gestation, which is prior to cartilage formation in the forelimb at 320 hours. Forelimb buds and adjacent neural tube were excised, fixed and embedded for light and electron microscopy. The limb buds were sectioned in two planes by serial 1 micrometer sections and inspected by light microscopy. Bundles of nerve fibres were seen within the proximal third of the limb bud, with distal ramification into adjacent zones of condensing mesenchyme. Electron microscopy confirmed the presence of axons and associated immature Schwann cells. These results demonstrate the existence of an anatomical framework through which a neurotrophic influence might be brought to bear upon mesenchyme prior to early differentiation. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 PMID:7130041

  1. Growth, development and pairing of Leucochloridiomorpha constantiae (Trematoda) metacercariae on the chorio-allantois of chick embryos cultivated in vitro.

    PubMed

    Fried, B; Fine, R H; Felter, B L

    1980-08-01

    A simple in vitro technique was devised to culture chick embryos in Petri dishes from the 4th to the 21st day of incubation. Leucochloridiomorpha constantiae (Trematoda) metacercariae were placed either singly or multiply (5/embryo) on the chorio-allantois of in vitro grown embryos on day 7 and were removed on day 14. Growth and development studies were also made on worms grown singly or multiply (5/chick) in the bursa of Fabricius of the domestic chick. Worms grown singly or multiply in embryos were sexually mature, although eggs from these worms were abnormal when compared with eggs from worms recovered from chicks. The mean body area of worms from chicks was 2-3 times greater than that of worms from embryos. The mean body area of single worms from embryos was significantly larger than that of worms grown multiply in this site. However, the mean body area of multiple worms from the chick was significantly larger than that of single worms from this site. Worm pairs or clusters were seen in all embryos with the multiple infections. PMID:7422365

  2. Synthetic retinoids, retinobenzoic acids, Am80, Am580 and Ch55 regulate morphogenesis in chick limb bud.

    PubMed

    Tamura, K; Kagechika, H; Hashimoto, Y; Shudo, K; Ohsugi, K; Ide, H

    1990-10-01

    The retinobenzoic acids Am80, Am580 and Ch55 are synthetic stable analogs of retinoic acid (RA), and show very strong differentiation-inducing activity in human myelogeneous leukemia cell line HL-60. To examine the effects of these synthetic retinoids on limb pattern formation, AG1-X2 beads containing these retinoids were applied to the anterior margin of stage 19-20 chick wing buds. By implanting the beads with 1 microgram/ml retinoids, normal wings were formed and extra digits 2 or 32 were rarely formed. As the retinoid concentrations increased from 10 micrograms/ml to 100 micrograms/ml duplicated limbs 3234, 43234, 432234, 4334 were progressively produced. At higher concentrations, 1 mg/ml, the wings often truncated, although duplication occurred in some embryos. These synthetic analogs seem to have the same degree of morphogenetic potential as RA, since the activity index of these retinoids was similar to that of RA. Since these synthetic retinoids hardly bind to CRABP (cellular retinoic acid-binding protein), it may be possible that the retinoids and RA may affect limb-pattern formation without the interaction with CRABP. It is known that limb buds cannot develop distal structures when the posterior region including all ZPA (zone of polarizing activity) is removed. When beads containing the above mentioned retinoids were implanted to the anterior margin of wing buds from which the posterior one third region including all ZPA had been removed, distal growth of the wing buds and the formation of digit elements were observed. Some of the wing buds produced a completely reverse digit pattern 432. From these results, we discussed the roles of RA in limb development and pattern formation.

  3. Cardiac hypertrophy in chick embryos induced by hypothermia

    SciTech Connect

    Boehm, C.; Johnson, T.R.; Caston, J.D.; Przybylski, R.J.

    1987-01-01

    A decrease in incubation temperature from 38 to 32/sup 0/C elicits a decrease in chicken embryo size and weight with concomitant heart enlargement if done after day 10 of incubation. When assayed at day 18 of incubation with the hypothermia started on day 11 or 14, evidence is presented that the heart enlargement is an hypertrophy with no detectable hyperplasia. Supporting data are presented for various physical parameters showing increases in heart wet and dry weight, volume, area, wall thickness, and cell size. There was little difference in DNA content and nuclear (/sup 3/H)thymidine labeling index between hearts of control and hypothermic embryos. Hearts of hypothermic embryos showed a slight increase in water content and considerable increases in RNA, protein, and glycogen content per unit DNA. The average size of polysomes isolated from hypothermic hearts was larger than that of polysomes isolated from controls. Microscopic studies showed no obvious increase in amount of capillary beds, connective tissue, and myocardial cells. Annulate lamellae were found only in myocardial cells of hypothermic embryos in sparse amounts and low frequency but always associated with large deposits of glycogen.

  4. Hypoxia, hormones, and red blood cell function in chick embryos.

    PubMed

    Dragon, Stefanie; Baumann, Rosemarie

    2003-04-01

    The red blood cell function of avian embryos is regulated by cAMP. Adenosine A(2A) and beta-adrenergic receptor activation during hypoxic conditions cause changes in the hemoglobin oxygen affinity and CO(2) transport. Furthermore, experimental evidence suggests a general involvement of cAMP in terminal differentiation of avian erythroblasts.

  5. Plasminogen-independent fibrinolysis by proteases produced by transformed chick embryo fibroblasts.

    PubMed Central

    Chen, L B; Buchanan, J M

    1975-01-01

    The fibrinolytic activity of proteases secreted by chick embryo fibroblasts infected with Rous sarcoma virus was studied by use of a procedure in which a fibrin clot was formed with highly purified fibrinogen and thrombin above the cell layer. This procedure results in the formation of fibrin that is apparently a more suitable substrate for studies on fibrinolysis than is fibrin prepared by other methods. Since neither plasminogen nor serum were included in the assay system in the present studies, the fibrinolytic activity observed cannot be ascribed to the conversion of the plasminogen in serum to plasmin by a plasminogen activator produced by transformed cells. Our procedure, therefore, measures proteolytic activities other than those reported by previous investigators. Maintenance of some of the transformed phenotypes of Rous sarcoma virus transformed chick embryo fibroblasts such as morpholigical change and increased rate of glucose uptake apparently does not depend on the presence of plasminogen in the culture medium. Images PMID:165484

  6. Physical Mechanisms of Pattern Formation in the Early Chick Embryo

    NASA Astrophysics Data System (ADS)

    Balter, Ariel; Glazier, James; Zaitlen, Benji; Chaplain, Mark; Weijer, Cornelis

    2007-03-01

    Gastrulation marks a critical step in early embryogenesis when the first recognizable patterns are laid down. Although the genome maintains ultimate responsibility for this pattern formation, it cannot actually control the organization of individual cells. The robustness of embryogenic pattern formation suggests that a few simple, physical mechanisms are unleashed and that self-organization results. We perform numerical simulations of early chick gastrulation using an agent based method in which individual cells interact via a handful of behaviors including adhesivity, secretion and chemotaxis. Through these simulations we have identified certain behaviors as being important for various stages and morphological events. For instance, experimental results on primitive streak formation are best reproduced by a model in which the Kohler's Sickle secretes a chemo repellant for streak tip cells, and cell polarization appears to be important for initiating polonaise motion during streak elongation.

  7. Human and rat glioma growth, invasion, and vascularization in a novel chick embryo brain tumor model.

    PubMed

    Cretu, Alexandra; Fotos, Joseph S; Little, Brian W; Galileo, Deni S

    2005-01-01

    The mechanisms that control the insidiously invasive nature of malignant gliomas are poorly understood, and their study would be facilitated by an in vivo model that is easy to manipulate and inexpensive. The developing chick embryo brain was assessed as a new xenograft model for the production, growth, and study of human and rat glioma cell lines. Three established glioma lines (U-87 MG, C6, and 9L) were injected into chick embryo brain ventricles on embryonic day (E) 5 and brains were examined after several days to two weeks after injection. All glioma lines survived, produced vascularized intraventricular tumors, and invaded the brain in a manner similar to that in rodents. Rat C6 glioma cells spread along vasculature and also invaded the neural tissue. Human U-87 glioma cells migrated along vasculature and exhibited slight invasion of neural tissue. Rat 9L gliosarcoma cells were highly motile, but migrated only along the vasculature. A derivative of 9L cells that stably expressed the cell surface adhesion molecule NgCAM/L1 was produced and also injected into chick embryo brain ventricles to see if this protein could facilitate tumor cell migration away from the vasculature into areas such as axonal tracts. 9L/NgCAM cells, however, did not migrate away from the vasculature and, thus, this protein alone cannot be responsible for diffuse invasiveness of some gliomas. 9L/NgCAM cell motility was assessed in vitro using sophisticated time-lapse microscopy and quantitative analysis, and was significantly altered compared to parental 9L cells. These studies demonstrate that the chick embryo brain is a successful and novel xenograft model for mammalian gliomas and demonstrate the potential usefulness of this new model for studying glioma tumor cell growth, vascularization, and invasiveness.

  8. A Case Report of Post Rabipur (Purified Chick Embryo Rabies Vaccine) Acute Disseminated Encephalomyelitis.

    PubMed

    Kumar, Rajesh; Singh, A K Bishorjit; Pradhan, R N; Pathak, Vipin Kumar

    2015-01-01

    Acute disseminated encephalomyelitis (ADEM) is an inflammatory demyelinating disease that typically occurs following a viral infection or vaccination. The incidence of ADEM following vaccination has become very low since introduction of non-neural rabies vaccine and only few cases had been reported due to pure chick embryo derived rabies vaccine (PCERV). Here we are reporting a rare case of delayed post vaccinal ADEM. PMID:26591130

  9. Imidacloprid Exposure Suppresses Neural Crest Cells Generation during Early Chick Embryo Development.

    PubMed

    Wang, Chao-Jie; Wang, Guang; Wang, Xiao-Yu; Liu, Meng; Chuai, Manli; Lee, Kenneth Ka Ho; He, Xiao-Song; Lu, Da-Xiang; Yang, Xuesong

    2016-06-15

    Imidacloprid is a neonicotinoid pesticide that is widely used in the control pests found on crops and fleas on pets. However, it is still unclear whether imidacloprid exposure could affect early embryo development-despite some studies having been conducted on the gametes. In this study, we demonstrated that imidacloprid exposure could lead to abnormal craniofacial osteogenesis in the developing chick embryo. Cranial neural crest cells (NCCs) are the progenitor cells of the chick cranial skull. We found that the imidacloprid exposure retards the development of gastrulating chick embryos. HNK-1, PAX7, and Ap-2α immunohistological stainings indicated that cranial NCCs generation was inhibited after imidacloprid exposure. Double immunofluorescent staining (Ap-2α and PHIS3 or PAX7 and c-Caspase3) revealed that imidacloprid exposure inhibited both NCC proliferation and apoptosis. In addition, it inhibited NCCs production by repressing Msx1 and BMP4 expression in the developing neural tube and by altering expression of EMT-related adhesion molecules (Cad6B, E-Cadherin, and N-cadherin) in the developing neural crests. We also determined that imidacloprid exposure suppressed cranial NCCs migration and their ability to differentiate. In sum, we have provided experimental evidence that imidacloprid exposure during embryogenesis disrupts NCCs development, which in turn causes defective cranial bone development.

  10. Systematic assessment of blood circulation time of functionalized upconversion nanoparticles in the chick embryo

    NASA Astrophysics Data System (ADS)

    Nadort, Annemarie; Liang, Liuen; Grebenik, Ekaterina; Guller, Anna; Lu, Yiqing; Qian, Yi; Goldys, Ewa; Zvyagin, Andrei

    2015-12-01

    Nanoparticle-based delivery of drugs and contrast agents holds great promise in cancer research, because of the increased delivery efficiency compared to `free' drugs and dyes. A versatile platform to investigate nanotechnology is the chick embryo chorioallantoic membrane tumour model, due to its availability (easy, cheap) and accessibility (interventions, imaging). In our group, we developed this model using several tumour cell lines (e.g. breast cancer, colon cancer). In addition, we have synthesized in-house silica coated photoluminescent upconversion nanoparticles with several functional groups (COOH, NH2, PEG). In this work we will present the systematic assessment of their in vivo blood circulation times. To this end, we injected chick embryos grown ex ovo with the functionalized UCNPs and obtained a small amount of blood at several time points after injection to create blood smears The UCNP signal from the blood smears was quantified using a modified inverted microscope imaging set-up. The results of this systematic study are valuable to optimize biochemistry protocols and guide nanomedicine advancement in the versatile chick embryo tumour model.

  11. Involvement of vessels and PDGFB in muscle splitting during chick limb development.

    PubMed

    Tozer, Samuel; Bonnin, Marie-Ange; Relaix, Frédéric; Di Savino, Sandrine; García-Villalba, Pilar; Coumailleau, Pascal; Duprez, Delphine

    2007-07-01

    Muscle formation and vascular assembly during embryonic development are usually considered separately. In this paper, we investigate the relationship between the vasculature and muscles during limb bud development. We show that endothelial cells are detected in limb regions before muscle cells and can organize themselves in space in the absence of muscles. In chick limbs, endothelial cells are detected in the future zones of muscle cleavage, delineating the cleavage pattern of muscle masses. We therefore perturbed vascular assembly in chick limbs by overexpressing VEGFA and demonstrated that ectopic blood vessels inhibit muscle formation, while promoting connective tissue. Conversely, local inhibition of vessel formation using a soluble form of VEGFR1 leads to muscle fusion. The endogenous location of endothelial cells in the future muscle cleavage zones and the inverse correlation between blood vessels and muscle suggests that vessels are involved in the muscle splitting process. We also identify the secreted factor PDGFB (expressed in endothelial cells) as a putative molecular candidate mediating the muscle-inhibiting and connective tissue-promoting functions of blood vessels. Finally, we propose that PDGFB promotes the production of extracellular matrix and attracts connective tissue cells to the future splitting site, allowing separation of the muscle masses during the splitting process.

  12. Pericellular coat of chick embryo chondrocytes: structural role of hyaluronate

    PubMed Central

    1984-01-01

    Chondrocytes produce large pericellular coats in vitro that can be visualized by the exclusion of particles, e.g., fixed erythrocytes, and that are removed by treatment with Streptomyces hyaluronidase, which is specific for hyaluronate. In this study, we examined the kinetics of formation of these coats and the relationship of hyaluronate and proteoglycan to coat structure. Chondrocytes were isolated from chick tibia cartilage by collagenase-trypsin digestion and were characterized by their morphology and by their synthesis of both type II collagen and high molecular weight proteoglycans. The degree of spreading of the chondrocytes and the size of the coats were quantitated at various times subsequent to seeding by tracing phase-contrast photomicrographs of the cultures. After seeding, the chondrocytes attached themselves to the tissue culture dish and exhibited coats within 4 h. The coats reached a maximum size after 3-4 d and subsequently decreased over the next 2-3 d. Subcultured chondrocytes produced a large coat only if passaged before 4 d. Both primary and first passage cells, with or without coats, produced type II collagen but not type I collagen as determined by enzyme-linked immunosorbent assay. Treatment with Streptomyces hyaluronidase (1.0 mU/ml, 15 min), which completely removed the coat, released 58% of the chondroitin sulfate but only 9% of the proteins associated with the cell surface. The proteins released by hyaluronidase were not digestible by bacterial collagenase. Monensin and cycloheximide (0.01-10 microM, 48 h) caused a dose-dependent decrease in coat size that was linearly correlated to synthesis of cell surface hyaluronate (r = 0.98) but not chondroitin sulfate (r = 0.2). We conclude that the coat surrounding chondrocytes is dependent on hyaluronate for its structure and that hyaluronate retains a large proportion of the proteoglycan in the coat. PMID:6501414

  13. Proanthocyanidins Prevent High Glucose-Induced Eye Malformation by Restoring Pax6 Expression in Chick Embryo

    PubMed Central

    Tan, Rui-Rong; Zhang, Shi-Jie; Li, Yi-Fang; Tsoi, Bun; Huang, Wen-Shan; Yao, Nan; Hong, Mo; Zhai, Yu-Jia; Mao, Zhong-Fu; Tang, Lu-Ping; Kurihara, Hiroshi; Wang, Qi; He, Rong-Rong

    2015-01-01

    Gestational diabetes mellitus (GDM) is one of the leading causes of offspring malformations, in which eye malformation is an important disease. It has raised demand for therapy to improve fetal outcomes. In this study, we used chick embryo to establish a GDM model to study the protective effects of proanthocyanidins on eye development. Chick embryos were exposed to high glucose (0.2 mmol/egg) on embryo development day (EDD) 1. Proanthocyanidins (1 and 10 nmol/egg) were injected into the air sac on EDD 0. Results showed that both dosages of proanthocyanidins could prevent the eye malformation and rescue the high glucose-induced oxidative stress significantly, which the similar effects were showed in edaravone. However, proanthocyanidins could not decrease the glucose concentration of embryo eye. Moreover, the key genes regulating eye development, Pax6, was down-regulated by high glucose. Proanthocyanidins could restore the suppressed expression of Pax6. These results indicated proanthocyanidins might be a promising natural agent to prevent high glucose-induced eye malformation by restoring Pax6 expression. PMID:26262640

  14. Proanthocyanidins Prevent High Glucose-Induced Eye Malformation by Restoring Pax6 Expression in Chick Embryo.

    PubMed

    Tan, Rui-Rong; Zhang, Shi-Jie; Li, Yi-Fang; Tsoi, Bun; Huang, Wen-Shan; Yao, Nan; Hong, Mo; Zhai, Yu-Jia; Mao, Zhong-Fu; Tang, Lu-Ping; Kurihara, Hiroshi; Wang, Qi; He, Rong-Rong

    2015-08-07

    Gestational diabetes mellitus (GDM) is one of the leading causes of offspring malformations, in which eye malformation is an important disease. It has raised demand for therapy to improve fetal outcomes. In this study, we used chick embryo to establish a GDM model to study the protective effects of proanthocyanidins on eye development. Chick embryos were exposed to high glucose (0.2 mmol/egg) on embryo development day (EDD) 1. Proanthocyanidins (1 and 10 nmol/egg) were injected into the air sac on EDD 0. Results showed that both dosages of proanthocyanidins could prevent the eye malformation and rescue the high glucose-induced oxidative stress significantly, which the similar effects were showed in edaravone. However, proanthocyanidins could not decrease the glucose concentration of embryo eye. Moreover, the key genes regulating eye development, Pax6, was down-regulated by high glucose. Proanthocyanidins could restore the suppressed expression of Pax6. These results indicated proanthocyanidins might be a promising natural agent to prevent high glucose-induced eye malformation by restoring Pax6 expression.

  15. A new gestational diabetes mellitus model: hyperglycemia-induced eye malformation via inhibition of Pax6 in the chick embryo

    PubMed Central

    Zhang, Shi-Jie; Li, Yi-Fang; Tan, Rui-Rong; Tsoi, Bun; Huang, Wen-Shan; Huang, Yi-Hua; Tang, Xiao-Long; Hu, Dan; Yao, Nan; Yang, Xuesong; Kurihara, Hiroshi; Wang, Qi; He, Rong-Rong

    2016-01-01

    ABSTRACT Gestational diabetes mellitus (GDM) is one of the leading causes of fetal malformations. However, few models have been developed to study the underlying mechanisms of GDM-induced fetal eye malformation. In this study, a high concentration of glucose (0.2 mmol per egg) was injected into the air sac of chick embryos on embryo development day (EDD) 1 to develop a hyperglycemia model. Results showed that 47.3% of embryonic eye malformation happened on EDD 5. In this model, the key genes regulating eye development, Pax6, Six3 and Otx2, were downregulated by hyperglycemia. Among these genes, the expression of Pax6 was the most vulnerable to hyperglycemia, being suppressed by 70%. A reduction in Pax6 gene expression induced eye malformation in chick embryos. However, increased expression of Pax6 in chick embryos could rescue hyperglycemia-induced eye malformation. Hyperglycemia stimulated O-linked N-acetylglucosaminylation, which caused oxidative stress in chick embryos. Pax6 was found to be vulnerable to free radicals, but the antioxidant edaravone could restore Pax6 expression and reverse eye malformation. These results illustrated a successful establishment of a new chick embryo model to study the molecular mechanism of hyperglycemia-induced eye malformation. The suppression of the Pax6 gene is probably mediated by oxidative stress and could be a crucial target for the therapy of GDM-induced embryonic eye malformation. PMID:26744353

  16. Chick embryos have the same pattern of hypoxic lower-brain activation as fetal mammals.

    PubMed

    Landry, Jeremy P; Hawkins, Connor; Lee, Aaron; Coté, Alexandra; Balaban, Evan; Pompeiano, Maria

    2016-01-01

    cFos expression (indicating a particular kind of neuronal activation) was examined in embryonic day (E) 18 chick embryos after exposure to 4 h of either normoxia (21% O2), modest hypoxia (15% O2), or medium hypoxia (10% O2). Eight regions of the brainstem and hypothalamus were surveyed, including seven previously shown to respond to hypoxia in late-gestation mammalian fetuses (Breen et al., 1997; Nitsos and Walker, 1999b). Hypoxia-related changes in chick embryo brain activation mirrored those found in fetal mammals with the exception of the medullary Raphe, which showed decreased hypoxic activation, compared with no change in mammals. This difference may be explained by the greater anapyrexic responses of chick embryos relative to mammalian fetuses. Activation in the A1/C1 region was examined in more detail to ascertain whether an O2-sensitive subpopulation of these cells containing heme oxygenase 2 (HMOX2) may drive hypoxic brain responses before the maturation of peripheral O2-sensing. HMOX2-positive and -negative catecholaminergic cells and interdigitating noncatecholaminergic HMOX2-positive cells all showed significant changes in cFos expression to hypoxia, with larger population responses seen in the catecholaminergic cells. Hypoxia-induced activation of lower-brain regions studied here was significantly better correlated with activation of the nucleus of the solitary tract (NTS) than with that of HMOX2-containing A1/C1 neurons. Together, these observations suggest that (1) the functional circuitry controlling prenatal brain responses to hypoxia is strongly conserved between birds and mammals, and (2) NTS neurons are a more dominant driving force for prenatal hypoxic cFos brain responses than O2-sensing A1/C1 neurons.

  17. Morphogenesis and calcification of the statoconia in the chick (Gallus domesticus) embryo - Implications for future studies

    NASA Technical Reports Server (NTRS)

    Fermin, C. D.; Igarashi, M.

    1985-01-01

    The morphogenesis of the statoconia in the chick, Gallus domesticus, injected with a carbon anhydrase inhibitor is studied. The preparation of the embryo specimens for analysis is described. The early, middle, and late stages of embryonic development are examined. The data reveal that acetozolamide inhibits statoconia formation in the middle stage of development and the calcification process follows statoconia formation. The spatial relationship between the development of type 1 and type 2 hair cells and the appearance and maturation of the statoconia is investigated.

  18. Effectiveness of noise in blocking electromagnetic effects on enzyme activity in the chick embryo.

    PubMed

    Martin, A H; Moses, G C

    1995-05-01

    We have previously demonstrated that exposure of the chick embryo to a 60 Hz, 4 microT split sine wave for the first 72 hours of development causes a significant reduction in the activity of the ectoenzyme 5'-nucleotidase. This reduced activity persisted, throughout the embryonic period, despite further incubation in a field free environment. We also showed that the reduction in 5'NT activity can be localized in the developing brain to the Cerebellum. The present study reveals that superimposition of an electromagnetic noise, of similar amplitude and frequency, can mitigate the effect of the field on 5'NT activity.

  19. In vivo in situ en face optical coherence tomography imaging of chick embryos

    NASA Astrophysics Data System (ADS)

    Leitner, Michael; Castanheira, Joana; Ferreira, Luís; Ferreira, Mónica; Palmeirim, Isabel; Rosa, Carla C.; Podoleanu, Adrian G.

    2009-07-01

    Chick embryos are among the most studied species in development biology because they are easily obtained, highly accessible and present a similar development to that of humans. Normally morphological studies are carried out with confocal microscopy, however in-situ imaging is impossible and in- vivo imaging can only be performed with great difficulty. For confocal microscopy the embryo has to be studied outside the egg, what generally also means a short life expectancy of the embryo. Additionally, extracting the embryo of the egg precludes the possibility of studying its development in its natural environment. In this paper it is shown that en-face optical coherence tomography (en-face OCT) is a possible solution to overcome these difficulties allowing for an in-situ and in-vivo study over a timescale of several days. With en-face OCT it is possible to accompany the development of one single embryo over several days and to acquire high resolution and axially resolved images.

  20. Development of chick embryos in 1 Hz to 100 kHz magnetic fields.

    PubMed

    Juutilainen, J; Saali, K

    1986-01-01

    Chick embryos were exposed during their 48 first hours of development to sinusoidally oscillating magnetic fields. The frequencies 1 Hz, 10 Hz, 16.7 Hz, 30 Hz, 50 Hz, 1 kHz, 10 kHz and 100 kHz, and the field strengths 0.1, 1, 10 and 100 A/m were used. Each exposure group consisted of 20 eggs. After the exposure, the embryos were examined for abnormalities and classified by the developmental stage. The percentage of abnormal embryos (%AE) was significantly increased at frequencies from 16.7 Hz to 100 kHz. Above a threshold field strength of about 0.1 to 1 A/m, %AE was rather independent of the field strength, varying from 16% to 56% in different exposure groups. 13% of the sham-exposed control embryos (n = 150) were abnormal. Only the 0.1 A/m exposure group differed significantly from the controls at 1 Hz, and no significant effect was found at 10 Hz. The developmental stage was in general not affected by the magnetic fields, but some abnormal embryos showed retarded development.

  1. Patterning in time and space: HoxB cluster gene expression in the developing chick embryo.

    PubMed

    Gouveia, Analuce; Marcelino, Hugo M; Gonçalves, Lisa; Palmeirim, Isabel; Andrade, Raquel P

    2015-01-01

    The developing embryo is a paradigmatic model to study molecular mechanisms of time control in Biology. Hox genes are key players in the specification of tissue identity during embryo development and their expression is under strict temporal regulation. However, the molecular mechanisms underlying timely Hox activation in the early embryo remain unknown. This is hindered by the lack of a rigorous temporal framework of sequential Hox expression within a single cluster. Herein, a thorough characterization of HoxB cluster gene expression was performed over time and space in the early chick embryo. Clear temporal collinearity of HoxB cluster gene expression activation was observed. Spatial collinearity of HoxB expression was evidenced in different stages of development and in multiple tissues. Using embryo explant cultures we showed that HoxB2 is cyclically expressed in the rostral presomitic mesoderm with the same periodicity as somite formation, suggesting a link between timely tissue specification and somite formation. We foresee that the molecular framework herein provided will facilitate experimental approaches aimed at identifying the regulatory mechanisms underlying Hox expression in Time and Space.

  2. [Toxic and teratogenic effects of the ammonium salt of fosamine on the development of quail and chick embryos].

    PubMed

    Lutz-Ostertag, Y

    1983-01-01

    The effects of a commercial spray preparation of ammonium salt ppf fosamine (a defoliant) on quail and chick eggs have been studied. The results lead us to conclude that under the stated conditions the product has little embryotoxicity. However, it does have teratogenic effects on the steal and on the cervical, dorsal and posterior axial skeleton. The observed malformations are more severe and appear more frequently in quail than in chick embryos. PMID:6685456

  3. [Toxic and teratogenic effects of the ammonium salt of fosamine on the development of quail and chick embryos].

    PubMed

    Lutz-Ostertag, Y

    1983-01-01

    The effects of a commercial spray preparation of ammonium salt ppf fosamine (a defoliant) on quail and chick eggs have been studied. The results lead us to conclude that under the stated conditions the product has little embryotoxicity. However, it does have teratogenic effects on the steal and on the cervical, dorsal and posterior axial skeleton. The observed malformations are more severe and appear more frequently in quail than in chick embryos.

  4. Inactivated eastern equine encephalomyelitis vaccine propagated in rolling-bottle cultures of chick embryo cells.

    PubMed

    Cole, F E

    1971-11-01

    A method was developed for the production of Eastern equine encephalomyelitis vaccine from virus grown in rolling-bottle cultures (840 cm(2) growth area) of chick embryo cells. The PE-6 strain of virus was propagated in chick embryo cell roller cultures maintained on serum-free medium 199 containing 0.25% human serum albumin and antibiotics (MM). A multiplicity of inoculum of 0.005 yielded acceptable titers of virus at a convenient harvest time of 18 to 24 hr and reduced the carry-over of extraneous material from the virus seed. Growth studies in which 100, 200, or 300 ml of MM was used showed that use of 300 ml of MM offered two advantages: (i) cytopathic effects were less at the 18- to 24-hr harvest time, thereby decreasing cellular material in the final product, and (ii) total virus yield was not substantially reduced, thus permitting large-scale production of virus for further processing. Studies on formalin inactivation at 37 C indicated that the virus was inactivated by 0.05% formalin within 12 to 16 hr and with 0.1% formalin within 6 to 8 hr. Antigen extinction tests in hamsters revealed excellent potency (e.g., median-effective-dose values of 0.069 to 0.012 ml) for both fluid and freeze-dried products. The advantages of the roller-bottle technique in vaccine production are discussed.

  5. The Chick Embryo as an Experimental System for Melanoma Cell Invasion

    PubMed Central

    Busch, Christian; Krochmann, Jelena; Drews, Ulrich

    2013-01-01

    Background A primary cutaneous melanoma will not kill the patient, but its metastases. Since in vitro studies on melanoma cells in 2-D cultures do often not reflect reality, 3-D models might come closer to the physiological situation in the patient during cancer initiation and progression. Methodology/Principal Findings Here, we describe the chick embryo model for in vivo studies of melanoma cell migration and invasion. After transplantation of neural crest-derived melanoma cells into the neural tube, the melanoma cells resume neural crest cell migration along the medial and lateral pathways and finally undergo apoptosis in the target areas. Upon transplantation into ectopic areas such as the hindbrain or the optic cup malignant invasion and local tissue destruction occurs. In contrast, melanocytes are not able to spontaneously resume neural crest cell migration. However, malignant invasion can be induced in melanocytes by pre-treatment with the TGF-beta family members bone morphegenetic protein-2 or nodal. Transplantation of MCF7 breast cancer cells yields a different growth pattern in the rhombencephalon than melanoma cells. Conclusions/Significance The chick embryo model is a feasible, cost-effective in vivo system to study invasion by cancer cells in an embryonic environment. It may be useful to study invasive behavior induced by embryonic oncogenes and for targeted manipulation of melanoma or breast cancer cells aiming at ablation of invasive properties. PMID:23342051

  6. Improved photodynamic activity of porphyrin loaded into nanoparticles: an in vivo evaluation using chick embryos.

    PubMed

    Vargas, Angelica; Pegaz, Bernadette; Debefve, Elodie; Konan-Kouakou, Yvette; Lange, Norbert; Ballini, Jean-Pierre; van den Bergh, Hubert; Gurny, Robert; Delie, Florence

    2004-11-22

    Hydrophobic porphyrins are potentially interesting molecules for the photodynamic therapy (PDT) of solid cancers or ocular vascularization diseases. Their pharmaceutical development is, however, hampered by their lipophilicity, which renders formulation difficult especially when intravenous administration is needed. Encapsulation of a lipophilic derivative of porphyrin, the meso-tetra(p-hydroxyphenyl)porphyrin (p-THPP), into polymeric biodegradable poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles proved to enhance its photodynamic activity against mammary tumour cells when compared to free drug. In order to further investigate these carriers, the efficacy of the encapsulated drug was assessed on the chick embryo chorioallantoic membrane (CAM) model. First, we identified a suitable solvent for the drug in terms of p-THPP solubility and tolerability by chick embryos. This solution was used as a reference. Then, the fluorescence pharmacokinetics and the photodynamic effects of the porphyrin on CAM vessels were evaluated after intravenous administration of either a p-THPP solution (free drug) or the drug loaded into nanoparticles. The results showed that: (i) the drug remained longer in the vascular compartment when incorporated into nanoparticles and (ii) vascular effects of p-THPP after light irradiation were enhanced with nanoparticle carriers. These results are discussed taking into account the extravasation of intravascular circulating photosensitizers and its influence on PDT performance. PMID:15501010

  7. Hypertonic stress regulates amino acid transport and cell cycle proteins in chick embryo hepatocytes.

    PubMed

    Bruscalupi, Giovannella; Massimi, Mara; Spagnuolo, Silvana; Fiore, Anna Maria; Leoni, Silvia

    2012-02-01

    Hyperosmotic stress affects cell growth, decreasing cell volume and increasing the uptake of organic osmolytes. However, the sensitivity of embryonic cells to osmotic treatment remains to be established. We have analysed some aspects of cell-cycle control and amino-acid transport in hypertonic conditions during prenatal life. The effects of hyperosmotic stress on amino-acid uptake mediated by system A, (3)H-thymidine incorporation, and regulation of cell-cycle proteins were analysed in chick embryo hepatocytes. Hypertonic stress increased system A activity and caused cell-cycle delay. Effects on amino-acid transport involved p38 kinase activation and new carrier synthesis. Cyclin D1, cdk4 (cyclin-dependent kinase 4) and PCNA (proliferating-cell nuclear antigen) levels decreased, whereas cyclin E, p21 and p53 levels were unchanged. Incorporation of (3)H-leucine indicated decreased synthesis of cyclin D1. In contrast, analysis of mRNA by qRT-PCR (quantitative real-time PCR) showed a net increase of cyclin D1 transcripts, suggesting post-transcriptional regulation. The data show that chick embryo hepatocytes respond to hyperosmotic conditions by arresting cell growth to prevent DNA damage and increasing osmolyte uptake to regulate cell volume, indicating that the adaptive response to environmental stress exists during prenatal life.

  8. Chick limbs with mouse teeth: an effective in vivo culture system for tooth germ development and analysis.

    PubMed

    Koyama, Eiki; Wu, Changshan; Shimo, Tsuyoshi; Pacifici, Maurizio

    2003-01-01

    Mouse tooth germ development is currently studied by three main approaches: in wild-type and mutant mouse lines, after transplantation of tooth germs to ectopic sites, and in organ culture. The in vivo approaches are the most physiological but do not provide accessibility to tooth germs for further experimental manipulation. Organ cultures, although readily accessible, do not sustain full tooth germ development and are appropriate for short-term analysis. Thus, we sought to establish a new approach that would combine experimental accessibility with sustained development. We implanted fragments of embryonic day 12 mouse embryo first branchial arch containing early bud stage tooth germs into the lateral mesenchyme of day 4-5 chick embryo wing buds in ovo. Eggs were reincubated, and implanted tissues were examined by histochemistry and in situ hybridization over time. The tooth germs underwent seemingly normal growth, differentiation, and morphogenesis. They reached the cap, bell, and crown stages in approximately 3, 6, and 10 days, respectively, mimicking in a striking manner native temporal patterns. To examine mechanisms regulating tooth germ development, we first implanted tooth germ fragments, microinjected them with neutralizing antibodies to the key signaling molecule Sonic hedgehog (Shh), and examined them over time. Tooth germ development was markedly delayed, as revealed by poor morphogenesis and lack of mature ameloblasts and odontoblasts displaying characteristic traits such as an elongated cell shape, nuclear relocalization, and amelogenin gene expression. These phenotypic changes began to be reversed upon further incubation. The data show that the limb bud represents an effective, experimentally accessible as well as economical system for growth and analysis of developing tooth germs. The inhibitory effects of Shh neutralizing antibody treatment are discussed in relation to roles of this signaling pathway proposed by this and other groups previously.

  9. Developmental changes of Insulin-like growth factors in the liver and muscle of chick embryos.

    PubMed

    Liu, Yanli; Guo, Wei; Pu, Zhenyu; Li, Xueyuan; Lei, Xinyu; Yao, Junhu; Yang, Xiaojun

    2016-06-01

    The insulin-like growth factors ( IGFS: ) are synthesized in tissues and play an important role in embryonic development of avian via autocrine/paracrine mechanisms. In the study, mRNA expression of IGFs were detected by real-time PCR in the muscle and liver from d 10 to 20 of chick embryo ( E10: to E20: ). Methylation of IGF1 promoter in the muscle was analyzed by bisulfite sequencing PCR as well as IGF2 promoter in the liver. These results showed that there was obviously IGF1 expression in liver at E19 and E20. The higher IGF1 expression in muscle was found during E15 to E18 with the peak on E17, and then declined. Correspondingly, the lowest methylation level of IGF1 promoter was detectable on the same embryonic d 17. Expression of IGF2 in muscle increased gradually during embryonic growth and showed higher level in the later stages (E17 to E20) when IGF1 expression began to decrease. IGF2 expression in liver reached the first peak on E14, then declined but gradually elevated from E17. IGF2 promoter methylation in liver showed gradual decline on d 12, 15, 17 and 19 of incubation, meanwhile IGF2 expression of liver increased gradually. These results suggested that IGF1 and IGF2 might separately be more important for muscle and liver growth in chick embryonic development. Variation of IGFs expression during the incubation might be concerned with the methylation of gene promoter. The profile of IGFs expression in chick embryonic tissues may be meaningful for understanding organ growth and embryonic development in chick. PMID:26944971

  10. Developmental changes of Insulin-like growth factors in the liver and muscle of chick embryos.

    PubMed

    Liu, Yanli; Guo, Wei; Pu, Zhenyu; Li, Xueyuan; Lei, Xinyu; Yao, Junhu; Yang, Xiaojun

    2016-06-01

    The insulin-like growth factors ( IGFS: ) are synthesized in tissues and play an important role in embryonic development of avian via autocrine/paracrine mechanisms. In the study, mRNA expression of IGFs were detected by real-time PCR in the muscle and liver from d 10 to 20 of chick embryo ( E10: to E20: ). Methylation of IGF1 promoter in the muscle was analyzed by bisulfite sequencing PCR as well as IGF2 promoter in the liver. These results showed that there was obviously IGF1 expression in liver at E19 and E20. The higher IGF1 expression in muscle was found during E15 to E18 with the peak on E17, and then declined. Correspondingly, the lowest methylation level of IGF1 promoter was detectable on the same embryonic d 17. Expression of IGF2 in muscle increased gradually during embryonic growth and showed higher level in the later stages (E17 to E20) when IGF1 expression began to decrease. IGF2 expression in liver reached the first peak on E14, then declined but gradually elevated from E17. IGF2 promoter methylation in liver showed gradual decline on d 12, 15, 17 and 19 of incubation, meanwhile IGF2 expression of liver increased gradually. These results suggested that IGF1 and IGF2 might separately be more important for muscle and liver growth in chick embryonic development. Variation of IGFs expression during the incubation might be concerned with the methylation of gene promoter. The profile of IGFs expression in chick embryonic tissues may be meaningful for understanding organ growth and embryonic development in chick.

  11. FT-IR microscopic mappings of early mineralization in chick limb bud mesenchymal cell cultures

    NASA Technical Reports Server (NTRS)

    Boskey, A. L.; Camacho, N. P.; Mendelsohn, R.; Doty, S. B.; Binderman, I.

    1992-01-01

    Chick limb bud mesenchymal cells differentiate into chondrocytes and form a cartilaginous matrix in culture. In this study, the mineral formed in different areas within cultures supplemented with 4 mM inorganic phosphate, or 2.5, 5.0, and 10 mM beta-glycerophosphate (beta GP), was characterized by Fourier-transform infrared (FT-IR) microscopy. The relative mineral-to-matrix ratios, and distribution of crystal sizes at specific locations throughout the matrix were measured from day 14 to day 30. The only mineral phase detected was a poorly crystalline apatite. Cultures receiving 4 mM inorganic phosphate had smaller crystals which were less randomly distributed around the cartilage nodules than those in the beta GP-treated cultures. beta GP-induced mineral consisted of larger, more perfect apatite crystals. In cultures receiving 5 or 10 mM beta GP, the relative mineral-to-matrix ratios (calculated from the integrated intensities of the phosphate and amide I bands, respectively) were higher than in the cultures with 4 mM inorganic phosphate or in the in vivo calcified chick cartilage.

  12. Analysis of cerebro-spinal fluid protein composition in early developmental stages in chick embryos.

    PubMed

    Gato, A; Martín, P; Alonso, M I; Martín, C; Pulgar, M A; Moro, J A

    2004-04-01

    Foetal cerebro-spinal fluid (CSF) has a very high protein concentration when compared to adult CSF, and in many species five major protein fractions have been described. However, the protein concentration and composition in CSF during early developmental stages remains largely unknown. Our results show that in the earliest stages (18 to 30 H.H.) of chick development there is a progressive increase in CSF protein concentration until foetal values are attained. In addition, by performing electrophoretic separation and high-sensitivity silver staining, we were able to identify a total of 21 different protein fractions in the chick embryo CSF. In accordance with the developmental pattern of their concentration, these can be classified as follows: A: high-concentration fractions which corresponded with the ones described in foetal CSF by other authors; B: low-concentration fractions which remained stable throughout the period studied; C: low-concentration fractions which show changes during this period. The evolution and molecular weight of the latter group suggest the possibility of an important biological role. Our data demonstrate that all the CSF protein fractions are present in embryonic serum; this could mean that the specific transport mechanisms in neuroepithelial cells described in the foetal period evolve in very early stages of development. In conclusion, this paper offers an accurate study of the protein composition of chick embryonic CSF, which will help the understanding of the influences on neuroepithelial stem cells during development and, as a result, the appropriate conditions for the in vitro study of embryonic/foetal nervous tissue cells. PMID:15039986

  13. Embryonic cerebrospinal fluid regulates neuroepithelial survival, proliferation, and neurogenesis in chick embryos.

    PubMed

    Gato, Angel; Moro, J A; Alonso, M I; Bueno, D; De La Mano, A; Martín, C

    2005-05-01

    Early in development, the behavior of neuroepithelial cells is controlled by several factors, which act in a developmentally regulated manner. Diffusible factors are secreted locally by the neuroepithelium itself, although other nearby structures may also be involved. Evidence suggests a physiological role for the cerebrospinal fluid in the development of the brain. Here, using organotypic cultures of chick embryo neuroepithelial explants from the mesencephalon, we show that the neuroepithelium in vitro is not able to self-induce cell survival, replication, and neurogenesis. We also show that the embryonic cerebrospinal fluid (E-CSF) promotes neuroepithelial stem cell survival and induces proliferation and neurogenesis in mesencephalic explants. These data strongly suggest that E-CSF is involved in the regulation of neuroepithelial cells behavior, supporting the hypothesis that this fluid plays a key role during the early development of the central nervous system. PMID:15803475

  14. NMR Based Cerebrum Metabonomic Analysis Reveals Simultaneous Interconnected Changes during Chick Embryo Incubation.

    PubMed

    Feng, Yue; Zhu, Hang; Zhang, Xu; Wang, Xuxia; Xu, Fuqiang; Tang, Huiru; Ye, Chaohui; Liu, Maili

    2015-01-01

    To find out if content changes of the major functional cerebrum metabolites are interconnected and formed a network during the brain development, we obtained high-resolution magic-angle-spinning (HR-MAS) 1H NMR spectra of cerebrum tissues of chick embryo aged from incubation day 10 to 20, and postnatal day 1, and analyzed the data with principal component analysis (PCA). Within the examined time window, 26 biological important molecules were identified and 12 of them changed their relative concentration significantly in a time-dependent manner. These metabolites are generally belonged to three categories, neurotransmitters, nutrition sources, and neuronal or glial markers. The relative concentration changes of the metabolites were interconnected among/between the categories, and, more interestingly, associated with the number and size of Nissl-positive neurons. These results provided valuable biochemical and neurochemical information to understand the development of the embryonic brain.

  15. The Chick Embryo Chorioallantoic Membrane as an In Vivo Assay to Study Antiangiogenesis

    PubMed Central

    Ribatti, Domenico

    2010-01-01

    Antiangiogenesis, e.g., inhibition of blood vessel growth, is being investigated as a way to prevent the growth of tumors and other angiogenesis-dependent diseases. Pharmacological inhibition interferes with the angiogenic cascade or the immature neovasculature with synthetic or semi-synthetic substances, endogenous inhibitors or biological antagonists. The chick embryo chorioallantoic membrane (CAM) is an extraembryonic membrane, which serves as a gas exchange surface and its function is supported by a dense capillary network. Because its extensive vascularization and easy accessibility, CAM has been used to study morphofunctional aspects of the angiogenesis process in vivo and to study the efficacy and mechanism of action of pro- and anti-angiogenic molecules. The fields of application of CAM in the study of antiangiogenesis, including our personal experience, are illustrated in this review article.

  16. NMR Based Cerebrum Metabonomic Analysis Reveals Simultaneous Interconnected Changes during Chick Embryo Incubation

    PubMed Central

    Feng, Yue; Zhu, Hang; Zhang, Xu; Wang, Xuxia; Xu, Fuqiang; Tang, Huiru; Ye, Chaohui; Liu, Maili

    2015-01-01

    To find out if content changes of the major functional cerebrum metabolites are interconnected and formed a network during the brain development, we obtained high-resolution magic-angle-spinning (HR-MAS) 1H NMR spectra of cerebrum tissues of chick embryo aged from incubation day 10 to 20, and postnatal day 1, and analyzed the data with principal component analysis (PCA). Within the examined time window, 26 biological important molecules were identified and 12 of them changed their relative concentration significantly in a time-dependent manner. These metabolites are generally belonged to three categories, neurotransmitters, nutrition sources, and neuronal or glial markers. The relative concentration changes of the metabolites were interconnected among/between the categories, and, more interestingly, associated with the number and size of Nissl-positive neurons. These results provided valuable biochemical and neurochemical information to understand the development of the embryonic brain. PMID:26485040

  17. High glucose environment inhibits cranial neural crest survival by activating excessive autophagy in the chick embryo

    PubMed Central

    Wang, Xiao-Yu; Li, Shuai; Wang, Guang; Ma, Zheng-Lai; Chuai, Manli; Cao, Liu; Yang, Xuesong

    2015-01-01

    High glucose levels induced by maternal diabetes could lead to defects in neural crest development during embryogenesis, but the cellular mechanism is still not understood. In this study, we observed a defect in chick cranial skeleton, especially parietal bone development in the presence of high glucose levels, which is derived from cranial neural crest cells (CNCC). In early chick embryo, we found that inducing high glucose levels could inhibit the development of CNCC, however, cell proliferation was not significantly involved. Nevertheless, apoptotic CNCC increased in the presence of high levels of glucose. In addition, the expression of apoptosis and autophagy relevant genes were elevated by high glucose treatment. Next, the application of beads soaked in either an autophagy stimulator (Tunicamycin) or inhibitor (Hydroxychloroquine) functionally proved that autophagy was involved in regulating the production of CNCC in the presence of high glucose levels. Our observations suggest that the ERK pathway, rather than the mTOR pathway, most likely participates in mediating the autophagy induced by high glucose. Taken together, our observations indicated that exposure to high levels of glucose could inhibit the survival of CNCC by affecting cell apoptosis, which might result from the dysregulation of the autophagic process. PMID:26671447

  18. Exposure to Excess Phenobarbital Negatively Influences the Osteogenesis of Chick Embryos

    PubMed Central

    Yan, Yu; Cheng, Xin; Yang, Ren-Hao; Li, He; Chen, Jian-Long; Ma, Zheng-Lai; Wang, Guang; Chuai, Manli; Yang, Xuesong

    2016-01-01

    Phenobarbital is an antiepileptic drug that is widely used to treat epilepsy in a clinical setting. However, a long term of phenobarbital administration in pregnant women may produce side effects on embryonic skeletogenesis. In this study, we aim to investigate the mechanism by which phenobarbital treatment induces developmental defects in long bones. We first determined that phenobarbital treatment decreased chondrogenesis and inhibited the proliferation of chondrocytes in chick embryos. Phenobarbital treatment also suppressed mineralization in both in vivo and in vitro long bone models. Next, we established that phenobarbital treatment delayed blood vessel invasion in a cartilage template, and this finding was supported by the down-regulation of vascular endothelial growth factor in the hypertrophic zone following phenobarbital treatment. Phenobarbital treatment inhibited tube formation and the migration of human umbilical vein endothelial cells. In addition, it impaired angiogenesis in chick yolk sac membrane model and chorioallantoic membrane model. In summary, phenobarbital exposure led to shortened lengths of long bones during embryogenesis, which might result from inhibiting mesenchyme differentiation, chondrocyte proliferation, and delaying mineralization by impairing vascular invasion. PMID:27746734

  19. Characterization of concentration gradients of a morphogenetically active retinoid in the chick limb bud

    PubMed Central

    1987-01-01

    It has long been suggested that the generation of biological patterns depends in part on gradients of diffusible substances. In an attempt to bridge the gap between this largely theoretical concept and experimental embryology, we have examined the physiology of diffusion gradients in an actual embryonic field. In particular, we have generated in the chick wing bud concentration gradients of the morphogenetically active retinoid TTNPB, (E)-4-[2-(5,6,7,8-tetrahydro- 5,5,8,8-tetramethyl-2-naphthalenyl)-1-prope nyl] benzoic acid, a synthetic vitamin A compound. Upon local application of TTNPB the normal 234 digit pattern is duplicated in a way that correlates with the geometry of the underlying TTNPB gradient; low doses of TTNPB lead to a shallow gradient and an additional digit 2, whereas higher doses result in a steep, far-reaching gradient and patterns with additional digits 3 and 4. The experimentally measured TTNPB distribution along the anteroposterior axis, can be modeled by a local source and a dispersed sink. This model correctly predicts the site of specification of digit 2, and provides an empirical estimate of the diffusion coefficient (D) of retinoids in embryonic limb tissue. The numerical value of approximately 10(-7) cm2s-1 for D suggests that retinoids are not freely diffusible in the limb rudiment, but interact with the previously identified cellular retinoic acid binding protein. In addition, D affords an estimate of the time required to establish a diffusion gradient as 3 to 4 h. This time span is in a range compatible with the time scale of pattern specification in developing vertebrate limbs. Our studies support the view that diffusion of morphogenetic substances is a plausible mechanism of pattern formation in secondary embryonic fields. PMID:3667700

  20. A chick embryo with a yet unclassified type of cephalothoracopagus malformation and a hypothesis for explaining its genesis.

    PubMed

    Maurer, B; Geyer, S H; Weninger, W J

    2013-06-01

    Cephalothoracopagus embryos are conjoined twins, who share parts of their heads, necks and bodies. Our study aims at presenting a detailed morphological analysis of a cephalothoracopagus chick embryo of developmental stage 31. Because none of the existing theories can explain the genesis of the phenotype of this embryo, we also suggest a hypothesis, which explains it. Beside the cephalothoracopagus embryo, we investigated five control embryos. With the aid of the high-resolution episcopic microscopy (HREM) technique, we created digital volume data and three-dimensional (3D) computer models of the organs and arteries of the embryos. We used the 3D models for topological analysis and for measuring the diameters of the great intrathoracic arteries. The malformed embryo showed two body backs, each containing a notochord, spinal cord and dorsal aorta. The body backs continued into separated lower bodies. The embryo had a single, four-chambered heart, single respiratory tract and single upper alimentary tract. The topology of the pharyngeal arch arteries was normal, and the diameters of these arteries were similar to that of the control embryos. We classified the embryo we investigated as a yet unknown malformation and suggest a hypothesis explaining its genesis. PMID:22971166

  1. A chick embryo with a yet unclassified type of cephalothoracopagus malformation and a hypothesis for explaining its genesis.

    PubMed

    Maurer, B; Geyer, S H; Weninger, W J

    2013-06-01

    Cephalothoracopagus embryos are conjoined twins, who share parts of their heads, necks and bodies. Our study aims at presenting a detailed morphological analysis of a cephalothoracopagus chick embryo of developmental stage 31. Because none of the existing theories can explain the genesis of the phenotype of this embryo, we also suggest a hypothesis, which explains it. Beside the cephalothoracopagus embryo, we investigated five control embryos. With the aid of the high-resolution episcopic microscopy (HREM) technique, we created digital volume data and three-dimensional (3D) computer models of the organs and arteries of the embryos. We used the 3D models for topological analysis and for measuring the diameters of the great intrathoracic arteries. The malformed embryo showed two body backs, each containing a notochord, spinal cord and dorsal aorta. The body backs continued into separated lower bodies. The embryo had a single, four-chambered heart, single respiratory tract and single upper alimentary tract. The topology of the pharyngeal arch arteries was normal, and the diameters of these arteries were similar to that of the control embryos. We classified the embryo we investigated as a yet unknown malformation and suggest a hypothesis explaining its genesis.

  2. Mechanical Effects of the Surface Ectoderm on Optic Vesicle Morphogenesis in the Chick Embryo

    PubMed Central

    Hosseini, Hadi S.; Beebe, David C.; Taber, Larry A.

    2014-01-01

    Precise shaping of the eye is crucial for proper vision. Here, we use experiments on chick embryos along with computational models to examine the mechanical factors involved in the formation of the optic vesicles (OVs), which grow outward from the forebrain of the early embryo. First, mechanical dissections were used to remove the surface ectoderm (SE), a membrane that contacts the outer surfaces of the OVs. Principal components analysis of OV shapes suggests that the SE exerts asymmetric loads that cause the OVs to flatten and shear caudally during the earliest stages of eye development and later to bend in the caudal and dorsal directions. These deformations cause the initially spherical OVs to become pear-shaped. Exposure to the myosin II inhibitor blebbistatin reduced these effects, suggesting that cytoskeletal contraction controls OV shape by regulating tension in the SE. To test the physical plausibility of these interpretations, we developed 2-D finite-element models for frontal and transverse cross-sections of the forebrain, including frictionless contact between the SE and OVs. With geometric data used to specify differential growth in the OVs, these models were used to simulate each experiment (control, SE removed, no contraction). For each case, the predicted shape of the OV agrees reasonably well with experiments. The results of this study indicate that differential growth in the OV and external pressure exerted by the SE are suffcient to cause the global changes in OV shape observed during the earliest stages of eye development. PMID:25458577

  3. Histological characterisation of the ethanol-induced microphthalmia phenotype in a chick embryo model system.

    PubMed

    Kennelly, Kevin; Brennan, Deirdre; Chummun, Kushal; Giles, Seamus

    2011-09-01

    The eye is a sensitive indicator of the teratogenic effects of ethanol with ophthalmic defects such as microphthalmia frequently observed in FAS children. In this study, we have optimised the chick-embryo model system to investigate ethanol-induced ocular defects. Injection of 20% ethanol (125μl) directly into the yolk sac of HH-stage 7 embryos resulted in an overall 30% incidence of eye anomalies including microphthalmia. Ocular measurements showed that this treatment regime caused a significant reduction in overall globe size. Histological examination of microphthalmic specimens revealed three subgroups: (1) all ocular structures developed but were significantly retarded compared to age matched controls, (2) the bi-layered optic cup developed but with no evidence of lens induction, and (3) the optic vesicle failed to invaginate but remained as a vesicular structure comprising of a single layer of retinal pigment cells with no evidence of a neuro-retinal cell layer or lens structure. Further analysis identified clusters of apoptotic bodies in the ventral telencephalon, a region responsible for the expression of important genes in ocular specification. These results support a growing body of evidence, indicating that ethanol targets inductive signals in early eye development involving lens formation and retinal ganglion cell differentiation. The possible involvement of Shh, Fgf8, Bmp4 and Pax6 is discussed in relation to these outcomes.

  4. Identification of a developmentally modulated, intermediate filament associated protein in the chick embryo.

    PubMed

    Vincent, M; Lahaie, C

    1988-03-01

    We report here the detection of a high molecular weight (greater than 400,000) cytoskeletal protein in the myogenic and neural tube derived structures of the chick embryo using a monoclonal antibody, F51H2. Immunohistological analysis reveals that this protein is concentrated in the myotome part of the somites, in the heart primordium, and in the neural tube at the end of the 2nd day of incubation. In cultured fibroblasts, the antibody appeared to decorate a filamentous network, although immunoreactivity was not detected on mesenchymal cells in situ. This network was also observed in cultured myoblasts where it has been demonstrated to be coincident to that of desmin. In colchicine-treated cells the immunoreactivity coincided with the perinuclear cap formed by the collapse of intermediate filaments (IFs). Immunoblot experiments confirmed the early distribution of F51H2 antigen in muscle and nerve tissues and its concentration in a salt-resistant IF-rich fraction of muscle tissues. In addition, there is a progressive loss of immunoreactivity during development. The immunoreactive band on sodium dodecyl sulfate gels was faint in tissues from newly hatched chickens and absent in adult tissues. It is suggested that the monoclonal antibody observed herein reacts with an embryo specific high molecular weight protein that is associated with IFs.

  5. Morphometric study of cartilage dynamics in the chick embryo tibia. I. Methodology and tissue compartments in normal embryos.

    PubMed Central

    Gaytan, F; Ranz, F B; Aceitero, J

    1987-01-01

    Cartilage dynamics during the development of the chick embryo tibia has been studied by means of morphometric methods, from the 11th to the 14th days. The volume densities of the structures enclosed by the perichondrium-periosteum did not change significantly through the age span studied, whereas the absolute volumes of these structures increased during the whole period under investigation. The cartilage volume showed the most rapid increase from Day 12 to Day 13 (by a factor of x1.74). The volume of the invading connective and vascular tissue increased rapidly from Day 11 to Day 14. The rate of cartilage formation decreased from 7.60 +/- 1.02 to 3.82 +/- 0.89 mm3/day (from Day 13 to Day 14), whereas the rate of cartilage resorption increased until Day 13 (by a factor of x2.71), reaching a plateau after this age. Although cartilage formation was higher than resorption during this period, the changes found by Day 13 indicate that shortly after this age cartilage resorption will predominate over cartilage formation, leading to the disappearance of the cartilaginous model. Images Fig. 3 PMID:3446666

  6. Adhesion between cells, diffusion of growth factors, and elasticity of the AER produce the paddle shape of the chick limb

    PubMed Central

    Popławski, Nikodem J.; Swat, Maciej; Gens, J. Scott; Glazier, James A.

    2007-01-01

    A central question in developmental biology is how cells interact to organize into tissues? In this paper, we study the role of mesenchyme-ectoderm interaction in the growing chick limb bud using Glazier and Graner's cellular Potts model, a grid-based stochastic framework designed to simulate cell interactions and movement. We simulate cellular mechanisms including cell adhesion, growth, and division and diffusion of morphogens, to show that differential adhesion between the cells, diffusion of growth factors through the extracellular matrix, and the elastic properties of the apical ectodermal ridge together can produce the proper shape of the limb bud. PMID:18167520

  7. PTEN is involved in modulation of vasculogenesis in early chick embryos.

    PubMed

    Li, Yan; Wang, Xiao-Yu; Wu, Ting; Chuai, Manli; Lee, Kenneth Ka Ho; Wang, Li-Jing; Yang, Xuesong

    2013-06-15

    PTEN is a tumor suppressor gene that is mutated and/or deleted in many types of tumor. This gene also plays a very distinct role in the early stages of embryonic development such as cell migration, proliferation and migration. Nevertheless, little is known of the function of PTEN in vasculogenesis during chick embryonic development. In this study, we used in situ hybridization to first demonstrate the expression pattern of PTEN during gastrulation. PTEN was found mainly expressed in the blood islands of area opaca, the neural tube and mesodermal structures. Overexpression of PTEN obstructed the epithelial-mesenchymal transition (EMT) process in the primitive streak. EMT is the first prerequisite required for the emigration of hemangioblasts during vasculogenesis. When PTEN expression was silenced, we observed that it produced an adverse effect on mesodermal cell emigration to the extra-embryonic blood islands. In addition, we also demonstrated that even if the perturbed-PTEN cells did not affect the formation of blood islands, migrant mesodermal cells overexpressing wt PTEN-GFP had difficulties integrating into the blood islands. Instead, these cells were either localized on the periphery of the blood islands or induced to differentiate into endothelial cells if they managed to integrate into blood islands. Development of the intra-embryonic primary vascular plexus was also affected by overexpression of PTEN. We proposed that it was elevated PTEN lipid phosphatase activity that was responsible for the morphogenetic defects induced by PTEN overexpression. In this context, we did not find PTEN affecting VEGF signaling. In sum, our study has provided evidence that PTEN is involved in vasculogenesis during the early stages of chick embryo development.

  8. Microgravity in the STS-29 space shuttle discovery affected the vestibular system of chick embryos

    NASA Technical Reports Server (NTRS)

    Fermin, C. D.; Martin, D.; Jones, T.; Vellinger, J.; Deuser, M.; Hester, P.; Hullinger, R.

    1996-01-01

    Out of 32 embryos flown (16 @ E2 + 16 @ E9) for 5 days, 16 survived. All sixteen E2 were dead at landing. Eight were opened and eight were incubated at 1.0G. Autopsy showed that 4 E2 survived over 24 hours in space. Eight E14 hatched without anatomical malformations, and 8 E14 were fixed. The height of the macular epithelia was 31 mu m (mean) in control and 26 mu m in flight chicks. The cross-sectional area of macular nuclei of control was 17 mu m(2) for hair cells and 14 mu m(2) in supporting cells. In flight, cross-sectional area was 17 mu m(2) in hair cells and 15 mu m(2) in supporting cells (n=250). The shape factor of cartilage cells (1.0 = perfect circle) between control (mean = 0.70) and flight (mean = 0.72), and the area of cartilaginous cells between controls (mean = 9 mu m(2)) and flight (mean = 9 mu m(2)) did not differ (n=300). The nuclei of support cells were closer to the basement membrane in flight than in control chicks. The immunoreactivity of otoconia with anti keratan, fibronectin or chrondroitin sulfate was not different between flight and control ears. There were more afferent fibers inside the macular epithelia of flight (p<0.05) than control. Three of 8 flight animals had elevated vestibular thresholds (VT), with normal mean response amplitudes and latencies. Modified afferent innervation patterns requiring weeks to compensate are sufficient to elevate VT, and should be investigated further. Other reversible (sublethal) microgravity effects on sensory epithelia (vacuoles, swelling, etc) require quantification.

  9. THE SUSCEPTIBILITY OF CHICK EMBRYO SKIN ORGAN CULTURES TO INFLUENZA VIRUS FOLLOWING EXCESS VITAMIN A

    PubMed Central

    Huang, J. S.; Bang, F. B.

    1964-01-01

    The conversion of chick embryonic epidermis to mucous epithelium by excess vitamin A in organ culture as reported by Fell and Mellanby (5) was shown to be accompanied by a corresponding change of susceptibility to influenza and vaccinia viruses. Untreated epidermis of 10- to 12-day chick embryos supported the growth of influenza (PR8) virus in organ cultures and a maximum infectivity (EID50) titer was reached 2 to 3 days after infection. At the same time) the epidermis showed squamous keratinization, beginning about the 4th day of cultivation. Addition of excess vitamin A (40 µg per ml) to the skin organ culture induced the following changes: (a) mucous metaplasia of the epidermis which was usually first evident after 4 to 5 days in the vitamin A medium, (b) increase in the daily and maximum yield of influenza virus, if the epidermis had been grown for 4 or more days in the vitamin A medium before infection took place, and (c) decrease in the production of vaccinia virus under similar conditions. The maximum yield of both viruses remained unchanged, however, if excess vitamin A was introduced to the organ culture at the time of virus inoculation. The magnitude of increase in the yield of influenza virus in this organ culture system was found to be proportionally related to the concentration of vitamin A added 4 or more days before inoculation of this virus. Increasing doses of vitamin A however, had no effect on the short-term growth of influenza virus in tissue cultures of chorio-allantoic membrane. Observation on the early period (2 to 12 hours) of influenza virus growth initiated in the 4-day organ cultures of chick embryonic skin showed no significant difference in virus production between the normal and the vitamin A medium groups. The change of virus specificity apparently is not due to the presence of excess vitamin A per se, but appears to be related to the change of differentiation produced in the organ culture system. PMID:14206436

  10. Measuring the electric activity of chick embryos heart through 16 bit audio card monitored by the Goldwavetm software

    NASA Astrophysics Data System (ADS)

    Silva, Dilson; Cortez, Celia Martins

    2015-12-01

    In the present work we used a high-resolution, low-cost apparatus capable of detecting waves fit inside the sound bandwidth, and the software package GoldwaveTM for graphical display, processing and monitoring the signals, to study aspects of the electric heart activity of early avian embryos, specifically at the 18th Hamburger & Hamilton stage of the embryo development. The species used was the domestic chick (Gallus gallus), and we carried out 23 experiments in which cardiographic spectra of QRS complex waves representing the propagation of depolarization waves through ventricles was recorded using microprobes and reference electrodes directly on the embryos. The results show that technique using 16 bit audio card monitored by the GoldwaveTM software was efficient to study signal aspects of heart electric activity of early avian embryos.

  11. The lathyrogenic effect of isonicotinic acid hydrazide (INAH) on the chick embryo and its reversal by pyridoxal.

    PubMed

    LEVENE, C I

    1961-04-01

    When applied to the chorio-allantoic membrane of the chick embryo, isoniazid was shown to produce an increase in the fragility of the embryo and in the amount of collagen which was extractable from the bones with cold 1 M sodium chloride. The administration of pyridoxal reversed these phenomena almost completely. The effect of isoniazid differed from that of beta-aminopropionitrile in that the latter was of greater magnitude, and was not affected by pyridoxal; whereas beta-aminopropionitrile caused skeletal deformities, isoniazid even at 12 times the concentration produced no deformities. The aldehyde group of pyridoxal was shown to be necessary for its interaction with isoniazid.

  12. Survival and neurite growth of chick embryo spinal cord cells in serum-free culture.

    PubMed

    Tanaka, H; Obata, K

    1982-07-01

    Cell survival and neurite growth were investigated in serum-free spinal cord cell cultures on polyornithine coating (PORN). Cells were obtained from 6- or 7-day-old chick embryos. Isolated spinal cord cells required promoting factors for their survival and neurite growth. The survival-promoting factors were initially present in spinal cord cells. High density cultures, co-cultures with spinal cord explants, and spinal cord extract promoted survival of isolated spinal cord cells in MEM with no additives. Other tissue extracts (brain, liver, heart and skeletal muscle), serum, and serum-free conditioned medium (SF-CM) of muscle or glioma C6 cells also promoted survival. The active substances in the brain extract and SF-CM were shown to be protein and were separated into 3 fractions (approximately molecular weight 150,000, 70,000, 40,000) by gel filtration chromatography. Survival and neurite growth were suggested to be promoted by different factors because: (1) survival was promoted by both tissue extract and SF-CM, but neurite growth was promoted only by SF-CM; (2) the neurite growth-stimulating activity of SF-CM was lost following dialysis and heat (100 degrees C, 2 min) treatment; however, the survival-promoting activity was not. It was also suggested that spinal cord cells produce neurite growth promoting factors, but did not initially contain these factors.

  13. Magnesium and calcium effects on uptake of hexoses and uridine by chick embryo fibroblasts.

    PubMed Central

    Bowen-Pope, D F; Rubin, H

    1977-01-01

    Cultures of chick embryo fibroblasts were incubated for varying periods in media containing different concentrations of Ca2+ and Mg2+-Mg2+ deprivation produced a gradual decrease in the Vmax of the glucose transport system for the D-glucose analogues 3-O-[3H]methyl-D-glucose and 2-deoxy-D-[3H]glucose and a parallel decrease in the rate of production of lactate from glucose in the medium. It greatly reduced the rates of [3H]uridine uptake and incorporation by decreasing the Vmax of the uridine transport system. Addition of Mg2+ to Mg2+-deprived cultures rapidly increased the rate of [3H]uridine uptake without requiring protein synthesis and increased the rate of 2-deoxy-D-[3H]glucose uptake without requiring RNA synthesis. These effects of changes in Mg2+ concentration qualitatively reproduce the effects of such variables as cell density and serum and insulin concentrations. Ca2+ deprivation resulted in similar, though much smaller, changes in the activities of the two transport systems, but also greatly increased the "leakiness" of the cells to the nontransported hexose L-[3H]glucose. PMID:266198

  14. Chick embryo metanephros: the glycosylation pattern as revealed with lectin conjugates.

    PubMed

    Gheri, G; Bryk, S G; Sgambati, E; Russo, G

    1993-05-01

    Fragments of metanephros were taken from chick embryos and studied from the 7th to the 21st d of incubation. A battery of 7 different horseradish peroxidase-labelled lectins (PNA, ConA, DBA, SBA, LTA, WGA and UEA I) was used to analyse the distribution and changes of carbohydrate moieties in glycoconjugates along the metanephric nephron from the S-shaped body stage onwards. DBA and SBA reacted for a short time at some sites during the considered period of incubation. Provided WGA and ConA reacted with most of the nephric components, the almost ubiquitous presence of N-acetyl-D-glucosamine and alpha-D-mannose was demonstrated. SBA and LTA were found to be good markers of the proximal tubule. On the 12th d of incubation, sialic acid was found in the podocytes, capillary walls, and the connecting and collecting ducts. On the same day, other oligosaccharides were present at the nephric tubular components. The simultaneous presence of sialic acid and other sugar residues may be significant for the identification of the exact stage of incubation at which metanephric activity starts. The possible role of some sugar residues for the regulation of metanephric activity is discussed.

  15. Vitamin D metabolism and its possible role in the developing chick embryo.

    PubMed Central

    Kubota, M; Abe, E; Shinki, T; Suda, T

    1981-01-01

    The relationship between bone formation and vitamin D metabolism was investigated in the developing chick embryo. Fertilized White Leghorn eggs were incubated at 38 degrees C in an incubator for 21 days. The fresh weight and calcium content of embryonic tibiae began to increase at day 12 and attained maximal values at day 19. Bone alkaline phosphatase and citrate decarboxylation activities, both of which represent osteoblastic activity, also began to increase at days 10-12, reached maximal values at day 19 and sharply declined thereafter. Both bone enzyme activities were highly correlated with CA2+-binding activity in the chorioallantoic membrane measured by the Chelex 100 assay. When mesonephric and metanephric homogenates were incubated with 25-hydroxy[3H]cholecalciferol, a marked and concomitant increase occurred in the metanephric 1 alpha- and 24-hydroxylase activity after day 14. The production of 1 alpha, 25-dihydroxycholecalciferol attained a maximal value at day 19 and decreased thereafter, whereas that of 24,25-dihydroxycholecalciferol continued to increase until hatching. The production rate of 1 alpha, 25-dihydroxycholecalciferol by the metanephros coincided with the changes in Ca2+-binding activity in the chorioallantoic membrane and osteoblastic activity. Since both intestinal calcium absorption and bone mineral mobilization do not occur in embryonic life, these results support the idea that 1 alpha, 25-dihydroxycholecalciferol may be involved directly in bone formation or induction of a calcium-binding protein in the chorioallantoic membrane. PMID:7305973

  16. The Bioaccumulation and Toxicity of Platinum Group Metals in Developing Chick Embryos

    NASA Astrophysics Data System (ADS)

    Pavel, Ioana; Monahan, Jennifer; Markopoulos, Marjorie; Gagnon, Zofia; Nejame, Britney; Cawley, Jacob; Reens, David

    2008-10-01

    Recent studies showed that platinum group metals (PGMs) such as Pt, Pd, and Rh from automobile catalytic converters, can accumulate in the soft tissues of a variety of living organisms. However, the effects of PGMs on bone and organs development of animals are not clearly understood. To examine these aspects, developing chick embryos were injected with 0.1, 1.0, 5, or 10 ppm solutions of Pt, Rh, Pd, or with a PGMs mixture. 1) Pathological Changes: were observed for all PGM treatments above 1 ppm. Bone Cells Assesment: Chondrocyte cells in thibiotarsus showed decreased diameter and length. 2) PGMs Accumulation in Tissues: was quantified by GFAAS spectrometry on finely ground tissue powder. 3) Bone Demineralization: was detected by micro-Raman spectroscopy imaging on paraffin embedded bone sections. 4) DNA Damage in Cells: was determined by using a Comet assay and fluorescence spectroscopy. Oxidative Damage in Tissues: was analyzed using a glutathione peroxidase assay. The overall results indicated that PGMs presence in our environment raises concerns about their long-term health effects on all organisms.

  17. Survival and neurite growth of chick embryo spinal cord cells in serum-free culture.

    PubMed

    Tanaka, H; Obata, K

    1982-07-01

    Cell survival and neurite growth were investigated in serum-free spinal cord cell cultures on polyornithine coating (PORN). Cells were obtained from 6- or 7-day-old chick embryos. Isolated spinal cord cells required promoting factors for their survival and neurite growth. The survival-promoting factors were initially present in spinal cord cells. High density cultures, co-cultures with spinal cord explants, and spinal cord extract promoted survival of isolated spinal cord cells in MEM with no additives. Other tissue extracts (brain, liver, heart and skeletal muscle), serum, and serum-free conditioned medium (SF-CM) of muscle or glioma C6 cells also promoted survival. The active substances in the brain extract and SF-CM were shown to be protein and were separated into 3 fractions (approximately molecular weight 150,000, 70,000, 40,000) by gel filtration chromatography. Survival and neurite growth were suggested to be promoted by different factors because: (1) survival was promoted by both tissue extract and SF-CM, but neurite growth was promoted only by SF-CM; (2) the neurite growth-stimulating activity of SF-CM was lost following dialysis and heat (100 degrees C, 2 min) treatment; however, the survival-promoting activity was not. It was also suggested that spinal cord cells produce neurite growth promoting factors, but did not initially contain these factors. PMID:7104764

  18. Immunohistochemical localization of oestrogen receptor alpha in the various cell categories of chick embryo ovary.

    PubMed

    Civinini, A; Chimenti, C; Gallo, V P

    2010-12-01

    The immunohistochemical (IHC) localization of oestrogen receptor alpha (ERα) was studied in the developing left ovary of 14.5-day-old chick embryos. The study was focused in particular on distinguishing in cortex and medulla the different cell categories that proved positive to the reaction, in order to gain further understanding of gonadal cell interactions during ovarian development. Immunostained cells were observed in both the cortex and medulla, but the reactivity for ERα was discontinuous, probably due to variable cell requirements. In the cortex, positivity was observed in cells of the ovarian surface epithelium, in germ cells and in prefollicular cells. In the medulla, positivity was found in the following cell categories: interstitial cells, poorly differentiated somatic cord cells, including those delimiting lacunae, germ cells and their accompanying cells of epithelial origin. Furthermore, the IHC results showed that the intracellular localization of the antigen was cytoplasmic, nuclear, or both. The significance of ERα presence and intracellular localization was discussed in relation and as supplementary to previous research by various Authors. In particular, as regards the unusual cytoplasmic immunoreactivity, a gradual shift of ERα localization from cytoplasmic to nuclear during the embryonic period is suggested.

  19. Angiogenic response induced by acellular brain scaffolds grafted onto the chick embryo chorioallantoic membrane.

    PubMed

    Ribatti, Domenico; Conconi, Maria Teresa; Nico, Beatrice; Baiguera, Silvia; Corsi, Patrizia; Parnigotto, Pier Paolo; Nussdorfer, Gastone G

    2003-10-31

    The repair and regeneration of injured tissues and organs depend on the re-establishment of the blood flow needed for cellular infiltration and metabolic support. Among the various materials used in tissue reconstruction, acellular scaffolds have recently been utilized. In this study, we investigated the angiogenic response induced by acellular brain scaffolds implanted in vivo onto the chick embryo chorioallantoic membrane (CAM), a useful model for such investigations. The results show that acellular brain scaffolds are able to induce a strong angiogenic response, comparable to that of fibroblast growth factor-2 (FGF-2), a well known angiogenic cytokine. The response may be considered dependent on a direct angiogenic effect exerted by the scaffold, because no inflammatory infiltrate was detectable in CAM's mesenchyme beneath the implant. Acellular brain scaffolds might induce the release of endogenous angiogenic factors, such as FGF-2 and vascular endothelial growth factor (VEGF) released from the extracellular matrix of the developing CAM. In addition, the angiogenic response may depend, in part, also on the presence in the acellular matrix of transforming growth factor beta 1 (TGFbeta1).

  20. RNA interference is ineffective as a routine method for gene silencing in chick embryos as monitored by fgf8 silencing

    PubMed Central

    2005-01-01

    The in vivo accessibility of the chick embryo makes it a favoured model system for experimental developmental biology. Although the range of available techniques now extends to miss-expression of genes through in ovo electroporation, it remains difficult to knock out individual gene expression. Recently, the possibility of silencing gene expression by RNAi in chick embryos has been reported. However, published studies show only discrete quantitative differences in the expression of the endogenous targeted genes and unclear morphological alterations. To elucidate whether the tools currently available are adequate to silence gene expression sufficiently to produce a clear and specific null-like mutant phenotype, we have performed several experiments with different molecules that trigger RNAi: dsRNA, siRNA, and shRNA produced from a plasmid coexpressing green fluorescent protein as an internal marker. Focussing on fgf8 expression in the developing isthmus, we show that no morphological defects are observed, and that fgf8 expression is neither silenced in embryos microinjected with dsRNA nor in embryos microinjected and electroporated with a pool of siRNAs. Moreover, fgf8 expression was not significantly silenced in most isthmic cells transformed with a plasmid producing engineered shRNAs to fgf8. We also show that siRNA molecules do not spread significantly from cell to cell as reported for invertebrates, suggesting the existence of molecular differences between different model systems that may explain the different responses to RNAi. Although our results are basically in agreement with previously reported studies, we suggest, in contrast to them, that with currently available tools and techniques the number of cells in which fgf8 gene expression is decreased, if any, is not sufficient to generate a detectable mutant phenotype, thus making RNAi useless as a routine method for functional gene analysis in chick embryos. PMID:15951844

  1. Apical accumulation of MARCKS in neural plate cells during neurulation in the chick embryo

    PubMed Central

    Zolessi, Flavio R; Arruti, Cristina

    2001-01-01

    Background The neural tube is formed by morphogenetic movements largely dependent on cytoskeletal dynamics. Actin and many of its associated proteins have been proposed as important mediators of neurulation. For instance, mice deficient in MARCKS, an actin cross-linking membrane-associated protein that is regulated by PKC and other kinases, present severe developmental defects, including failure of cranial neural tube closure. Results To determine the distribution of MARCKS, and its possible relationships with actin during neurulation, chick embryos were transversely sectioned and double labeled with an anti-MARCKS polyclonal antibody and phalloidin. In the neural plate, MARCKS was found ubiquitously distributed at the periphery of the cells, being conspicuously accumulated in the apical cell region, in close proximity to the apical actin meshwork. This asymmetric distribution was particularly noticeable during the bending process. After the closure of the neural tube, the apically accumulated MARCKS disappeared, and this cell region became analogous to the other peripheral cell zones in its MARCKS content. Actin did not display analogous variations, remaining highly concentrated at the cell subapical territory. The transient apical accumulation of MARCKS was found throughout the neural tube axis. The analysis of another epithelial bending movement, during the formation of the lens vesicle, revealed an identical phenomenon. Conclusions MARCKS is transiently accumulated at the apical region of neural plate and lens placode cells during processes of bending. This asymmetric subcellular distribution of MARCKS starts before the onset of neural plate bending. These results suggest possible upstream regulatory actions of MARCKS on some functions of the actin subapical meshwork. PMID:11329360

  2. Sustained phosphorylation of MARCKS in differentiating neurogenic regions during chick embryo development.

    PubMed

    Zolessi, F R; Arruti, C

    2001-10-24

    MARCKS, a substrate for several kinases, has critical functions in morphogenetic processes involved in the development of the nervous system. We previously described the purification of MARCKS from chick embryo brain, using a monoclonal antibody (mAb 3C3), raised against embryonic neural retina. Here we show that mAb 3C3 is an antibody sensitive to phosphorylation state. We used it to explore the appearance and developmental progression of phospho-MARCKS (ph-MARCKS) during initial stages of neurogenesis in retina and spinal cord, and compared its distribution with total MARCKS. Before the onset of neural differentiation, MARCKS protein was already accumulated in neural and non-neural embryonic tissues, while ph-MARCKS immunoreactivity was weak, although ubiquitous too. A sudden increase of ph-MARCKS, paralleling a total MARCKS augmentation, was particularly noticeable in the earliest differentiating neurons in the neural retina. Ganglion cells displayed a high ph-MARCKS signal in the soma, as well as in the growing axon. A short time thereafter, a similar increase of ph-MARCKS was present across the entire width of the neural retina, where the differentiation of other neurons and photoreceptors occurs. The increase of ph-MARCKS in cells took place before the detection of the transcription factor Islet-1/2, an early neuronal differentiation molecular marker, in cells of the same region. Analogous phenomena were observed in cervical regions of the spinal cord, where motor neurons were differentiating. Neurogenic regions in the spinal cord contained higher amounts of ph-MARCKS than the floor plate. Taken together, these results strongly suggest that the appearance and relatively long-lasting presence of ph-MARCKS polypeptides are related to specific signaling pathways active during neurogenesis.

  3. Changes in glycoconjugate expression during early chick embryo development: a lectin-binding study.

    PubMed

    Griffith, C M; Sanders, E J

    1991-10-01

    A selection of lectins was used to investigate developmentally regulated changes in the distribution of cell surface oligosaccharides during the gastrulation and neurulation stages of early chick embryo development. Lectins from three specificity classes were used: glucose/mannose specificity (concanavalin A [Con A], Lens culinaris agglutinin [LCA], Pisum sativum agglutinin [PSA]); N-acetylglucosamine specificity (Lycopersicon esculentum agglutinin [LEA], wheat germ agglutinin [WGA], succinylated WGA [sWGA]); N-acetylgalactosamine/galactose specificity (Dolichos biflorus agglutinin [DBA], soybean agglutinin [SBA], Sophora japonica agglutinin [SJA], Bandeiraea (Griffonia) simplicifolia lectin I [BSL I], peanut agglutinin [PNA], Artocarpus integrifolia lectin [Jacalin], Ricinus communis agglutinin-1 [RCA-1], Erythrina cristagalli lectin [ECL]). At gastrulation stages, patterns of lectin binding could be distinguished in the epiblast, mesoderm, and endoderm cell layers. The primitive streak failed to bind any of the lectins, but LEA and WGA bound to the epiblast in regions lateral to the streak, indicating the loss of some glucosamine residues medially in preparation for the ingression movements of gastrulation. Several lectins showed marked binding to the mesoderm cells after their passage through the primitive streak; these were LCA, PSA, WGA, sWGA, BSL, and most particularly PNA. Therefore, the epithelial-mesenchymal transformation from epiblast to mesoderm at the primitive streak is accompanied by cell surface oligosaccharide changes in the epiblast and mesoderm that involve all classes of lectins including the PNA-binding sequence Gal beta 1-3GalNAc. Ultrastructurally, PNA was shown to bind extracellularly to matrix fibrils. Jacalin, having the same sugar specificity as PNA, but binding to serine/threonine linked chains rather than asparagine linked chains showed no binding to the mesoderm.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Sustained phosphorylation of MARCKS in differentiating neurogenic regions during chick embryo development.

    PubMed

    Zolessi, F R; Arruti, C

    2001-10-24

    MARCKS, a substrate for several kinases, has critical functions in morphogenetic processes involved in the development of the nervous system. We previously described the purification of MARCKS from chick embryo brain, using a monoclonal antibody (mAb 3C3), raised against embryonic neural retina. Here we show that mAb 3C3 is an antibody sensitive to phosphorylation state. We used it to explore the appearance and developmental progression of phospho-MARCKS (ph-MARCKS) during initial stages of neurogenesis in retina and spinal cord, and compared its distribution with total MARCKS. Before the onset of neural differentiation, MARCKS protein was already accumulated in neural and non-neural embryonic tissues, while ph-MARCKS immunoreactivity was weak, although ubiquitous too. A sudden increase of ph-MARCKS, paralleling a total MARCKS augmentation, was particularly noticeable in the earliest differentiating neurons in the neural retina. Ganglion cells displayed a high ph-MARCKS signal in the soma, as well as in the growing axon. A short time thereafter, a similar increase of ph-MARCKS was present across the entire width of the neural retina, where the differentiation of other neurons and photoreceptors occurs. The increase of ph-MARCKS in cells took place before the detection of the transcription factor Islet-1/2, an early neuronal differentiation molecular marker, in cells of the same region. Analogous phenomena were observed in cervical regions of the spinal cord, where motor neurons were differentiating. Neurogenic regions in the spinal cord contained higher amounts of ph-MARCKS than the floor plate. Taken together, these results strongly suggest that the appearance and relatively long-lasting presence of ph-MARCKS polypeptides are related to specific signaling pathways active during neurogenesis. PMID:11675128

  5. The muscarinic receptor of chick embryo cells: correlation between ligand binding and calcium mobilization

    PubMed Central

    1985-01-01

    In this report we characterize muscarinic cholinergic receptor on embryonic cells. We established dose-response curves by fluorometric measurement of Ca2+ mobilization in cell suspensions of whole chick embryos stage 23/24. Ca2+ mobilization was quantitated by standardization of chlorotetracycline (CTC) fluorescence changes after stimulation with muscarinic agonists. We determined ED50 values for the agonists acetylcholine and carbachol as 3.4 X 10(-6) and 2.7 X 10(-5) M, respectively. Pilocarpine and oxotremorine were found to act as reversible competitive antagonists with inhibition constants (Kl) of 5.0 X 10(-6) and 1.4 X 10(-6) M, respectively. Bethanechol, which induced only 23% of the maximal effect obtained by acetylcholine, was a partial agonist with an ED50 of 4.8 X 10(-4) M. Its antagonistic component is expressed by an inhibition constant of 1.9 X 10(-4) M. In parallel, binding studies were performed in a competition assay with [3H]-quinuclidinylbenzilate. For the agonists acetylcholine and carbachol, binding parameters were best fitted by a "two binding-sites model." Comparison with dose-response curves indicated that Ca2+ mobilization was triggered via the high-affinity binding site. The inhibition constants of antagonists derived from the shift of dose- response curves corresponded to the fitted KD values of the binding studies when a "one binding-site model" was applied. Combination of dose-response and binding data showed close proportionality between receptor occupancy and calcium mobilization. No spare receptors were present. PMID:2858487

  6. Early determination of nasal-temporal retinotopic specificity in the eye anlage of the chick embryo.

    PubMed

    Dütting, D; Thanos, S

    1995-01-01

    The retinotectal projection of the chick is established between Embryonic Days 3 and 13 (E3 to E13). Fate mappings of the eye anlage by local injections of the fluorescent dyes DiI and DiA revealed that the anteroposterior axis of the optic vesicle corresponds to the nasotemporal axis of the retina. To investigate possible alterations in retinotopic specificity after ablating parts of the early eye anlage, we resected either most of the presumptive temporal or a large part of the presumptive nasal half of the eye anlage around stage 11 of the Hamburger-Hamilton scale (40-45 hr). After such treatment, the axes are restored in the healed optic vesicle. In the healing process the wound is closed by cells moving in from surrounding areas. After early posterior (i.e., temporal) ablation, the projection from the restored temporal half-retina onto the optic tectum was examined in embryos (E13 to E17) and juvenile chicken (P16) by retrograde and anterograde labeling of ganglion cells and their axons with DiI and DiASP. Normally, only a small fraction of ganglion cells from the temporal retina (between 6.4% on E13 and 0.08% on P16) projects onto the caudal part of the tectum. In experimental embryos and juvenile chicken this fraction is significantly increased (up to 80%). Retrograde double-labeling from the rostral and the caudal tectum reveals that temporal cells project onto either the rostral or the caudal tectum, but not via collaterals upon both areas. The ganglion cells with "displaced nasal" identity within the temporal retina that were backlabeled from the caudal tectum were to a large extent segregated into distinct clusters, indicating their derivation from few or possibly even single progenitor cells. Likewise, ablation of the anterior half of the optic vesicle led to clusters of rostrally projecting cells of "displaced temporal" identity within the restored nasal retina. In these experiments the dorsal-ventral retinotectal relationship remained intact. The

  7. Neural crest cell migratory pathways in the trunk of the chick embryo.

    PubMed

    Loring, J F; Erickson, C A

    1987-05-01

    Neural crest cells migrate during embryogenesis to give rise to segmented structures of the vertebrate peripheral nervous system: namely, the dorsal root ganglia and the sympathetic chain. However, neural crest cell arise from the dorsal neural tube where they are apparently unsegmented. It is generally agreed that the somites impose segmentation on migrating crest cells, but there is a disagreement about two basic questions: exactly pathways do neural crest cells use to move through or around somites, and do neural crest cells actively migrate or are they passively dispersed by the movement of somite cells? The answers to both questions are critically important to any further understanding of the mechanisms underlying the precise distribution of the neural crest cells that develop into ganglia. We have done an exhaustive study of the locations of neural crest cells in chick embryos during early stages of their movement, using antibodies to neural crest cells (HNK-1), to neural filament-associated protein in growing nerve processes (E/C8), and to the extracellular matrix molecule laminin. Our results show that Some neural crest cells invade the extracellular space between adjacent somites, but the apparent majority move into the somites themselves along the border between the dermatome/myotome (DM) and the sclerotome. Neural crest cells remain closely associated with the anterior half of the DM of developing somites as they travel, suggesting that the basal lamina of the DM may be used as a migratory substratum. Supporting this idea is our observation that the development of the DM basal lamina coincides in time and location with the onset of crest migration through the somite. The leading front of neural crest cells advance through the somite while the length of the DM pathway remains constant, suggesting active locomotion, at least in this early phase of development. Neural crest cells leave the DM at a later stage of development to associate with the dorsal

  8. Culture of domestic cat ovarian tissue in vitro and in the chick embryo chorioallantoic membrane.

    PubMed

    Vilela, J M V; Leonel, E C R; D'Oliveira, L; Paiva, R E G; Miranda-Vilela, A L; Amorim, C A; Pic-Taylor, A; Lucci, C M

    2016-10-15

    In vitro culture and transplantation procedures are essential protocols employed in the evaluation of ovarian follicle survival and development. Culture in the chorioallantoic membrane (CAM) of chick embryos is an intermediate method that provides important follicle development information and has not been tested for cat ovaries to date. The aim of this study was to investigate if in vitro and CAM culture could be used as short-term systems to study cat ovarian tissue development. The ovaries of eight cats were dissected into 3-mm(3) cubes, cultured in vitro and in CAM for up to 5 days, and stained with hematoxylin-eosin and Gomori trichrome. Cell proliferation was analyzed using anti-Ki67. Possible differences among groups were investigated by analysis of variance or the Kruskal-Wallis test followed by Bonferroni correction. The T-test or Wilcoxon test was used to verify differences between the CAM and IVC. Results revealed that 87.5% of all follicles were primordial during culture. The percentage of primordial follicles in the morphologically normal follicles (MNF) pool was always higher than 80%, with the exception of Day 3 of CAM culture, but the number of MNF reduced significantly from Day 0 (600 out of 777 follicles) to Day 5 in the CAM (91 out of 171) and IVC (296 out of 686). The number of primordial follicles in 1 mm(3) in Days 2, 3, and 5 in the CAM was significantly lower than that in the control (Day 0). No cellular proliferation was observed in culture. Vascularization occurred in the CAM culture, but with no association to follicular viability. In addition, both methods showed an increase in connective tissue during culture. Although no significant differences were observed in the percentage of MNF, there was a reduction in the total number of follicles, both for IVC and CAM-cultured ovarian tissue. Furthermore, anti-Ki67 did not stain any follicle after Day 0 in IVC or in CAM culture. Neither system was capable of promoting follicle growth and

  9. Relationship between spatially restricted Krox-20 gene expression in branchial neural crest and segmentation in the chick embryo hindbrain.

    PubMed Central

    Nieto, M A; Sechrist, J; Wilkinson, D G; Bronner-Fraser, M

    1995-01-01

    Previous studies have suggested that the rostrocaudal patterning of branchial arches in the vertebrate embryo derives from a coordinate segmental specification of gene expression in rhombomeres (r) and neural crest. However, expression of the Krox-20 gene is restricted to neural crest cells migrating to the third branchial arch, apparently from r5, whereas this rhombomere contributes cells to both the second and third arches. We examined in the chick embryo how this spatially restricted expression is established. Expression occurs in precursors in both r5 and r6, and we show by cell labelling that both rhombomeres contribute to Krox-20-expressing neural crest, emigration occurring first from r6 and later caudally from r5. Krox-20 transcripts are not detected in some precursors in rostral r5, presaging the lack of expression in cells migrating rostrally from this rhombomere. After transposition of r6 to the position of r4 or r5, many Krox-20-expressing cells migrate rostral to the otic vesicle, whereas when r5 is transplanted to the position of r4, only a small number of migrating cells express Krox-20. These results indicate that, in the chick, Krox-20 expression in branchial neural crest does not correlate with rhombomeric segmentation, and that there may be intrinsic differences in regulation between the r5 and r6 Krox-20-expressing populations. Images PMID:7537662

  10. Chick embryo chorioallantoic membrane (CAM): an alternative predictive model in acute toxicological studies for anti-cancer drugs

    PubMed Central

    KUE, Chin Siang; TAN, Kae Yi; LAM, May Lynn; LEE, Hong Boon

    2015-01-01

    The chick embryo chorioallantoic membrane (CAM) is a preclinical model widely used for vascular and anti-vascular effects of therapeutic agents in vivo. In this study, we examine the suitability of CAM as a predictive model for acute toxicology studies of drugs by comparing it to conventional mouse and rat models for 10 FDA-approved anticancer drugs (paclitaxel, carmustine, camptothecin, cyclophosphamide, vincristine, cisplatin, aloin, mitomycin C, actinomycin-D, melphalan). Suitable formulations for intravenous administration were determined before the average of median lethal dose (LD50) and median survival dose (SD50) in the CAM were measured and calculated for these drugs. The resultant ideal LD50 values were correlated to those reported in the literature using Pearson’s correlation test for both intravenous and intraperitoneal routes of injection in rodents. Our results showed moderate correlations (r2=0.42 − 0.68, P<0.005–0.05) between the ideal LD50 values obtained using the CAM model with LD50 values from mice and rats models for both intravenous and intraperitoneal administrations, suggesting that the chick embryo may be a suitable alternative model for acute drug toxicity screening before embarking on full toxicological investigations in rodents in development of anticancer drugs. PMID:25736707

  11. Chick embryo chorioallantoic membrane (CAM): an alternative predictive model in acute toxicological studies for anti-cancer drugs.

    PubMed

    Kue, Chin Siang; Tan, Kae Yi; Lam, May Lynn; Lee, Hong Boon

    2015-01-01

    The chick embryo chorioallantoic membrane (CAM) is a preclinical model widely used for vascular and anti-vascular effects of therapeutic agents in vivo. In this study, we examine the suitability of CAM as a predictive model for acute toxicology studies of drugs by comparing it to conventional mouse and rat models for 10 FDA-approved anticancer drugs (paclitaxel, carmustine, camptothecin, cyclophosphamide, vincristine, cisplatin, aloin, mitomycin C, actinomycin-D, melphalan). Suitable formulations for intravenous administration were determined before the average of median lethal dose (LD50) and median survival dose (SD(50)) in the CAM were measured and calculated for these drugs. The resultant ideal LD(50) values were correlated to those reported in the literature using Pearson's correlation test for both intravenous and intraperitoneal routes of injection in rodents. Our results showed moderate correlations (r(2)=0.42 - 0.68, P<0.005-0.05) between the ideal LD(50) values obtained using the CAM model with LD(50) values from mice and rats models for both intravenous and intraperitoneal administrations, suggesting that the chick embryo may be a suitable alternative model for acute drug toxicity screening before embarking on full toxicological investigations in rodents in development of anticancer drugs. PMID:25736707

  12. Learning about Vertebrate Limb Development

    ERIC Educational Resources Information Center

    Liang, Jennifer O.; Noll, Matthew; Olsen, Shayna

    2014-01-01

    We have developed an upper-level undergraduate laboratory exercise that enables students to replicate a key experiment in developmental biology. In this exercise, students have the opportunity to observe live chick embryos and stain the apical ectodermal ridge, a key tissue required for development of the vertebrate limb. Impressively, every…

  13. The effects of thermal manipulations during embryogenesis of broiler chicks on growth of embryo and skeletal traits

    NASA Astrophysics Data System (ADS)

    Aygün, Ali; Narinç, Doǧan

    2016-04-01

    Incubation temperature is one of the important environmental factors that can induce epigenetic thermal adaptation of different physiological control systems. Thus, post hatch thermo tolerance ability of birds may be gained using these manipulations during different incubation periods. The current study was carried out to reveal the effects of temperature manipulations during early and late embryogenesis on weight of embryo and size of skeletal bilateral traits (face, wings, metatarsus, tibia, and femur) in broiler chicken embryos. One thousand commercial broiler eggs from 46 week old breeder flock were used in study. Treatments consisted of eggs incubated at 37.8°C and 55% relative humidity throughout (control; DG1), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 0 to 8 (DG2), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 10 to 18 (DG3), heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 8 to 10 (DG4), and heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 16 to 18 (DG5). Measurements of embryo weight and bilateral traits were obtained at 20 day of incubation and at hatch (at day 21). It was determined that the live weights of embryo and chick were affected significantly by treatment; DG3 group has shown higher mean values than the other treatment groups (P<0.05). There were differences in lengths of femur, tibia and metatarsus among treatment groups at hatch. Particularly, the high incubator temperatures at the second half of incubation accelerated growth of body and bone in embryos. These consequences of the treatments performed at different temperatures and times indicate that the different metabolic shifts realized by the embryos.

  14. Dual Labeling of Neural Crest Cells and Blood Vessels Within Chicken Embryos Using ChickGFP Neural Tube Grafting and Carbocyanine Dye DiI Injection

    PubMed Central

    Delalande, Jean-Marie; Thapar, Nikhil; Burns, Alan J.

    2015-01-01

    All developing organs need to be connected to both the nervous system (for sensory and motor control) as well as the vascular system (for gas exchange, fluid and nutrient supply). Consequently both the nervous and vascular systems develop alongside each other and share striking similarities in their branching architecture. Here we report embryonic manipulations that allow us to study the simultaneous development of neural crest-derived nervous tissue (in this case the enteric nervous system), and the vascular system. This is achieved by generating chicken chimeras via transplantation of discrete segments of the neural tube, and associated neural crest, combined with vascular DiI injection in the same embryo. Our method uses transgenic chickGFP embryos for intraspecies grafting, making the transplant technique more powerful than the classical quail-chick interspecies grafting protocol used with great effect since the 1970s. ChickGFP-chick intraspecies grafting facilitates imaging of transplanted cells and their projections in intact tissues, and eliminates any potential bias in cell development linked to species differences. This method takes full advantage of the ease of access of the avian embryo (compared with other vertebrate embryos) to study the co-development of the enteric nervous system and the vascular system. PMID:26065540

  15. Dual labeling of neural crest cells and blood vessels within chicken embryos using Chick(GFP) neural tube grafting and carbocyanine dye DiI injection.

    PubMed

    Delalande, Jean-Marie; Thapar, Nikhil; Burns, Alan J

    2015-05-28

    All developing organs need to be connected to both the nervous system (for sensory and motor control) as well as the vascular system (for gas exchange, fluid and nutrient supply). Consequently both the nervous and vascular systems develop alongside each other and share striking similarities in their branching architecture. Here we report embryonic manipulations that allow us to study the simultaneous development of neural crest-derived nervous tissue (in this case the enteric nervous system), and the vascular system. This is achieved by generating chicken chimeras via transplantation of discrete segments of the neural tube, and associated neural crest, combined with vascular DiI injection in the same embryo. Our method uses transgenic chick(GFP) embryos for intraspecies grafting, making the transplant technique more powerful than the classical quail-chick interspecies grafting protocol used with great effect since the 1970s. Chick(GFP)-chick intraspecies grafting facilitates imaging of transplanted cells and their projections in intact tissues, and eliminates any potential bias in cell development linked to species differences. This method takes full advantage of the ease of access of the avian embryo (compared with other vertebrate embryos) to study the co-development of the enteric nervous system and the vascular system.

  16. Evidence against a direct role for oxidative stress in cadmium-induced axial malformation in the chick embryo

    SciTech Connect

    Thompson, Jennifer; Doi, Takashi; Power, Eoin; Balasubramanian, Ishwarya; Puri, Prem; Bannigan, John

    2010-03-15

    Cadmium (Cd) is a powerful inducer of oxidative stress. It also causes ventral body wall defects in chick embryos treated at Hamburger-Hamilton stages 16-17. By measuring malondialdehyde levels (TBARS method) and cotreating with antioxidants (tempol, ascorbate, and N-acetylcysteine), we sought to determine if oxidative stress were directly related to teratogenesis. We also investigated the expression of mRNAs for antioxidant enzymes superoxide dismutase (SOD) -1 and -2, catalase (CAT), and glutathione peroxidase (GPx). RT-PCR showed reductions in SOD-1, SOD-2, and CAT 1 hour after treatment with Cd. MDA levels increased 4 hours after Cd, and remained elevated 24 hours after treatment. Of the antioxidants, only N-acetylcysteine reduced MDA levels to control values. Nonetheless, no antioxidant could reduce embryo lethality or malformation rates. Furthermore, MDA levels 24 hours after treatment were identical in malformed and normal embryos exposed to Cd. Hence, we conclude that oxidative stress may not have a direct role in Cd teratogenesis.

  17. Simultaneous real-time quantification of blood flow and vascular growth in the chick embryo using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Kowalski, William J.; Teslovich, Nikola C.; Chen, Chia-Yuan; Keller, Bradley B.; Pekkan, Kerem

    2014-03-01

    Experimental and clinical data indicate that hemodynamic forces within the embryo provide critical biomechanical cues for cardiovascular morphogenesis, growth, and remodeling and that perturbed flow is a major etiology of congenital heart disease. However, embryonic flow-growth relationships are largely qualitative and poorly defined. In this work, we provide a quantitative analysis of in vivo flow and growth trends in the chick embryo using optical coherence tomography (OCT) to acquire simultaneous velocity and structural data of the right vitelline artery continuously over a ten hour period beginning at stage 16 (hour 54). We obtained 3D vessel volumes (15 μm lateral, 4.3 μm axial resolutions, 6 μm slice spacing) at 60 minute intervals, taking a B-scan time series totaling one cardiac cycle at each slice. Embryos were maintained at a constant 37°C and 60% humidity during the entire acquisition period through an inhouse built chamber. The 3D vessel lumen geometries were reconstructed manually to assess growth. Blood flow velocity was computed from the central B-scan using red blood cell particle image velocimetry. The use of extended OCT imaging as a non-invasive method for continuous and simultaneous flow and structural data can enhance our understanding of the biomechanical regulation of critical events in morphogenesis. Data acquired will be useful to validate predictive finite-element 3D growth models.

  18. Improvements in histological quality and signal retention following in situ hybridization in early chick embryos using plastic resin and recolorization.

    PubMed

    Sawitzke, A L; Chapman, S C; Bleyl, S B; Schoenwolf, G C

    2005-01-01

    We describe a novel method that allows reliable detection of in situ hybridization signals in thin sections of plastic embedded embryos. Sections from plastic embedded embryos are thinner and have superior histological quality compared to paraffin, gelatin, agarose embedded sections or cryosections; however, plastic resin traditionally has not been used as an embedding medium following in situ hybridization because of loss of signal. When signal is detected with alkaline phosphatase and NBT/BCIP, the resulting colored precipitate is subject to fading when samples are exposed to organic compounds. The colored precipitate can be redeposited by repeating the NBT/BCIP reaction following plastic sectioning. This recolorization shows no loss of specificity, because signal is detected only where the anti-digoxigenin/alkaline phosphatase conjugated antibody is bound to the riboprobe. Strong signals can be detected without recolorization; however, weaker signals require the recolorization step. This novel method of re-depositing colored precipitate after processing and sectioning allows accurate determination of the location of gene expression and study of this expression in high quality histological sections of early chick embryos.

  19. Studies on the mechanism of retinoid-induced pattern duplications in the early chick limb bud: temporal and spatial aspects

    PubMed Central

    1985-01-01

    All-trans-retinoic acid causes striking digit pattern changes when it is continuously released from a bead implanted in the anterior margin of an early chick wing bud. In addition to the normal set of digits (234), extra digits form in a mirror-symmetrical arrangement, creating digit patterns such as a 432234. These retinoic acid-induced pattern duplications closely mimic those found after grafts of polarizing region cells to the same positions with regard to dose-response, timing, and positional effects. To elucidate the mechanism by which retinoic acid induces these pattern duplications, we have studied the temporal and spatial distribution of all-trans-retinoic acid and its potent analogue TTNPB in these limb buds. We find that the induction process is biphasic: there is an 8-h lag phase followed by a 6-h duplication phase, during which additional digits are irreversibly specified in the sequence digit 2, digit 3, digit 4. On average, formation of each digit seems to require between 1 and 2 h. The tissue concentrations, metabolic pattern, and spatial distribution of all- trans-retinoic acid and TTNPB in the limb rapidly reach a steady state, in which the continuous release of the retinoid is balanced by loss from metabolism and blood circulation. Pulse-chase experiments reveal that the half-time of clearance from the bud is 20 min for all-trans- retinoic acid and 80 min for TTNPB. Manipulations that change the experimentally induced steep concentration gradient of TTNPB suggest that a graded distribution of retinoid concentrations across the limb is required during the duplication phase to induce changes in the digit pattern. The extensive similarities between results obtained with retinoids and with polarizing region grafts raise the possibility that retinoic acid serves as a natural "morphogen" in the limb. PMID:4055899

  20. Detection of Marek's disease virus serotype 1 (MDV1) glycoprotein D in MDV1-infected chick embryo fibroblasts.

    PubMed

    Ono, M; Jang, H K; Maeda, K; Kawaguchi, Y; Tohya, Y; Niikura, M; Mikami, T

    1996-08-01

    Chick embryo fibroblasts (CEFs) infected with three strains of Marek's disease virus serotype 1 (MDV1), GA, Md5 and JM, were subjected to indirect immunofluorescence assay with monoclonal antibodies (MAbs) against MDV1 homolog of glycoprotein D (MDV1 gD) of herpes simplex virus. By the MAbs, a number of MDV1 gD-positive cells were detected in CEFs infected with GA, whereas only a few and no positive cells were detected in CEFs infected with Md5 and JM, respectively. The MDV1 gD in GA-infected CEFs was recognized as the band of 64 kDa in immunoblot analysis using one of the MAbs. This is the first report that the MDV1 gD was detected in MDV1-infected cell cultures.

  1. Neurturin-GFRalpha2 signaling controls liver bud migration along the ductus venosus in the chick embryo.

    PubMed

    Tatsumi, Norifumi; Miki, Rika; Katsu, Kenjiro; Yokouchi, Yuji

    2007-07-01

    During chick liver development, the liver bud arises from the foregut, invaginates into the septum transversum, and elongates along and envelops the ductus venosus. However, the mechanism of liver bud migration is only poorly understood. Here, we demonstrate that a GDNF family ligand involved in neuronal outgrowth and migration, neurturin (NRTN), and its receptor, GFRalpha2, are essential for liver bud migration. In the chick embryo, we found that GFRalpha2 was expressed in the liver bud and that NRTN was expressed in the endothelial cells of the ductus venosus. Inhibition of GFRalpha2 signaling suppressed liver bud elongation along the ductus venous without affecting cell proliferation and apoptosis. Moreover, ectopic expression of NRTN perturbed the directional migration along the ductus venosus, leading to splitting or ectopic branching of the liver. We showed that liver buds selectively migrated toward an NRTN-soaked bead in vitro. These data represent a new model for liver bud migration: NRTN secreted from endothelial cells functions as a chemoattractant to direct the migration of the GFRalpha2-expressing liver bud in early liver development.

  2. Time-dependent inactivation of chick-embryo prolyl 4-hydroxylase by coumalic acid. Evidence for a syncatalytic mechanism.

    PubMed Central

    Günzler, V; Hanauske-Abel, H M; Myllylä, R; Mohr, J; Kivirikko, K I

    1987-01-01

    From the structure-activity relationships of known competitive inhibitors, coumalic acid (2-oxo-1,2H-pyran-5-carboxylic acid) was deduced to be a potential syncatalytic inhibitor for chick-embryo prolyl 4-hydroxylase. The compound caused time-dependent inactivation, the reaction rate being first-order. The inactivation constant was 0.094 min-1, the Ki 17 mM and the bimolecular rate constant 0.09 M-1 X S-1. Human prolyl 4-hydroxylase and chick embryo lysyl hydroxylase were also inactivated, though to a lesser extent. Inactivation could be prevented by adding high concentrations of 2-oxoglutarate or its competitive analogues to the reaction mixture. In Lineweaver-Burk kinetics, coumalic acid displayed S-parabolic competitive inhibition with respect to 2-oxoglutarate. The inactivation reaction had cofactor requirements similar to those for the decarboxylation of 2-oxoglutarate. Enzymic activity was partially preserved in the absence of iron, but the rescue was incomplete, owing to decreased stability of the enzyme under this condition. Coumalic acid also decreased the electrophoretic mobility of the alpha-subunit, but the beta-subunit was not affected. Prolonged incubation of coumalic acid above pH 6.8 led to loss of its inactivating potency, owing to hydrolysis. It is concluded that the inactivation of prolyl 4-hydroxylase by coumalic acid is due to a syncatalytic mechanism. The data also suggest that the 2-oxoglutarate-binding site of the enzyme is located within the alpha-subunit. PMID:3036081

  3. FGF2 plays a key role in embryonic cerebrospinal fluid trophic properties over chick embryo neuroepithelial stem cells.

    PubMed

    Martín, C; Bueno, D; Alonso, M I; Moro, J A; Callejo, S; Parada, C; Martín, P; Carnicero, E; Gato, A

    2006-09-15

    During early stages of brain development, neuroepithelial stem cells undergo intense proliferation as neurogenesis begins. Fibroblast growth factor 2 (FGF2) has been involved in the regulation of these processes, and although it has been suggested that they work in an autocrine-paracrine mode, there is no general agreement on this because the behavior of neuroepithelial cells is not self-sufficient in explants cultured in vitro. In this work, we show that during early stages of development in chick embryos there is another source of FGF2, besides that of the neuroepithelium, which affects the brain primordium, since the cerebrospinal fluid (E-CSF) contains several isoforms of this factor. We also demonstrate, both in vitro and in vivo, that the FGF2 from the E-CSF has an effect on the regulation of neuroepithelial cell behavior, including cell proliferation and neurogenesis. In order to clarify putative sources of FGF2 in embryonic tissues, we detected by in situ hybridization high levels of mRNA expression in notochord, mesonephros and hepatic primordia, and low levels in brain neuroectoderm, corroborated by semiquantitative PCR analysis. Furthermore, we show that the notochord segregates several FGF2 isoforms which modify the behavior of the neuroepithelial cells in vitro. In addition, we show that the FGF2 ligand is present in the embryonic serum; and, by means of labeled FGF2, we prove that this factor passes via the neuroepithelium from the embryonic serum to the E-CSF in vivo. Considering all these results, we propose that, in chick embryos, the behavior of brain neuroepithelial stem cells at the earliest stages of development is influenced by the action of the FGF2 contained within the E-CSF which could have an extraneural origin, thus suggesting a new and complementary way of regulating brain development. PMID:16916506

  4. Neurotoxicological effects of nicotine on the embryonic development of cerebellar cortex of chick embryo during various stages of incubation.

    PubMed

    El-Beltagy, Abd El-Fattah B M; Abou-El-Naga, Amoura M; Sabry, Dalia M

    2015-10-01

    Long-acting nicotine is known to exert pathological effects on almost all tissues including the cerebellar cortex. The present work was designed to elucidate the effect of nicotine on the development of cerebellar cortex of chick embryo during incubation period. The fertilized eggs of hen (Gallus gallus domesticus) were injected into the air space by a single dose of long acting nicotine (1.6 mg/kg/egg) at the 4th day of incubation. The embryos were taken out of the eggs on days 8, 12 and 16 of incubation. The cerebellum of the control and treated embryos at above ages were processed for histopathological examination. The TEM were examined at 16th day of incubation. The results of the present study revealed that, exposure to long-acting nicotine markedly influence the histogenesis of cerebellar cortex of chick embryo during the incubation period. At 8th day of incubation, nicotine delayed the differentiation of the cerebellar analge; especially the external granular layer (EGL) and inner cortical layer (ICL). Furthermore, at 12th day of incubation, the cerebellar foliation was irregular and the Purkinje cells not recognized. By 16th day of incubation, the cerebellar foliations were irregular with interrupted cerebellar cortex and irregular arrangement of Purkinje cells. Immunohistochemical analysis for antibody P53 protein revealed that the cerebellar cortex in all stages of nicotine treated groups possessed a moderate to weak reaction for P53 protein however; this reaction was markedly stronger in the cerebellar cortex of control groups. Moreover, the flow cytometric analysis confirmed that the percentage of apoptosis in control group was significantly higher compared with that of nicotine treated group. At the TEM level, the cerebellar Purkinje cells of 16th day of treated groups showed multiple subcellular alterations in compared with those of the corresponding control group. Such changes represented by appearing of vacuolated mitochondria, cisternal

  5. THE RELATION BETWEEN THE INTRACELLULAR RIBONUCLEIC ACID DISTRIBUTION AND AMINO ACID INCORPORATION IN THE LIVER OF THE DEVELOPING CHICK EMBRYO

    PubMed Central

    Duck-Chong, Coral; Pollak, J. K.; North, R. J.

    1964-01-01

    The RNA-P and DNA-P content of the nucleus and the RNA-P content of the whole cell of the livers of 8- to 20-day chick embryos and of adult fowls have been determined. The DNA-P content of the liver nuclei was slightly higher in the 8- and 10-day embryo than in all the other stages examined. A significant decrease in the RNA content of the cell occurred during embryonic development. The RNA content of the adult cell was the same as that of the 14- to 16-day embryo. The proportion of the cellular RNA contributed by the nucleus also decreased during development. In respect to both nuclear RNA content and distribution of RNA between nucleus and cytoplasm, the adult resembled the 8- to 12-day embryo. Examination of the fine structure of the cell showed that, as development progressed, free ribosomes decreased in number and the rough membranes increased. Slices of 8-, 14-, and 20-day embryonic livers and of adult livers were incubated with 14C-leucine, and the amount of labeled amino acid incorporated into whole tissue protein and into the proteins of the subcellular fractions was measured. Embryonic liver incorporated 14C-leucine 15 to 30 times more rapidly than adult liver. The microsomal protein was always more highly labelled than the protein in any other subcellular fraction; however, in the 8-day embryonic and the adult liver the proportion of total counts found in the nuclear fraction was considerably higher than in the 14- or 20-day embryonic liver. The significance of an apparent correlation between the proportion of the cell's RNA contributed by the nucleus and the proportion of total counts in the nuclear fraction is discussed. PMID:14105214

  6. Identification and characterization of subpopulations of Pax3 and Pax7 expressing cells in developing chick somites and limb buds

    PubMed Central

    Galli, Lisa M.; Barnes, Tiffany L.; Knight, Sara R.; Doak, Allison K.; Kadzik, Rachel S.; Burrus, Laura W.

    2010-01-01

    Pax3 and Pax7 are closely related paired-boxed family transcription factors that are known to play important roles in embryonic and adult myogenesis. Previous reports describing the expression of Pax3 and Pax7 transcripts reveal expression in many overlapping domains. In this manuscript, we extend these studies by examining the protein expression profiles for Pax3 and Pax7 in developing chick somites and limbs with cellular resolution. Our studies show the existence of distinct subpopulations of cells in the somite and developing limb that are defined by the relative expression levels of Pax3 and Pax7. We also show that Pax3 and Pax7 negatively regulate each other's expression in the dermomyotome, thus providing a possible mechanism for the maintenance of observed expression patterns in the dermomyotome. Further characterization of Pax3 and/or Pax7 positive cells in the dermomyotome and myotome with respect to proliferation and differentiation reveals subpopulations of cells with distinct properties. PMID:18521946

  7. Triploidy and haploid-triploid mosaicism among chick embryos (Gallus domesticus).

    PubMed

    Zartman, D L; Smith, A L

    1975-01-01

    Homomorphic, chromosomally abnormal roosters were mated to normal hens. The 23 hens produced 67 embryos, including two triploids and a haploid-triploid mosaic at about 26 hours of incubation. Both of the triploid embryos were conceived within a 5-day period. The presence of a single genome of paternal origin with marker chromosomes in each triploid led to the conclusion that these embryos were derived from diploid, ZW-type ova fertilized by haploid, Z-type spermatozoa. The inheritance pattern of the mosaic embryo was clearly due to a spermatozoal origin for the haploid cell line; and one genome of the three in the triploid cell line was paternal. The sec chromosomes were Z/ZZZ, with one Z of each cell line being a translocation product of paternal derivation. PMID:1192842

  8. Detection in chick embryo of fetoproteins not recognized by the dam's immune system and of soluble alloantigens. Presumptive teratogenic and abortogenic capacity of their specific IgY

    PubMed Central

    Rodríguez-Burgos, Antonio

    2003-01-01

    Background The aim of this work was to detect antigens, non-self to the dam, potentially present in chick embryo prior to organogenesis with a view to establishing the consequences of their neutralization on chick development. To this end, hens were immunized with the extract from embryos incubated for 53 h. Their eggs were either used to isolate immunoglobulins for dot and blot tests or incubated for variable lengths of time. Results Immunoblot tests, using adsorbed primary and secondary antibodies against paternal serum, revealed the presence of at least four antigens of 32, 34, 70 and 200 kDa that can be classified as soluble alloantigens. The same antibodies against chick embryo extracts (between 53 h and 9) showed at least five aged antigens of 34, 52, 90, 200 and 250 kDa, not detected in cock serum, that can thus be considered as soluble, foreign to the immunized hens and transitory antigens. The abnormalities observed included arrested development and fetal death, as well as minor functional damage in the few chicks that were born alive. The ratio of abnormal to normal embryos was 2.85 in the experimental group and 0.43 in the control group. With regard to congenital anomalies it must be said that of the 81 eggs incubated only four chicks were born alive, and of these, only one had a healthy birth and subsequent growth. The other three showed a transitory ataxia and one of them presented adult lumbar scoliosis and asymmetric pelvis. Conclusions The problem of recurrent spontaneous abortions is revisited in the light of these results. Some recent data suggest that soluble alloantigens may be candidates for a new etiological entity in recurrent spontaneous abortions. They can also be the cause of some congenital anomalies. The soluble, foreign, transitory antigens may have a similar effect although there is no supportive data in the literature. PMID:12831405

  9. The chick embryo as a model for the effects of prenatal exposure to alcohol on craniofacial development.

    PubMed

    Kiecker, Clemens

    2016-07-15

    Prenatal exposure to ethanol results in fetal alcohol spectrum disorder (FASD), a syndrome characterised by a broad range of clinical manifestations including craniofacial dysmorphologies and neurological defects. The characterisation of the mechanisms by which ethanol exerts its teratogenic effects is difficult due to the pleiotropic nature of its actions. Different experimental model systems have been employed to investigate the aetiology of FASD. Here, I will review studies using these different model organisms that have helped to elucidate how ethanol causes the craniofacial abnormalities characteristic of FASD. In these studies, ethanol was found to impair the prechordal plate-an important embryonic signalling centre-during gastrulation and to negatively affect the induction, migration and survival of the neural crest, a cell population that generates the cartilage and most of the bones of the skull. At the cellular level, ethanol appears to inhibit Sonic hedgehog signalling, alter levels of retionoic acid activity, trigger a Ca(2+)-CamKII-dependent pathway that antagonises WNT signalling, affect cytoskeletal dynamics and increase oxidative stress. Embryos of the domestic chick Gallus gallus domesticus have played a central role in developing a working model for the effects of ethanol on craniofacial development because they are easily accessible and because key steps in craniofacial development are particularly well established in the avian embryo. I will finish this review by highlighting some potential future avenues of fetal alcohol research. PMID:26777098

  10. Effects of maternal dietary manganese and incubation temperature on hatchability, antioxidant status, and expression of heat shock proteins in chick embryos.

    PubMed

    Zhu, Y W; Lu, L; Li, W X; Zhang, L Y; Ji, C; Lin, X; Liu, H C; Odle, J; Luo, X G

    2015-12-01

    To investigate whether supplementing manganese (Mn) to the maternal diet could reduce the deleterious effect of heat stress on the developing embryo, the hatchability, antioxidant status, and expression of heat shock proteins (HSP) were evaluated in chick embryos under normal and high incubation temperatures. A completely randomized design ( = 6) with 2 maternal dietary Mn treatments (unsupplemented control basal diet versus the basal diet + 120 mg Mn/kg as inorganic Mn) × 2 incubation temperatures (normal, 37.8°C, versus high, 39.0°C) was used. High incubation temperature did not affect ( > 0.19) hatchability and embryo mortality and development but did increase ( < 0.05) activities of heart manganese superoxide dismutase (MnSOD) and liver copper zinc superoxide dismutase and liver MnSOD mRNA and protein levels in embryos. High incubation temperature also decreased ( < 0.003) HSP70 protein level in the heart but had no effects ( > 0.07) in the liver of embryos. Maternal diet with Mn supplementation not only increased ( < 0.05) the hatchability and Mn content ( < 0.001) in the yolk and embryonic tissues and the activity of MnSOD in the heart ( < 0.004) as well as relative liver weight ( < 0.05) under normal incubation temperature but also decreased ( ≤ 0.05) embryo mortality and HSP90 mRNA level in the liver and heart of embryos. Furthermore, under high incubation temperature, maternal diet Mn supplementation increased ( < 0.002) MnSOD protein expression in the liver of embryos but had no effect ( > 0.43) under normal incubation temperature. These results indicated that high incubation temperature induced self-protective responses of chick embryos with a modification of antioxidant status and a depression of HSP70 protein level. Maternal dietary supplementation of Mn could improve the hatchability as well as antioxidant ability to protect against heat challenge in embryos during incubation.

  11. Rediscovering the chick embryo as a model to study retinal development

    PubMed Central

    2012-01-01

    The embryonic chick occupies a privileged place among animal models used in developmental studies. Its rapid development and accessibility for visualization and experimental manipulation are just some of the characteristics that have made it a vertebrate model of choice for more than two millennia. Until a few years ago, the inability to perform genetic manipulations constituted a major drawback of this system. However, the completion of the chicken genome project and the development of techniques to manipulate gene expression have allowed this classic animal model to enter the molecular age. Such techniques, combined with the embryological manipulations that this system is well known for, provide a unique toolkit to study the genetic basis of neural development. A major advantage of these approaches is that they permit targeted gene misexpression with extremely high spatiotemporal resolution and over a large range of developmental stages, allowing functional analysis at a level, speed and ease that is difficult to achieve in other systems. This article provides a general overview of the chick as a developmental model focusing more specifically on its application to the study of eye development. Special emphasis is given to the state of the art of the techniques that have made gene gain- and loss-of-function studies in this model a reality. In addition, we discuss some methodological considerations derived from our own experience that we believe will be beneficial to researchers working with this system. PMID:22738172

  12. Cell death during the development of the truncus and conus of the chick embryo heart.

    PubMed Central

    Hurle, J M; Ojeda, J L

    1979-01-01

    The presence of cell death in the walls of the truncus and conus of the developing chick heart was investigated by a variety of light and electron microscopic techniques. Necrotic areas were observed in the myocardial layer of the truncus and conus and within the mesenchymal cells of the truncoconal ridges and aortopulmonary septum. These necrotic zones appeared first at Stage 25-26 and reached their maximum extent at Stages 29-32 undergoing later progressive disappearance. The morphological changes of the degenerating cells detectable under both transmission and scanning electron microscopy are also reported. The possible role of cell death in the morphogenesis of the truncus and conus is discussed. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 PMID:500497

  13. Bendiocarb effect on liver and central nervous system in the chick embryo.

    PubMed

    Petrovova, Eva; Sedmera, David; Lesnik, Frantisek; Luptakova, Lenka

    2009-05-01

    The aim of the study was to investigate toxicity of bendiocarb (2, 3-isopropyledene-dioxyphenyl methylcarbamate) to organs of chicken embryo. The toxic action of bendiocarb was observed on liver and central nervous system (CNS). Bendiocarb was administered to chicken embryos at embryonic day (ED) 3 in a dose 500 microg/egg and 10 ED (800 microg/egg). The observations showed no macroscopic or microscopic changes in the liver and CNS with either dose or day of incubation when the bendiocarb was administered. The liver and CNS were also investigated for caspase activity in relation to application of bendiocarb and no differences in the number of cells with caspase immunopositivity were observed in comparison with the control. The results obtained indicate that bendiocarb administered in the respective doses showed no toxicity to investigated organs. Furthermore, both at the early (3 ED) and the later (10 ED) stages of development no increase in numbers of apoptotic cells in chicken embryos was observed. PMID:19365755

  14. Effects of serum, tissue extract, conditioned medium, and culture substrata on neurite appearance from spinal cord explants of chick embryo.

    PubMed

    Tanaka, H; Sakai, M; Obata, K

    1982-07-01

    The effects of serum, tissue extracts, conditioned medium, (CM), and culture substrata on neurite appearance from spinal cord explants of 6- to 8-day-old chick embryos were investigated. In Eagle's minimum essential medium (MEM) with no supplement neurites from explants did not appear on collagen coating but on polyornithine coating (PORN). It is concluded that cell-to-substratum interaction is important in neurite appearance. CM, serum and tissue extract potentiated neurite appearance, but their activities were highly dependent on the coating. The amount of collagen was also crucial. On collagen, neurite appearance was observed only when promoting substances were present. CM and serum contained at least two components; one affected neurite appearance after deposition on collagen and the other affected neurite appearance when present in the culture medium. The former was included also in tissue extracts. Both of adsorbable and non-adsorbable components from any origin were necessary for effective induction of neurite appearance. Heat treatment and dialysis differentiated these active components. On PORN, CM highly potentiated neurite appearance. The activity of the CM was reproduced by its low molecular weight fraction. Serum also promoted neurite appearance, but to a lesser extent than CM. The effect of tissue extract was not remarkable.

  15. Changes in the protein spectrum of the chick embryo mesonephros and metanephros in the course of development.

    PubMed

    Friebová-Zemanová, Z; Schakhmatova, J; Szarska, E; Kopecký, J; Houstĕk, J; Drahota, Z

    1987-01-01

    The protein spectra of two fractions (the soluble and the membrane fraction) of chick embryo kidney homogenates were isolated by electrophoresis on polyacrylamide gels with the aim of detecting the kidney differentiation process at the molecular level and, at the same time, of evaluating similarities in the construction of the mesonephros and metanephros at this level. Corresponding stages of the above two types of kidney were chosen for studying changes in protein structure during differentiation--i.e. the outset of differentiation (the 6-day mesonephros, the 11-day metanephros) and the stage of full maturity (the 14-day mesonephros, the 20-day metanephros). A total of 36 proteins was distinguished. The analysis of the protein spectra showed that the number of proteins changes but slightly during differentiation; the protein composition of the two types of kidney during differentiation altered by 20-35% of the total number of proteins; the similarity of the protein composition of the corresponding stages of mesonephros and metanephros, expressed as the proportion of the number of identical proteins, was greater than the mutual similarity of different developmental stages of the same type of kidney. The percentage of different proteins at corresponding stages of the kidneys varied from 5% to 23% of the total number of proteins detected.

  16. Fractal analysis of extra-embryonic vessels of chick embryos under the effect of glucosamine and chondroitin sulfates.

    PubMed

    de Souza Lins Borba, Fernanda Katharine; Felix, Giovanni Loos Queiroz; Costa, Edbhergue Ventura Lola; Silva, Lisie; Dias, Paulo Fernando; de Albuquerque Nogueira, Romildo

    2016-05-01

    Like heparan sulfate proteoglycans, some monosaccharides and glycosaminoglycans, such as sulfated glucosamine (GS) and chondroitin (CS), integrate the vascular extracellular matrix and may influence vascular endothelial cell growth. To assess the effects of these substances on blood vessel formation, we used the chick yolk sac membrane (YSM) model and fractal geometry quantification, which provided an objective in vivo method for testing potential agents that promote vasculogenesis and angiogenesis. An image processing method was developed to evaluate YSM capillary vessels after they were implanted in a methylcellulose disk of GS or CS at a concentration between 0.001-0.1mg/disk (performed on 2-day old embryos). This method resulted in a binary image of the microvascular network (white vessels on a black background). Fractal box-counting (DBC) and information (DINF) dimensions were used to quantify the activity of GS and CS in vasculogenesis and angiogenesis. YSM treated with GS (0.001-0.1mg) and CS (0.03-0.1mg) showed an increase in fractal dimensions that corresponded to vitelline vessel growth compared to the control group (vehicle), with GS displaying higher fractal dimension values. PMID:26873109

  17. Fractal analysis of extra-embryonic vessels of chick embryos under the effect of glucosamine and chondroitin sulfates.

    PubMed

    de Souza Lins Borba, Fernanda Katharine; Felix, Giovanni Loos Queiroz; Costa, Edbhergue Ventura Lola; Silva, Lisie; Dias, Paulo Fernando; de Albuquerque Nogueira, Romildo

    2016-05-01

    Like heparan sulfate proteoglycans, some monosaccharides and glycosaminoglycans, such as sulfated glucosamine (GS) and chondroitin (CS), integrate the vascular extracellular matrix and may influence vascular endothelial cell growth. To assess the effects of these substances on blood vessel formation, we used the chick yolk sac membrane (YSM) model and fractal geometry quantification, which provided an objective in vivo method for testing potential agents that promote vasculogenesis and angiogenesis. An image processing method was developed to evaluate YSM capillary vessels after they were implanted in a methylcellulose disk of GS or CS at a concentration between 0.001-0.1mg/disk (performed on 2-day old embryos). This method resulted in a binary image of the microvascular network (white vessels on a black background). Fractal box-counting (DBC) and information (DINF) dimensions were used to quantify the activity of GS and CS in vasculogenesis and angiogenesis. YSM treated with GS (0.001-0.1mg) and CS (0.03-0.1mg) showed an increase in fractal dimensions that corresponded to vitelline vessel growth compared to the control group (vehicle), with GS displaying higher fractal dimension values.

  18. A 'chemotactic dipole' mechanism for large-scale vortex motion during primitive streak formation in the chick embryo.

    PubMed

    Sandersius, S A; Chuai, M; Weijer, C J; Newman, T J

    2011-08-01

    Primitive streak formation in the chick embryo involves significant coordinated cell movement lateral to the streak, in addition to the posterior-anterior movement of cells in the streak proper. Cells lateral to the streak are observed to undergo 'polonaise movements', i.e. two large counter-rotating vortices, reminiscent of eddies in a fluid. In this paper, we propose a mechanism for these movement patterns which relies on chemotactic signals emitted by a dipolar configuration of cells in the posterior region of the epiblast. The 'chemotactic dipole' consists of adjacent regions of cells emitting chemo-attractants and chemo-repellents. We motivate this idea using a mathematical analogy between chemotaxis and electrostatics, and test this idea using large-scale computer simulations. We implement active cell response to both neighboring mechanical interactions and chemotactic gradients using the Subcellular Element Model. Simulations show the emergence of large-scale vortices of cell movement. The length and time scales of vortex formation are in reasonable agreement with experimental data. We also provide quantitative estimates for the robustness of the chemotaxis dipole mechanism, which indicate that the mechanism has an error tolerance of about 10% to variation in chemotactic parameters, assuming that only 1% of the cell population is involved in emitting signals. This tolerance increases for larger populations of cells emitting signals.

  19. Mitochondrial DNA polymerase, deoxyribonuclease and ribonuclease H activities from brain of chick embryo

    PubMed Central

    Soriano, L.; Smith, J.; Croisille, Y.; Dastugue, B.

    1974-01-01

    R-DNA polymerase, D-DNA polymerase, DNase and RNase H activities in mitochondria from chick embryonic brain were studied by ion-exchange chromatography. Two main fractions were separated according to their chromatographic behaviour: a fraction M Ib which is eluted with the washing buffer from two successive DEAE-cellulose columns and a fraction M IV which is eluted at 400 mM KC1 from a phosphocellulose column. Although the two fractions contain both the DNA polymerase and the degrading activities, all the specific activities are higher in fraction M IV than in fraction M Ib. Heat inactivation experiments have shown that R-DNA polymerase is inactivated in both fractions, whereas RNase H and DNase are not affected. Thus, degrading activities and R-DNA polymerase activity seem to be catalyzed by different molecular entities. However the fact that in most cases these activities co-chromatograph suggests that the corresponding molecules form rather stable complexes. PMID:4476911

  20. Enhanced growth and plaquing of rabies virus in static chick embryo cell culture.

    PubMed

    Sekine, N; Yoshino, K

    1976-08-01

    The 7-day egg passage line of HEP Flury strain of rabies virus was inoculated to primary chick embyro (CE) cells prepared in different ways to compared efficiencies of viral growth and plaquing. Special care to minimize cellular damage due to trypsin at the step of monodispersion and sowing a comparatively large number of cells for monolayer preparation were required for rabies plaquing, whereas such cares were not necessary for plaquing of vesicular stomatitis virus. Plaque number and size were increased by incorporation of a high concentration of thymidine into cell growth medium. Various other means to produce a static state of CE cells were tested, and a maximal plaquing efficiency was obtained when dishes receiving a massive number of dispersed cells in MEM plus 1% calf serum were incubated at 37 C for 1 day without any buffering for monolayer preparation and postinfection incubation was done at 32 C in a CO2-incubator. Bottle cultures of CE cells prepared in a similar manner, when infected with HEP Flury virus, yielded a markedly higher titer of virus that CE cells prepared by our previous standard method. PMID:185442

  1. The spatial and temporal pattern of beta NGF receptor expression in the developing chick embryo.

    PubMed Central

    Raivich, G; Zimmermann, A; Sutter, A

    1985-01-01

    To gain insight into the developmental program of nerve growth factor (NGF) receptor expression, the binding of [125I] beta NGF to frozen chick sections was investigated autorradiographically between embryonic day 3 (E3) and post-hatching day 3. Strong NGF receptor expression was observed as early as E4, throughout embryonic development and in the post-hatching period at the classical NGF target sites: the paravertebral sensory and sympathetic ganglia, the paraaortal sympathetic ganglia as well as the cranial sensory ganglia with neurons of neural crest origin and their respective nerves. Only weak [125I] beta NGF binding was observed during a restricted time span in the parasympathetic ciliary ganglion. Clear differences were observed in the intensity and in the developmental time course of [125I] beta NGF binding to the dorsomedial and ventrolateral aspects of the dorsal root ganglia. NGF receptors were also found to be expressed on central axons of the dorsal root entry zone and the dorsal tract in the spinal cord. A transient expression of specific NGF binding sites of the same high affinity as measured at the classical NGF targets, was detected in the lateral motor column and in muscle at the time of motoneuron synapse formation and elimination. Images Fig. 1.,Fig. 2., Fig. 3 Fig. 4.,Fig. 5., Fig. 6. Fig. 7., Fig. 8. PMID:2988932

  2. Dorsoventral compartmentalization of mesoderm in heart-forming area of chick embryo.

    PubMed

    Kärner, M; Krinka, D; Padari, K; Kärner, J; Raid, R

    2000-06-01

    In early chick development (stages 5-8) the seemingly homogeneous mesoderm in the heart-forming area splits to somatic and splanchnic cardiogenic layers. Little is known about dorsoventral compartmentalization before splitting. Electron microscopic analysis shows the early dorsoventral polarization of precardiomyocytes. The dorsal compartment has epithelial and the ventral compartment mesenchymal features with numerous protrusions. At stage 5+-6 staining for wheat germ agglutinine (WGA) transiently demarcates the ventral part of mesoderm. The glycosomes (beta-glycogen) show a dorsoventral gradient in the mesoderm of the cardiogenic field during the initial step of the compaction. The differential expression of glycosomes depends on the activity of glycogen synthase kinase 3-beta, a component of the wnt-signaling pathway, and might in this spatiotemporal developmental window be involved in the commitment of presumptive cardiogenic and somatic cells. To verify this hypothesis simulation experiments with LiCl in vitro were carried out. The normal splitting of the mesoderm and the development of heart primordia were disturbed. Blocking the receptors of WGA by WGA in vitro at stage 5-5+ perturbs the migration of mesoderm to anterio-medial direction. It appears that early specification of dorsal and ventral compartments of the mesoderm in the heart-forming area correlates with the gradient of glycosomes. Our results suggest that the target of LiCl action (glycogen synthase kinase 3-beta) might be involved in the specification of heart primordia and that WGA receptors mediate the migration of mesoderm to the anteriomedial direction.

  3. Multielectrode array recordings reveal physiological diversity of intrinsically photosensitive retinal ganglion cells in the chick embryo.

    PubMed

    Neumann, Tanja; Ziegler, Christiane; Blau, Axel

    2008-05-01

    Intrinsically photosensitive retinal ganglion cells (ipRGCs) play important roles in non-image forming photoreception and participate in the regulation of the circadian rhythm and the pupillary light reflex. The aim of the present work was to characterize the light response of ipRGCs at two developmental stages of the embryonic chick. The electrophysiological study was based on comparative multielectrode array recordings from acute retinal slices. To ensure that light was the only source of excitation, intercellular activity modulation by gap junctions and chemical synapses was inhibited by carbenoxolone and bafilomycin A1, respectively. Action potentials evoked by blue light were detected as early as day 13 of embryonic development, which is notably earlier than the completion of the maturation process of functional rods and cones. Three different response types were distinguished by their response latency and sensitivity to different illumination intensities. At this point it is not clear whether these types just represent different maturation stages or have different morphologies and functions with respect to the non-image forming visual system and circadian entrainment.

  4. Electroporation of the hindbrain to trace axonal trajectories and synaptic targets in the chick embryo.

    PubMed

    Kohl, Ayelet; Hadas, Yoav; Klar, Avihu; Sela-Donenfeld, Dalit

    2013-05-29

    Electroporation of the chick embryonic neural tube has many advantages such as being quick and efficient for the expression of foreign genes into neuronal cells. In this manuscript we provide a method that demonstrates uniquely how to electroporate DNA into the avian hindbrain at E2.75 in order to specifically label a subset of neuronal progenitors, and how to follow their axonal projections and synaptic targets at much advanced stages of development, up to E14.5. We have utilized novel genetic tools including specific enhancer elements, Cre/Lox - based plasmids and the PiggyBac-mediated DNA transposition system to drive GFP expression in a subtype of hindbrain cells (the dorsal most subgroup of interneurons, dA1). Axonal trajectories and targets of dA1 axons are followed at early and late embryonic stages at various brainstem regions. This strategy contributes advanced techniques for targeting cells of interest in the embryonic hindbrain and for tracing circuit formation at multiple stages of development.

  5. Comparison of embryo physiological parameters during incubation, chick quality, and growth performance of three lines of broiler breeders differing in genetic composition and growth rate.

    PubMed

    Tona, K; Onagbesan, O M; Jego, Y; Kamers, B; Decuypere, E; Bruggeman, V

    2004-03-01

    In broiler breeder management, stringent feed restriction is practiced to reduce body size in order to improve egg production and meet broiler production demand, but this practice has raised welfare issues. The potential for the dwarfing (dw) gene to reduce feed intake and body size of breeders under ad libitum feeding or less stringent restriction while maintaining improved egg production has been reported. In this study, we compared embryo physiology, quality of chicks, and performance of broilers from eggs of dwarf breeders with those from a standard broiler breeder. Hatching eggs from 3 commercial lines of broiler breeders were compared for incubation parameters, 1-d-old chick weight, chick quality, and broiler growth to 41 d of age. The lines included a standard heavy (S) line, an experimental (E) line, and a label-type (L) line. The E and L line breeders carry the sex-linked dw gene and are being used to assess the potential for dw to reduce feed intake or lower feed restriction and improve reproductive performance in heavy female broiler parent stock. Two separate experiments were conducted. All female parent stocks were mated to Cornish males, and fertile eggs were collected. In the first experiment, eggs were incubated for 21 d under standard conditions to determine, during final stages of incubation, corticosterone and thyroid hormone levels (triiodothyronine, T3; thyroxine, T4) in embryos and hatchlings, CO2 partial pressure (pCO2), and O2 partial pressure (pO2) in air cells, heat production by eggs and 1-d-old weights. In the second experiment, eggs were incubated for 21 d to compare chick quality, chick weights at 1 d of age, and broiler growth to 7 and 41 d. Average egg weights were higher for the S and L lines than the E line, but weight loss during incubation was lowest for the E line. Plasma T3 and T3/T4 ratio was similar between lines at IP, but corticosterone was higher in the S line. At hatch, T3/T4 ratio was higher in the S line compared with

  6. Effect of phorbol and Bryostatin I on chondrogenic expression of chick limb bud, in vitro

    SciTech Connect

    Garrison, J.C.; Pettit, G.R.; Uyeki, E.M.

    1987-10-26

    The present paper describes the effects of PMA (phorbol 12-myristate 13 acetate) on in vitro chondrogenesis in non-passaged, embryonic limb bud cells, relative to the effects of Bryostatin I. This compound also activates C kinase and binds competitively to the phorbol ester receptor, yet does not affect cell differentiation. Levels of PMA as low as 10/sup -7/ M markedly reduced cartilage formation in 4-day cultures, as indicated by nodule count and Alcian blue staining for chondroitin sulfate. Coadministration of Bryostatin I at equimolar concentration prevented the PMA inhibitory effect on chondrocytic expression. This confirms other findings that phorbol activation of C kinase cannot exclusively account for the activity of phorbol on cell expression. Altering the time of PMA exposure demonstrated that PMA inhibited chondrocyte phenotypic expression, rather than cell commitment: early exposure to PMA had little inhibitor effect on the staining index, whereas, exposure from 49-96 h and 0-96 h had moderate and strong inhibitory effects, respectively, on cartilage synthesis. Further research on the phorbol/Bryostatin I interaction should add to their knowledge of the control processes involved in tumor promotion and cell differentiation. 21 references, 3 figures.

  7. Induction of four proteins in chick embryo cells by sodium arsenite.

    PubMed

    Johnston, D; Oppermann, H; Jackson, J; Levinson, W

    1980-07-25

    Four proteins of Mr = 89,000, 73,000, 35,000, and 27,000 are strongly induced in chick fibroblasts by sodium arsenite. Induction of these proteins is discoordinate as a function of arsenite concentration. Kinetically, all species appear 1 h after exposure to 50 microM arsenite, after 24 and 48 h of exposure, the 27,000 protein is still synthesized extensively, whereas normal cell proteins and the three other induced proteins are greatly reduced. The four proteins are unrelated by tryptic peptide-mapping procedures. Multiple subspecies of p89, p73, and p27 were observed in two-dimensional gels. The subspecies of p73 appear to be related as determined by partial proteolytic maps as are those of p27. Two-dimensional gel analysis of in vitro translation products from rabbit reticulocyte lysates primed with mRNA from uninduced and induced cells reveals that the amount of translatable mRNA specific for these proteins is increase by induction. This increase is attributable to new mRNA synthesis since actinomycin D prevent induction and new bands of RNA (Mr = 0.9 X 10(6) and 1.3 X 10(6)) appear in methyl mercury gels of oligo(dT) selected RNA from induced cells. These bands are assigned to p73 and p89 based on translation of electroeluted RNA from a similar preparative gel. A comparison is made between induction of these proteins and the heat shock response in Drosophilla melanogaster. PMID:6893047

  8. A descriptive study to provide evidence of the teratogenic and cellular effects of sibutramine and ephedrine on cardiac- and liver-tissue of chick embryos.

    PubMed

    Oberholzer, Hester Magdalena; Van Der Schoor, Ciska; Taute, Helena; Bester, Megan Jean

    2015-08-01

    Exposure to drugs during pregnancy is a major concern, as some teratogenic compounds can influence normal foetal development. Although the use of drugs during pregnancy should generally be avoided, exposure of the developing foetus to teratogens may occur unknowingly since these compounds may be hidden in products that are being marketed as "all natural." The aim of the current study was to investigate the possible teratogenic and cellular effects of sibutramine-a serotonin-norepinephrine reuptake inhibitor used in the treatment of obesity-on the heart and liver tissue of chick embryos. Ephedrine was used as a positive control. The chick embryo model was chosen because it has been used in studying developmental and experimental biology and teratology with great success. The embryos were exposed to three different concentrations of sibutramine and ephedrine respectively. The results obtained revealed that both compounds exhibited embryotoxicity when compared to the control groups. Liver and heart tissue of the exposed embryos was severely affected by these compounds in a dose-related manner. Morphology similar to that of muscle dystrophy was observed in the heart, where the muscle tissue was infiltrated by adipose and connective tissue. Severe liver steatosis was also noted. A more in-depth investigation into the molecular pathways involved might provide more information on the exact mechanism of toxicity of these products influencing embryonic development.

  9. Focal adhesion kinase as a mechanotransducer during rapid brain growth of the chick embryo.

    PubMed

    Desmond, Mary E; Knepper, Janice E; DiBenedetto, Angela J; Malaugh, Elizabeth; Callejo, Sagrario; Carretero, Raquel; Alonso, Maria-Isabel; Gato, Angel

    2014-01-01

    Expansion of the hollow fluid-filled embryonic brain occurs by an increase in intraluminal pressure created by accumulation of cerebrospinal fluid (CSF). Experiments have shown a direct correlation between cavity pressure and cell proliferation within the neuroepithelium. These findings lead us to ask how mechanistically this might come about. Are there perhaps molecules on the luminal surface of the embryonic neuroepithelium, such as focal adhesion kinases (FAKs) known to respond to tension in other epithelial cells? Immunodetection using antibodies to total FAK and p-FAK was performed with subsequent confocal analysis of the pattern of their activation under normal intraluminal pressure and induced chronic pressure. Western analysis was also done to look at the amount of FAK expression, as well as its activation under these same conditions. Using immunolocalization, we have shown that FAK is present and activated on both apical and basolateral surfaces and within the cytoplasm of the neuroepithelial cells. This pattern changed profoundly when the neuroepithelium was under pressure. By Western blot, we have shown that FAK was upregulated and activated in the neuroepithelium of the embryos just after the neural tube becomes a closed pressurized system, with phosphorylation detected on the luminal instead of the basal surface, along with an increase in cell proliferation. Chronic hyper-pressure does not induce an increase in phosphorylation of FAK. In conclusion, here we show that neuroepithelial cells respond to intraluminal pressure via FAK phosphorylation on the luminal surface. PMID:24860993

  10. Control of the segmentation process by graded MAPK/ERK activation in the chick embryo.

    PubMed

    Delfini, Marie-Claire; Dubrulle, Julien; Malapert, Pascale; Chal, Jérome; Pourquié, Olivier

    2005-08-01

    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 graded activation of the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) pathway along the PSM in the chicken embryo. Using in ovo electroporation of PSM cells, we demonstrate that constitutive activation of ERK signaling in the PSM blocks segmentation by preventing maturation of PSM cells, thus phenocopying the overexpression of FGF8. Conversely, inhibition of ERK phosphorylation mimics a loss of function of FGF signaling in the PSM. Interestingly, video microscopy analysis of cell movements shows that ERK regulates the motility of PSM cells, suggesting that the decrease of cell movements along the PSM enables mesenchymal PSM cells to undergo proper segmentation. Together, our data demonstrate that ERK is the effector of the gradient of FGF in the PSM that controls the segmentation process.

  11. Binding characteristics of brain-derived neurotrophic factor to its receptors on neurons from the chick embryo

    SciTech Connect

    Rodriguez-Tebar, A.; Barde, Y.A.

    1988-09-01

    Brain-derived neurotrophic factor (BDNF), a protein known to support the survival of embryonic sensory neurons and retinal ganglion cells, was derivatized with 125I-Bolton-Hunter reagent and obtained in a biologically active, radioactive form (125I-BDNF). Using dorsal root ganglion neurons from chick embryos at 9 d of development, the basic physicochemical parameters of the binding of 125I-BDNF with its receptors were established. Two different classes of receptors were found, with dissociation constants of 1.7 x 10(-11) M (high-affinity receptors) and 1.3 x 10(-9) M (low-affinity receptors). Unlabeled BDNF competed with 125I-BDNF for binding to the high-affinity receptors with an inhibition constant essentially identical to the dissociation constant of the labeled protein: 1.2 x 10(-11) M. The association and dissociation rates from both types of receptors were also determined, and the dissociation constants calculated from these kinetic experiments were found to correspond to the results obtained from steady-state binding. The number of high-affinity receptors (a few hundred per cell soma) was 15 times lower than that of low-affinity receptors. No high-affinity receptors were found on sympathetic neurons, known not to respond to BDNF, although specific binding of 125I-BDNF to these cells was detected at a high concentration of the radioligand. These results are discussed and compared with those obtained with nerve growth factor on the same neuronal populations.

  12. Calbindin-immunoreactive sensory neurons in dissociated dorsal root ganglion cell cultures of chick embryo: role of culture conditions.

    PubMed

    Barakat, I; Droz, B

    1989-12-01

    Immunoreactivity to calbindin D-28k, a vitamin D-dependent calcium-binding protein, is expressed by neuronal subpopulations of dorsal root ganglia (DRG) in the chick embryo. To determine whether the expression of this phenotypic characteristic is maintained in vitro and controlled by environmental factors, dissociated DRG cell cultures were performed under various conditions. Subpopulations of DRG cells cultured at embryonic day 10 displayed calbindin-immunoreactive cell bodies and neurites in both neuron-enriched or mixed DRG cell cultures. The number of calbindin-immunoreactive ganglion cells increased up to 7-10 days of culture independently of the changes occurring in the whole neuronal population. The presence of non-neuronal cells, which promotes the maturation of the sensory neurons, tended to reduce the percentage of calbindin-immunoreactive cell bodies. Addition of horse serum enhanced both the number of calbindin-positive neurons and the intensity of the immunostaining, but does not prevent the decline of the subpopulation of calbindin-immunoreactive neurons during the second week of culture; on the contrary, the addition of muscular extract to cultures at 10 days maintained the number of calbindin-expressing neurons. While calbindin-immunoreactive cell bodies grown in culture were small- or medium-sized, no correlation was found between cell size and immunostaining density. At the ultrastructural level, the calbindin immunoreaction was distributed throughout the neuroplasm. These results indicate that the expression of calbindin by sensory neurons grown in vitro may be modulated by horse serum-contained factors or interaction with non-neuronal cells. As distinct from horse serum, muscular extract is able to maintain the expression of calbindin by a subpopulation of DRG cells.

  13. Chloride-sensitive MEQ fluorescence in chick embryo motoneurons following manipulations of chloride and during spontaneous network activity.

    PubMed

    Chub, Nikolai; Mentis, George Z; O'donovan, Michael J

    2006-01-01

    Intracellular Cl(-) ([Cl(-)](in)) homeostasis is thought to be an important regulator of spontaneous activity in the spinal cord of the chick embryo. We investigated this idea by visualizing the variations of [Cl(-)](in) in motoneurons retrogradely labeled with the Cl-sensitive dye 6-methoxy-N-ethylquinolinium iodide (MEQ) applied to cut muscle nerves in the isolated E10-E12 spinal cord. This labeling procedure obviated the need for synthesizing the reduced, cell-permeable dihydro-MEQ (DiH-MEQ). The specificity of motoneuron labeling was confirmed using retrograde co-labeling with Texas Red Dextran and immunocytochemistry for choline acetyltransferase (ChAT). In MEQ-labeled motoneurons, the GABA(A) receptor agonist isoguvacine (100 muM) increased somatic and dendritic fluorescence by 7.4 and 16.7%, respectively. The time course of this fluorescence change mirrored that of the depolarization recorded from the axons of the labeled motoneurons. Blockade of the inward Na(+)/K(-)/2Cl(-) co-transporter (NKCC1) with bumetanide (20 microM) or with a low-Na(+) bath solution (12 mM), increased MEQ fluorescence by 5.3 and 11.4%, respectively, consistent with a decrease of [Cl(-)](in). After spontaneous episodes of activity, MEQ fluorescence increased and then declined to the pre-episode level during the interepisode interval. The largest fluorescence changes occurred over motoneuron dendrites (19.7%) with significantly smaller changes (5.2%) over somata. Collectively, these results show that retrogradely loaded MEQ can be used to detect [Cl(-)](in) in motoneurons, that the bumetanide-sensitive NKCC1 co-transporter is at least partially responsible for the elevated [Cl(-)](in) of developing motoneurons, and that dendritic [Cl(-)](in) decreases during spontaneous episodes and recovers during the inter-episode interval, presumably due to the action of NKCC1. PMID:16192339

  14. Studies on the psittacosis-lymphogranuloma group. 1. The pattern of multiplication of meningopneumonitis virus in the allantois of the chick embryo.

    PubMed

    SIGEL, M M; GIRARDI, A J; ALLEN, E G

    1951-11-01

    Because of the peculiar properties of the psittacosis-lymphogranuloma group of viruses, the pattern of multiplication in the allantois of the chick embryo of one of their number, meningopneumonitis virus, was studied. This was done by determination of the changes in its infectivity for mice and chick embryos. Titration of infectivity in embryos proved to be a more sensitive procedure than titration in mice; the latter procedure however, had the advantage of greater simplicity and gave more clear-cut results. The mouse titration method was used in most of the experiments. Following inoculation of virus into the allantois, there was a slow decrease in infectivity in the allantoic fluids followed by an increase due to appearance of new virus between 24 and 48 hours. The slope of declining infectivity in the allantoic fluids in ovo was similar if not identical with the slope of decreasing infectivity in allantoic fluids in vitro caused by thermal degradation of virus. Multiplication of the virus in allantoic membranes was characterized by the following pattern: (a) Increase in infectivity in the first few hours (exact duration of increase depended on concentration of virus in inoculum) due to adsorption of virus. (b) Decrease in infectivity up to about 20 to 24 hours. (c) Increase in infectivity due to appearance of the new generation of virus. The growth curve of meningopneumonitis is analyzed and the pattern of growth is discussed in the light of the present concepts of viral multiplication.

  15. Toxicity of scorpion venom in chick embryo and mealworm assay depending on the use of the soluble fraction versus the whole venom.

    PubMed

    van der Valk, Tom; van der Meijden, Arie

    2014-09-01

    The LD50 is an important metric for venom studies and antivenom development. It has been shown that several variables in the protocol influence the LD50 value obtained, such as venom source, extraction and treatment and administration route. These inconsistencies reduce the utility of the results of these test for comparative studies. In scorpion venom LD50 assays, often only the soluble fraction of the venom is used, whereas other studies use the whole venom. We here tested the toxicity of the soluble fraction in isolation, and of the whole venom in two different systems: chick embryos and mealworms Tenebrio molitor. Ten microliters of venom solutions from Hadrurus arizonensis, Leiurus quinquestriatus, Androctonus australis, Grosphus grandidieri and Heterometrus laoticus were applied to five day old chicken embryos at stage 25-27. Our results showed no significant differences between the LD50 based on the whole venom versus that of only the soluble fraction and in the chicken embryo assay in four of the five scorpion species tested. H. laoticus however, showed a significantly lower LD50 value for the whole venom than the soluble fraction. In assays on mealworms however, this pattern was not seen. Nonetheless, caution may be warranted when using LD50 values obtained from only the soluble fraction. The LD50 values of the five species in this study, based on the chicken embryo assay, showed good correlation with values from the literature based on mouse studies. This suggests that the chick embryo assay may be an economic alternative to rodent assays for scorpion LD50 studies. PMID:24951875

  16. The relationship between gene expression of cationic and neutral amino acid transporters in the small intestine of chick embryos and chick breed, development, sex, and egg amino acid concentration.

    PubMed

    Zeng, P L; Li, X G; Wang, X Q; Zhang, D X; Shu, G; Luo, Q B

    2011-11-01

    This study was conducted to investigate the gene expression of cationic and neutral amino acid (AA) transporters in the small intestine of chick embryos with different genetic backgrounds [Wenshi Yellow-Feathered chick (WYFC) and White Recessive Rock chick (WRRC)]. The study also investigated the correlation between the abundance of AA transporter mRNA and the AA content of fertilized eggs. Intestinal samples were collected on embryonic d 9, 12, 14, 17, and 19 and the day of hatch. The results showed that, before incubation, the AA content of WRRC eggs was lower (P < 0.05) than the AA content of WYFC eggs. In WYFC, the mRNA abundance of CAT-1 [solute carrier (SLC) family 7 member 1], CAT-4 (SLC family 7 member 4), rBAT (SLC family 3 member 1), y(+)LAT-1 (SLC family 7 member 7), y(+)LAT-2 (SLC family 7 member 6), LAT-4 (SLC family 43 member 2), and SNAT-2 (SLC family 38 member 2), as detected by real-time reverse transcriptase PCR, was greater (P < 0.05) than the mRNA abundance detected in the WRRC samples. The mRNA abundance of all measured AA transporters was affected (P < 0.05) by embryonic age. Sex had the largest effect (P < 0.05) on the mRNA expression of CAT-1, CAT-4, y(+)LAT-2, and LAT-4 in WYFC and on CAT-4 and B(0)AT-1 (SLC family 6 member 19) mRNA expression in WRRC. In WYFC, only CAT-1 mRNA expression was negatively correlated (r = -0.68 to -0.84, P < 0.05) with all AA content. However, few correlations were detected between AA content and the mRNA expression of multiple transporters in WRRC. These findings provide a comprehensive profile of the temporal and spatial mRNA expression of AA transporters in the small intestine of chick embryos. Few correlations were detected between the AA content of the eggs and mRNA expression of specific AA transporters in the small intestine.

  17. Development of receptors for insulin and insulin-like growth factor-I in head and brain of chick embryos: Autoradiographic localization

    SciTech Connect

    Bassas, L.; Girbau, M.; Lesniak, M.A.; Roth, J.; de Pablo, F. )

    1989-11-01

    In whole brain of chick embryos insulin receptors are highest at the end of embryonic development, while insulin-like growth factor-I (IGF-I) receptors dominate in the early stages. These studies provided evidence for developmental regulation of both types of receptors, but they did not provide information on possible differences between brain regions at each developmental stage or within one region at different embryonic ages. We have now localized the specific binding of (125I)insulin and (125I)IGF-I in sections of head and brain using autoradiography and computer-assisted densitometric analysis. Embryos have been studied from the latter part of organogenesis (days 6 and 12) through late development (day 18, i.e. 3 days before hatching), and the binding patterns have been compared with those in the adult brain. At all ages the binding of both ligands was to discrete anatomical regions. Interestingly, while in late embryos and adult brain the patterns of (125I)insulin and (125I) IGF-I binding were quite distinct, in young embryos both ligands showed very similar localization of binding. In young embryos the retina and lateral wall of the growing encephalic vesicles had the highest binding of both (125I)insulin and (125I)IGF-I. In older embryos, as in the adult brain, insulin binding was high in the paleostriatum augmentatum and molecular layer of the cerebellum, while IGF-I binding was prominent in the hippocampus and neostriatum. The mapping of receptors in a vertebrate embryo model from early prenatal development until adulthood predicts great overlap in any possible function of insulin and IGF-I in brain development, while it anticipates differential localized actions of the peptides in the mature brain.

  18. Quantitative analysis of tissue deformation dynamics reveals three characteristic growth modes and globally aligned anisotropic tissue deformation during chick limb development

    PubMed Central

    Morishita, Yoshihiro; Kuroiwa, Atsushi; Suzuki, Takayuki

    2015-01-01

    Tissue-level characterization of deformation dynamics is crucial for understanding organ morphogenetic mechanisms, especially the interhierarchical links among molecular activities, cellular behaviors and tissue/organ morphogenetic processes. Limb development is a well-studied topic in vertebrate organogenesis. Nevertheless, there is still little understanding of tissue-level deformation relative to molecular and cellular dynamics. This is mainly because live recording of detailed cell behaviors in whole tissues is technically difficult. To overcome this limitation, by applying a recently developed Bayesian approach, we here constructed tissue deformation maps for chick limb development with high precision, based on snapshot lineage tracing using dye injection. The precision of the constructed maps was validated with a clear statistical criterion. From the geometrical analysis of the map, we identified three characteristic tissue growth modes in the limb and showed that they are consistent with local growth factor activity and cell cycle length. In particular, we report that SHH signaling activity changes dynamically with developmental stage and strongly correlates with the dynamic shift in the tissue growth mode. We also found anisotropic tissue deformation along the proximal-distal axis. Morphogenetic simulation and experimental studies suggested that this directional tissue elongation, and not local growth, has the greatest impact on limb shaping. This result was supported by the novel finding that anisotropic tissue elongation along the proximal-distal axis occurs independently of cell proliferation. Our study marks a pivotal point for multi-scale system understanding in vertebrate development. PMID:25858459

  19. High titer growth of human and avian influenza viruses in an immortalized chick embryo cell line without the need for exogenous proteases.

    PubMed

    Smith, Kristen A; Colvin, Christopher J; Weber, Patty S D; Spatz, Stephen J; Coussens, Paul M

    2008-07-01

    The current method of growing influenza virus for vaccine production is through the use of embryonated chicken eggs. This manufacturing system yields a low concentration of virus per egg, requires significant downstream production for purification, and demands a considerable amount of time for production. We have demonstrated an immortalized chick embryo cell line, termed PBS-1, is capable of growing unmodified recent isolates of human and avian influenza A and B viruses to extremely high titers. In many cases, PBS-1 cells out perform primary chick embryo kidney (CEK) cells, Madin-Darby Canine Kidney (MDCK) cells and African green monkey kidney cells (Vero) in growth of recent influenza isolates. PBS-1 cells are free of any exogenous agents, are non-tumorigenic, and are readily adaptable to a variety of culture conditions, including growth on microcarrier beads. Influenza viruses grown in PBS-1 cells are released into the culture fluid without the need for exogenous proteases, thus simplifying downstream processing. In addition to offering a significant improvement in vaccine production, PBS-1 cells should prove valuable in diagnostics and as a cell line of choice for influenza virus research.

  20. The metencephalic floor plate of chick embryos expresses two secretory glycoproteins homologous with the two glycoproteins secreted by the subcommissural organ.

    PubMed

    del Brío, M A; Riera, P; Muñoz, R I; Montecinos, H; Rodríguez, E M

    2000-06-01

    The nature and the function of the compounds secreted by the floor plate (FP) of the metencephalon are little known. The FP cells of the hindbrain react with antibodies (AFRU) against the glycoproteins secreted by the subcommissural organ (SCO). One of the these proteins, RF-Gly I, is a 540-kDa core glycosylated protein. The aims of the present investigation were to identify by immunoblot the AFRU-immunoreactive compound secreted by the FP of chick embryos, to establish temporal and regional patterns of this secretory activity, and to obtain information about the fate of these compounds. It was established that the SCO and FP of chick embryos secrete two AFRU-immunoreactive compounds of 540 and 230 kDa. The two compounds secreted by the FP have been designated as FP-Gly I and FP-Gly II. The expression of these proteins was circumscribed to the metencephalic FP, and occurred from HH 29 to HH 36. Within the FP cells, FP-Gly I and FP-Gly II were confined to the supranuclear and apical regions, which under the electron microscope displayed numerous cisternae of the rough endoplasmic reticulum and granules. Aggregates of AFRU-immunoreactive material appeared on the free surface of the FP. The possibility that FP-Gly I and FP-Gly II are released into the ventricle to reach distant targets is discussed.

  1. Great Lakes embryo mortality, edema, and deformities syndrome (GLEMEDS) in colonial fish-eating birds: similarity to chick-edema disease.

    PubMed

    Gilbertson, M; Kubiak, T; Ludwig, J; Fox, G

    1991-08-01

    Several species of colonial fish-eating birds nesting in the Great Lakes basin, including herring gulls, common terns and double-crested cormorants, have exhibited chronic impairment of reproduction. In addition to eggshell thinning caused by high levels of DDT and metabolites, the reproductive impairment is characterized by high embryonic and chick mortality, edema, growth retardation, and deformities, hence the name Great Lakes embryo mortality, edema, and deformities syndrome (GLEMEDS). The hypothesis has been advanced that GLEMEDS in colonial fish-eating birds resembles chick-edema disease of poultry and has been caused by exposure to chick-edema active compounds that have a common mode of action through the cytochrome P-448 system. Detailed evidence has been collected from the following three groups of studies on herring gulls in the lower Great Lakes during the early 1970s; Forster's terns in Green Bay, Wisconsin in 1983; and double-crested cormorants and Caspian terns in various locations in the upper Great Lakes from 1986 onwards. It has proved difficult to establish not only the onset of the disease in the various species at various locations but also the period in which chick-edema active compounds were released. Anecdotal evidence suggested that serious egg mortality in Lake Ontario herring gulls first occurred in 1966, through the signs of chick-edema disease were not looked for until 1974. Only indirect evidence is available on the date of the release of one of the presumed causal agents, 2,3,7,8-tetrachlorodibenzo-p-dioxin, but highest levels may have occurred in the early to mid 1960s. More reliable data show that the onset of the improvement of reproduction of Lake Ontario herring gulls coincided with the declines in organochlorine compounds and particularly 2,3,7,8-TCDD and PCB. Similarly, information on the onset of the disease and exposures in the Forster's tern and double-crested cormorants in Green Bay is uncertain but bird banders did not

  2. 3D Reconstruction of Chick Embryo Vascular Geometries Using Non-invasive High-Frequency Ultrasound for Computational Fluid Dynamics Studies.

    PubMed

    Tan, Germaine Xin Yi; Jamil, Muhammad; Tee, Nicole Gui Zhen; Zhong, Liang; Yap, Choon Hwai

    2015-11-01

    Recent animal studies have provided evidence that prenatal blood flow fluid mechanics may play a role in the pathogenesis of congenital cardiovascular malformations. To further these researches, it is important to have an imaging technique for small animal embryos with sufficient resolution to support computational fluid dynamics studies, and that is also non-invasive and non-destructive to allow for subject-specific, longitudinal studies. In the current study, we developed such a technique, based on ultrasound biomicroscopy scans on chick embryos. Our technique included a motion cancelation algorithm to negate embryonic body motion, a temporal averaging algorithm to differentiate blood spaces from tissue spaces, and 3D reconstruction of blood volumes in the embryo. The accuracy of the reconstructed models was validated with direct stereoscopic measurements. A computational fluid dynamics simulation was performed to model fluid flow in the generated construct of a Hamburger-Hamilton (HH) stage 27 embryo. Simulation results showed that there were divergent streamlines and a low shear region at the carotid duct, which may be linked to the carotid duct's eventual regression and disappearance by HH stage 34. We show that our technique has sufficient resolution to produce accurate geometries for computational fluid dynamics simulations to quantify embryonic cardiovascular fluid mechanics.

  3. Effects of male and female sex steroids on the development of normal and the transient Froriep's dorsal root ganglia of the chick embryo.

    PubMed

    Liu, Jiali; Chen, Dawei; Goldstein, Ronald S; Cui, Sheng

    2005-03-22

    Sex steroids can influence developmental processes and support the survival of neurons in the embryonic central nervous system. Recent studies have shown that estrogen receptors are also expressed in the peripheral nervous system, in the dorsal root ganglia (DRG) of chick embryos. However, no studies have examined the effects of sex steroids on development of embryonic DRG. In the present study, 0.2 microg, 1.0 microg, 5.0 microg 10 microg, 20 microg, 25 microg, and 40 microg doses of testosterone or estradiol were delivered to chick embryos at Hamburger and Hamilton stage 18 (E3). The actions of these doses of sex steroids on the development of the C5DRG (fifth cervical ganglion, a "normal" DRG) and C2DRG (a transient ganglion known as a "Froriep's DRG") were then evaluated by quantifying ganglionic volumes, cell number, proliferation, and apoptosis after 1 day of growth to stage 23. We found that both testosterone and estradiol promoted proliferation of cells in both normal DRG and the Froriep's ganglia. By contrast, estradiol significantly increased the number of apoptotic cells, while testosterone strongly inhibited apoptosis. These actions of sex steroids on DRG development were dose-dependent, and C5DRG and C2DRG showed different sensitivities to the applied sex steroids. In addition, the present results demonstrated that specific ER and AR inhibitors (tamoxifen and flutamide) did not influence the effects of 5 microg E2 and 5 microg T on C2 and C5DRG significantly. These results demonstrate that male and female sex steroids can modulate DRG development through an epigenetic mechanism, as had been shown for the central nervous system.

  4. The chronic infusion of nicotine into the developing chick embryo does not alter the density of (-)-[3H]nicotine-binding sites or vestibular function

    NASA Technical Reports Server (NTRS)

    Roll, R. L.; Jones, T. A.; Benowitz, N. L.; Morley, B. J.

    1993-01-01

    (-)-Nicotine (1.2 mg/day) or saline was infused into chick embryos (Gallus domesticus) for 10 days beginning 12 h beyond the eight day of incubation (E8 + 12 h). Twelve h beyond the eighteenth day of incubation (E18 + 12 h), the eggs were opened to access the embryos and subcutaneous skull electrodes placed. Short latency vestibular response thresholds and input/output functions were determined to assess neurophysiological consequences of chronic nicotine administration. Samples of serum and extraembryonic (amniotic and albumen) fluid were analyzed by gas chromatography-mass spectrometry to determine the levels of nicotine and its major metabolite, cotinine. The brains were removed and divided into diencephalon and mesencephalon and the density of (-)-[3H]nicotine binding sites in each brain area was measured. Nicotine and cotinine were found in the serum and extraembryonic fluid, but nicotinic receptors were not up-regulated in the brains of animals infused with nicotine in comparison to controls. Vestibular response thresholds also did not differ between nicotine-treated and control animals.

  5. SDOCT Doppler velocimetry for investigating the morphological influences on blood flow in the developing chick embryo heart

    NASA Astrophysics Data System (ADS)

    Davis, Anjul M.; Rothenberg, Florence G.; Law, Tzuo H.; Taber, Larry A.; Izatt, Joseph A.

    2007-02-01

    The onset of congenital heart disease (CHD) is believed to occur at very early stages of development. Investigations in the initiation and development of CHD has been hampered by the inability to image early stage heart structure and function, in vivo. Imaging small animals using optical coherence tomography (OCT) has filled a niche between the limited penetration depth of confocal microscopy and insufficient resolution from ultrasound. Previous demonstrations of chick heart imaging using OCT have entailed excision of, or arresting the heart to prevent motion artifacts. In this summary, we introduce SDOCT Doppler velocimetry as an enhancement of Doppler OCT for in vivo measurement of localized temporal blood flow dynamics. With this technique, dynamic velocity waveforms were measured in the outflow tract of the heart tube. These flow dynamics correlate to a finite element model of pulsatile flow and may lead to a further understanding of morphological influences on early heart development.

  6. Glutamine Synthetase is Expressed by Primary Sensory Neurons from Chick Embryos In Vitro but not In Vivo: Influence of Skeletal Muscle Extract.

    PubMed

    Barakat-Walter, I.; Droz, B.

    1990-01-01

    Glutamine synthetase (GS) catalyses the ATP-dependent formation of glutamine from glutamate and ammonia. To determine whether dorsal root ganglion (DRG) cells from chick embryos express the enzyme in vivo or in vitro, GS was detected by immunocytochemical reaction either in vibratome sections of DRG or in dissociated DRG cell cultures. The immunocytochemical detection of GS showed that in vivo the DRG taken from chick embryos at day 10 (E10), E14, E18 or from chickens after hatching were free of any GS-positive ganglion cells; in contrast, in neuron-enriched cultures of DRG cells grown in vitro at E10, virtually all the neuronal cells (98.6 +/- 1.0%) express GS at 3, 5 or 7 days of culture. In mixed DRG cell cultures, only 83.6+/-4.6% of the neurons displayed a GS-immunoreactivity. In both culture conditions, neither the presence of horse serum nor the age of the culture appeared to affect the percentage of neurons which displayed a GS-immunoreactivity. After [3H]glutamine uptake, radioautographs revealed that only 80% of the neurons were labelled in neuron-enriched DRG cell cultures while 96% of the neurons were radioactive in mixed DRG cell cultures. Furthermore the most heavily [3H]glutamine-labelled neurons were exclusively found in mixed DRG cell cultures. Combination of both immunocytochemical detection of GS and radioautography after [3H]glutamine uptake showed that strongly GS-immunostained neurons corresponded to poorly radioactive ones and vice versa. When skeletal muscle extract (ME) was added to DRG cell cultures, the number of GS-positive neurons was reduced to 77.5 +/- 2.5% in neuron-enriched cultures or to 43.6 +/- 3.8% in mixed DRG cell cultures; in both types of culture, the intensity of the neuronal immunostaining was depressed. Furthermore, combined action of ME and non-neuronal cells potentiates the enzyme repression exerted separately by ME or non-neuronal cells. Since GS-immunoreactivity is expressed in DRG cells grown in vitro, but not in

  7. Development of the arterial pattern in the upper limb of staged human embryos: normal development and anatomic variations

    PubMed Central

    RODRÍGUEZ-NIEDENFÜHR, M.; BURTON, G. J.; DEU, J.; SAÑUDO, J. R.

    2001-01-01

    A total of 112 human embryos (224 upper limbs) between stages 12 and 23 of development were examined. It was observed that formation of the arterial system in the upper limb takes place as a dual process. An initial capillary plexus appears from the dorsal aorta during stage 12 and develops at the same rate as the limb. At stage 13, the capillary plexus begins a maturation process involving the enlargement and differentiation of selected parts. This remodelling process starts in the aorta and continues in a proximal to distal sequence. By stage 15 the differentiation has reached the subclavian and axillary arteries, by stage 17 it has reached the brachial artery as far as the elbow, by stage 18 it has reached the forearm arteries except for the distal part of the radial, and finally by stage 21 the whole arterial pattern is present in its definitive morphology. This differentiation process parallels the development of the skeletal system chronologically. A number of arterial variations were observed, and classified as follows: superficial brachial (7.7%), accessory brachial (0.6%), brachioradial (14%), superficial brachioulnar (4.7%), superficial brachioulnoradial (0.7%), palmar pattern of the median (18.7%) and superficial brachiomedian (0.7%) arteries. They were observed in embryos belonging to stages 17–23 and were not related to a specific stage of development. Statistical comparison with the rates of variations reported in adults did not show significant differences. It is suggested that the variations arise through the persistence, enlargement and differentiation of parts of the initial network which would normally remain as capillaries or even regress. PMID:11693301

  8. Quantitation of methylxanthinic alkaloids and phenolic compounds in mate (Ilex paraguariensis) and their effects on blood vessel formation in chick embryos.

    PubMed

    Strassmann, Betina B; Vieira, Ana R; Pedrotti, Enio L; Morais, Hiliana N F; Dias, Paulo F; Maraschin, Marcelo

    2008-09-24

    Methylxanthinic alkaloids and phenolic compounds are related to the therapeutic properties of Ilex paraguariensis infusions. Considering the known vascular tropism of xanthines, an aqueous extract (mate) and caffeine were evaluated on blood vessel formation, in connection with the analysis of those secondary metabolites, which was performed in young and mature leaf samples collected in three cultivation systems located in the southern region in Brazil (Santa Catarina State). Samples of young and mature leaves from a monoculture cultivation system (MC) showed the highest content of phenolic compounds (149.68 microg/mL, young leaves; 135.50 microg/mL, mature leaves) and caffeine (young leaves, 148.07 microg/mL; mature leaves, 244.63 microg/mL) as compared to samples from agroforesty (AF) and shaded-native (NT) cultures. Theophylline was not detected in samples by reverse phase-high performance liquid chromatography, and mature leaves showed lower theobromine amounts (11.46 microg/mL). Treatments performed with mate aqueous extract and caffeine (1.03-4.12 microM/disk) in the yolk sac vascular membranes of 2-day-old chick embryos revealed pro-vasculo- and angiogenic properties as well as embryonic growth enhancement. These findings, uncoupled from any detectable embryotoxic effect, suggest a potential therapeutic and/or prophylactic use in cardiovascular disorders for caffeine and related constituents of mate plant extracts, an issue that waits further studies.

  9. Comparison of medetomidine, thiopental and ketamine/midazolam anesthesia in chick embryos for in ovo Magnetic Resonance Imaging free of motion artifacts.

    PubMed

    Waschkies, Conny; Nicholls, Flora; Buschmann, Johanna

    2015-10-23

    Non-invasive assessment of the perfusion capacity of tissue engineered constructs grown on the chorioallantoic membrane by MRI is often hampered by motion artifacts. Therefore, we examined the suitability of three anesthetic regimes for sufficient sedation of the chick embryo. Medetomidine at a dosage of 0.3 mg/kg, was compared to thiopental at 100 mg/kg and ketamine/midazolam at 50 mg/kg and 1 mg/kg, respectively. These soluble anesthetics were applied by dropping a total volume of 0.3 mL onto the surface of the CAM. Motion was videotaped through the window of the eggshell and scored semi-quantitatively. Medetomidine performed best in terms of reduced motion; onset of anesthesia occurred within 10 minutes and for the following 30 minutes, allowing proper in vivo MRI measurements. The other regimen were not sedating deep enough (ketamine/midazolam) and not long enough (thiopental). In sum, medetomidine allows proper sedation for MRI assessment of the perfusion capacity in a tissue engineered construct placed on the CAM.

  10. Comparison of medetomidine, thiopental and ketamine/midazolam anesthesia in chick embryos for in ovo Magnetic Resonance Imaging free of motion artifacts

    PubMed Central

    Waschkies, Conny; Nicholls, Flora; Buschmann, Johanna

    2015-01-01

    Non-invasive assessment of the perfusion capacity of tissue engineered constructs grown on the chorioallantoic membrane by MRI is often hampered by motion artifacts. Therefore, we examined the suitability of three anesthetic regimes for sufficient sedation of the chick embryo. Medetomidine at a dosage of 0.3 mg/kg, was compared to thiopental at 100 mg/kg and ketamine/midazolam at 50 mg/kg and 1 mg/kg, respectively. These soluble anesthetics were applied by dropping a total volume of 0.3 mL onto the surface of the CAM. Motion was videotaped through the window of the eggshell and scored semi-quantitatively. Medetomidine performed best in terms of reduced motion; onset of anesthesia occurred within 10 minutes and for the following 30 minutes, allowing proper in vivo MRI measurements. The other regimen were not sedating deep enough (ketamine/midazolam) and not long enough (thiopental). In sum, medetomidine allows proper sedation for MRI assessment of the perfusion capacity in a tissue engineered construct placed on the CAM. PMID:26493765

  11. Characterization of MARCKS (Myristoylated alanine-rich C kinase substrate) identified by a monoclonal antibody generated against chick embryo neural retina.

    PubMed

    Zolessi, F R; Hellman, U; Baz, A; Arruti, C

    1999-04-13

    To identify molecular markers of cell differentiation in developing nervous tissue, monoclonal antibodies against chick embryo neural retina were made. One of them, 3C3mAb, recognized a developmentally regulated antigen present in several organs of the CNS. Data from MALDI-TOF mass spectrometry and peptide sequencing of the immuno-affinity purified protein indicated identity of the antigen with MARCKS. The immunoreactive material was always found as a unique polypeptide (Mr 71 kDa) in SDS-PAGE, however isoelectrofocusing revealed the existence of several bands (pI ranging from 4.0 to 4.5). Interestingly some retinal cell types, as photoreceptors, exhibited an extremely significant decrease in the intensity of the immunoreactive material during the final phases of terminal differentiation while others, as some retinal neurons, maintained the immunoreactivity when fully differentiated. Taken together these results indicate that MARCKS, a protein susceptible of several posttranslational modifications as myristoylation and phosphorylation at variable extent, may act differently in neural retina cell types.

  12. Characterization of MARCKS (Myristoylated alanine-rich C kinase substrate) identified by a monoclonal antibody generated against chick embryo neural retina.

    PubMed

    Zolessi, F R; Hellman, U; Baz, A; Arruti, C

    1999-04-13

    To identify molecular markers of cell differentiation in developing nervous tissue, monoclonal antibodies against chick embryo neural retina were made. One of them, 3C3mAb, recognized a developmentally regulated antigen present in several organs of the CNS. Data from MALDI-TOF mass spectrometry and peptide sequencing of the immuno-affinity purified protein indicated identity of the antigen with MARCKS. The immunoreactive material was always found as a unique polypeptide (Mr 71 kDa) in SDS-PAGE, however isoelectrofocusing revealed the existence of several bands (pI ranging from 4.0 to 4.5). Interestingly some retinal cell types, as photoreceptors, exhibited an extremely significant decrease in the intensity of the immunoreactive material during the final phases of terminal differentiation while others, as some retinal neurons, maintained the immunoreactivity when fully differentiated. Taken together these results indicate that MARCKS, a protein susceptible of several posttranslational modifications as myristoylation and phosphorylation at variable extent, may act differently in neural retina cell types. PMID:10198238

  13. Immunoglobulin-containing cells in chick embryo urogenital tissues: a new site for early B lineage cells in endothermic vertebrates.

    PubMed

    Zettergren, L D; Cutlan, R T

    1992-07-01

    We have employed histological and immunofluorescent staining procedures in order to characterize the distribution of mu + B lineage cells in tissue sections prepared from developing chicken embryo urogenital tissues (UGTs) between 14 and 21 days of incubation. B lineage cells were observed in tissue sections prepared from developing UGTs, especially the mesonephros and its associated tissue, throughout the sample period. The highest densities of mu + B lineage cells were observed in tissue sections prepared from 18 day embryos. The mu + UGT cells were distributed singly and in clusters in subcapsular regions and within the peritubular interstitium of the mesonephros. These observations (1) are consistent with those which suggest nonbursal site(s) for origin of cells in B lineage, (2) may help account for the varying effects of embryonic caudectomy performed between the second and third days of incubation and surgical bursectomy performed close to hatching, (3) may help provide new insights on the effects of sex hormones on B cell development, and (4) suggest fundamental ontogenetic and phylogenetic similarities between developing vertebrate immune systems.

  14. Simulating Limb Formation in the U.S. EPA Virtual Embryo - Risk Assessment Project

    EPA Science Inventory

    The U.S. EPA’s Virtual Embryo project (v-Embryo™) is a computer model simulation of morphogenesis that integrates cell and molecular level data from mechanistic and in vitro assays with knowledge about normal development processes to assess in silico the effects of chemicals on d...

  15. Cases of limb-body wall complex: Early amnion rupture, vascular disruption, or abnormal splitting of the embryo?

    PubMed Central

    Crespo, Frank; Pinar, Halit; Kostadinov, Stefan

    2012-01-01

    We report two cases of limb-body wall complex (LBWC), also known as body stalk anomaly, a rare form of body wall defect incompatible with life. The first case was identified during a level II ultrasound examination performed at 7 wk gestational age. The delivery was by breech extraction at 39 wk and 4 days. The second case was delivered by spontaneous vaginal delivery at 35 wk and 5 days. Karyotype analysis was normal in both fetuses. The phenotype of LBWC is variable, but commonly identified features include: exencephaly, limb defects, and either facial clefts or thoraco-abdominoschisis. The exact etiology remains uncertain, as the disorder has been regarded as sporadic with low recurrence. Vascular disruption during early embryogenesis, early amnion rupture, abnormal splitting of the embryo, and failure of amnion fusion have been implicated in the pathogenesis of LBWC. A role for possible gene mutation and maternal use of alcohol, tobacco, or illicit drugs has also been suggested. Detailed ultrasonography along with biochemical screening may allow for early detection.

  16. Cases of limb-body wall complex: Early amnion rupture, vascular disruption, or abnormal splitting of the embryo?

    PubMed

    Crespo, Frank; Pinar, Halit; Kostadinov, Stefan

    2012-12-01

    We report two cases of limb-body wall complex (LBWC), also known as body stalk anomaly, a rare form of body wall defect incompatible with life. The first case was identified during a level II ultrasound examination performed at 7 wk gestational age. The delivery was by breech extraction at 39 wk and 4 days. The second case was delivered by spontaneous vaginal delivery at 35 wk and 5 days. Karyotype analysis was normal in both fetuses. The phenotype of LBWC is variable, but commonly identified features include: exencephaly, limb defects, and either facial clefts or thoraco-abdominoschisis. The exact etiology remains uncertain, as the disorder has been regarded as sporadic with low recurrence. Vascular disruption during early embryogenesis, early amnion rupture, abnormal splitting of the embryo, and failure of amnion fusion have been implicated in the pathogenesis of LBWC. A role for possible gene mutation and maternal use of alcohol, tobacco, or illicit drugs has also been suggested. Detailed ultrasonography along with biochemical screening may allow for early detection. PMID:27625829

  17. Cases of limb-body wall complex: Early amnion rupture, vascular disruption, or abnormal splitting of the embryo?

    PubMed

    Crespo, Frank; Pinar, Halit; Kostadinov, Stefan

    2012-12-01

    We report two cases of limb-body wall complex (LBWC), also known as body stalk anomaly, a rare form of body wall defect incompatible with life. The first case was identified during a level II ultrasound examination performed at 7 wk gestational age. The delivery was by breech extraction at 39 wk and 4 days. The second case was delivered by spontaneous vaginal delivery at 35 wk and 5 days. Karyotype analysis was normal in both fetuses. The phenotype of LBWC is variable, but commonly identified features include: exencephaly, limb defects, and either facial clefts or thoraco-abdominoschisis. The exact etiology remains uncertain, as the disorder has been regarded as sporadic with low recurrence. Vascular disruption during early embryogenesis, early amnion rupture, abnormal splitting of the embryo, and failure of amnion fusion have been implicated in the pathogenesis of LBWC. A role for possible gene mutation and maternal use of alcohol, tobacco, or illicit drugs has also been suggested. Detailed ultrasonography along with biochemical screening may allow for early detection.

  18. Differential potency of atropisomers of polychlorinated biphenyls on cytochrome P450 induction and uroporphyrin accumulation in the chick embryo hepatocyte culture.

    PubMed

    Rodman, L E; Shedlofsky, S I; Mannschreck, A; Püttmann, M; Swim, A T; Robertson, L W

    The atropisomers of 2,2',3,4,6-pentachlorobiphenyl (PeCB), 2,2',3,4,4',6-hexachlorobiphenyl (HeCB), and 2,2',3,3',4,4',6,6'-octachlorobiphenyl (OCB) were studied in the chick embryo hepatocyte culture to determine if chirality plays a role in the recognition events associated with the induction of cytochromes P450 and the accumulation of uroporphyrin (URO). Concentration-related induction of cytochrome P450 content, ethoxyresorufin-O-deethylase (EROD) and benzphetamine N-demethylase (BPDM) activities were measured. The rank order of potency for total cytochrome P450 induction was HeCB greater than OCB greater than or equal to PeCB. The (+)- and (-)-enantiomers of PeCB and OCB were of equal potencies as inducers of cytochromes P450, whereas the (+)-HeCB was greater than the (-)-HeCB. HeCB was a much more potent inducer of EROD activity than was either PeCB or OCB. EROD activity was induced to a much greater extent by the (+)-enantiomers of all compounds, with the (-)-enantiomers of PeCB and OCB being inactive. BPDM activity was induced by all three compounds in the order of OCB greater than or equal to HeCB greater than PeCB. The (-)-enantiomers were more potent inducers of BPDM activities than were the (+)-enantiomers, except for HeCB, in which the (+)- was more potent than the (-)-enantiomer. Analysis of porphyrin accumulation in cultures treated with delta-aminolevulinic acid revealed that (+)-HeCB caused the greatest percent URO accumulation, which also correlated with the greatest increase in EROD activity. All other enantiomers caused up to 47% URO accumulation, which did not correlate with an increase in EROD activity.

  19. Antibody response of patients after postexposure rabies vaccination with small intradermal doses of purified chick embryo cell vaccine or purified Vero cell rabies vaccine.

    PubMed Central

    Briggs, D. J.; Banzhoff, A.; Nicolay, U.; Sirikwin, S.; Dumavibhat, B.; Tongswas, S.; Wasi, C.

    2000-01-01

    Although the introduction of tissue culture vaccines for rabies has dramatically improved the immunogenicity and safety of rabies vaccines, they are often prohibitively expensive for developing countries. To examine whether smaller doses of these vaccines could be used, we tested the safety and immunogenicity of purified chick embryo cell vaccine (PCECV) on 211 patients in Thailand with World Health Organization (WHO) category II and III exposures to rabies. The patients presented at two Thai hospitals and were randomized into three groups. Patients in Group 1 received 0.1 ml PCECV intradermally at two sites on days 0, 3, 7, and at one site on days 30 and 90. Group 2 was treated similarly, except that purified Vero cell rabies vaccine (PVRV) was used instead of PCECV. Group 3 received 1.0 ml PCECV intramuscularly on days 0, 3, 7, 14, 30 and 90. After 0, 3, 7, 14, 30 and 90 days serum was collected from the subjects and the geometric mean titres (GMTs) of rabies virus neutralizing antibody determined. After 14 days the GMT of 59 patients vaccinated intradermally with PCECV was equivalent to that of patients who received PVRV. Adverse reactions were more frequent in patients who received vaccines intradermally, indicating the reactions were associated with the route of injection, rather than the vaccine per se. We conclude that PCECV is a safe and highly immunogenic vaccine for postexposure rabies vaccination when administered intradermally in 0.1-ml doses using the two-site method ("2,2,2,0,1,1") recommended by WHO. PMID:10859864

  20. Effects of the peroxisome proliferator di(2-ethylhexyl)phthalate on cell turnover and peroxisome proliferation in primary chick embryo hepatocytes.

    PubMed

    Arias, Elio

    2012-12-01

    The peroxisome proliferator (PP) di(2-ethylhexyl)phthalate (DEHP) is widely used as a plasticizer and can contaminate air, water, and soil. As yet, no data have been published on its potential to induce changes in cell growth of nonmammalian hepatocytes. In the present study, the effects of DEHP on cell turnover and induction of peroxisome proliferation were evaluated in primary hepatocyte cultures from chick embryos. Cells were treated after attachment with 0, 25, 50, 75, and 100 µM DEHP for up to 96 h. S-phase increased significantly (p < 0.01) from a background level of 5.5 ± 0.1% in solvent-control hepatocytes to a maximum level of 7.1 ± 0.1% in cells exposed for 48 h to 100 µM DEHP and decreased to near 6% by 96 h. Lower (p < 0.05) levels of induction were seen at 50 and 75 µM DEHP. Spontaneous apoptosis showed a slight (p < 0.05) decrease in hepatocytes treated with ≥75 µM dosages, as measured at 72 to 96 h. Induction of peroxisome proliferation was observed for cultures treated with ≥75 µM dosages at 48 h onwards. The results of the present study indicate that avian species may be responsive to the effects of PPs and may thus be affected by the presence of DEHP in the environment, but that this species is less sensitive than rodents.

  1. Evaluating the abnormal ossification in tibiotarsi of developing chick embryos exposed to 1.0ppm doses of platinum group metals by spectroscopic techniques.

    PubMed

    Stahler, Adam C; Monahan, Jennifer L; Dagher, Jessica M; Baker, Joshua D; Markopoulos, Marjorie M; Iragena, Diane B; NeJame, Britney M; Slaughter, Robert; Felker, Daniel; Burggraf, Larry W; Isaac, Leon A C; Grossie, David; Gagnon, Zofia E; Sizemore, Ioana E Pavel

    2013-04-01

    Platinum group metals (PGMs), i.e., palladium (Pd), platinum (Pt) and rhodium (Rh), are found at pollutant levels in the environment and are known to accumulate in plant and animal tissues. However, little is known about PGM toxicity. Our previous studies showed that chick embryos exposed to PGM concentrations of 1mL of 5.0ppm (LD50) and higher exhibited severe skeletal deformities. This work hypothesized that 1.0ppm doses of PGMs will negatively impact the mineralization process in tibiotarsi. One milliliter of 1.0ppm of Pd(II), Pt(IV), Rh(III) aqueous salt solutions and a PGM-mixture were injected into the air sac on the 7th and 14th day of incubation. Control groups with no-injection and vehicle injections were included. On the 20th day, embryos were sacrificed to analyze the PGM effects on tibiotarsi using four spectroscopic techniques. 1) Micro-Raman imaging: Hyperspectral Raman data were collected on paraffin embedded cross-sections of tibiotarsi, and processed using in-house-written MATLAB codes. Micro-Raman univariate images that were created from the ν1(PO4(3-)) integrated areas revealed anomalous mineral inclusions within the bone marrow for the PGM-mixture treatment. The age of the mineral crystals (ν(CO3(2-))/ν1(PO4(3-))) was statistically lower for all treatments when compared to controls (p≤0.05). 2) FAAS: The percent calcium content of the chemically digested tibiotarsi in the Pd and Pt groups changed by ~45% with respect to the no-injection control (16.1±0.2%). 3) Micro-XRF imaging: Abnormal calcium and phosphorus inclusions were found within the inner longitudinal sections of tibiotarsi for the PGM-mixture treatment. A clear increase in the mineral content was observed for the outer sections of the Pd treatment. 4) ICP-OES: PGM concentrations in tibiotarsi were undetectable (<5ppb). The spectroscopic techniques gave corroborating results, confirmed the hypothesis, and explained the observed pathological (skeletal developmental abnormalities

  2. An oxygenated metabolite of benzo[a]pyrene increases hepatic β-oxidation of fatty acids in chick embryos.

    PubMed

    Westman, Ola; Larsson, Maria; Venizelos, Nikolaos; Hollert, Henner; Engwall, Magnus

    2014-05-01

    Polycyclic aromatic hydrocarbons (PAHs) are well-known carcinogens to humans and ecotoxicological effects have been shown in several studies. However, PAHs can also be oxidized into more water soluble-oxygenated metabolites (Oxy-PAHs). The first purpose of the present project was to (1) assess the effects of a mixture containing three parent PAHs: anthracene, benz[a]anthracene, and benzo[a]pyrene versus a mixture of their oxygenated metabolites, namely: anthracene-9,10-dione, benz[a]anthracene-7,12-dione, and 9,10-dihydrobenzo[a]pyrene-7-(8H)-one on the hepatic fatty acid β-oxidation in chicken embryos (Gallus gallus domesticus) exposed in ovo. The second and also main purpose of the project was to (2) assess the effects of the parent PAHs versus their oxy-PAHs analogues when injected individually, followed by (3) additional testing of the individual oxy-PAHs. The hepatic β-oxidation was measured using a tritium release assay with [9,10-(3)H]-palmitic acid (16:0) as substrate. The result from the first part (1) showed reduced hepatic β-oxidation after exposure in ovo to a mixture of three PAHs, however, increased after exposure to the mixture of three oxy-PAHs compared to control. The result from the second part (2) and also the follow-up experiment (3) showed that 9,10-dihydrobenzo[a]pyrene-7-(8H)-one was the causative oxy-PAH. The implication of this finding on the risk assessment of PAH metabolite exposure in avian wildlife remains to be determined. To the best of our knowledge, no similar studies have been reported.

  3. Day-1 chick development.

    PubMed

    Sheng, Guojun

    2014-03-01

    The first day of chick development takes place inside the mother hen (in utero), during which the embryo progresses from fertilization to late blastula/early gastrula formation. The salient features of developmental anatomy in this period are conserved among the sauropsids (birds and reptiles). Many of these features are also shared in prototherian (monotreme) embryos, whereas metatherian (marsupial) and eutherian (placental) embryos display significant variations. Important for understanding the evolution of early development in amniotes, the knowledge of cellular and molecular mechanisms regulating in utero chick development may also offer valuable insight into early lineage specification in prototherians and conserved features in mammalian early development. This commentary provides a snapshot of what is currently known about intrauterine chick development and identifies key issues that await further clarification, including the process of cellularization, allocation of maternal determinants, zygotic gene activation, mid-blastula transition, cell layer increase and reduction, radial symmetry breaking, early lineage segregation, and role of yolk syncytium in early patterning. PMID:24550174

  4. Cell proliferation during early development of the chick embryo otic anlage: quantitative comparison of migratory and nonmigratory regions of the otic epithelium.

    PubMed

    Alvarez, I S; Martín-Partido, G; Rodríguez-Gallardo, L; González-Ramos, C; Navascués, J

    1989-12-01

    During development of the otic anlage, a certain proportion of epithelial cells migrate toward the mesenchymal compartment to form part of the acoustic-vestibular ganglion. The migrating cells are observed only in the zone of the otic anlage that will make contact with the acoustic-vestibular ganglion (so-called ganglion zone). In Hamburger and Hamilton's stages 13 to 16, the number of epithelial cells that migrate is relatively low, but it becomes steadily higher from stage 17 on. In the otic anlage of chick embryos, between developmental stages 9 and 21 (48 to 94 hours of incubation), mitotic index, apical or basal localization within the epithelium of dividing cells, and orientation of the mitotic spindles were analyzed. These features in the ganglion zone were compared with observations in the rest of the otic epithelium, where migratory processes do not take place. In stages 13 to 15, when few epithelial cells are migrating, the mitotic index (MI) in the ganglion zone of the otic anlage is similar to that in nonmigratory regions. In more advanced stages, however, when cell migration becomes accelerated, the MI in the migratory zone of the otic wall is significantly higher than that in the rest of the otic epithelium. This suggests an intimate relationship between the migration of otic epithelial cells and a high rate of cell proliferation, the possible nature of which is discussed. Although the majority of mitoses in the otic anlage are located at the apical surface of the epithelium, from stage 13 onward, a few dividing cells are seen in the basal third of the epithelium. Furthermore, these basal mitoses appear exclusively in the migratory zone of the otic anlage, thus suggesting a possible relationship between epithelial cell migration and basal mitosis. During the developmental period prior to stage 18, no significant differences in mitotic spindle orientation are noted between migratory and nonmigratory zones of the otic anlage. In contrast, in stages of

  5. [Ratio of concentration of ions of uni- and bivalent metals in the tissues of developing chick embryos and 1-day-old chickens].

    PubMed

    Kudriavtseva, G V; Kolotilova, A I; Govorova, L V; Redikh, S V; Bulavko, N I

    1976-01-01

    The ratio of concentrations Na+/K+ decreases in the brain and liver and increases in the cardiac muscle during the chick embryogenesis. The maximum concentration of Ca2+ was noted in the tissues under study on 14th day of chick embryonic development and its content decreased reliably at the subsequent stages. The concentration of Mg2+ in the tissues under study decreased during the embryogenesis as well.

  6. Harvesting clues from genome wide transcriptome analysis for exploring thalidomide mediated anomalies in eye development of chick embryo: Nitric oxide rectifies the thalidomide mediated anomalies by swinging back the system to normal transcriptome pattern.

    PubMed

    Kumar, Pavitra; Kasiviswanathan, Dharanibalan; Sundaresan, Lakshmikirupa; Kathirvel, Priyadarshan; Veeriah, Vimal; Dutta, Priya; Sankaranarayanan, Kavitha; Gupta, Ravi; Chatterjee, Suvro

    2016-02-01

    Thalidomide, the notorious teratogen is known to cause various developmental abnormalities, among which a range of eye deformations are very common. From the clinical point of view, it is necessary to pinpoint the mechanisms of teratogens that tune the gene expression. However, to our knowledge, the molecular basis of eye deformities under thalidomide treatmenthas not been reported so far. Present study focuses on the possible mechanism by which thalidomide affects eye development and the role of Nitric Oxide in recovering thalidomide-mediated anomalies of eye development using chick embryo and zebrafish models with transcriptome analysis. Transcriptome analysis showed that 403 genes were up-regulated and 223 genes were down-regulated significantly in thalidomide pre-treated embryos. 8% of the significantly modulated genes have been implicated in eye development including Pax6, OTX2, Dkk1 and Shh. A wide range of biological process and molecular function was affected by thalidomide exposure. Biological Processes including structural constituent of eye lens and Molecular functions such as visual perception and retinal metabolic process formed strong annotation clustersindicating the adverse effects of thalidomide on eye development and function. Here, we have discussed the whole embryo transcriptome with the expression of PAX6, SOX2, and CRYAAgenes from developing eyes. Our experimental data showing structural and functional aspects includingeye size, lens transparency and optic nerve activity and bioinformatics analyses of transcriptome suggest that NO could partially protect thalidomide treated embryos from its devastating effects on eye development and function. PMID:26717904

  7. Harvesting clues from genome wide transcriptome analysis for exploring thalidomide mediated anomalies in eye development of chick embryo: Nitric oxide rectifies the thalidomide mediated anomalies by swinging back the system to normal transcriptome pattern.

    PubMed

    Kumar, Pavitra; Kasiviswanathan, Dharanibalan; Sundaresan, Lakshmikirupa; Kathirvel, Priyadarshan; Veeriah, Vimal; Dutta, Priya; Sankaranarayanan, Kavitha; Gupta, Ravi; Chatterjee, Suvro

    2016-02-01

    Thalidomide, the notorious teratogen is known to cause various developmental abnormalities, among which a range of eye deformations are very common. From the clinical point of view, it is necessary to pinpoint the mechanisms of teratogens that tune the gene expression. However, to our knowledge, the molecular basis of eye deformities under thalidomide treatmenthas not been reported so far. Present study focuses on the possible mechanism by which thalidomide affects eye development and the role of Nitric Oxide in recovering thalidomide-mediated anomalies of eye development using chick embryo and zebrafish models with transcriptome analysis. Transcriptome analysis showed that 403 genes were up-regulated and 223 genes were down-regulated significantly in thalidomide pre-treated embryos. 8% of the significantly modulated genes have been implicated in eye development including Pax6, OTX2, Dkk1 and Shh. A wide range of biological process and molecular function was affected by thalidomide exposure. Biological Processes including structural constituent of eye lens and Molecular functions such as visual perception and retinal metabolic process formed strong annotation clustersindicating the adverse effects of thalidomide on eye development and function. Here, we have discussed the whole embryo transcriptome with the expression of PAX6, SOX2, and CRYAAgenes from developing eyes. Our experimental data showing structural and functional aspects includingeye size, lens transparency and optic nerve activity and bioinformatics analyses of transcriptome suggest that NO could partially protect thalidomide treated embryos from its devastating effects on eye development and function.

  8. MHC class I target recognition, immunophenotypes and proteomic profiles of natural killer cells within the spleens of day-14 chick embryos

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chicken natural killer (NK) cells are not well defined, so little is known about the molecular interactions controlling their activity. At day 14 of embryonic development, chick spleens are a rich source of T-cellfree CD8aa+, CD3_ cells with natural killing activity. Cell-mediated cytotoxicity assay...

  9. Retina regeneration in the chick embryo is not induced by spontaneous Mitf downregulation but requires FGF/FGFR/MEK/Erk dependent upregulation of Pax6

    PubMed Central

    Aycinena, Juan-Carlos

    2007-01-01

    Purpose To elucidate the early cellular events that take place during induction of retina regeneration in the embryonic chick, focusing on the relationship between fibroblast growth factor (FGF) signaling and the regulation of Pax6 and Mitf. Methods The retina of embryonic day 4 (E4) chicks was removed and a heparin coated bead soaked in fibroblast growth factor 2 (FGF2) was placed into the optic cup. The pharmacological inhibitor PD173074 was used to inhibit FGF receptors, PD98059 was used to inhibit MAP kinase-kinase/extracellular signal-regulated kinase (MEK/Erk) signaling. Retroviral constructs for paired box 6 (Pax6), MEK, and microphthalmia (Mitf) were also used in overexpression studies. Immunohistochemistry was used to examine pErk, Pax6, Mitf, and melanosomal matrix protein 115 (MMP115) immunoreactivity and bromodeoxyuridine (BrdU) incorporation at different time points after removing the retina. Results The embryonic chick has the ability to regenerate a new retina by the process of transdifferentiation of the retinal pigment epithelium (RPE). We observed that during the induction of transdifferentiation, downregulation of Mitf was not sufficient to induce transdifferentiation at E4 and that FGF2 was required to drive Pax6 protein expression and cell proliferation, both of which are necessary for transdifferentiation. Furthermore, we show that FGF2 works through the FGFR/MEK/Erk signaling cascade to increase Pax6 expression and proliferation. Ectopic Mitf expression was able to inhibit transdifferentiation by acting downstream of FGFR/MEK/Erk signaling, likely by inhibiting the increase in Pax6 protein in the RPE. Conclusions FGF2 stimulates Pax6 expression during induction of transdifferentiation of the RPE through FGFR/MEK/Erk signaling cascade. This Pax6 expression is accompanied by an increase in BrdU incorporation. In addition, we show that Mitf is spontaneously downregulated after removal of the retina even in the absence of FGF2. This Mitf

  10. Gc protein-derived macrophage-activating factor (GcMAF) stimulates cAMP formation in human mononuclear cells and inhibits angiogenesis in chick embryo chorionallantoic membrane assay.

    PubMed

    Pacini, Stefania; Morucci, Gabriele; Punzi, Tiziana; Gulisano, Massimo; Ruggiero, Marco

    2011-04-01

    The effects of Gc protein-derived macrophage-activating factor (GcMAF) have been studied in cancer and other conditions where angiogenesis is deregulated. In this study, we demonstrate for the first time that the mitogenic response of human peripheral blood mononuclear cells (PBMCs) to GcMAF was associated with 3'-5'-cyclic adenosine monophosphate (cAMP) formation. The effect was dose dependent, and maximal stimulation was achieved using 0.1 ng/ml. Heparin inhibited the stimulatory effect of GcMAF on PBMCs. In addition, we demonstrate that GcMAF (1 ng/ml) inhibited prostaglandin E(1)- and human breast cancer cell-stimulated angiogenesis in chick embryo chorionallantoic membrane (CAM) assay. Finally, we tested different GcMAF preparations on CAM, and the assay proved to be a reliable, reproducible and inexpensive method to determine the relative potencies of different preparations and their stability; we observed that storage at room temperature for 15 days decreased GcMAF potency by about 50%. These data could prove useful for upcoming clinical trials on GcMAF. PMID:21170647

  11. Chicken interferome: avian interferon-stimulated genes identified by microarray and RNA-seq of primary chick embryo fibroblasts treated with a chicken type I interferon (IFN-α).

    PubMed

    Giotis, Efstathios S; Robey, Rebecca C; Skinner, Natalie G; Tomlinson, Christopher D; Goodbourn, Stephen; Skinner, Michael A

    2016-08-05

    Viruses that infect birds pose major threats-to the global supply of chicken, the major, universally-acceptable meat, and as zoonotic agents (e.g. avian influenza viruses H5N1 and H7N9). Controlling these viruses in birds as well as understanding their emergence into, and transmission amongst, humans will require considerable ingenuity and understanding of how different species defend themselves. The type I interferon-coordinated response constitutes the major antiviral innate defence. Although interferon was discovered in chicken cells, details of the response, particularly the identity of hundreds of stimulated genes, are far better described in mammals. Viruses induce interferon-stimulated genes but they also regulate the expression of many hundreds of cellular metabolic and structural genes to facilitate their replication. This study focusses on the potentially anti-viral genes by identifying those induced just by interferon in primary chick embryo fibroblasts. Three transcriptomic technologies were exploited: RNA-seq, a classical 3'-biased chicken microarray and a high density, "sense target", whole transcriptome chicken microarray, with each recognising 120-150 regulated genes (curated for duplication and incorrect assignment of some microarray probesets). Overall, the results are considered robust because 128 of the compiled, curated list of 193 regulated genes were detected by two, or more, of the technologies.

  12. Chicken interferome: avian interferon-stimulated genes identified by microarray and RNA-seq of primary chick embryo fibroblasts treated with a chicken type I interferon (IFN-α).

    PubMed

    Giotis, Efstathios S; Robey, Rebecca C; Skinner, Natalie G; Tomlinson, Christopher D; Goodbourn, Stephen; Skinner, Michael A

    2016-01-01

    Viruses that infect birds pose major threats-to the global supply of chicken, the major, universally-acceptable meat, and as zoonotic agents (e.g. avian influenza viruses H5N1 and H7N9). Controlling these viruses in birds as well as understanding their emergence into, and transmission amongst, humans will require considerable ingenuity and understanding of how different species defend themselves. The type I interferon-coordinated response constitutes the major antiviral innate defence. Although interferon was discovered in chicken cells, details of the response, particularly the identity of hundreds of stimulated genes, are far better described in mammals. Viruses induce interferon-stimulated genes but they also regulate the expression of many hundreds of cellular metabolic and structural genes to facilitate their replication. This study focusses on the potentially anti-viral genes by identifying those induced just by interferon in primary chick embryo fibroblasts. Three transcriptomic technologies were exploited: RNA-seq, a classical 3'-biased chicken microarray and a high density, "sense target", whole transcriptome chicken microarray, with each recognising 120-150 regulated genes (curated for duplication and incorrect assignment of some microarray probesets). Overall, the results are considered robust because 128 of the compiled, curated list of 193 regulated genes were detected by two, or more, of the technologies. PMID:27494935

  13. 3,5,3'-triiodothyronine (T3) stimulates cell proliferation through the activation of the PI3K/Akt pathway and reactive oxygen species (ROS) production in chick embryo hepatocytes.

    PubMed

    Gnocchi, Davide; Leoni, Silvia; Incerpi, Sandra; Bruscalupi, Giovannella

    2012-05-01

    Thyroid hormones (THs) have a wide variety of essential roles in vertebrates, ranging from the regulation of key metabolic processes to cell proliferation and apoptosis. The classical mechanism of action of THs is genomic; 3,5,3'-triiodothyronine (T3) binds to specific nuclear receptors (TRs) and modifies the expression of specific genes. Recently, a new category of mechanisms, termed nongenomic, has been discovered for T3. These mechanisms include, among others, the rapid activation of signal transduction pathways, such as PI3K/Akt and MAPK, which eventually lead to cell proliferation. These effects are mediated in some cell types by a plasma membrane receptor, identified as integrin αvβ3, and in other cell types by cytoplasmic TRβ1. The aim of this work was to analyze the effect of T3 on the cell growth of chick embryo hepatocytes at two different stages of development, 14 and 19 days, and to determine the activation of the signal transduction pathways, focusing on the potential involvement of a plasma membrane receptor and the possible participation of PI3K/Akt and reactive oxygen species (ROS). Our results clearly show that T3 stimulates cell proliferation at both stages of development through the activation of the PI3K/Akt pathway and the production of small amounts of ROS, which operate as effective second messengers. Moreover, we prove that these effects are not initiated at the plasma membrane receptor for T3.

  14. Morphological and quantitative studies in the otic region of the neural tube in chick embryos suggest a neuroectodermal origin for the otic placode

    PubMed Central

    MAYORDOMO, RAQUEL; RODRÍGUEZ-GALLARDO, LUCÍA; ALVAREZ, IGNACIO S.

    1998-01-01

    Careful histological observation of the development of the anlage of the inner ear in chicken embryos led us to question the traditional view of otic placode (OP) formation. First, morphological studies in the cephalic region carried out on stages preceding the appearance of the placodal epithelium revealed that the medial placodal cells are continuous temporally and spatially with cells belonging to the neural fold (NF). Second, both the formation of the basal lamina between the dorsal region of the neural tube (NT) and ectoderm and the pattern of formation of the neural crest present distinctive characteristics between otic levels and regions located anteriorly and posteriorly. Third, numerical comparisons of parameters for the NT and the OP between different levels of the rhombencephalon allowed us to assign a differential behaviour in the growth pattern of the otic region. These results indicated that the medial part of the OP is not derived from already independent ectoderm that increases in thickness under the influence of the NT (as previously accepted) but that it develops directly from the NFs. Although we do not exclude other possibilities, we propose that at least a proportion of the OP cells originate directly from cells committed to be neural crest. After this incorporation, basal laminal formation would delimit the NT from the OP without transition of the otic cells to ectoderm. This hypothesis would imply that part of the otic cells originate directly from neuroepithelial cells having a neuroectodermal (rather than the previously established ectodermal) origin. PMID:9758135

  15. Chick development and high dose of bendiocarb.

    PubMed

    Petrovova, Eva; Sedmera, David; Luptakova, Lenka; Mazensky, David; Danko, Jan

    2012-01-01

    Developmental data of carbamate pesticides are scarce although they generally possess low toxicity for vertebrates. The aim of the study was to investigate the toxicity of bendiocarb to liver and central nervous system of chick embryos. Bendiocarb (1600 μg/egg) was administered to the embryo through membrana papyracea on embryonic day 3 and 10. In the liver and central nervous system we observed no macroscopic or microscopic changes. These organs were also investigated for caspase activity in regard to application of bendiocarb and no differences in the caspase immunopositivity were observed in comparison with the control. The embryolethality after bendiocarb respective dose was high (94 %) on the embryonic day 3, though following results indicated no toxicity to investigated organs and no increase in the number of apoptotic cells in survived chick embryos on both the early (day 3 of incubation) and the later (day 10 of incubation) developmental stage. PMID:22540656

  16. cAMP and in vivo hypoxia induce tob, ifr1, and fos expression in erythroid cells of the chick embryo.

    PubMed

    Dragon, Stefanie; Offenhäuser, Nina; Baumann, Rosemarie

    2002-04-01

    During avian embryonic development, terminal erythroid differentiation occurs in the circulation. Some of the key events, such as the induction of erythroid 2,3-bisphosphoglycerate (2,3-BPG), carbonic anhydrase (CAII), and pyrimidine 5'-nucleotidase (P5N) synthesis are oxygen dependent (Baumann R, Haller EA, Schöning U, and Weber M, Dev Biol 116: 548-551, 1986; Dragon S and Baumann R, Am J Physiol Regulatory Integrative Comp Physiol 280: R870-R878, 2001; Dragon S, Carey C, Martin K, and Baumann R, J Exp Biol 202: 2787-2795, 1999; Dragon S, Glombitza S, Götz R, and Baumann R, Am J Physiol Regulatory Integrative Comp Physiol 271: R982-R989, 1996; Dragon S, Hille R, Götz R, and Baumann R, Blood 91: 3052-3058, 1998; Million D, Zillner P, and Baumann R, Am J Physiol Regulatory Integrative Comp Physiol 261: R1188-R1196, 1991) in an indirect way: hypoxia stimulates the release of norepinephrine (NE)/adenosine into the circulation (Dragon et al., J Exp Biol 202: 2787-2795, 1999; Dragon et al., Am J Physiol Regulatory Integrative Comp Physiol 271: R982-R989, 1996). This leads via erythroid beta-adrenergic/adenosine A(2) receptor activation to a cAMP signal inducing several proteins in a transcription-dependent manner (Dragon et al., Am J Physiol Regulatory Integrative Comp Physiol 271: R982-R989, 1996; Dragon et al., Blood 91: 3052-3058, 1998; Glombitza S, Dragon S, Berghammer M, Pannermayr M, and Baumann R, Am J Physiol Regulatory Integrative Comp Physiol 271: R973-R981, 1996). To understand how the cAMP-dependent processes are initiated, we screened an erythroid cDNA library for cAMP-regulated genes. We detected three genes that were strongly upregulated (>5-fold) by cAMP in definitive and primitive red blood cells. They are homologous to the mammalian Tob, Ifr1, and Fos proteins. In addition, the genes are induced in the intact embryo during short-term hypoxia. Because the genes are regulators of proliferation and differentiation in other cell types, we suggest that c

  17. Tgfβ2 and 3 are coexpressed with their extracellular regulator Ltbp1 in the early limb bud and modulate mesodermal outgrowth and BMP signaling in chicken embryos

    PubMed Central

    2010-01-01

    Background Transforming growth factor β proteins (Tgfβs) are secreted cytokines with well-defined functions in the differentiation of the musculoskeletal system of the developing limb. Here we have studied in chicken embryos, whether these cytokines are implicated in the development of the embryonic limb bud at stages preceding tissue differentiation. Results Immunohistochemical detection of phosphorylated Smad2 and Smad3 indicates that signaling by this pathway is active in the undifferentiated mesoderm and AER. Gene expression analysis shows that transcripts of tgfβ2 and tgfβ3 but not tgfβ1 are abundant in the growing undifferentiated limb mesoderm. Transcripts of tgfβ2 are also found in the AER, which is the signaling center responsible for limb outgrowth. Furthermore, we show that Latent Tgfβ Binding protein 1 (LTBP1), which is a key extracellular modulator of Tgfβ ligand bioavailability, is coexpressed with Tgfβs in the early limb bud. Administration of exogenous Tgfβs to limb buds growing in explant cultures provides evidence of these cytokines playing a role in the regulation of mesodermal limb proliferation. In addition, analysis of gene regulation in these experiments revealed that Tgfβ signaling has no effect on the expression of master genes of musculoskeletal tissue differentiation but negatively regulates the expression of the BMP-antagonist Gremlin. Conclusion We propose the occurrence of an interplay between Tgfβ and BMP signaling functionally associated with the regulation of early limb outgrowth by modulating limb mesenchymal cell proliferation. PMID:20565961

  18. Retroviral Vector-Mediated Gene Transfer into the Chick Optic Vesicle by In Ovo Electroporation

    NASA Astrophysics Data System (ADS)

    Sakuta, Hiraki; Suzuki, Ryoko; Noda, Masaharu

    The chick embryo offers many advantages for developmental studies over other vertebrate embryos as it allows easy access for in ovo surgical manipulations, such as tissue transplantation and the implantation of cultured cells or chemically treated beads for the local release of humoral factors. In particular, owing to its external position in the embryo, the chick eye is a popular model for studying the patterning mechanism of the central nervous system (CNS). This patterning has a crucial role in shaping functional organization because it is the basis of the specific wiring in the CNS. Genetic analysis is not easy in the chick, as compared with the mouse for which transgene introduction or gene targeting techniques have been well established. However, because methods for the expression of exogenous genes and for gene silencing in the chick embryo have been recently developed, the functional analysis of genes has become possible in combination with classical techniques of developmental biology and neurobiology.

  19. Embryotoxic effects of crude oil in mallard ducks and chicks

    USGS Publications Warehouse

    Hoffman, D.J.

    1978-01-01

    Recent studies in this laboratory have revealed that surface applications of microliter amounts of some crude and fuel oils that coat less than 10% of the egg surface reduce hatching considerably in different avian species. Applications of paraffin compounds that coat equal areas of the egg surface do not reduce hatching suggesting that toxicity is due to causes other than asphyxia. In the present study, 1?10 :l of South Louisiana crude oil, an API reference oil, were applied to the surface of fertile mallard (Anas platyrhynchos) and chicken (Gallus gallus) eggs. Early embryolethality was greater in mallard embryos than in chick embryos, but later embryolethality that coincided with the time of rapid outgrowth of the chorioallantoic membrane was more prevalent in chick embryos. The overall incidence of embryolethality was similar in both species. Retardation of growth as reflected by embryonic body weight, crown-rump length, beak length, and general appearance was more pronounced in chick than mallard embryos. Teratogenic defects were more frequent in chick embryos, and incomplete or abnormal ossification of the skull was the most common. External application of equivalent amounts of a mixture of paraffin compounds present in crude oil had virtually no embryotoxic effects in either species, suggesting that other components including aromatic hydrocarbons and organometallics may cause the embryotoxicity.

  20. Sources of trophic factors that induce limb regeneration and prevent amputation-induced neuronal death.

    PubMed

    Sisken, B F; Fowler, I; Barr, E

    1986-06-01

    Segments of 2-, 4-, 6- and 8-day neural tube, or of 15-day peripheral nerve were implanted longitudinally into limb stumps of 4-day chick embryos whose right-wing buds were amputated at the future elbow region. Stumps of amputated limbs (ALs) implanted with 7-day heart or without implant served as controls. Effects of progressively older neural tube implants (NTIs) upon ALs and host spinal cord neurons were analyzed by area measurements of the peripheral limb field (PLF) and NTI and by cell counts of the host lateral motor column (LMC). Nine days postamputation, 2- and 4-day NTIs contained many neurons and induced epimorphic regeneration in more than one-fourth of the embryos. Six-day NTIs contained few neurons and induced only tissue regeneration. Eight-day NTIs and peripheral nerve containing only non-neuronal cells were as ineffective as controls in stimulating regeneration, although peripheral nerve did cause a significant increase in the peripheral field. The NTIs of all ages and implants of peripheral nerve were equally effective in protecting LMC neurons from amputation-induced cell death in the host spinal cord. The results may indicate that neurons of the implant induce limb regeneration and non-neuronal cells of the implant protect against LMC neuronal death.

  1. Modeling Chick to Assess Diabetes Pathogenesis and Treatment

    PubMed Central

    Datar, Savita P.; Bhonde, Ramesh R.

    2011-01-01

    Animal models have been used extensively in diabetes research. Studies on animal models have contributed to the discovery and purification of insulin, development of new therapeutic approaches, and progress in fundamental and clinical research. However, conventional rodent and large animal mammalian models face ethical, practical, or technical limitations. Therefore, it would be beneficial developing an alternative model for diabetes research which would overcome these limitations. Amongst other vertebrates, birds are phylogenically closer to mammals, and amongst birds, the chick has been used as one of the favored models in developmental biology, toxicology, cancer research, immunology, and drug testing. Chicken eggs are readily available, have a short incubation period and easily accessible embryos. Based on these inimitable advantages, the present review article aims to discuss the suitability of the chick as a model system to study specific aspects of diabetes. The review focuses on the application of i) chick pancreatic islets for screening of antidiabetic agents and for islet banking, (ii) shell-less chick embryo culture as a model to study hyperglycemia-induced malformations observed in mammalian embryos, and (iii) chick chorioallantoic membrane (CAM) to examine glucose-induced endothelial damage leading to inhibition of angiogenesis. PMID:22189547

  2. Activation patterns of embryonic chick lumbosacral motoneurones following large spinal cord reversals.

    PubMed Central

    Vogel, M W

    1987-01-01

    1. Embryonic chick motoneurones were caused to innervate inappropriate hindlimb muscles by rotating the presumptive lumbosacral region of the neural tube in stage 15-16 embryos which is prior to the outgrowth of motoneurone axons. 2. The activation patterns of motoneurones in control and spinal cord reversal embryos were analysed from electromyographic (e.m.g.) recordings of stage 36 limb muscles during evoked movement sequences in an isolated spinal cord-limb preparation. Histograms representing the frequency of activation were constructed for each muscle. The muscle's pattern of activation was classified as flexor-like or extensor-like and compared to the activation patterns of control muscles. 3. A series of control operations was performed in which the prospective lumbosacral region of the neural tube was removed and replaced in its original orientation. Muscles in these embryos were innervated by their normal motoneurone pools and they were activated normally, indicating that the neural tube operation per se does not alter the activation pattern of motoneurones. Furthermore, some muscles (twelve out of sixty-one) in spinal cord reversal embryos had normal activation patterns and appeared to be innervated by their original motoneurones. Based on these results and the result of a previous study (Landmesser & O'Donovan, 1984 b), it is concluded that motoneurones in reversed spinal cords are activated in a manner appropriate for their original identity. 4. The majority of muscles (thirty-three out of sixty-one) in large spinal cord reversal embryos were activated during an appropriate phase of the kicking cycle. Of the remaining muscles, 16% were activated inappropriately (i.e. extensor muscles were activated as flexors, and vice versa), and 30% had a novel 'mixed' flexor- and extensor-like activation pattern. However, the activation pattern of most muscles differed markedly from that of any other control muscles regardless of whether the muscle was activated

  3. Using chicken embryos for teratology studies.

    PubMed

    Henshel, Diane S; DeWitt, Jamie; Troutman, Andrea

    2003-02-01

    This unit describes methods for injecting, incubating, handling and analyzing domestic chicken embryos used in teratology studies. It also includes a discussion of caveats and special handling issues as well as some discussion of statistical analyses that differentiate working with chicken embryos from working with clutches of eggs or litters of pups. As an example of potential data, preliminary data from a study of abnormalities in early embryos and hatchling chicks exposed to chlordane are presented.

  4. Angiogenesis is repressed by ethanol exposure during chick embryonic development.

    PubMed

    Wang, Guang; Zhong, Shan; Zhang, Shi-yao; Ma, Zheng-lai; Chen, Jian-long; Lu, Wen-hui; Cheng, Xin; Chuai, Manli; Lee, Kenneth Ka Ho; Lu, Da-xiang; Yang, Xuesong

    2016-05-01

    It is now known that excess alcohol consumption during pregnancy can cause fetal alcohol syndrome to develop. However, it is not known whether excess ethanol exposure could directly affect angiogenesis in the embryo or angiogenesis being indirectly affected because of ethanol-induced fetal alcohol syndrome. Using the chick yolk sac membrane (YSM) model, we demonstrated that ethanol exposure dramatically inhibited angiogenesis in the YSM of 9-day-old chick embryos, in a dose-dependent manner. Likewise, the anti-angiogenesis effect of ethanol could be seen in the developing vessel plexus (at the same extra-embryonic regions) during earlier stages of embryo development. The anti-angiogenic effect of ethanol was found associated with excess reactive oxygen species (ROS) production; as glutathione peroxidase activity increased while superoxide dismutase 1 and 2 activities decreased in the YSMs. We further validated this observation by exposing chick embryos to 2,2'-azobis-amidinopropane dihydrochloride (a ROS inducer) and obtained a similar anti-angiogenesis effect as ethanol treatment. Semiquantitative reverse transcription-polymerase chain reaction analysis of the experimental YSMs revealed that expression of angiogenesis-related genes, vascular endothelial growth factor and its receptor, fibroblast growth factor 2 and hypoxia-inducible factor, were all repressed following ethanol and 2,2'-azobis-amidinopropane dihydrochloride treatment. In summary, our results suggest that excess ethanol exposure inhibits embryonic angiogenesis through promoting superfluous ROS production during embryo development. PMID:26177723

  5. Interdigital cell death in the embryonic limb is associated with depletion of Reelin in the extracellular matrix

    PubMed Central

    Díaz-Mendoza, M J; Lorda-Diez, C I; Montero, J A; García-Porrero, J A; Hurlé, J M

    2013-01-01

    Interdigital cell death is a physiological regression process responsible for sculpturing the digits in the embryonic vertebrate limb. Changes in the intensity of this degenerative process account for the different patterns of interdigital webbing among vertebrate species. Here, we show that Reelin is present in the extracellular matrix of the interdigital mesoderm of chick and mouse embryos during the developmental stages of digit formation. Reelin is a large extracellular glycoprotein which has important functions in the developing nervous system, including neuronal survival; however, the significance of Reelin in other systems has received very little attention. We show that reelin expression becomes intensely downregulated in both the chick and mouse interdigits preceding the establishment of the areas of interdigital cell death. Furthermore, fibroblast growth factors, which are cell survival signals for the interdigital mesoderm, intensely upregulated reelin expression, while BMPs, which are proapototic signals, downregulate its expression in the interdigit. Gene silencing experiments of reelin gene or its intracellular effector Dab-1 confirmed the implication of Reelin signaling as a survival factor for the limb undifferentiated mesoderm. We found that Reelin activates canonical survival pathways in the limb mesoderm involving protein kinase B and focal adhesion kinase. Our findings support that Reelin plays a role in interdigital cell death, and suggests that anoikis (apoptosis secondary to loss of cell adhesion) may be involved in this process. PMID:24030152

  6. Development of the chick thymus microenvironment: a study by lectin histochemistry.

    PubMed Central

    Fernandez, J G; Sanchez, A J; Melcon, C; Chamorro, C A; Garcia, C; Paz, P

    1994-01-01

    The microenvironment of the chick thymus has been examined during development using lectin histochemistry. We have assayed WGA, Con A, RCA-I and TPA on thymic sections from 13, 15, 17 and 19 d chick embryos and 0, 5, 10 and 15 d chicks. All lectins were immunoperoxidase and colloidal gold-conjugated for transmission electron microscope observations. WGA labelled both the cortical and medullary thymic stroma at all the stages analysed. An intense reaction to WGA was observed in the subcortical region from stage 18 embryos to 5 d chicks. On the other hand, WGA did not stain medullary areas of the chick thymus. Con A lectin detected several cell clusters of stromal cells and thymocytes in cortical regions. These clusters could represent a lymphostromal complex with which Con A receptors are associated, probably in relation to cell adhesion. The residues detected by RCA were distributed both in stromal cells and thymocytes of the developing chick thymus. There was an increase of the reaction to RCA between the 19 d embryos and the 5 d chicks. This increase might be interpreted in terms of the secretion of thymic humoral factors at these stages. The thymic stromal cells stained with immunoperoxidase conjugated-TPA showed a reticular pattern in the medulla. There is a possibility that the fucosyl residues may be expressed in the Ia antigen as has previously been suggested in other species. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:7512541

  7. Diverse range of fixed positional deformities and bone growth restraint provoked by flaccid paralysis in embryonic chicks

    PubMed Central

    Lamb, Katherine J; Lewthwaite, Jo C; Lin, Jean-Pierre; Simon, Dominic; Kavanagh, Emma; Wheeler-Jones, Caroline P D; Pitsillides, Andrew A

    2003-01-01

    Pancuronium bromide (PB) is used in neonates and pregnant women to induce limp, flaccid paralysis in order to allow mechanical ventilation during intensive care. Such non-depolarizing neuromuscular blocking drugs are administered to 0.1% of all human births in the UK. In this study, we examined PB effects on skeletal development in chick embryos. PB treatment produced skeletal deformities associated with significant reduction in longitudinal growth of all appendicular elements. This was associated with greater cartilage to bone ratios, indicating a preferential reduction in osteogenesis. PB also increased the incidence of knee joint flexion and tibiotarsal joint hyperextension. In addition to limb, spinal and craniofacial deformities, flaccid immobility appears to convert the normal geometric pattern of weight gain to a simple arithmetic accretion. This novel study highlights the potentially harmful effects of pharmacologically induced flaccid immobility on chick embryonic skeletal development. Whilst in ovo avian development clearly differs from human, our findings may have implications for the fetus, premature and term neonate receiving such non-depolarizing neuromuscular blocking drugs. PMID:14632633

  8. Avian embryo monitoring during incubation using multi-channel diffuse speckle contrast analysis.

    PubMed

    Yeo, Chaebeom; Park, Hyun-Cheol; Lee, Kijoon; Song, Cheol

    2016-01-01

    Determining the survival rate of avian embryos during incubation is essential for cost-saving in the poultry industry. A multi-channel diffuse speckle contrast analysis (DSCA) system, comprising four optical fiber channels, is proposed to achieve noninvasive in vivo measurements of deep tissue flow. The system was able to monitor chick embryo vital signs over the entire incubation period. Moreover, it proved useful in distinguishing between chick embryos in healthy and weakened conditions. PMID:26819820

  9. Avian embryo monitoring during incubation using multi-channel diffuse speckle contrast analysis

    PubMed Central

    Yeo, Chaebeom; Park, Hyun-cheol; Lee, Kijoon; Song, Cheol

    2015-01-01

    Determining the survival rate of avian embryos during incubation is essential for cost-saving in the poultry industry. A multi-channel diffuse speckle contrast analysis (DSCA) system, comprising four optical fiber channels, is proposed to achieve noninvasive in vivo measurements of deep tissue flow. The system was able to monitor chick embryo vital signs over the entire incubation period. Moreover, it proved useful in distinguishing between chick embryos in healthy and weakened conditions. PMID:26819820

  10. Teen Chick Lit

    ERIC Educational Resources Information Center

    Meloni, Christine

    2006-01-01

    For young teen girls, reading has become hot again. With their appealing covers, witty heroines and humorous plots, teen chick lit books are bringing girls out of the malls and into local libraries and bookstores in search of the next must-have title. These fun books are about boys, friendship, family, fitting in, and growing up. What makes the…

  11. Yolk hormones influence in ovo chemosensory learning, growth, and feeding behavior in domestic chicks.

    PubMed

    Bertin, Aline; Meurisse, Maryse; Arnould, Cécile; Leterrier, Christine; Constantin, Paul; Cornilleau, Fabien; Vaudin, Pascal; Burlot, Thierry; Delaveau, Joel; Rat, Christophe; Calandreau, Ludovic

    2016-03-01

    In this study, we assessed whether prenatal exposure to elevated yolk steroid hormones can influence in ovo chemosensory learning and the behavior of domestic chicks. We simulated a maternal environmental challenge by experimentally enhancing yolk progesterone, testosterone, and estradiol concentrations in hen eggs prior to incubation. The embryos from these hormones-treated eggs (HO) as well as sham embryos (O) that had received the vehicle-only were exposed to the odor of fish oil (menhaden) between embryonic Days 11 and 20. An additional group of control embryos (C) was not exposed to the odor. All chicks were tested following hatching for their feeding preferences between foods that were or were not odorized with the menhaden odor. In the 3-min choice tests, the behavior of O chicks differed significantly according to the type of food whereas C and HO chicks showed no preference between odorized and non-odorized food. Our result suggests weaker response in HO chicks. In addition, HO chicks showed impaired growth and reduced intake of an unfamiliar food on the 24-h time scale compared to controls. Our data suggest that embryonic exposure to increased yolk hormone levels can alter growth, chemosensory learning, and the development of feeding behaviors.

  12. Yolk hormones influence in ovo chemosensory learning, growth, and feeding behavior in domestic chicks.

    PubMed

    Bertin, Aline; Meurisse, Maryse; Arnould, Cécile; Leterrier, Christine; Constantin, Paul; Cornilleau, Fabien; Vaudin, Pascal; Burlot, Thierry; Delaveau, Joel; Rat, Christophe; Calandreau, Ludovic

    2016-03-01

    In this study, we assessed whether prenatal exposure to elevated yolk steroid hormones can influence in ovo chemosensory learning and the behavior of domestic chicks. We simulated a maternal environmental challenge by experimentally enhancing yolk progesterone, testosterone, and estradiol concentrations in hen eggs prior to incubation. The embryos from these hormones-treated eggs (HO) as well as sham embryos (O) that had received the vehicle-only were exposed to the odor of fish oil (menhaden) between embryonic Days 11 and 20. An additional group of control embryos (C) was not exposed to the odor. All chicks were tested following hatching for their feeding preferences between foods that were or were not odorized with the menhaden odor. In the 3-min choice tests, the behavior of O chicks differed significantly according to the type of food whereas C and HO chicks showed no preference between odorized and non-odorized food. Our result suggests weaker response in HO chicks. In addition, HO chicks showed impaired growth and reduced intake of an unfamiliar food on the 24-h time scale compared to controls. Our data suggest that embryonic exposure to increased yolk hormone levels can alter growth, chemosensory learning, and the development of feeding behaviors. PMID:26419601

  13. Chick tooth induction revisited.

    PubMed

    Cai, Jinglei; Cho, Sung-Won; Ishiyama, Mikio; Mikami, Masato; Hosoya, Akihiro; Kozawa, Yukishige; Ohshima, Hayato; Jung, Han-Sung

    2009-07-15

    Teeth have been missing from Aves for almost 100 million years. However, it is believed that the avian oral epithelium retains the molecular signaling required to induce odontogenesis, and this has been widely examined using heterospecific recombinations with mouse dental mesenchyme. It has also been argued that teeth can form from the avian oral epithelium owing to contamination of the mouse mesenchyme with mouse dental epithelial cells. To investigate the possibility of tooth formation from chick oral epithelium and the characteristics of possible chick enamel, we applied LacZ transgenic mice during heterospecific recombination and examined the further tooth formation. Transmission electron microscopy was used to identify the two tissues during development after heterospecific recombination. No mixing was detected between chick oral epithelium and mouse dental mesenchyme after 2 days, and secretory ameloblasts with Tomes' processes were observed after 1 week. Teeth were formed after 3 weeks with a single cusp pattern, possibly determined by epithelial factors, which is similar to that of the avian tooth in the late Jurassic period. These recombinant teeth were smaller than mouse molars, whereas perfect structures of both ameloblasts and enamel showed histological characteristics similar to those of mice. Together these observations consistent with previous report that odontogenesis is initially directed by species-specific mesenchymal signals interplaying with common epithelial signals. PMID:19226602

  14. Chick tooth induction revisited.

    PubMed

    Cai, Jinglei; Cho, Sung-Won; Ishiyama, Mikio; Mikami, Masato; Hosoya, Akihiro; Kozawa, Yukishige; Ohshima, Hayato; Jung, Han-Sung

    2009-07-15

    Teeth have been missing from Aves for almost 100 million years. However, it is believed that the avian oral epithelium retains the molecular signaling required to induce odontogenesis, and this has been widely examined using heterospecific recombinations with mouse dental mesenchyme. It has also been argued that teeth can form from the avian oral epithelium owing to contamination of the mouse mesenchyme with mouse dental epithelial cells. To investigate the possibility of tooth formation from chick oral epithelium and the characteristics of possible chick enamel, we applied LacZ transgenic mice during heterospecific recombination and examined the further tooth formation. Transmission electron microscopy was used to identify the two tissues during development after heterospecific recombination. No mixing was detected between chick oral epithelium and mouse dental mesenchyme after 2 days, and secretory ameloblasts with Tomes' processes were observed after 1 week. Teeth were formed after 3 weeks with a single cusp pattern, possibly determined by epithelial factors, which is similar to that of the avian tooth in the late Jurassic period. These recombinant teeth were smaller than mouse molars, whereas perfect structures of both ameloblasts and enamel showed histological characteristics similar to those of mice. Together these observations consistent with previous report that odontogenesis is initially directed by species-specific mesenchymal signals interplaying with common epithelial signals.

  15. Gastrointestinal obstruction in penguin chicks.

    PubMed

    Perpiñán, David; Curro, Thomas G

    2009-12-01

    A 7-day-old gentoo penguin (Pygoscelis papua) was found dead and postmortem examination revealed impaction of the ventriculus with feathers. A review of mortality in gentoo penguin chicks from 1997 to 2007 at that institution revealed another case of feather impaction of the ventriculus in a 4-week-old chick, a sibling of the previous chick. A third case of gastrointestinal impaction occurred in a 24-day-old king penguin (Aptenodytes patagonicus) with omphallitis and enteritis. In this chick, a fibrin mat produced a complete obstruction of the intestine at the level of Meckel's diverticulum. PMID:20235460

  16. Limb regeneration.

    PubMed

    Simon, András; Tanaka, Elly M

    2013-01-01

    Limb regeneration is observed in certain members of the animal phyla. Some animals keep this ability during their entire life while others lose it at some time during development. How do animals regenerate limbs? Is it possible to find unifying, conserved mechanisms of limb regeneration or have different species evolved distinct means of replacing a lost limb? How is limb regeneration similar or different to limb development? Studies on many organisms, including echinoderms, arthropods, and chordates have provided significant knowledge about limb regeneration. In this focus article, we concentrate on tetrapod limb regeneration as studied in three model amphibians: newts, axolotls, and frogs. We review recent progress on tissue interactions during limb regeneration, and place those findings into an evolutionary context. PMID:24009038

  17. Recent advances in the study of limb development: the emergence and function of the apical ectodermal ridge.

    PubMed

    Rodriguez-Leon, Joaquin; Tomas, Ana Raquel; Johnson, Austin; Kawakami, Yasuhiko

    2013-01-01

    Vertebrate extremities develop from limb buds, which emerge as paired protrusions in the lateral plate mesoderm. Forelimb buds are located anteriorly and hindlimb buds are positioned posteriorly. The morphogenesis of the limb requires coordinated actions of several organizing centers, among which the apical ectodermal ridge (AER) plays crucial roles in limb development. Recent studies have shown how the life of the AER (induction, maturation, maintenance and regression) is regulated. This regulation includes cell type- and process- specific roles of previously identified molecules, such as fibroblast growth factors (FGFs), Wnts and bone morphogenetic proteins (BMPs). The studies have also revealed several new players, such as Arid3b, R-Spondin 2 and Flrt3. These advances have enhanced the understanding of how the AER is regulated from its emergence to its regression. Progress has also been made in understanding AER function in relation to processes critical for limb development: proximal-distal patterning, anterior-posterior patterning, chondrogenesis and apoptosis. By focusing on two major model systems, chick and mouse embryos, we will review recent advances in combination with relevant previous studies in the development and function of the AER.

  18. Pbx Homeodomain Proteins: TALEnted regulators of Limb Patterning and Outgrowth

    PubMed Central

    Capellini, Terence D.; Zappavigna, Vincenzo; Selleri, Licia

    2011-01-01

    Limb development has long provided an excellent model for understanding the genetic principles driving embryogenesis. Studies utilizing chick and mouse have led to new insights into limb patterning and morphogenesis. Recent research has centered on the regulatory networks underlying limb development. Here, we discuss the hierarchical, overlapping, and iterative roles of Pbx family members in appendicular development that have emerged from genetic analyses in the mouse. Pbx genes are essential in determining limb bud positioning, early bud formation, limb axes establishment and coordination, and patterning and morphogenesis of most elements of the limb and girdle. Pbx proteins directly regulate critical effectors of limb and girdle development, including morphogen-encoding genes like Shh in limb posterior mesoderm, and transcription factor-encoding genes like Alx1 in pre-scapular domains. Interestingly, at least in limb buds, Pbx appear to act not only as Hox cofactors, but also in the upstream control of 5' HoxA/D gene expression. PMID:21416555

  19. Otic Lesions and Congenital Hypothyroidism in the Developing Chick*

    PubMed Central

    Bargman, Gerald J.; Gardner, Lytt I.

    1967-01-01

    In an effort to elucidate the relation, if any, between thyroid abnormality and congenital deafness in Pendred's syndrome, an experiment was designed to study the effects of hypothyroidism on middle and inner ear hearing structures, including the auditory nerve and its central projection, in developing chick embryos. Propylthiouracil (PTU), 2 mg, was injected into the albumin of fertile chick eggs on the 10th incubation day. Single doses of L-thyroxine (range 1-100μg) were inoculated in a similar manner, either alone or with PTU. Control inocula included sterile saline or water. After hatching, each chick was examined for obvious malformations. The thyroid glands, middle and inner ear mechanisms, auditory nerve, and brainstem were studied grossly and with different histologic staining techniques. When compared to controls, chicks exposed to PTU on their 10th incubation day exhibited: increased mortality, delayed hatching, reduced size, incomplete yolk sac absorption, and death within 5 days unless exogenous thyroid hormone was provided in the first 24-48 hr after hatching. Specific, consistent, morphologic alterations were observed in their thyroid glands as well as in the sensory hair cells of the acoustic papilla and cells of the spiral ganglion of the cochlea. Our data also indicate that if 50-75 μg of L-thyroxine is given simultaneously with (or as long as 120 hr after) the PTU injection on the 10th incubation day, one cannot detect the gross defects, marked thyroid lesions, or abnormal histology in cells of the cochlea and its ganglion. A relationship between embryonic thyroid gland function and the hearing mechanism of the chick embryo is suggested. Images PMID:6070327

  20. Artificial Limbs

    MedlinePlus

    ... you are missing an arm or leg, an artificial limb can sometimes replace it. The device, which is ... activities such as walking, eating, or dressing. Some artificial limbs let you function nearly as well as before.

  1. Limb Loss

    MedlinePlus

    ... accidents and military combat Cancer Birth defects Some amputees have phantom pain, which is the feeling of ... problems, if you wear an artificial limb. Many amputees use an artificial limb. Learning how to use ...

  2. Characterization of cDNAs encoding the chick retinoic acid receptor gamma 2 and preferential distribution of retinoic acid receptor gamma transcripts during chick skin development.

    PubMed

    Michaille, J J; Blanchet, S; Kanzler, B; Garnier, J M; Dhouailly, D

    1994-12-01

    Retinoic acid receptors alpha, beta and gamma (RAR alpha, beta and gamma) are ligand-inductible transcriptional activators which belong to the steroid/thyroid hormone receptor superfamily. At least two major isoforms (1 and 2) of each RAR arise by differential use of two promoters and alternative splicing. In mouse, the three RAR genes are expressed in stage- and tissue-specific patterns during embryonic development. In order to understand the role of the different RARs in chick, RAR gamma 2 cDNAs were isolated from an 8.5-day (stage 35 of Hamburger and Hamilton) chick embryo skin library. The deduced chick RAR gamma 2 amino acid sequence displays uncommon features such as 21 specific amino acid replacements, 12 of them being clustered in the amino-terminal region (domains A2 and B), and a truncated acidic carboxy-terminal region (F domain). However, the pattern of RAR gamma expression in chick embryo resembles that reported in mouse, particularly in skin where RAR gamma expression occurs in both the dermal and epidermal layers at the beginning of feather formation, and is subsequently restricted to the differentiating epidermal cells. Northern blot analysis suggests that different RAR gamma isoforms could be successively required during chick development.

  3. Artificially Increased Yolk Hormone Levels and Neophobia in Domestic Chicks.

    PubMed

    Bertin, Aline; Arnould, Cécile; Moussu, Chantal; Meurisse, Maryse; Constantin, Paul; Leterrier, Christine; Calandreau, Ludovic

    2015-01-01

    In birds there is compelling evidence that the development and expression of behavior is affected by maternal factors, particularly via variation in yolk hormone concentrations of maternal origin. In the present study we tested whether variation in yolk hormone levels lead to variation in the expression of neophobia in young domestic chicks. Understanding how the prenatal environment could predispose chicks to express fear-related behaviors is essential in order to propose preventive actions and improve animal welfare. We simulated the consequences of a maternal stress by experimentally enhancing yolk progesterone, testosterone and estradiol concentrations in hen eggs prior to incubation. The chicks from these hormone-treated eggs (H) and from sham embryos (C) that received the vehicle-only were exposed to novel food, novel object and novel environment tests. H chicks approached a novel object significantly faster and were significantly more active in a novel environment than controls, suggesting less fearfulness. Conversely, no effect of the treatment was found in food neophobia tests. Our study highlights a developmental influence of yolk hormones on a specific aspect of neophobia. The results suggest that increased yolk hormone levels modulate specifically the probability of exploring novel environments or novel objects in the environment. PMID:26633522

  4. Artificially Increased Yolk Hormone Levels and Neophobia in Domestic Chicks

    PubMed Central

    Bertin, Aline; Arnould, Cécile; Moussu, Chantal; Meurisse, Maryse; Constantin, Paul; Leterrier, Christine; Calandreau, Ludovic

    2015-01-01

    In birds there is compelling evidence that the development and expression of behavior is affected by maternal factors, particularly via variation in yolk hormone concentrations of maternal origin. In the present study we tested whether variation in yolk hormone levels lead to variation in the expression of neophobia in young domestic chicks. Understanding how the prenatal environment could predispose chicks to express fear-related behaviors is essential in order to propose preventive actions and improve animal welfare. We simulated the consequences of a maternal stress by experimentally enhancing yolk progesterone, testosterone and estradiol concentrations in hen eggs prior to incubation. The chicks from these hormone-treated eggs (H) and from sham embryos (C) that received the vehicle-only were exposed to novel food, novel object and novel environment tests. H chicks approached a novel object significantly faster and were significantly more active in a novel environment than controls, suggesting less fearfulness. Conversely, no effect of the treatment was found in food neophobia tests. Our study highlights a developmental influence of yolk hormones on a specific aspect of neophobia. The results suggest that increased yolk hormone levels modulate specifically the probability of exploring novel environments or novel objects in the environment. PMID:26633522

  5. Artificially Increased Yolk Hormone Levels and Neophobia in Domestic Chicks.

    PubMed

    Bertin, Aline; Arnould, Cécile; Moussu, Chantal; Meurisse, Maryse; Constantin, Paul; Leterrier, Christine; Calandreau, Ludovic

    2015-11-30

    In birds there is compelling evidence that the development and expression of behavior is affected by maternal factors, particularly via variation in yolk hormone concentrations of maternal origin. In the present study we tested whether variation in yolk hormone levels lead to variation in the expression of neophobia in young domestic chicks. Understanding how the prenatal environment could predispose chicks to express fear-related behaviors is essential in order to propose preventive actions and improve animal welfare. We simulated the consequences of a maternal stress by experimentally enhancing yolk progesterone, testosterone and estradiol concentrations in hen eggs prior to incubation. The chicks from these hormone-treated eggs (H) and from sham embryos (C) that received the vehicle-only were exposed to novel food, novel object and novel environment tests. H chicks approached a novel object significantly faster and were significantly more active in a novel environment than controls, suggesting less fearfulness. Conversely, no effect of the treatment was found in food neophobia tests. Our study highlights a developmental influence of yolk hormones on a specific aspect of neophobia. The results suggest that increased yolk hormone levels modulate specifically the probability of exploring novel environments or novel objects in the environment.

  6. Chicks like consonant music.

    PubMed

    Chiandetti, Cinzia; Vallortigara, Giorgio

    2011-10-01

    The question of whether preference for consonance is rooted in acoustic properties important to the auditory system or is acquired through enculturation has not yet been resolved. Two-month-old infants prefer consonant over dissonant intervals, but it is possible that this preference is rapidly acquired through exposure to music soon after birth or in utero. Controlled-rearing studies with animals can help shed light on this question because such studies allow researchers to distinguish between biological predispositions and learned preferences. In the research reported here, we found that newly hatched domestic chicks show a spontaneous preference for a visual imprinting object associated with consonant sound intervals over an identical object associated with dissonant sound intervals. We propose that preference for harmonic relationships between frequency components may be related to the prominence of harmonic spectra in biological sounds in natural environments. PMID:21934134

  7. Brain asymmetry modulates perception of biological motion in newborn chicks (Gallus gallus).

    PubMed

    Rugani, Rosa; Rosa Salva, Orsola; Regolin, Lucia; Vallortigara, Giorgio

    2015-09-01

    Few light-points on the joints of a moving animal give the impression of biological motion (BM). Day-old chicks prefer BM to non-BM, suggesting a conserved predisposition to attend to moving animals. In humans and other mammals a network of regions, primarily in the right hemisphere, provides the neural substrate for BM perception. However, this has not been investigated in avians. In birds the information from each eye is mainly feeding to the contralateral hemisphere. To study brain asymmetry, we recorded the eye spontaneously used by chicks to inspect a BM stimulus. We also investigated the effect of lateralization following light exposure of the embryos. In Experiment 1, highly lateralized chicks aligned with the apparent direction of motion only when they were exposed to a BM-stimulus moving rightward first, monitoring it with the left-eye-system. In Experiment 2 weakly lateralized chicks did not show any behavioral asymmetry. Moreover, they counter aligned with the apparent direction of motion. Brain lateralization affects chicks behavior while processing and approaching a BM stimulus. Highly lateralized chicks aligned their body with the apparent direction of the BM, a behavior akin to a following response, monitoring the stimulus preferentially with their left eye. This suggests a right hemisphere dominance in BM processing. Weakly lateralized chicks counter-aligned with the apparent direction of the BM, facing it during interaction, and monitored it equally with both eyes. Environmental factors (light stimulation) seem to affect the development of lateralization, and consequently social behavior. PMID:25930217

  8. Brain asymmetry modulates perception of biological motion in newborn chicks (Gallus gallus).

    PubMed

    Rugani, Rosa; Rosa Salva, Orsola; Regolin, Lucia; Vallortigara, Giorgio

    2015-09-01

    Few light-points on the joints of a moving animal give the impression of biological motion (BM). Day-old chicks prefer BM to non-BM, suggesting a conserved predisposition to attend to moving animals. In humans and other mammals a network of regions, primarily in the right hemisphere, provides the neural substrate for BM perception. However, this has not been investigated in avians. In birds the information from each eye is mainly feeding to the contralateral hemisphere. To study brain asymmetry, we recorded the eye spontaneously used by chicks to inspect a BM stimulus. We also investigated the effect of lateralization following light exposure of the embryos. In Experiment 1, highly lateralized chicks aligned with the apparent direction of motion only when they were exposed to a BM-stimulus moving rightward first, monitoring it with the left-eye-system. In Experiment 2 weakly lateralized chicks did not show any behavioral asymmetry. Moreover, they counter aligned with the apparent direction of motion. Brain lateralization affects chicks behavior while processing and approaching a BM stimulus. Highly lateralized chicks aligned their body with the apparent direction of the BM, a behavior akin to a following response, monitoring the stimulus preferentially with their left eye. This suggests a right hemisphere dominance in BM processing. Weakly lateralized chicks counter-aligned with the apparent direction of the BM, facing it during interaction, and monitored it equally with both eyes. Environmental factors (light stimulation) seem to affect the development of lateralization, and consequently social behavior.

  9. Proteome analysis of chick embryonic cerebrospinal fluid.

    PubMed

    Parada, Carolina; Gato, Angel; Aparicio, Mariano; Bueno, David

    2006-01-01

    During early stages of embryo development, the brain cavity is filled with embryonic cerebrospinal fluid (E-CSF), a complex fluid containing different protein fractions that contributes to the regulation of the survival, proliferation and neurogenesis of the neuroectodermal stem cells. Using 2-DE, protein sequencing and database searches, we identified and analyzed the proteome of the E-CSF from chick embryos (Gallus gallus). We identified 26 different gene products, including proteins related to the extracellular matrix, proteins associated with the regulation of osmotic pressure and metal transport, proteins related to cell survival, MAP kinase activators, proteins involved in the transport of retinol and vitamin D, antioxidant and antimicrobial proteins, intracellular proteins and some unknown proteins. Most of these gene products are involved in the regulation of developmental processes during embryogenesis in systems other than E-CSF. Interestingly, 14 of them are also present in adult human CSF proteome, and it has been reported that they are altered in the CSF of patients suffering neurodegenerative diseases and/or neurological disorders. Understanding these molecules and the mechanisms they control during embryonic neurogenesis is a key contribution to the general understanding of CNS development, and may also contribute to greater knowledge of these human diseases. PMID:16287170

  10. Transcription Factor Erg Variants and Functional Diversification of Chondrocytes during Limb Long Bone Development

    PubMed Central

    Iwamoto, Masahiro; Higuchi, Yoshinobu; Koyama, Eiki; Enomoto-Iwamoto, Motomi; Kurisu, Kojiro; Yeh, Helena; Abrams, William R.; Rosenbloom, Joel; Pacifici, Maurizio

    2000-01-01

    During limb development, chondrocytes located at the epiphyseal tip of long bone models give rise to articular tissue, whereas the more numerous chondrocytes in the shaft undergo maturation, hypertrophy, and mineralization and are replaced by bone cells. It is not understood how chondrocytes follow these alternative pathways to distinct fates and functions. In this study we describe the cloning of C-1-1, a novel variant of the ets transcription factor ch-ERG. C-1-1 lacks a short 27–amino acid segment located ∼80 amino acids upstream of the ets DNA binding domain. We found that in chick embryo long bone anlagen, C-1-1 expression characterizes developing articular chondrocytes, whereas ch-ERG expression is particularly prominent in prehypertrophic chondrocytes in the growth plate. To analyze the function of C-1-1 and ch-ERG, viral vectors were used to constitutively express each factor in developing chick leg buds and cultured chondrocytes. We found that virally driven expression of C-1-1 maintained chondrocytes in a stable and immature phenotype, blocked their maturation into hypertrophic cells, and prevented the replacement of cartilage with bone. It also induced synthesis of tenascin-C, an extracellular matrix protein that is a unique product of developing articular chondrocytes. In contrast, virally driven expression of ch-ERG significantly stimulated chondrocyte maturation in culture, as indicated by increases in alkaline phosphatase activity and deposition of a mineralized matrix; however, it had modest effects in vivo. The data show that C-1-1 and ch-ERG have diverse biological properties and distinct expression patterns during skeletogenesis, and are part of molecular mechanisms by which limb chondrocytes follow alternative developmental pathways. C-1-1 is the first transcription factor identified to date that appears to be instrumental in the genesis and function of epiphyseal articular chondrocytes. PMID:10893254

  11. From the Cover: Exposing Imidacloprid Interferes With Neurogenesis Through Impacting on Chick Neural Tube Cell Survival.

    PubMed

    Liu, Meng; Wang, Guang; Zhang, Shi-Yao; Zhong, Shan; Qi, Guo-Long; Wang, Chao-Jie; Chuai, Manli; Lee, Kenneth Ka Ho; Lu, Da-Xiang; Yang, Xuesong

    2016-09-01

    As a neonicotinoid pesticide, imidacloprid is widely used to control insects in agriculture and fleas on domestic animals. However, it is not known whether imidacloprid exposure negatively affects neurogenesis during embryonic development. In this study, using a chick embryo model, we investigated the effects of imidacloprid exposure on neurogenesis at the earliest stage and during late-stage embryo development. Exposing HH0 chick embryos to imidacloprid in EC culture caused neural tube defects (NTDs) and neuronal differentiation dysplasia as determined by NF/Tuj1 labeling. Furthermore, we found that F-actin accumulation on the apical side of the neural tube was suppressed by exposure to imidacloprid, and the expression of BMP4 and Shh on the dorsal and ventral sides of the neural tubes, respectively, were also reduced, which in turn affects the dorsolateral hinge points during bending of the neural plate. In addition, exposure to imidacloprid reduced cell proliferation and increased cell apoptosis, as determined by pHIS3 labeling and TUNEL staining, respectively, also contributing to the malformation. We obtained similar results in late-stage embryos exposed to imidacloprid. Finally, a bioinformatics analysis was employed to determine which genes identified in this study were involved in NTDs. The experimental evidence and bioinformatics analysis suggested that imidacloprid exposure during chick embryo development could increase the risk of NTDs and neural dysplasia.

  12. From the Cover: Exposing Imidacloprid Interferes With Neurogenesis Through Impacting on Chick Neural Tube Cell Survival.

    PubMed

    Liu, Meng; Wang, Guang; Zhang, Shi-Yao; Zhong, Shan; Qi, Guo-Long; Wang, Chao-Jie; Chuai, Manli; Lee, Kenneth Ka Ho; Lu, Da-Xiang; Yang, Xuesong

    2016-09-01

    As a neonicotinoid pesticide, imidacloprid is widely used to control insects in agriculture and fleas on domestic animals. However, it is not known whether imidacloprid exposure negatively affects neurogenesis during embryonic development. In this study, using a chick embryo model, we investigated the effects of imidacloprid exposure on neurogenesis at the earliest stage and during late-stage embryo development. Exposing HH0 chick embryos to imidacloprid in EC culture caused neural tube defects (NTDs) and neuronal differentiation dysplasia as determined by NF/Tuj1 labeling. Furthermore, we found that F-actin accumulation on the apical side of the neural tube was suppressed by exposure to imidacloprid, and the expression of BMP4 and Shh on the dorsal and ventral sides of the neural tubes, respectively, were also reduced, which in turn affects the dorsolateral hinge points during bending of the neural plate. In addition, exposure to imidacloprid reduced cell proliferation and increased cell apoptosis, as determined by pHIS3 labeling and TUNEL staining, respectively, also contributing to the malformation. We obtained similar results in late-stage embryos exposed to imidacloprid. Finally, a bioinformatics analysis was employed to determine which genes identified in this study were involved in NTDs. The experimental evidence and bioinformatics analysis suggested that imidacloprid exposure during chick embryo development could increase the risk of NTDs and neural dysplasia. PMID:27444676

  13. Medical Management of Hypovitaminosis D With Cholecalciferol and Elastic Therapeutic Taping in Red-legged Seriema (Cariama cristata) Chicks.

    PubMed

    Kozel, Caitlin A; Kinney, Matthew E; Hanley, Christopher S; Padilla, Luis R

    2016-03-01

    Three hand-reared, 50-53 day-old, red-legged seriema (Cariama cristata) chicks were evaluated for acute lameness and reluctance to ambulate. Two of the 3 chicks presented with angular limb deformities of the proximal tarsometatarsi and external rotation of the legs. Radiographs demonstrated decreased opacity of the long bone of the legs, with poorly delineated cortices and deviation of the proximal tarsometarsi. Serum concentrations of 25-hydroxycholecalciferol revealed all 3 chicks were deficient in vitamin D(3) at presentation. The chicks were administered injectable vitamin D(3) (cholecalciferol), oral vitamin D(3), and an ultraviolet B (UV-B) light was placed in their enclosure. Elastic, therapeutic taping was used to correct angular limb deformities present in 2 of the 3 chicks. Taping was continued until the angular limb deformities were corrected and lameness resolved. Hypovitaminosis D is a common cause of metabolic bone disease in captive avian species. Cholecalciferol administration, UV-B light supplementation, and elastic, therapeutic taping were effective treatments for osteodystrophy and secondary angular limb deformities due to hypovitaminosis D. This multifaceted treatment may be useful in other long-legged juvenile birds with similar clinical signs. PMID:27088745

  14. The chick somitogenesis oscillator is arrested before all paraxial mesoderm is segmented into somites

    PubMed Central

    2010-01-01

    Background Somitogenesis is the earliest sign of segmentation in the developing vertebrate embryo. This process starts very early, soon after gastrulation has initiated and proceeds in an anterior-to-posterior direction during body axis elongation. It is widely accepted that somitogenesis is controlled by a molecular oscillator with the same periodicity as somite formation. This periodic mechanism is repeated a specific number of times until the embryo acquires a defined specie-specific final number of somites at the end of the process of axis elongation. This final number of somites varies widely between vertebrate species. How termination of the process of somitogenesis is determined is still unknown. Results Here we show that during development there is an imbalance between the speed of somite formation and growth of the presomitic mesoderm (PSM)/tail bud. This decrease in the PSM size of the chick embryo is not due to an acceleration of the speed of somite formation because it remains constant until the last stages of somitogenesis, when it slows down. When the chick embryo reaches its final number of somites at stage HH 24-25 there is still some remaining unsegmented PSM in which expression of components of the somitogenesis oscillator is no longer dynamic. Finally, we identify a change in expression of retinoic acid regulating factors in the tail bud at late stages of somitogenesis, such that in the chick embryo there is a pronounced onset of Raldh2 expression while in the mouse embryo the expression of the RA inhibitor Cyp26A1 is downregulated. Conclusions Our results show that the chick somitogenesis oscillator is arrested before all paraxial mesoderm is segmented into somites. In addition, endogenous retinoic acid is probably also involved in the termination of the process of segmentation, and in tail growth in general. PMID:20184730

  15. Development of otoconia in the embryonic chick (Gallus domesticus)

    NASA Technical Reports Server (NTRS)

    Fermin, C. D.; Igarashi, M.

    1985-01-01

    In the chick (Gallus domesticus) embryo, otoconium formation started first over the macula sacculi around the 4th day of incubation, and a day later over the macula utriculi. It was determined that each otoconium formed as a result of the segmentation of the immature otolithic membrane, and that the calcium responsible for otoconium calcification was incorporated into the organic matrix of each otoconium in the form of small electron-dense granules (20-150 nm in. diameter). The presence of calcium in these granules was confirmed by histochemical staining with osmic-potassium pyroantimonate, by EDTA chelation, and by X-ray micronanalysis under the electron microscope.

  16. High-resolution MRI analysis of breast cancer xenograft on the chick chorioallantoic membrane.

    PubMed

    Zuo, Zhi; Syrovets, Tatiana; Genze, Felicitas; Abaei, Alireza; Ma, Genshan; Simmet, Thomas; Rasche, Volker

    2015-04-01

    The chick chorioallantoic membrane (CAM) model has been successfully used to study angiogenesis, cancer progression and its pharmacological treatment, tumor pharmacokinetics, and properties of novel nanomaterials. MRI is an attractive technique for non-invasive and longitudinal monitoring of physiological processes and tumor growth. This study proposes an age-adapted cooling regime for immobilization of the chick embryo, enabling high-resolution MRI of the embryo and the CAM tumor xenograft. 64 chick embryos were enrolled in this study. The novel immobilization and imaging protocol was optimized in 29 embryos. From d7 to d18 immobilization of the embryo up to 90 min was achieved by cooling at 4 °C pre-imaging, with cooling times adapted to age. Its application to tumor growth monitoring was evaluated in 15 embryos after xenotransplantation of human MDA-MB-231 breast cancer cells on CAM. Tumor volumes were monitored from d4 to d9 after grafting (d11 to d16 after incubation) applying a T2 -weighted multislice RARE sequence. At d9 after grafting, the tumors were collected and compared with the MRI-derived data by histology and weight measurements. Additional imaging methods comprising DWI, T2 mapping, and the bio-distribution of contrast agents were tested at d9 after grafting in 20 further embryos. With the adaptive cooling regime, motion artifacts could be completely avoided for up to 90 min scan time, enabling high-resolution in ovo imaging. Excellent anatomical details could be obtained in the embryo and tumors. Tumor volumes could be quantified over time. The results prove the feasibility of high-resolution MRI for longitudinal tumor and organ growth monitoring. The suggested method is promising for future applications such as testing tailored and/or targeted treatment strategies, longitudinal monitoring of tumor development, analysis of therapeutic efficacies of drugs, or assessment of tumor pharmacokinetics. The method provides an alternative to animal

  17. The effects of embryonic treatments with gonadal hormones on sexually dimorphic behavior of chicks.

    PubMed

    Sayag, N; Robinzon, B; Snapir, N; Arnon, E; Grimm, V E

    1991-06-01

    In order to study the role of sex steroids in the differentiation of chick behavior, two groups of experiments were carried out. The first part of the study documented sexual dimorphisms in three behavioral measures in chicks: open-field activity, flocking response, and masculine sexual behavior activated by testosterone (crowing, waltzing, and mating attempts). In the second part, possible organizing influences on these sexually dimorphic behaviors were examined. Male and female embryos were injected with estradiol benzoate (EB) or testosterone propionate (TP). Treatment of males with EB or TP demasculinized all three behaviors. None of the steroid treatments had any effect on the behavior of the females. Plasma testosterone levels of the chicks were not affected by any of these treatments, either before or after testosterone activation. Comb weight was reduced by treatment of male embryos with EB and increased by TP in female embryos, which suggests different mechanism for the development of somatic and behavioral characteristics. The results suggest that exogenous T or E given embryonically can exert similar effects on both sexual behavior and nonreproductive activity of chicks. PMID:2066077

  18. Prenatal imaging of distal limb abnormalities using OCT in mice

    NASA Astrophysics Data System (ADS)

    Larina, Irina V.; Syed, Saba H.; Dickinson, Mary E.; Overbeek, Paul; Larin, Kirill V.

    2012-01-01

    Congenital abnormalities of the limbs are common birth defects. These include missing or extra fingers or toes, abnormal limb length, and abnormalities in patterning of bones, cartilage or muscles. Optical Coherence Tomography (OCT) is a 3-D imaging modality, which can produce high-resolution (~8 μm) images of developing embryos with an imaging depth of a few millimeters. Here we demonstrate the capability of OCT to perform 3D imaging of limb development in normal embryos and a mouse model with congenital abnormalities. Our results suggest that OCT is a promising tool to analyze embryonic limb development in mammalian models of congenital defects.

  19. Somitomeres: mesodermal segments of vertebrate embryos.

    PubMed

    Jacobson, A G

    1988-01-01

    Well before the somites form, the paraxial mesoderm of vertebrate embryos is segmented into somitomeres. When newly formed, somitomeres are patterned arrays of mesenchymal cells, arranged into squat, bilaminar discs. The dorsal and ventral faces of these discs are composed of concentric rings of cells. Somitomeres are formed along the length of the embryo during gastrulation, and in the segmental plate and tail bud at later stages. They form in strict cranial to caudal order. They appear in bilateral pairs, just lateral to Hensen's node in the chick embryo. When the nervous system begins to form, the brain parts and neuromeres are in a consistent relationship to the somitomeres. Somitomeres first appear in the head, and the cranial somitomeres do not become somites, but disperse to contribute to the head the same cell types contributed by somites in the trunk region. In the trunk and tail, somitomeres gradually condense and epithelialize to become somites. Models of vertebrate segmentation must now take into account the early presence of these new morphological units, the somitomeres. Somitomeres were discovered in the head of the chick embryo (Meier, 1979), with the use of stereo scanning electron microscopy. The old question of whether the heads of the craniates are segmented is now settled, at least for the paraxial mesoderm. Somitomeres have now been identified in the embryos of a chick, quail, mouse, snapping turtle, newt, anuran (Xenopus) and a teleost (the medaka). In all forms studied, the first pair of somitomeres abut the prosencephalon, but caudal to that, for each tandem pair of somitomeres in the amniote and teleost, there is but one somitomere in the amphibia. The mesodermal segments of the shark embryo are arranged like those of the amphibia.

  20. Amplification of moderately repetitive DNA sequences during chick cartilage differentiation.

    PubMed Central

    Strom, C M; Dorfman, A

    1976-01-01

    A 5-bromo-2'-[3H]deoxyuridine (BrdUrd) probe was isolated to analyze DNAs obtained from various chick tissues and cell types. [3H]BrdUrd-substituted DNA, prepared from limb bud cultures, was sheared and freed from palindromic DNA. Nonradioactive DNA was prepared from embryonic liver, undifferentiated limb bud mesenchyme, sternal cartilage, differentiated limb bud cultures, and BrdUrd-blocked cultures, and was sheared. These DNAs were used in 100-fold excess to drive the reassociation of the [3H]-BrdUrd-DNA probe. Purified mature cartilage DNAs of embryonic sternae or differentiated limb bud cultures drove the reassociation of the probe approximately two times faster than did DNA from liver, undifferentiated limb bud, or BrdUrd-blocked cells. These data indicate that cartilage DNA contains a greater number of sequences complementary to the BrdUrd probe than do DNAs of noncartilage or undifferentiated precartilage cells. Calculations determined an average substitution of 10% of thymidine residues by BrdUrd in purified probe, whereas CsCl density gradients of unsheared probe revealed radioactive peaks of greater than 20% substitution. The BrdUrd appears to be clustered in the genome. PMID:1068455

  1. Effects of incubational humidity and hen age on embryo composition in broiler hatching eggs from young breeders.

    PubMed

    Peebles, E D; Burnham, M R; Gardner, C W; Brake, J; Bruzual, J J; Gerard, P D

    2001-09-01

    There is a paucity of information regarding the influence of incubational humidity on the characteristics of broiler embryos from young hens that often produce chicks of marginal quality. Therefore, the effects of broiler breeder age (26, 28, and 30 wk) in young broiler breeders and incubator humidity (43, 53, and 63% RH) on embryonic growth between 16 and 21 d of incubation, hatching chick weight, and embryo and chick body compositions were evaluated. Hatching broiler chick BW at 21 d was lower for 26-wk-old breeders compared to those at 28 and 30 wk, and the lowest RH decreased relative wet embryo weight. Embryonic growth, on wet and DM bases, was increased in eggs from the youngest hens. Embryo moisture content (EM) was lower at 16, 17, and 19 d of incubation in eggs from breeders at 26 wk when compared to those at 28 wk of age. The effects of RH on embryo crude protein and fat composition were not consistent and varied with breeder age and length of incubation. It was demonstrated that broiler breeder age affects embryogenesis and hatching chick BW. Furthermore, EM was influenced by breeder age, and changes in incubational RH between 43 and 63% affected embryogenesis without having associated effects on EM or consistent effects on embryo crude fat and protein content. Nevertheless, a depression in embryogenesis with a reduction in incubational RH to 43% may accentuate poor posthatch performance of chicks from young breeders.

  2. Tissue distribution of cells derived from the area opaca in heterospecific quail-chick blastodermal chimeras.

    PubMed

    Karagenç, Levent; Sandikci, Mustafa

    2010-01-01

    The objective of the current study was to determine the tissue distribution of cells derived from the area opaca in heterospecific quail-chick blastodermal chimeras. Quail-chick chimeras were constructed by transferring dissociated cells from the area opaca of the stage X-XII (EG&K) quail embryo into the subgerminal cavity of the unincubated chick blastoderm. The distribution of quail cells in embryonic as well as extra-embryonic tissues of the recipient embryo were examined using the QCPN monoclonal antibody after 6 days of incubation in serial sections taken at 100-mum intervals. Data gathered in the present study demonstrated that, when introduced into the subgerminal cavity of a recipient embryo, cells of the area opaca are able to populate not only extra-embryonic structures such as the amnion and the yolk sac, but also various embryonic tissues derived from the ectoderm and less frequently the mesoderm. Ectodermal chimerism was confined mainly to the head region and was observed in tissues derived from the neural ectoderm and the surface ectoderm, including the optic cup, diencephalon and lens. Although the possibility of random incorporation of transplanted cells into these embryonic structures cannot be excluded, these results would suggest that area opaca, a peripheral ring of cells in the avian embryo destined to form the extra-embryonic ectoderm and endoderm of the yolk sac, might harbor cells that have the potential to give rise to various cell types in the recipient chick embryo, including those derived from the surface ectoderm and neural ectoderm.

  3. Colour categorization by domestic chicks.

    PubMed

    Jones, C D; Osorio, D; Baddeley, R J

    2001-10-22

    Spectral stimuli form a physical continuum, which humans divide into discrete non-overlapping regions or categories that are designated by colour names. Little is known about whether non-verbal animals form categories on stimulus continua, but work in psychology and artificial intelligence provides models for stimulus generalization and categorization. We compare predictions of such models to the way poultry chicks (Gallus gallus) generalize to novel stimuli following appetitive training to either one or two colours. If the two training colours are (to human eyes) red and greenish-yellow or green and blue, chicks prefer intermediates, i.e. orange rather than red or yellow and turquoise rather than green or blue. The level of preference for intermediate colours implies that the chicks interpolate between the training stimuli. However, they do not extrapolate beyond the limits set by the training stimuli, at least for red and yellow training colours. Similarly, chicks trained to red and blue generalize to purple, but they do not generalize across grey after training to the complementary colours yellow and blue. These results are consistent with a modified version of a Bayesian model of generalization from multiple examples that was proposed by Shepard and show similarities to human colour categorization.

  4. A novel genetic hierarchy functions during hypaxial myogenesis: Pax3 directly activates Myf5 in muscle progenitor cells in the limb

    PubMed Central

    Bajard, Lola; Relaix, Frédéric; Lagha, Mounia; Rocancourt, Didier; Daubas, Philippe; Buckingham, Margaret E.

    2006-01-01

    We address the molecular control of myogenesis in progenitor cells derived from the hypaxial somite. Null mutations in Pax3, a key regulator of skeletal muscle formation, lead to cell death in this domain. We have developed a novel allele of Pax3 encoding a Pax3–engrailed fusion protein that acts as a transcriptional repressor. Heterozygote mouse embryos have an attenuated mutant phenotype, with partial conservation of the hypaxial somite and its myogenic derivatives, including some hindlimb muscles. At these sites, expression of Myf5 is compromised, showing that Pax3 acts genetically upstream of this myogenic determination gene. We have characterized a 145-base-pair (bp) regulatory element, at −57.5 kb from Myf5, that directs transgene expression to the mature somite, notably to myogenic cells of the hypaxial domain that form ventral trunk and limb muscles. A Pax3 consensus site in this sequence binds Pax3 in vitro and in vivo. Multimers of the 145-bp sequence direct transgene expression to sites of Pax3 function, and an assay of its activity in the chick embryo shows Pax3 dependence. Mutation of the Pax3 site abolishes all expression controlled by the 145-bp sequence in transgenic mouse embryos. We conclude that Pax3 directly regulates Myf5 in the hypaxial somite and its derivatives. PMID:16951257

  5. Migratory mechanisms of chick primordial germ cells toward gonadal anlage.

    PubMed

    Kuwana, T; Rogulska, T

    1999-07-01

    After appearing at the germinal crescent region, chick primordial germ cells (PGCs) migrate toward the presumptive gonads (pG) till stage 19 (Hamburger and Hamilton, 1951). This study seeks to elucidate the roles of passive and active factors in the PGC-migration, physical trapping of circulating PGCs by the capillary network and PGC attraction by chemotactic factor from presumptive gonads. Firstly, latex beads/pollens (the same size or larger than PGCs) were injected into the embryonic bloodstream at stage 13-19 (when PGCs are in the migrating and settlement phase to the presumptive gonad) in ovo in order to determine whether the PGCs passively reach pG. Most of such particles accumulated in the head region (60%), whereas the remainder did the same in the gonadal region (23% at the peak) at stage 16 when both the head and gonadal regions are rich in capillary plexus. After 3 days, most particles in the gonadal region were located at the angles of dorsal mesentery near the developing gonads where many extra-gonadal PGCs had been located, and a few particles were detected close to the gonad. These results suggest that one of the mechanisms of PGC-migration to the developing gonads is an autonomous trapping of PGCs by the capillary network quite close to the germinal epithelium (GE) and passive translocation by morphogenetic movement. Secondly, the attraction for PGCs by the gonadal anlage proper was examined in ovo using chick and quail embryos. Grafts of quail gonadal anlage containing gonadal epithelium and neighbouring mesenchymal tissue were excised from the quail embryo at stages 12 to 16 (staging by Zacchei, 1961). With the aims of eliminating the influence of surrounding tissue, the quail graft was ectopically transplanted into the posterior to the optic vesicle of 8 to 17 somite chick embryo from the point of a posterior region to the auditory vesicle by a fine tungsten needle under the illumination by the method of Hara (1971). Then the region posterior to

  6. The avian embryo responding to microgravity of space flight

    NASA Technical Reports Server (NTRS)

    Hullinger, Ronald L.

    1993-01-01

    Of all the many potential and real microenvironmental influences, only gravity would appear to have remained relatively constant and ubiquitous for developing organisms. Histo- and organogenesis as well as differential growth of the embryo and fetus may have evolved with a constant environmental factor of gravity. Chick embryos of 2-day and 9-day stages of incubation were flown in an incubator on the Space Shuttle during a 9-day mission. Significant differences in embryo response to this microgravity environment were observed. This paper offers an analysis and suggests mechanisms which may contribute to these results.

  7. The effects of incubation temperature on the sex of Japanese quail chicks.

    PubMed

    Yilmaz, A; Tepeli, C; Garip, M; Caglayan, T

    2011-10-01

    The effects of incubation temperature on the sex of Japanese quail chicks were investigated in this study. The study was conducted on Japanese quail. In all, 4500 eggs obtained from 2 generations were used. At the beginning of the study, a new flock was formed from available hatching eggs. Hatching eggs were gathered at 3 different ages (8 to 10 weeks, 16 to 18 weeks and 22 to 24 weeks of age) from the laying period in this flock. These eggs were exposed to 5 different incubation temperatures (36.7, 37.2, 37.7, 38.2, and 38.7°C). The hatching results were evaluated for each group. Chicks obtained from these temperature groups were reared separately to obtain quail for breeding. Eggs for incubation were gathered from these breeding quail when they were between 15 and 18 weeks of age. These eggs were placed in an incubator at a standard (37.7°C) temperature, separated by F(1)-generation temperature groups. The chicks in all groups were reared separately, and the sex of the chicks was determined at maturity. Statistical differences (P < 0.05) were found for the sex of the chicks in the third group (22 to 24 weeks) of the F(1) generation, compared with other groups. This result confirmed the hypothesis that different incubation temperatures for the first generation (at the embryo stage) might influence the sex of the next generation of chicks. Further studies are needed to investigate the effects of incubation temperature on chicks from different perspectives.

  8. Variations in growth of roseate tern chicks

    USGS Publications Warehouse

    Nisbet, I.C.T.; Spendelow, J.A.; Hatfield, J.S.

    1995-01-01

    We measured growth parameters of Roseate Tern (Sterna dougallii) chicks at two contrasting colonies: Bird Island, Massachusetts, and Falkner Island, Connecticut, from 1987 through 1990. Differences in growth parameters among individual chicks are used to explore differences in parental performance, whereas differences in average growth parameters among colonies and years are used to explore differences in average environmental conditions. Chicks were marked at hatching and weighed at one- or two-day intervals. For each chick that survived to fledging, we calculated two measures of growth: linear growth rate and asymptotic mass. There were no significant differences between growth parameters of first-hatched chicks in broods of one and two. Both measures of growth were significantly lower and more variable for second-hatched chicks than for first-hatched chicks. Both measures were significantly positively related to egg mass and negatively related to hatch date. After controlling for these variables, differences between colonies and among years were relatively small and inconsistent. Mean survival of second-hatched chicks was positively correlated with the mean growth rate of survivors across colonies and years. These findings are consistent with a general hypothesis that growth of chicks reflects individual parental performance and parental quality.

  9. Antioxidants safeguard telomeres in bold chicks

    PubMed Central

    Kim, Sin-Yeon; Velando, Alberto

    2015-01-01

    Telomeres are sensitive to damage induced by oxidative stress, and thus it is expected that dietary antioxidants may support the maintenance of telomere length in animals, particularly those with a fast rate of life (e.g. fast metabolism, activity and growth). We tested experimentally the effect of antioxidant supplements on telomere length during early development in wild gull chicks with natural individual variations in behaviour pattern and growth rate. Proactive chicks had shorter telomeres than reactive chicks, but the penalty for the bold behaviour pattern was reduced by antioxidant supplementation. Chicks growing faster had longer telomeres during early growth, suggesting that inherited quality supports a fast life history. PMID:25948570

  10. Lack of embryotoxicity of homocysteine thiolactone in mouse embryos in vitro.

    PubMed

    Hansen, D K; Grafton, T F; Melnyk, S; James, S J

    2001-01-01

    Recent work from humans and chick embryos has suggested that homocysteine may play a role in producing neural tube defects (NTDs). In an effort to determine if homocysteine is able to produce NTDs in mammalian embryos, mouse embryos were explanted on GD 8 and cultured for 44 h. When either homocysteine or homocysteine thiolactone was added to the culture medium, treated embryos developed as well as controls and had closed neural tubes. Homocysteine thiolactone was also microinjected into the amniotic sac of mouse embryos. Again, development proceeded normally with no significant increase in the number of embryos with open neural tubes at the end of the culture period. HPLC analysis of embryonic thiols 24 h after microinjection revealed a significant increase in embryonic cystathionine levels. These data suggest that homocysteine does not produce NTDs in mouse embryos cultured in vitro and that early organogenesis-stage embryos are able to metabolize homocysteine.

  11. Knockdown of Ephrin-A5 Expression by 40% Does not Affect Motor Axon Growth or Migration into the Chick Hindlimb

    PubMed Central

    Winning, Robert S.; Krull, Catherine E.

    2011-01-01

    Bidirectional signaling between Eph receptor tyrosine kinases and their cell-surface protein signals, the ephrins, comprises one mechanism for guiding motor axons to their proper targets. During projection of motor axons from the lateral motor column (LMC) motor neurons of the spinal cord to the hindlimb muscles in chick embryos, ephrin-A5 has been shown to be expressed in the LMC motor axons until they reach the base of the limb bud and initiate sorting into their presumptive dorsal and ventral nerve trunks, at which point expression is extinguished. We tested the hypothesis that this dynamic pattern of ephrin-A5 expression in LMC motor axons is important for the growth and guidance of the axons to, and into, the hindlimb by knocking down endogenous ephrin-A5 expression in the motor neurons and their axons. No perturbation of LMC motor axon projections was observed in response to this treatment, suggesting that ephrin-A5 is not needed for LMC motor axon growth or guidance. PMID:22272077

  12. Thalidomide induces limb defects by preventing angiogenic outgrowth during early limb formation.

    PubMed

    Therapontos, Christina; Erskine, Lynda; Gardner, Erin R; Figg, William D; Vargesson, Neil

    2009-05-26

    Thalidomide is a potent teratogen that induces a range of birth defects, most commonly of the developing limbs. The mechanisms underpinning the teratogenic effects of thalidomide are unclear. Here we demonstrate that loss of immature blood vessels is the primary cause of thalidomide-induced teratogenesis and provide an explanation for its action at the cell biological level. Antiangiogenic but not antiinflammatory metabolites/analogues of thalidomide induce chick limb defects. Both in vitro and in vivo, outgrowth and remodeling of more mature blood vessels is blocked temporarily, whereas newly formed, rapidly developing, angiogenic vessels are lost. Such vessel loss occurs upstream of changes in limb morphogenesis and gene expression and, depending on the timing of drug application, results in either embryonic death or developmental defects. These results explain both the timing and relative tissue specificity of thalidomide embryopathy and have significant implications for its use as a therapeutic agent.

  13. Dimeric combinations of MafB, cFos and cJun control the apoptosis-survival balance in limb morphogenesis.

    PubMed

    Suda, Natsuno; Itoh, Takehiko; Nakato, Ryuichiro; Shirakawa, Daisuke; Bando, Masashige; Katou, Yuki; Kataoka, Kohsuke; Shirahige, Katsuhiko; Tickle, Cheryll; Tanaka, Mikiko

    2014-07-01

    Apoptosis is an important mechanism for sculpting morphology. However, the molecular cascades that control apoptosis in developing limb buds remain largely unclear. Here, we show that MafB was specifically expressed in apoptotic regions of chick limb buds, and MafB/cFos heterodimers repressed apoptosis, whereas MafB/cJun heterodimers promoted apoptosis for sculpting the shape of the limbs. Chromatin immunoprecipitation sequencing in chick limb buds identified potential target genes and regulatory elements controlled by Maf and Jun. Functional analyses revealed that expression of p63 and p73, key components known to arrest the cell cycle, was directly activated by MafB and cJun. Our data suggest that dimeric combinations of MafB, cFos and cJun in developing chick limb buds control the number of apoptotic cells, and that MafB/cJun heterodimers lead to apoptosis via activation of p63 and p73.

  14. RNA Interference in Chicken Embryos

    NASA Astrophysics Data System (ADS)

    van Hateren, Nick J.; Jones, Rachel S.; Wilson, Stuart A.

    The chicken has played an important role in biological discoveries since the 17th century (Stern, 2005). Many investigations into vertebrate development have utilized the chicken due to the accessibility of the chick embryo and its ease of manipulation (Brown et al., 2003). However, the lack of genetic resources has often handicapped these studies and so the chick is frequently overlooked as a model organism for the analysis of vertebrate gene function in favor of mice or zebrafish. In the past six years this situation has altered dramatically with the generation of over half a million expressed sequence tags and >20,000 fully sequenced chicken cDNAs (Boardman et al. 2002; Caldwell et al., 2005; Hubbard et al., 2005) together with a 6X coverage genome sequence (Hillier et al., 2004). These resources have created a comprehensive catalogue of chicken genes with readily accessible cDNA and EST resources available via ARK-GENOMICS (www.ark-genomics.org) for the functional analysis of vertebrate gene function.

  15. Interferon Production and Protein Synthesis in Chick Cells

    PubMed Central

    Friedman, Robert M.

    1966-01-01

    Friedman, Robert M. (National Cancer Institute, Bethesda, Md.). Interferon production and protein synthesis in chick cells. J. Bacteriol. 91:1224–1229. 1966.—Overnight incubation of chick embryo fibroblasts (CEF) at 4 C before infection with live Semliki Forest virus (SFV) increased virus yields but decreased interferon production. The same findings were noted when CEF were incubated for 4 hr with p-fluorophenylalanine (FPA) before infection with live SFV or inactivated Chikungunya virus. In both systems incorporation of C14-leucine into protein appeared to be increased after pretreatment at 4 C or with FPA. Protein synthesis could be raised in CEF incubated in 0.5% serum after trypsinization by increasing the concentration of serum. CEF in 10% serum had higher rates of C14-leucine incorporation than did cells in 1.5% serum, but again the cells with the apparently high rate of incorporation produced less interferon. These findings may be related to the mechanism of cellular control over interferon production. PMID:5929753

  16. Vanadium reduces mortality in phosphorus deficient chicks

    SciTech Connect

    Hill, C.H. )

    1991-03-15

    Since the vanadate anion is similar in structure to the phosphate ion, and since vanadate has been shown to interfere with phosphate metabolism both in vitro and in vivo, experiments were conducted to determine the effect of dietary vanadate (V) on chicks fed phosphorus (P) deficient diets. In these studies, broiler chicks of both sexes were fed the experimental diets from the day of hatching for 19 days. The diets were based on soybean meal and corn, supplemented with methionine, manganese, and vitamins to supply the chick's requirements. Calcium (Ca) and P levels were manipulated by use of feed grade dicalcium phosphate and limestone. V was added as ammonium metavanadate. Serum Ca and P were determined on representative chicks in each group. Increasing Ca levels increased serum Ca and decreased serum P. V increased serum P levels in the chicks receiving 0.2% P but not in those receiving 0.1% P.

  17. Lipid synthesis in chick epidermis.

    PubMed

    Lavker, R M

    1975-07-01

    Lipid synthesis in newborn chick epidermis was studied by electron microscopic autoradiography after injection of tritiated palmitate. The labeled lipid product in the tissue was identified as mostly triglyceride. At the earliest time after injection (6 hr), the radioactive precursor was taken up by all viable cells of the epidermis. Grain density was heaviest over basal cells, moderate over spinous cells, and slight over granular cells; thus lipid incorporation is highest in the basal and spinous regions of the chick epidermis. As time after injection progressed, the increasing amounts of grains over the granular and horny cells and decreasing amounts over the basal and spinous cells reflected the continuous upward displacement of cells from one layer into the next. From the distribution of silver grains within the epidermal cells, it has been concluded that, with the passage of time, triglycerides synthesized by the epidermal cells were mainly located in lipid droplets. The numerous grains associated with the elements of the endoplasmic reticulum indicated that this organelle is involved in aggregating triglyceride molecules into lipid droplets. The fact that grains were seen within the horny cells indicated that part of the horny cell consists of lipid probably derived from the lipid droplets retained by the cells during keratinization. PMID:1151110

  18. Isolation of Infectious Bursal Disease Virus Using Indigenous Chicken Embryos in Kenya

    PubMed Central

    Mutinda, W. U.; Njagi, L. W.; Nyaga, P. N.; Bebora, L. C.; Mbuthia, P. G.; Kemboi, D.; Githinji, J. W. K.; Muriuki, A.

    2015-01-01

    Infectious bursal disease virus (IBDV) isolates were recovered from outbreaks to initiate activities towards developing a local vaccine strain. Use of indigenous chicken embryos was exploited to determine their potential, promote utilization of local resources for research, and enhance household economic activities. Bursa of Fabricius (BFs) samples from outbreaks shown to be IBDV positive was homogenized and inoculated in 4-week-old specific pathogen-free (SPF) IBDV seronegative white leghorn chicks. The harvested virus was inoculated into 11-day-old indigenous chicken embryos that were IBDV seronegative and passaged serially three times after which they were inoculated into 4-week-old indigenous chicks to test for presence and virulence of propagated virus. Out of 153 BFs collected from outbreaks, 43.8% (67/153) were positive for IBDV antigen and 65.7% (44/67) caused disease in SPF chicks. The embryo mean mortalities were 88% on primary inoculation, 94% in 1st passage, 91% in 2nd passage, and 67% in 3rd passage. After the third passage in embryos all the 44 isolates were virulent in 4-week-old indigenous chicks. The results show that indigenous chicken embryos support growth of IBDV and can be used to propagate the virus as an alternative viral propagating tool for respective vaccine preparation. PMID:27347520

  19. Cell Cycle Regulation and Apoptotic Responses of the Embryonic Chick Retina by Ionizing Radiation

    PubMed Central

    Layer, Paul G.; Frohns, Florian

    2016-01-01

    Ionizing radiation (IR) exerts deleterious effects on the developing brain, since proliferative neuronal progenitor cells are highly sensitive to IR-induced DNA damage. Assuming a radiation response that is comparable to mammals, the chick embryo would represent a lower vertebrate model system that allows analysis of the mechanisms underlying this sensitivity, thereby contributing to the reduction, refinement and replacement of animal experiments. Thus, this study aimed to elucidate the radiation response of the embryonic chick retina in three selected embryonic stages. Our studies reveal a lack in the radiation-induced activation of a G1/S checkpoint, but rapid abrogation of G2/M progression after IR in retinal progenitors throughout development. Unlike cell cycle control, radiation-induced apoptosis (RIA) showed strong variations between its extent, dose dependency and temporal occurrence. Whereas the general sensitivity towards RIA declined with ongoing differentiation, its dose dependency constantly increased with age. For all embryonic stages RIA occurred during comparable periods after irradiation, but in older animals its maximum shifted towards earlier post-irradiation time points. In summary, our results are in good agreement with data from the developing rodent retina, strengthening the suitability of the chick embryo for the analysis of the radiation response in the developing central nervous system. PMID:27163610

  20. Growth patterns of Hawaiian Stilt chicks

    USGS Publications Warehouse

    Reed, J.M.; Gray, E.M.; Lewis, D.; Oring, L.W.; Coleman, R.; Burr, T.; Luscomb, P.

    1999-01-01

    We studied chick growth and plumage patterns in the endangered Hawaiian Stilt (Himantopus mexicanus knudseni). Body mass of captive chicks closely fit a Gompertz growth curve, revealing a growth coefficient (K) of 0.065 day-1 and point of inflection (T) of 17 days. When chicks fledged about 28 days after hatching, they weighed only 60% of adult body mass; at 42 d, birds still were only 75% of adult mass; culmen, tarsus, and wing chord at fledging also were less than adult size. This trend of continued growth to adult size after fledging is typical for most shorebirds. After hatching, captive chicks grew more rapidly than wild chicks, probably because of an unlimited food supply. We found no evidence for adverse effects of weather on the growth of wild chicks. As with other shorebirds, the tarsus started relatively long, with culmen and then wing chord growing more rapidly in later development. Tarsal and wing chord growth were sigmoidal, whereas culmen growth was linear. We describe plumage characteristics of weekly age classes of chicks to help researchers age birds in the wild.

  1. Deciphering skeletal patterning: clues from the limb.

    PubMed

    Mariani, Francesca V; Martin, Gail R

    2003-05-15

    Even young children can distinguish a Tyrannosaurus rex from a Brontosaurus by observing differences in bone size, shape, number and arrangement, that is, skeletal pattern. But despite our extensive knowledge about cartilage and bone formation per se, it is still largely a mystery how skeletal pattern is established. Much of what we do know has been learned from studying limb development in chicken and mouse embryos. Based on the data from such studies, models for how limb skeletal pattern is established have been proposed and continue to be hotly debated.

  2. Generation of aneurogenic larvae by parabiosis of salamander embryos.

    PubMed

    Kumar, Anoop; Delgado, Jean Paul

    2015-01-01

    Limb regeneration of salamanders is nerve dependent, and the removal of the nerves in early stages of limb regeneration severely curtails the proliferation of the blastemal cells and growth of the regenerate. The removal of the neural tube from a developing salamander embryo results in an aneurogenic larva and the aneurogenic limb (ANL) develops independently without innervation. Paradoxically, the limb in an ANL is capable of regeneration in a nerve-independent manner. Here, we describe a detailed method for the generation of ANL in the spotted salamander, Ambystoma maculatum, for regeneration studies.

  3. The Sonic hedgehog gradient in the developing limb.

    PubMed

    Tickle, Cheryll; Barker, Heather

    2013-01-01

    A gradient of Sonic hedgehog (Shh) plays a major role in specifying the antero-posterior pattern of structures that develop in the distal part of the vertebrate limb, in particular, the antero-posterior pattern of the digits. Classical embryological experiments identified the polarizing region (or zone of polarizing activity, ZPA), a signaling region at the posterior margin of the early chick wing bud and, consistent with a model in which production of a diffusible morphogen specifies antero-posterior positional information, polarizing region signaling was shown to be dose dependent and long range. It is now well established that the vertebrate hedgehog gene, Sonic hedgehog (Shh), which encodes a secreted protein, is expressed in the polarizing region of the chick wing and that Shh signaling has the same characteristics as polarizing region signaling. Shh expression at the posterior of the early limb bud and the mechanism of Shh signal transduction are conserved among vertebrates including mammals. However, it is unlikely that a simple Shh gradient is responsible for digit pattern formation in mammalian limbs and there is still little understanding of how positional information specified by Shh signaling is encoded and translated into digit anatomy. Alterations in Shh signaling underlie some congenital limb abnormalities and also changes in timing and extent of Shh signaling appear to be related to the evolution of morphological diversity of vertebrate limbs.

  4. The birth of quail chicks after intracytoplasmic sperm injection.

    PubMed

    Mizushima, Shusei; Hiyama, Gen; Shiba, Kogiku; Inaba, Kazuo; Dohra, Hideo; Ono, Tamao; Shimada, Kiyoshi; Sasanami, Tomohiro

    2014-10-01

    Intracytoplasmic sperm injection (ICSI) has been successfully used to produce offspring in several mammalian species including humans. However, ICSI has not been successful in birds because of the size of the egg and difficulty in mimicking the physiological polyspermy that takes place during normal fertilization. Microsurgical injection of 20 or more spermatozoa into an egg is detrimental to its survival. Here, we report that injection of a single spermatozoon with a small volume of sperm extract (SE) or its components led to the development and birth of healthy quail chicks. SE contains three factors - phospholipase Cζ (PLCZ), aconitate hydratase (AH) and citrate synthase (CS) - all of which are essential for full egg activation and subsequent embryonic development. PLCZ induces an immediate, transient Ca(2+) rise required for the resumption of meiosis. AH and CS are required for long-lasting, spiral-like Ca(2+) oscillations within the activated egg, which are essential for cell cycle progression in early embryos. We also found that co-injection of cRNAs encoding PLCZ, AH and CS support the full development of ICSI-generated zygotes without the use of SE. These findings will aid our understanding of the mechanism of avian fertilization and embryo development, as well as assisting in the manipulation of the avian genome and the production of transgenic and cloned birds.

  5. Increase in S-adenosyl-L-methionine decarboxylase activity during the transformation of chick embroy fibroblasts by Rous sarcoma virus.

    PubMed

    Bachrach, U; Weiner, H

    1980-07-15

    The increase in S-adenosyl-L-methionine decarboxylase activity in chick embryo fibroblasts after infection with Rous sarcoma virus has been studied. It has been shown that enzyme levels in transformed cells were two or three times higher than those of the non-infected controls. The activity of this enzyme was not elevated in chick embryo fibroblasts infected with a temperature sensitive mutant of Rous sarcoma virus (RSV-T5) at 42 degrees C, the non-permissive temperature. When the temperature of these infected cultures was shifted from 42 degrees C to 37 degrees C a two- or three-fold increase in decarboxlase activity was detected after 10 to 12 h. The half-live of S-adenosyl-L-methionine decarboxylase was practically identical in normal and RSV-transformed fibroblasts.

  6. A novel, nonsurgical method for the treatment of tibiotarsal rotation in houbara bustard (Chlamydotis macqueenii) chicks.

    PubMed

    Stiévenart, Corinne

    2008-03-01

    Rotational limb deformity due to tibiotarsal rotation can affect captive-bred houbara bustard chicks (Chlamydotis macqueenii) from an early age. If not completely corrected, the affected birds can neither be released into the wild nor used in captive-breeding projects. A nonsurgical orthopedic method was developed to correct this deformity before growth is completed. The method consists of hobbling digits III and the distal part of the tarsometatarsus of each leg with a self-adhesive conforming bandage that keeps digits III parallel with enough freedom of movement to allow walking. The tibiotarsal bones are left free. This treatment was successful when it was implemented for 20 days on 10-day-old houbara bustard chicks presenting with 60 degrees to 90 degrees unilateral tibiotarsal rotation. Implementing the same corrective method at an older age was not successful. This cheap, accessible, and noninvasive technique may be applicable to other avian species. PMID:18543599

  7. A novel, nonsurgical method for the treatment of tibiotarsal rotation in houbara bustard (Chlamydotis macqueenii) chicks.

    PubMed

    Stiévenart, Corinne

    2008-03-01

    Rotational limb deformity due to tibiotarsal rotation can affect captive-bred houbara bustard chicks (Chlamydotis macqueenii) from an early age. If not completely corrected, the affected birds can neither be released into the wild nor used in captive-breeding projects. A nonsurgical orthopedic method was developed to correct this deformity before growth is completed. The method consists of hobbling digits III and the distal part of the tarsometatarsus of each leg with a self-adhesive conforming bandage that keeps digits III parallel with enough freedom of movement to allow walking. The tibiotarsal bones are left free. This treatment was successful when it was implemented for 20 days on 10-day-old houbara bustard chicks presenting with 60 degrees to 90 degrees unilateral tibiotarsal rotation. Implementing the same corrective method at an older age was not successful. This cheap, accessible, and noninvasive technique may be applicable to other avian species.

  8. Misexpression of BRE gene in the developing chick neural tube affects neurulation and somitogenesis

    PubMed Central

    Wang, Guang; Li, Yan; Wang, Xiao-Yu; Chuai, Manli; Yeuk-Hon Chan, John; Lei, Jian; Münsterberg, Andrea; Lee, Kenneth Ka Ho; Yang, Xuesong

    2015-01-01

    The brain and reproductive expression (BRE) gene is expressed in numerous adult tissues and especially in the nervous and reproductive systems. However, little is known about BRE expression in the developing embryo or about its role in embryonic development. In this study, we used in situ hybridization to reveal the spatiotemporal expression pattern for BRE in chick embryo during development. To determine the importance of BRE in neurogenesis, we overexpressed BRE and also silenced BRE expression specifically in the neural tube. We established that overexpressing BRE in the neural tube indirectly accelerated Pax7+ somite development and directly increased HNK-1+ neural crest cell (NCC) migration and TuJ-1+ neurite outgrowth. These altered morphogenetic processes were associated with changes in the cell cycle of NCCs and neural tube cells. The inverse effect was obtained when BRE expression was silenced in the neural tube. We also determined that BMP4 and Shh expression in the neural tube was affected by misexpression of BRE. This provides a possible mechanism for how altering BRE expression was able to affect somitogenesis, neurogenesis, and NCC migration. In summary, our results demonstrate that BRE plays an important role in regulating neurogenesis and indirectly somite differentiation during early chick embryo development. PMID:25568339

  9. Effect of gestational ethanol exposure on parvalbumin and calretinin expressing hippocampal neurons in a chick model of fetal alcohol syndrome.

    PubMed

    Marshall, Audrey G; McCarthy, Molly M; Brishnehan, Kirk M; Rao, Venugopal; Batia, Lyn M; Gupta, Madhul; Das, Srijit; Mitra, Nilesh K; Chaudhuri, Joydeep D

    2009-03-01

    Fetal alcohol syndrome (FAS), a condition occurring in some children of mothers who have consumed alcohol during pregnancy, is characterized by physical deformities and learning and memory deficits. The chick hippocampus, whose functions are controlled by interneurons expressing calcium-binding proteins parvalbumin (PV) and calretinin (CR), is involved in learning and memory mechanisms. Effects on growth and development and hippocampal morphology were studied in chick embryos exposed to 5% and 10% ethanol volume/volume (vol/vol) for 2 or 8 days of gestation. There was a significant dose-dependent reduction (P<.05) in body weight and mean number per section of PV and CR expressing hippocampal neurons in ethanol-exposed chicks, without alterations in neuronal nuclear size or hippocampal volume, compared appropriate controls. Moreover, when chicks exposed to 5% ethanol for 2 and 8 days of gestation were compared, no significant differences were found in body parameters or neuronal counts. Similarly, exposure to 10% ethanol did not induce any significant changes in chicks exposed for 2 or 8 gestational days. Thus, these results suggest that gestational ethanol exposure induces a reduction in the mean number per section of PV and CR expressing hippocampal neurons, and could be a possible mechanism responsible for learning and memory disorders in FAS.

  10. Effects of experimentally increased in ovo lysozyme on egg hatchability, chicks complement activity, and phenotype in a precocial bird.

    PubMed

    Javůrková, Veronika; Krkavcová, Eva; Kreisinger, Jakub; Hyršl, Pavel; Hyánková, Ludmila

    2015-10-01

    In birds, spectrum of egg white proteins deposited into the egg during its formation are thought to be essential maternal effects. Particularly, egg white lysozyme (LSM), exhibiting great between and within species variability, is considered to be essential for developing avian embryos due to its physiological, antimicrobial, and innate immune defense functions. However, there have been few studies investigating effects of LSM on early post-hatching phenotype, despite its broad physiological and protective role during embryogenesis. Here, we test how experimentally increased concentrations of egg white LSM affect hatchability in Japanese quail (Coturnix japonica) and chick phenotype immediately after hatching (particularly body weight, tarsus length, plasma LSM concentration, and plasma complement activity). Chicks from eggs with increased LSM concentration displayed reduced tarsus length compared to chicks from control eggs while hatchability, body weight and plasma LSM concentration were unaffected. It is worth noting that no effect of increased in ovo lysozyme on eggs hatchability could be related to pathogen-free environment during artificial incubation of experimental eggs causing minimal pressure on embryo viability. While tangible in vivo mechanisms during avian embryogenesis remain to be tested, our study is the first to document experimentally that egg white LSM appears to have growth-regulation role during embryo development, with possible underlying phenotypic consequences in the early post-hatching period in precocial birds.

  11. Polymelous layer chick displaying additional malformations of the hind gut: case report and in-depth review of related literature.

    PubMed

    Hirschberg, R M; Saleh, M; Kaiser, S; Lierz, M; Hafez, H M; Bragulla, H H

    2012-08-01

    A case report of a male 6-day-old male layer chick featuring incomplete polymelia of the hind limbs and hindgut malformations is presented. The chick was submitted to computed tomography (CT) examination and subsequent anatomical dissection. Apart from the two supernumerary hind limbs, the anatomical dissection revealed additional hindgut alterations: three uniform-sized caeca flanked the ileum, and the rectum branched into paired cloacae. The supernumerary hind limbs were localized caudal to the normal hind limbs in an inverted position and were attached to pelvic girdle elements and to a curtate pygostyle. They featured a prominent unpaired femur besides paired tibiotarsi, tarsometatarsi and species-specific phalanges of the toes. Additionally, two separate bones attached to the caudoventral aspect of the regular hip bones were developed. The supernumerary limbs were in part mobile and received nerve and vascular supply. Digital 3D-reconstruction based on the CT datasets revealed the osseous components of the malformed body parts. The possible morphogenesis including an in-depth literature review and the clinical implications of the reported malformations are discussed. PMID:22250842

  12. Regional differences in myelination of chick vestibulocochlear ganglion cells.

    PubMed

    Sun, Ying-Jie; Kobayashi, Hiroto; Yoshida, Saori; Shirasawa, Nobuyuki; Naito, Akira

    2013-11-01

    In vertebrates, vestibular and cochlear ganglion (VG and CG, respectively) cells are bipolar neurons with myelinated axons and perikarya. The time course of the myelination of the VG and CG cells during development of chick embryos was investigated. Chick VG and CG from embryonic day at 7-20 (E7-20) were prepared for a transmission electron microscopy, myelin basic protein immunohistochemistry, and real-time quantitative RT-PCR. In the VG cells, myelination was first observed on the peripheral axons of the ampullar nerves at E10, on the utricular and saccular nerves at E12, and on the lagenar and neglecta nerves at E13. In the VG central axons, myelination was first seen on the ampullar nerves at E11, on the utricular and saccular nerves at E13, and on the lagenar nerves at E13. In the CG cells, the myelination was first observed on the peripheral and central axons at E14. In both VG and CG, myelination was observed on the perikarya at E17. These results suggest that the onset of the axonal myelination on the VG cells occurred earlier than that on the CG cells, whereas the perikaryal myelination occurred at about the same time on the both types of ganglion cells. Moreover, the myelination on the ampullar nerves occurred earlier than that on the utricular and saccular nerves. The myelination on the peripheral axons occurred earlier than that on the central axons of the VG cells, whereas that on the central and peripheral axons of the CG cells occurred at about the same time. The regional differences in myelination in relation to the onset of functional activities in the VG and CG cells are discussed.

  13. Avian maternal response to chick distress

    PubMed Central

    Edgar, J. L.; Lowe, J. C.; Paul, E. S.; Nicol, C. J.

    2011-01-01

    The extent to which an animal is affected by the pain or distress of a conspecific will depend on its capacity for empathy. Empathy most probably evolved to facilitate parental care, so the current study assessed whether birds responded to an aversive stimulus directed at their chicks. Domestic hens were exposed to two replicates of the following conditions in a counterbalanced order: control (C; hen and chicks undisturbed), air puff to chicks (APC; air puff directed at chicks at 30 s intervals), air puff to hen (APH; air puff directed at hen at 30 s intervals) and control with noise (CN; noise of air puff at 30 s intervals). During each test, the hens' behaviour and physiology were measured throughout a 10 min pre-treatment and a 10 min treatment period. Hens responded to APH and APC treatments with increased alertness, decreased preening behaviour and a reduction in eye temperature. No such changes occurred during any control period. Increased heart rate and maternal vocalization occurred exclusively during the APC treatment, even though chicks produced few distress vocalizations. The pronounced and specific reaction observed indicates that adult female birds possess at least one of the essential underpinning attributes of empathy. PMID:21389025

  14. Endogenous electric fields in embryos during development, regeneration and wound healing.

    PubMed

    Nuccitelli, R

    2003-01-01

    All embryos that have been investigated drive ionic currents through themselves and these currents will generate internal electric fields. Here, those examples in which such fields have been measured directly are discussed. The first such measurements were made in chick embryos and about 20 mV mm(-1) was measured near the posterior intestinal portal in 2-4 day-old embryos. This electric field is important for the development of tail structures because reducing its magnitude results in abnormal tail development. The second embryonic electric field measured directly was in the axolotl, where a rostral-caudal field of about the same magnitude was detected. Modification of this field during neurulation but not gastrulation caused developmental abnormalities. Most recently, the development of left-right asymmetry in frog and chick embryos was found to require a voltage difference between blastomeres at a very early developmental stage. This field was measured in the chick embryo to be 10-20 mV mm(-1) across the primitive streak. Mammalian skin wounds generate 150 mV mm(-1) fields lateral to the wound and corneal epidermal wounds exhibit lateral fields of 40 mV mm(-1). The presence of these endogenous fields would suggest that exposures to external electric fields should be limited to magnitudes of less than 0.1 V m(-1). PMID:14690282

  15. Knockdown of Lmo7 inhibits chick myogenesis.

    PubMed

    Possidonio, Ana C B; Soares, Carolina P; Fontenele, Marcio; Morris, Eduardo R; Mouly, Vincent; Costa, Manoel L; Mermelstein, Claudia

    2016-02-01

    The multifunctional protein Lmo7 has been implicated in some aspects of myogenesis in mammals. Here we studied the distribution and expression of Lmo7 and the effects of Lmo7 knockdown in primary cultures of chick skeletal muscle cells. Lmo7 was localized within the nuclei of myoblasts and at the perinuclear region of myotubes. Knockdown of Lmo7 using siRNA specific to chick reduces the number and width of myotubes and the number of MyoD positive-myoblasts. Both Wnt3a enriched medium and Bio, activators of the Wnt/beta-catenin pathway, could rescue the effects of the Lmo7 knockdown suggesting a crosstalk between the Wnt/beta-catenin and Lmo7-mediated signaling pathways. Our data shows a role of Lmo7 during the initial events of chick skeletal myogenesis, particularly in myoblast survival.

  16. Isolation of the mature subunit of delta-aminolaevulinate synthase from embryonic chick liver.

    PubMed Central

    Ades, I Z; Harpe, K G

    1982-01-01

    We presented evidence indicating that the established procedure for purifying delta-aminolaevulinate (ALA) synthase from embryonic-chick liver yielded an enzyme with a partially degraded subunit of molecular weight 51000 [Ades & Harpe (1981) J. Biol. Chem. 256, 9329-9333]. We now report the purification from livers of porphyric embryos of a preparation of ALA synthase which consisted primarily of a 63000-Da polypeptide and a component migrating as a smear of polypeptides with a minimum molecular weight of 52 000. Neither component could be recovered from liver mitochondria of normal embryos, where the amounts of ALA synthase were relatively low. The 52 000-Da component had been established to be the partially degraded subunit of the enzyme. Peptide-mapping analyses indicated that the 63 000- and the 52 000-Da components possessed significant structural homologies, and it was concluded that the 63 000-Da polypeptide represented the mature subunit of ALA synthase. Images Fig. 1. Fig. 3. PMID:7138500

  17. Changes in haemoglobin and antigenic constitution of erythrocytes during embryonic and postembryonic chick development.

    PubMed

    Godet, J; Blanchet, J P; Nigon, V

    1976-01-01

    Between the 18th and 20th day of incubation, the proportion of haemoglobin F (Hb F) synthesis decreases in the embryo bone marrow from the value found in the yolk sac (10% of the total haemoglobin synthesis) to the value found in the bone marrow of young chicks (2%). A similar drop in Hb F synthesis is observed with a delay of 48 hours in the blood. Two membrane antigens each specific of either embryo or adult erythrocytes have been detected. The study by immunofluorescence of their cellular distribution shows that 3 erythrocyte populations are successively produced: a population E bearing the embryonic antigen only, a population EA bearing both antigens and a population A bearing the adult antigen only. The presence of a relatively high proportion of Hb F in population E is strongly suggested by the similar kinetics of Hb F and E cells disappearance within the first posthatching month.

  18. Acetazolamide does not disrupt limb regenerate morphogenesis in the salamander, Plethodon cinereus.

    PubMed

    Dinsmore, C E; Maren, T H

    1986-02-01

    Acetazolamide, a potent and highly specific inhibitor of carbonic anhydrase, is teratogenic in mammalian embryos and when administered during early limb development causes unique limb defects in a time- and dose-dependent manner. The regenerating urodele limb is often considered to be a good experimental analog of limb development and, if it employs the same mechanisms of tissue interactions during pattern formation, should be susceptible to teratogens which selectively disrupt developmental limb patterning. This study demonstrates that while carbonic anhydrase inhibition is toxic to the red-backed salamander, Plethodon cinereus, it does not have the same teratogenic effect on limb regeneration as seen in mammalian limb development. Several points are considered as to why the regenerating limb, at least in this salamander species, may not be suitable for studying this class of teratogen.

  19. Changes in yolk sac membrane absorptive area and fat digestion during chick embryonic development.

    PubMed

    Yadgary, L; Kedar, O; Adepeju, O; Uni, Z

    2013-06-01

    The capacity of yolk sac (YS) utilization by the chick embryo may be affected by structural changes in the YS membrane (YSM) and by the mechanisms within its cells for digestion, absorption, and transfer of nutrients. Two experiments were conducted to examine structural and digestive changes in the YS of the broiler chick embryo; weights of embryo, YS, and YSM, as well as the total area of the YSM and the absorptive area of the YSM, were measured between embryonic day (E) 5 and E21. In addition, fat content, lipase activity, and bile acid concentration in the YSM and YS contents (YSC) were measured between E11 and E21. Results showed that YSM weight increased from 0.19 g on E5 to 6.46 g on E15, and decreased by 3.74 g between E17 and E21. The absorptive YSM area increased from 536 mm² on E5 (51% of total YSM area) to 6,370 mm² (86% of total area) on E17, and decreased to 4,439 mm(2) on E21 (85% of total area). The smaller YSM area between E17 and E21 did not decrease the rate of YS fat utilization, which could suggest that YSM mechanisms for fat absorption, digestion, and secretion increased during that period. Total YSM lipase activity relative to fat content (units per g of YSM fat) increased from approximately 1,000 units on E15 to 1,500 units on E21. The detection of lipase in the YSM lends support to the hypothesis that YS lipids are hydrolyzed in the lipolysosomes of the YSM. The current study also confirmed for the first time that bile acids are present in the YS, with levels that ranged from 0.61 to 1.06 µmol/g in the YSM, and may suggest that bile is synthesized in the YSM of the chick embryo. Results of the current study contribute to our understanding of the developmental changes that affect YS functionality and could give insight into the coordination between the embryo's demands and YSM morphological, absorptive, digestive, and secretive changes.

  20. Mortality of Mississippi Sandhill Crane chicks

    USGS Publications Warehouse

    Olsen, G.H.

    2004-01-01

    Mississippi sandhill cranes (Grus canadensis pulla) are a highly endangered species that live in the wild in 1 county in Mississippi. As part of a large effort to restore these endangered cranes, we are conducting a project to look at the causes of mortality in crane chicks on the Mississippi Sandhill Crane National Wildlife Refuge in Gautier, MS, USA. This includes surgically implanting miniature radio transmitters in crane chicks to gather data on mortality. This article describes some of the practical difficulties in conducting this type of project in a savannah and swamp location along the Gulf Coast of the USA.

  1. Autophagy is involved in ethanol-induced cardia bifida during chick cardiogenesis

    PubMed Central

    Li, Shuai; Wang, Guang; Gao, Lin-rui; Lu, Wen-hui; Wang, Xiao-Yu; Chuai, Manli; Lee, Kenneth Ka Ho; Cao, Liu; Yang, Xuesong

    2015-01-01

    Excess alcohol consumption during pregnancy has been acknowledged to increase the incidence of congenital disorders, especially the cardiovascular system. However, the mechanism involved in ethanol-induced cardiac malformation in prenatal fetus is still unknown. We demonstrated that ethanol exposure during gastrulation in the chick embryo increased the incidence of cardia bifida. Previously, we reported that autophagy was involved in heart tube formation. In this context, we demonstrated that ethanol exposure increased ATG7 and LC3 expression. mTOR was found to be inhibited by ethanol exposure. We activated autophagy using exogenous rapamycin (RAPA) and observed that it induced cardiac bifida and increased GATA5 expression. RAPA beads implantation experiments revealed that RAPA restricted ventricular myosin heavy chain (VMHC) expression. In vitro explant cultures of anterior primitive streak demonstrated that both ethanol and RAPA treatments could reduce cell differentiation and the spontaneous beating of cardiac precursor cells. In addition, the bead experiments showed that RAPA inhibited GATA5 expression during heart tube formation. Semiquantitative RT-PCR analysis indicated that BMP2 expression was increased while GATA4 expression was suppressed. In the embryos exposed to excess ethanol, BMP2, GATA4 and FGF8 expression was repressed. These genes are associated with cardiomyocyte differentiation, while heart tube fusion is associated with increased Wnt3a but reduced VEGF and Slit2 expression. Furthermore, the ethanol exposure also caused the production of excess ROS, which might damage the cardiac precursor cells of developing embryos. In sum, our results revealed that disrupting autophagy and excess ROS generation are responsible for inducing abnormal cardiogenesis in ethanol-treated chick embryos. PMID:26317250

  2. Interaction of the substratum and electromagnetic fields on embryonic chick cell alignment and behavior

    SciTech Connect

    Thomas, J.; Wilkes, C.; Hamada, S.H. )

    1989-03-01

    All in vitro studies to date on the effects of electromagnetic fields (EMF) have utilized an amorphous substratum (i.e. glass or plastic). Earlier we reported the alignment of chick fibroblast perpendicular to an EMF in a serum-free tissue culture system. The purpose of the present experiments was to determine the effect of substratum organization on cell alignment and behavior when an EMF is applied. Fibronectin was isolated from the chicken plasma using agarose and collagen-sepharose affinity columns and its purity checked on SDS-PAGE. The fibronection was applied to glass either as an non-organized matrix or as an organized matrix parallel fibers. Chick embryonic cells require three days to align on organized fibronectin fibers. Unaligned cells (day 1 of culture) can be re-aligned by an EMF in 25 mins. However once aligned on fibronectin, these cells (day 3 of culture) require as much as 3 hours in an EMF before re-aligned can be detected. This may explain (1) why tissues require grater applied fields and longer duration of exposure to an EMF before abnormalities can be detected and (2) chick embryos are especially sensitive to EMF at earlier stages of development. We hypothesize that the resistance of fibronectin attached cells to the perturbation of EMF may be due to de novo fibronectin synthesis.

  3. Yolk absorption and embryo development of small and large eggs originating from young and old breeder hens.

    PubMed

    Nangsuay, A; Ruangpanit, Y; Meijerhof, R; Attamangkune, S

    2011-11-01

    To evaluate the effect of breeder age and egg size on yolk absorption and embryo development, a total of 4,800 Ross 308 hatching eggs were subjected to 4 treatments arranged in a 2 × 2 factorial randomized complete block design using 2 breeder ages (29 and 53 wk of age, or young and old) and 2 egg sizes (57-61 g and 66-70 g, or small and large). A significant interaction between breeder age and egg size was found for egg composition. Yolk weight increased with flock age, whereas a larger egg size resulted in higher albumen content. A significant interaction between breeder age and egg size was found for yolk-free body (YFB) weight only at d 7. Until the fourteenth day of incubation, eggs from the old flock yielded greater YFB weight than did eggs from the young flock. At hatch, chicks of both age groups had comparable wet YFB weight, chick weight, wet and dry residual yolk weight, and chick length. Dry YFB weight of chicks from the old flock was higher than that of chicks from the young flock. Compared with the small eggs, embryos and chicks of the large eggs had greater YFB weight from d 14 to hatching. At hatch, these chicks were also heavier, longer, and had higher wet and dry YFB and residual yolk weight. Yolk absorption at d 18 and at hatch of embryos and chicks of the old flock was higher than that of the young flock, both in absolute values and percentages. Rates of absolute and percentage yolk absorption through d 18 and percentage yolk absorption at hatch were higher in the small eggs than in the large eggs. It can be concluded that egg size influences chick length at hatch and embryo development when expressed in terms of total and YFB weight. Although yolk availability and rate of absorption may have influenced dry YFB weight, they did not influence hatching chick length or total and YFB weight.

  4. Limb positioning and shear flows in tetrapods

    NASA Astrophysics Data System (ADS)

    Boryskina, O. P.; Al-Kilani, A.; Fleury, V.

    2011-08-01

    There is increasing evidence that animal morphogenesis consists of a large scale tissue flow, which defines the gross characteristics of the animal body at a very early developmental stage. We have studied the vertebrate embryo cell trajectories between a moment when it is flat and formless, to a moment when the body plan is recognizable (chicken embryo days 2-3 of development). We find that a large vortex flow patterns the vertebrate bauplan, and especially the limb territories, both hindlimbs and forelimbs. In vivo velocity measurements show that the vortices are dragged by a localized shear oriented along the median axis. A simple hydrodynamic model accounts for the lenticular shape of the limb plates. On the hindlimb plate, the flow propagates in the form of a solid-body vortex on the limb plate, dragged by a Poiseuille flow along the backbone. In vivo tonometry measurements show that there exist stress gradients in the embryonic tissue, and that the flow pattern is congruent with the direction of decrease of stress magnitude.

  5. Ion Levels and Membrane Potential in Chick Heart Tissue and Cultured Cells

    PubMed Central

    McDonald, Terence F.; DeHaan, Robert L.

    1973-01-01

    Intracellular concentrations of sodium and potassium as well as resting potentials and overshoots have been determined in heart tissue from chick embryos aged 2–18 days. Intracellular potassium declined from 167 mM at day 2 to 117–119 mM at days 14–18. Intracellular sodium remained nearly constant at 30–35 mM during the same period. The mean resting potential increased from -61.8 mV at day 3 to about -80 mV at days 14–18. The mean overshoot during the same period increased from 12 to 30 mV. PNa/PK calculated from the ion data and resting potentials declined from 0.08 at day 3 to 0.01 at days 14–18. Thus, the development of embryonic chick heart during days 2–14 is characterized by a declining intracellular potassium concentration and an increasing resting potential and overshoot. Heart cells from 7- to 8-day embryos, cultured either in monolayer or reassociated into aggregates, were compared with intact tissue of the same age. The intracellular concentrations of sodium and potassium were similar in the three preparations and cultured cells responded to incubation in low potassium medium or treatment with ouabain in a manner similar to that of intact tissue. Resting potentials and overshoots were also similar in the three preparations. PMID:4683099

  6. Embryos, microscopes, and society.

    PubMed

    Maienschein, Jane

    2016-06-01

    Embryos have different meanings for different people and in different contexts. Seen under the microscope, the biological embryo starts out as one cell and then becomes a bunch of cells. Gradually these divide and differentiate to make up the embryo, which in humans becomes a fetus at eight weeks, and then eventually a baby. At least, that happens in those cases that carry through normally and successfully. Yet a popular public perception imagines the embryo as already a little person in the very earliest stages of development, as if it were predictably to become an adult. In actuality, cells can combine, pull apart, and recombine in a variety of ways and still produce embryos, whereas most embryos never develop into adults at all. Biological embryos and popular imaginations of embryos diverge. This paper looks at some of the historical reasons for and social implications of that divergence.

  7. Mechanical origins of rightward torsion in early chick brain development

    NASA Astrophysics Data System (ADS)

    Chen, Zi; Guo, Qiaohang; Dai, Eric; Taber, Larry

    2015-03-01

    During early development, the neural tube of the chick embryo undergoes a combination of progressive ventral bending and rightward torsion. This torsional deformation is one of the major organ-level left-right asymmetry events in development. Previous studies suggested that bending is mainly due to differential growth, however, the mechanism for torsion remains poorly understood. Since the heart almost always loops rightwards that the brain twists, researchers have speculated that heart looping affects the direction of brain torsion. However, direct evidence is lacking, nor is the mechanical origin of such torsion understood. In our study, experimental perturbations show that the bending and torsional deformations in the brain are coupled and that the vitelline membrane applies an external load necessary for torsion to occur. Moreover, the asymmetry of the looping heart gives rise to the chirality of the twisted brain. A computational model and a 3D printed physical model are employed to help interpret these findings. Our work clarifies the mechanical origins of brain torsion and the associated left-right asymmetry, and further reveals that the asymmetric development in one organ can induce the asymmetry of another developing organ through mechanics, reminiscent of D'Arcy Thompson's view of biological form as ``diagram of forces''. Z.C. is supported by the Society in Science - Branco Weiss fellowship, administered by ETH Zurich. L.A.T acknowledges the support from NIH Grants R01 GM075200 and R01 NS070918.

  8. Production of somatic chimera chicks by injection of bone marrow cells into recipient blastoderms.

    PubMed

    Heo, Young Tae; Lee, Sung Ho; Kim, Teoan; Kim, Nam Hyung; Lee, Hoon Taek

    2012-01-01

    Several types of cells, including blastoderm cells, primordial germ cells, and embryonic germ cells were injected into early-stage recipient embryos to produce chimera avians and to gain insights into cell development. However, a limited number of studies of avian adult stem cells have also been conducted. This study is, to the best of our knowledge, the first to evaluate chicken bone marrow cells' (chBMC) ability to differentiate into multiple cell lineages and capability to generate chimera chicks. We induced random differentiation of chBMCs in vitro and injected immunologically selected pluripotent cells in chBMCs into the blastoderms of recipient eggs. The multipotency of BMCs from the barred Plymouth rock (BPR) was confirmed via AP staining, RT-PCR, immunocytochemistry, and FACS using specific markers, such as Oct-4 and SSEA-1, 3 and 4. Isolated chBMCs were found to be able to induce in vitro differentiation to multiple cell lineages. Approximately 5,000 chBMCs were injected into the blastoderms of white leghorn (WL) recipients and proved able to contribute to the generation of somatic chimera chicks with a frequency of 2.7% (2 of 73). Confirmation of chimerism in hatched chicks was achieved via PCR analysis using D-loop-specific primers of BPR and WL. Our study demonstrated the successful production of chimera chicks using chBMC. Therefore, we propose that the use of adult chBMCs may constitute a new possible approach to the production of chimera poultry, and may provide helpful studies in avian developmental biology.

  9. Arginine requirement of starting broiler chicks.

    PubMed

    Cuca, M; Jensen, L S

    1990-08-01

    Three experiments were conducted to estimate the arginine requirement of male broiler chicks from 0 to 3 wk of age. The experiments were conducted in battery brooders with wires floors, and the birds received water and feed ad libitum. In the first experiment, chicks were fed a diet based on corn, soybean meal, casein, and corn-gluten meal containing 3,200 kcal ME per kg and either 20 or 23% crude protein. Regression analysis indicated an arginine requirement of 1.22% for maximum growth rate and feed efficiency with the 20% protein diet. For chicks fed the 23% protein diet, neither growth rate nor feed efficiency was significantly different among the diets containing arginine ranging from 1.13 to 1.43%. In the second experiment, a basal diet was used containing 17.5% casein and 22.5% protein with arginine ranging from 1.03 to 1.43%. An arginine requirement of 1.18% for maximum body weight gain was estimated by regression analysis, but no significant response to arginine above the basal level was observed for feed efficiency. Performance of chicks fed the basal diet was somewhat reduced because of a difficulty with adherence of feed to the beaks. In a third experiment, three basal diets containing 21, 22, or 23% protein were formulated from practical ingredients without use of casein. The requirement for maximum growth rate and feed efficiency was estimated to be 1.24 to 1.28% for the three diets. The results of these investigations indicate that the arginine requirement for starting chicks suggested by the National Research Council in 1984 of 1.44% in diets containing 3,200 kcal ME per kg is too high for practical diets. The data presented here support an arginine requirement of 1.25%. PMID:2235851

  10. The adrenocortical response of tufted puffin chicks to nutritional deficits

    USGS Publications Warehouse

    Kitaysky, A.S.; Romano, Marc D.; Piatt, J.F.; Wingfield, J.C.; Kikuchi, M.

    2005-01-01

    In several seabirds, nutritional state of a nest-bound chick is negatively correlated with the activity of its hypothalamus-pituitary-adrenal (HPA) axis. Increased corticosterone (cort) secretion has been shown to facilitate changes in behavior that allow hungry chicks to obtain more food from parents. However, if parents are not willing/able to buffer their young from temporary food shortages, increased cort secretion could be detrimental to undernourished chicks. In a system where parents are insensitive to chick demands, low benefits and high costs of activation of the HPA-axis in hungry chicks should lead to a disassociation of the nutritional state of the young and the activity of its HPA-axis. We tested this novel hypothesis for the tufted puffin (Fratercula cirrhata), a seabird with intermittent provisioning of a nest-bound semi-precocial chick. We examined the HPA-axis activity of captive chicks exposed to the following: (1) a short-term (24 h) food deprivation; and (2) an array of prolonged (3 weeks) restrictions in feeding regimens. We found that in response to a short-term food deprivation chicks decreased baseline levels of cort and thyroid hormones. In response to prolonged restrictions, food-limited chicks exhibited signs of nutritional deficit: they had lower body mass, endogenous lipid reserves, and thyroid hormone titers compared to chicks fed ad libitum. However, baseline and maximum acute stress-induced levels of cort were also lower in food-restricted chicks compared to those of chicks fed ad libitum. These results support a major prediction of the study hypothesis that puffin chicks suppress HPA-axis activity in response to short- and long-term nutritional deficits. This physiological adaptation may allow a chick to extend its development in the nest, while eluding detrimental effects of chronic cort elevation. 

  11. Culture systems: embryo density.

    PubMed

    Reed, Michael L

    2012-01-01

    Embryo density is defined as the embryo-to-volume ratio achieved during in vitro culture; in other words, it is the number of embryos in a defined volume of culture medium. The same density can be achieved by manipulating either the number of embryos in a given volume of medium, or manipulating the volume of the medium for a given number of embryos: for example, a microdrop with five embryos in a 50 μl volume under oil has the same embryo-to-volume ratio (1:10 μl) as a microdrop with one embryo in a 10 μl volume under oil (1:10 μl). Increased embryo density can improve mammalian embryo development in vitro; however, the mechanism(s) responsible for this effect may be different with respect to which method is used to increase embryo density.Standard, flat sterile plastic petri dishes are the most common, traditional platform for embryo culture. Microdrops under a mineral oil overlay can be prepared to control embryo density, but it is critical that dish preparation is consistent, where appropriate techniques are applied to prevent microdrop dehydration during preparation, and results of any data collection are reliable, and repeatable. There are newer dishes available from several manufacturers that are specifically designed for embryo culture; most are readily available for use with human embryos. The concept behind these newer dishes relies on fabrication of conical and smaller volume wells into the dish design, so that embryos rest at the lowest point in the wells, and where putative embryotrophic factors may concentrate.Embryo density is not usually considered by the embryologist as a technique in and of itself; rather, the decision to culture embryos in groups or individually is protocol-driven, and is based more on convenience or the need to collect data on individual embryos. Embryo density can be controlled, and as such, it can be utilized as a simple, yet effective tool to improve in vitro development of human embryos. PMID:22829380

  12. Cannabinoid receptor 1 signaling in embryo neurodevelopment.

    PubMed

    Psychoyos, Delphine; Vinod, K Yaragudri; Cao, Jin; Xie, Shan; Hyson, Richard L; Wlodarczyk, Bogdan; He, Weimin; Cooper, Thomas B; Hungund, Basalingappa L; Finnell, Richard H

    2012-04-01

    In utero exposure to tetrahydrocannabinol, the psychoactive component of marijuana, is associated with an increased risk for neurodevelopmental defects in the offspring by interfering with the functioning of the endocannabinoid (eCB) system. At the present time, it is not clearly known whether the eCB system is present before neurogenesis. Using an array of biochemical techniques, we analyzed the levels of CB1 receptors, eCBs (AEA and 2-AG), and the enzymes (NAPE-PLD, DAGLα, DAGLβ, MAGL, and FAAH) involved in the metabolism of the eCBs in chick and mouse models during development. The findings demonstrate the presence of eCB system in early embryo before neurogenesis. The eCB system might play a critical role in early embryogenesis and there might be adverse developmental consequences of in utero exposure to marijuana and other drugs of abuse during this period.

  13. Efficacy of using radio transmitters to monitor least tern chicks

    USGS Publications Warehouse

    Whittier, Joanna B.; Leslie, David M.

    2005-01-01

    Little is known about Least Tern (Sterna antillarum) chicks from the time they leave the nest until fledging because they are highly mobile and cryptically colored. We evaluated the efficacy of using radiotelemetry to monitor Interior Least Tern (S. a. athalassos) chicks at Salt Plains National Wildlife Refuge, Oklahoma. In 1999, we attached radio transmitters to 26 Least Tern chicks and tracked them for 2-17 days. No adults abandoned their chicks after transmitters were attached. Transmitters did not appear to alter growth rates of transmittered chicks (P = 0.36) or prevent feather growth, although dermal irritation was observed on one chick. However, without frequent reattachment, transmitters generally did not remain on chicks <1 week old for more than 2 days because of feather growth and transmitter removal, presumably by adult terns. Although the presence of transmitters did not adversely affect Least Tern chicks, future assessments should investigate nonintrusive methods to improve retention of transmitters on young chicks and reduce the number of times that chicks need to be handled.

  14. Morpholinos: studying gene function in the chick

    PubMed Central

    Norris, Anneliese; Streit, Andrea

    2014-01-01

    The use of morpholinos for perturbing gene function in the chick, Gallus gallus, has led to many important discoveries in developmental biology. This technology makes use of in vivo electroporation, which allows gain and loss of function in a temporally, and spatially controlled manner. Using this method, morpholinos can be transfected into embryonic tissues from early to late developmental stages. In this article, we describe the methods currently used in our laboratory to knock down gene function using morpholinos in vivo. We also detail how morpholinos are used to provide consistency of the results, and describe two protocols to visualise the morpholino after electroporation. In addition, we provide guidance on avoiding potential pitfalls, and suggestions for troubleshooting solutions. These revised techniques provide a practical starting point for investigating gene function in the chick. PMID:24184187

  15. Characterization of the finch embryo supports evolutionary conservation of the naive stage of development in amniotes.

    PubMed

    Mak, Siu-Shan; Alev, Cantas; Nagai, Hiroki; Wrabel, Anna; Matsuoka, Yoko; Honda, Akira; Sheng, Guojun; Ladher, Raj K

    2015-09-11

    Innate pluripotency of mouse embryos transits from naive to primed state as the inner cell mass differentiates into epiblast. In vitro, their counterparts are embryonic (ESCs) and epiblast stem cells (EpiSCs), respectively. Activation of the FGF signaling cascade results in mouse ESCs differentiating into mEpiSCs, indicative of its requirement in the shift between these states. However, only mouse ESCs correspond to the naive state; ESCs from other mammals and from chick show primed state characteristics. Thus, the significance of the naive state is unclear. In this study, we use zebra finch as a model for comparative ESC studies. The finch blastoderm has mESC-like properties, while chick blastoderm exhibits EpiSC features. In the absence of FGF signaling, finch cells retained expression of pluripotent markers, which were lost in cells from chick or aged finch epiblasts. Our data suggest that the naive state of pluripotency is evolutionarily conserved among amniotes.

  16. In ovo electroporation in embryonic chick retina.

    PubMed

    Islam, Mohammed M; Doh, Sung Tae; Cai, Li

    2012-02-05

    Chicken embryonic retina is an excellent tool to study retinal development in higher vertebrates. Because of large size and external development, it is comparatively very easy to manipulate the chick embryonic retina using recombinant DNA/RNA technology. Electroporation of DNA/RNA constructs into the embryonic retina have a great advantage to study gene regulation in retinal stem/progenitor cells during retinal development. Different type of assays such as reporter gene assay, gene over-expression, gene knock down (shRNA) etc. can be performed using the electroporation technique. This video demonstrates targeted retinal injection and in ovo electroporation into the embryonic chick retina at the Hamburger and Hamilton stage 22-23, which is about embryonic day 4 (E4). Here we show a rapid and convenient in ovo electroporation technique whereby a plasmid DNA that expresses green fluorescent protein (GFP) as a marker is directly delivered into the chick embryonic subretinal space and followed by electric pulses to facilitate DNA uptake by retinal stem/progenitor cells. The new method of retinal injection and electroporation at E4 allows the visualization of all retinal cell types, including the late-born neurons(1), which has been difficult with the conventional method of injection and electroporation at E1.5(2).

  17. HINTW, a W-chromosome HINT gene in chick, is expressed ubiquitously and is a robust female cell marker applicable in intraspecific chimera studies.

    PubMed

    Nagai, Hiroki; Sezaki, Maiko; Bertocchini, Federica; Fukuda, Kimiko; Sheng, Guojun

    2014-05-01

    Grafting and transplantation experiments in embryology require proper distinction between host and donor tissues. For the avian model this has traditionally been achieved by using two closely related species (e.g., chick and quail) followed by species-specific antibody staining. Here, we show that an in situ hybridization probe against the HINTW gene is a robust and reliable marker for female-derived chicken cells. At all pre-circulation stages tested, all cells in female embryos, independently confirmed by PCR analysis, were strongly positive for HINTW, whereas all male embryos were negative. This probe is broadly applicable in intra-specific chick/chick chimera studies, and as a proof of principle, we utilized this probe to detect female cells in three experimental settings: (1) to mark female donor cells in a node transplantation assay; (2) to distinguish female cells in male/female twins generated by the Cornish pasty culture; and (3) to detect female half of the embryo in artificially generated bilateral gynandromorphs. A rapid, PCR based pre-screening step increases the efficiency of obtaining desired donor/host sex combination from 25% to 100%. For most avian chimera studies, this female-specific in situ probe is a low cost alternative to the commonly used QCPN antibody and to ubiquitous-GFP chicken strains which are not widely available to the research community.

  18. Developmental imaging: the avian embryo hatches to the challenge.

    PubMed

    Kulesa, Paul M; McKinney, Mary C; McLennan, Rebecca

    2013-06-01

    The avian embryo provides a multifaceted model to study developmental mechanisms because of its accessibility to microsurgery, fluorescence cell labeling, in vivo imaging, and molecular manipulation. Early two-dimensional planar growth of the avian embryo mimics human development and provides unique access to complex cell migration patterns using light microscopy. Later developmental events continue to permit access to both light and other imaging modalities, making the avian embryo an excellent model for developmental imaging. For example, significant insights into cell and tissue behaviors within the primitive streak, craniofacial region, and cardiovascular and peripheral nervous systems have come from avian embryo studies. In this review, we provide an update to recent advances in embryo and tissue slice culture and imaging, fluorescence cell labeling, and gene profiling. We focus on how technical advances in the chick and quail provide a clearer understanding of how embryonic cell dynamics are beautifully choreographed in space and time to sculpt cells into functioning structures. We summarize how these technical advances help us to better understand basic developmental mechanisms that may lead to clinical research into human birth defects and tissue repair.

  19. Dioxin contamination and growth and development in great blue heron embryos

    SciTech Connect

    Hart, L.E.; Cheng, K.M.; Whitehead, P.E.; Shah, R.M.; Lewis, R.J.; Ruschkowski, S.R.; Blair, R.W.; Bennett, D.C.; Bandiera, S.M.; Norstrom, R.J. )

    1991-03-01

    A great blue heron colony located near a pulp mill in British Columbia failed to fledge young in 1987, with a concurrent sharp increase in polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) levels in their eggs. In 1988 we tested the hypothesis that the PCDD and PCDF contamination caused reproductive failure by increasing mortality of the heron embryos in ovo. Pairs of great blue heron eggs were collected from three British Columbia colonies with low, intermediate, and high levels of dioxin contamination: Nicomekl, Vancouver, and Crofton, respectively. One egg of each pair was incubated under laboratory conditions at the University of British Columbia (UBC) while the other egg was analyzed for PCDDs and PCDFs. All incubated eggs were fertile. All eggs from the Nicomekl colony hatched, while 13 of 14 eggs from Vancouver and 12 of 13 eggs from Crofton hatched. Subcutaneous edema was observed in 4 of 12 chicks from Crofton and 2 of 13 chicks from Vancouver. No edema was seen in the chicks from Nicomekl. There was a small, but significant, negative regression of plasma calcium concentration, yolk-free body weight, tibia length, wet, dry, and ash weight, beak length, and kidney and stomach weight of the hatched chicks on the tetrachlorodibenzo-p-dioxin (TCDD) level of the paired eggs. Fewer down follicles were present on the heads of TCDD-contaminated chicks. Hence while dioxins did not cause mortality of the heron embryos in ovo, the depression of growth and the presence of edema are suggestive that dioxins at the levels found in the environment have an adverse effect on the development of great blue heron embryos.

  20. LIMB Demonstration Project Extension

    SciTech Connect

    Not Available

    1989-11-15

    The basic goal of the Limestone Injection Mitigation Burner (LIMB) demonstration is to extend LIMB technology development to a full- scale application on a representative wall-fired utility boiler. The successful retrofit of LIMB to an existing boiler is expected to demonstrate that (a) reductions of 50 percent or greater in SO{sub x} and NO{sub x} emissions can be achieved at a fraction of the cost of add-on FGD systems, (b) boiler reliability, operability, and steam production can be maintained at levels existing prior to LIMB retrofit, and (c) technical difficulties attributable to LIMB operation, such as additional slagging and fouling, changes in ash disposal requirements, and an increased particulate load, can be resolved in a cost-effective manner. The primary fuel to be used will be an Ohio bituminous coal having a nominal sulfur content of 3 percent or greater.

  1. Experimental colonization of broiler chicks with Campylobacter jejuni.

    PubMed Central

    Shanker, S.; Lee, A.; Sorrell, T. C.

    1988-01-01

    Minimal colonization inocula for two broiler strains of Campylobacter jejuni were determined in broiler chicks aged 2-3 days and 2 weeks. Individually housed chicks were exposed to a single oral or cloacal challenge. Diarrhoeal symptoms were absent in all 380 chicks included in the study. Chick susceptibility to the two C. jejuni strains varied. Colonization was effected by less than 10(2)-10(4) colony forming units (c.f.u.) via cloacal challenge and 10(4)-10(6) c.f.u. via the oral route. Colonization inocula for 2- to 3-day and 2-week-old chicks were similar. Treatment of 1-day-old chicks with fresh adult caecal flora or an anaerobic broth culture of adult caecal flora did not inhibit colonization after challenge with low-dose C. jejuni. Susceptible chicks were colonized rapidly. C. jejuni was detected in 167 of 189 (88%) colonized chicks within 3 days of challenge and persisted during the 2-week monitoring period. Our data suggest that colonization of broiler chicks with C. jejuni is effected more easily by the cloacal than the oral route and is independent of age. PMID:3338504

  2. The avian embryo as a model in developmental studies: chimeras and in vitro clonal analysis.

    PubMed

    Dupin, E; Ziller, C; Le Douarin, N M

    1998-01-01

    The avian embryo is a model in which techniques of experimental embryology and cellular and molecular biology can converge to address fundamental questions of development biology. The first part of the chapter describes two examples of transplantation and cell labeling experiments performed in ovo. Thanks to the distinctive histologic and immunocytochemical characteristics of quail and chick cells, the migration and development of definite cells are followed in suitably constructed chimeric quail-chick embryos. Isotopic transplantations of neural tube portions between quail and chick, combined with in situ hybridization with a nucleic probe specific for a quail oligodendrocyte marker, allowed study of the origin and migration of oligodendroblasts in the spinal cord. Heterotopic transplantations of rhombomeres were performed to establish the degree of plasticity of these segments of the hindbrain regarding Hox gene expression, which was revealed by labeling with chick-specific nucleic probes. The second part describes in vitro cell cloning experiments devised to investigate cell lineage segregation and diversification during development of the NC. An original cloning procedure and optimal culture conditions permitted analysis of the developmental potentials of individual NC cells taken at definite migration stages. The results revealed a striking heterogeneity of the crest cell population, which appeared to be composed of precursors at different states of determination. Clonal cultures also provide a means to identify subsets of cells that are the target of environmental factors and to understand how extrinsic signals influence the development of responsive cells.

  3. Oxygenated drinking water enhances immune activity in broiler chicks and increases survivability against Salmonella Gallinarum in experimentally infected broiler chicks.

    PubMed

    Jung, Bock-Gie; Lee, Jin-A; Nam, Kyoung-Woo; Lee, Bong-Joo

    2012-03-01

    It has been suggested that drinking oxygenated water may improve oxygen availability, which may increase vitality and improving immune activity. The present study evaluated the immune enhancing effects of oxygenated drinking water in broiler chicks and demonstrated the protective efficacy of oxygenated drinking water against Salmonella Gallinarum in experimentally infected broiler chicks. Continuous drinking of oxygenated water markedly increased serum lysozyme activity, peripheral blood mononuclear cell proliferation and the CD4(+)/CD8(+) splenocyte ratio in broiler chicks. In the chicks experimentally infected with S. Gallinarum, oxygenated drinking water alleviated symptoms and increased survival. These findings suggest that oxygenated drinking water enhances immune activity in broiler chicks, and increases survivability against S. Gallinarum in experimentally infected broiler chicks.

  4. Effects of colchicine on the shape of chick neuroepithelial cells during neurulation.

    PubMed

    Fernandez, J G; de Paz, P; Chamorro, C A

    1987-11-01

    We have analyzed the effects of colchicine on the cell shapes in chick neuroepithelium. Cell shapes were ascertained by the position of the nucleus in plastic serial sections. We tested three colchicine doses (5 X 10(-5) M, 5 X 10(-6) M, and 5 X 10(-7) M) by two experimental treatments (in ovo and in vitro). Colchicine treatment in vitro is always effective in depolymerizing microtubules of neuroepithelial cells and reduces the percentages of wedge-shaped cells in the median area of neuroepithelium. The same effect can be observed when the embryos are treated with 5 X 10(-5) M or 5 X 10(-6) M colchicine in ovo. A concentration of colchicine of 5 X 10(-7) M in ovo cannot disrupt microtubules in stage 8 and stage 10 embryos, and the percentage of wedge-shaped cells is the same as that of the untreated cells. In stage 6 embryos this colchicine dose effects the microtubules and the percentages of wedge-shaped cells. These facts are interpreted in respect to variations in microtubular resistance to microtubular-disrupting agents that are shown by the neuroepithelial cells from different developmental stages.

  5. MATURATION OF FIRING PATTERN IN CHICK VESTIBULAR NUCLEUS NEURONS

    PubMed Central

    SHAO, M.; HIRSCH, J. C.; PEUSNER, K. D.

    2007-01-01

    The principal cells of the chick tangential nucleus are vestibular nucleus neurons participating in the vestibuloocular and vestibulocollic reflexes. In birds and mammals, spontaneous and stimulus-evoked firing of action potentials is essential for vestibular nucleus neurons to generate mature vestibular reflex activity. The emergence of spike-firing pattern and the underlying ion channels were studied in morphologically-identified principal cells using whole-cell patch-clamp recordings from brain slices of late-term embryos (embryonic day 16) and hatchling chickens (hatching day 1 and hatching day 5). Spontaneous spike activity emerged around the perinatal period, since at embryonic day 16 none of the principal cells generated spontaneous action potentials. However, at hatching day 1, 50% of the cells fired spontaneously (range, 3 to 32 spikes/s), which depended on synaptic transmission in most cells. By hatching day 5, 80% of the principal cells could fire action potentials spontaneously (range, 5 to 80 spikes/s), and this activity was independent of synaptic transmission and showed faster kinetics than at hatching day 1. Repetitive firing in response to depolarizing pulses appeared in the principal cells starting around embryonic day 16, when < 20% of the neurons fired repetitively. However, almost 90% of the principal cells exhibited repetitive firing on depolarization at hatching day 1, and 100% by hatching day 5. From embryonic day 16 to hatching day 5, the gain for evoked spike firing increased almost 10-fold. At hatching day 5, a persistent sodium channel was essential for the generation of spontaneous spike activity, while a small conductance, calcium-dependent potassium current modulated both the spontaneous and evoked spike firing activity. Altogether, these in vitro studies showed that during the perinatal period, the principal cells switched from displaying no spontaneous spike activity at resting membrane potential and generating one spike on

  6. Oxygen uptake during early cardiogenesis of the chick.

    PubMed

    Raddatz, E; Servin, M; Kucera, P

    1992-04-01

    Oxidative metabolism of the isolated embryonic heart of the chick has been determined using a spectrophotometric technique allowing global as well as localized micromeasurements of the O2 uptake. Entire hearts, excised from embryos of 10 somites (primordia fused, stage 10 HH) and 40 somites (S shaped, stage 20 HH) were placed in a special chamber under controlled metabolic conditions where they continued to beat spontaneously and regularly. During the 32 h of development, the O2 consumption of the whole heart increased from 0.9 +/- 0.1 to 5.3 +/- 0.8 nmol O2/h. These values corrected for protein content were, however, comparable (0.45 nmol O2.h-1.micrograms-1). At stage 10-12, the O2 uptake varied along the cardiac tube (from 0.74 to 1.0 nmol O2.h-1.mm-2). From stage 10 to 20, the O2 uptake per unit area of ventricle wall increased from 0.7 +/- 0.2 to 1.8 +/- 0.2 nmol O2.h-1.mm-2, and the O2 uptake per myocardial volume during one cardiac cycle varied from 7 to 2.5 nmol O2/cm3. These results indicate that, despite an intense morphogenesis, the cardiac tissue has a rather low and stable oxidative metabolism, although the O2 requirement of the whole heart increases significantly. Moreover, the normalized suprabasal aerobic energy expenditure decreases throughout early cardiogenesis. The functional integrity of the isolated embryonic heart combined with the experimental possibilities of the microtechnique make the preparation appropriate for studying the changes in cardiac metabolism during development.

  7. Patterning of the chick forebrain anlage by the prechordal plate.

    PubMed

    Pera, E M; Kessel, M

    1997-10-01

    We analysed the role of the prechordal plate in forebrain development of chick embryos in vivo. After transplantation to uncommitted ectoderm a prechordal plate induces an ectopic, dorsoventrally patterned, forebrain-like vesicle. Grafting laterally under the anterior neural plate causes ventralization of the lateral side of the forebrain, as indicated by a second expression domain of the homeobox gene NKX2.1. Such a lateral ventralization cannot be induced by the secreted factor Sonic Hedgehog alone, as this is only able to distort the ventral forebrain medially. Removal of the prechordal plate does not reduce the rostrocaudal extent of the anterior neural tube, but leads to significant narrowing and cyclopia. Excision of the head process results in the caudal expansion of the NKX2.1 expression in the ventral part of the anterior neural tube, while PAX6 expression in the dorsal part remains unchanged. We suggest that there are three essential steps in early forebrain patterning, which culminate in the ventralization of the forebrain. First, anterior neuralization occurs at the primitive streak stage, when BMP-4-antagonizing factors emanate from the node and spread in a planar fashion to induce anterior neural ectoderm. Second, the anterior translocation of organizer-derived cells shifts the source of neuralizing factors anteriorly, where the relative concentration of BMP-4-antagonists is thus elevated, and the medial part of the prospective forebrain becomes competent to respond to ventralizing factors. Third, the forebrain anlage is ventralized by signals including Sonic Hedgehog, thereby creating a new identity, the prospective hypothalamus, which splits the eye anlage into two lateral domains.

  8. LIMB demonstration project extension

    SciTech Connect

    Not Available

    1990-09-21

    The purpose of the DOE limestone injection multistage burner (LIMB) Demonstration Project Extension is to extend the data base on LIMB technology and to expand DOE's list of Clean Coal Technologies by demonstrating the Coolside process as part of the project. The main objectives of this project are: to demonstrate the general applicability of LIMB technology by testing 3 coals and 4 sorbents (total of 12 coal/sorbent combinations) at the Ohio Edison Edgewater plant; and to demonstrate that Coolside is a viable technology for improving precipitator performance and reducing sulfur dioxide emissions while acceptable operability is maintained. Progress is reported. 3 figs.

  9. Chlormequat chloride retards rat embryo growth in vitro.

    PubMed

    Xiagedeer, Bayindala; Wu, Shuang; Liu, Yingjuan; Hao, Weidong

    2016-08-01

    Chlormequat chloride is the most widely used plant growth regulator in agriculture to promote sturdier growth of grain crops by avoidance of lodging. Therefore, human exposure to chlormequat chloride is very common, but its developmental toxicity has not been studied. Thus, we investigated the developmental toxicity of chlormequat chloride by applying rat whole embryo culture (WEC) model, limb bud micromass culture and 3T3 fibroblast cytotoxicity test. Chlormequat chloride at 150μg/ml (0.93mM) retarded the rat embryo growth without causing significant morphological malformations and at 500μg/ml (3.1mM) caused both retardation and morphological malformation of the embryos. However, the proliferation and differentiation of limb bud cells were not affected by chlormequat chloride at as high as up to 1000μg/ml (6.2mM) applied. This concentration of chlormequat chloride did not affect the cell viability as examined by 3T3 fibroblast cytotoxicity test either, suggesting that cellular toxicity may not play a role in chlormequat induced inhibition of rat embryo growth. Collectively, our results demonstrated that chlormequat chloride may affect embryo growth and development without inhibiting cell viability.

  10. Out on a Limb: Investigating the Anatomy of Tree Limbs

    ERIC Educational Resources Information Center

    Shaw, Edward L.

    2008-01-01

    The author presents several upper elementary science activities involving tree limbs that were collected after severe weather conditions. The activities involved 3rd-grade students arranging tree limb pieces in the correct order from the trunk to the tip of the limb, measuring the pieces, determining the age of a tree limb by its rings,…

  11. Attenuated sensing of SHH by Ptch1 underlies evolution of bovine limbs.

    PubMed

    Lopez-Rios, Javier; Duchesne, Amandine; Speziale, Dario; Andrey, Guillaume; Peterson, Kevin A; Germann, Philipp; Unal, Erkan; Liu, Jing; Floriot, Sandrine; Barbey, Sarah; Gallard, Yves; Müller-Gerbl, Magdalena; Courtney, Andrew D; Klopp, Christophe; Rodriguez, Sabrina; Ivanek, Robert; Beisel, Christian; Wicking, Carol; Iber, Dagmar; Robert, Benoit; McMahon, Andrew P; Duboule, Denis; Zeller, Rolf

    2014-07-01

    The large spectrum of limb morphologies reflects the wide evolutionary diversification of the basic pentadactyl pattern in tetrapods. In even-toed ungulates (artiodactyls, including cattle), limbs are adapted for running as a consequence of progressive reduction of their distal skeleton to symmetrical and elongated middle digits with hoofed phalanges. Here we analyse bovine embryos to establish that polarized gene expression is progressively lost during limb development in comparison to the mouse. Notably, the transcriptional upregulation of the Ptch1 gene, which encodes a Sonic hedgehog (SHH) receptor, is disrupted specifically in the bovine limb bud mesenchyme. This is due to evolutionary alteration of a Ptch1 cis-regulatory module, which no longer responds to graded SHH signalling during bovine handplate development. Our study provides a molecular explanation for the loss of digit asymmetry in bovine limb buds and suggests that modifications affecting the Ptch1 cis-regulatory landscape have contributed to evolutionary diversification of artiodactyl limbs. PMID:24990743

  12. Micromanipulation of mammalian embryos.

    PubMed

    Sugawara, S

    1988-11-01

    Micromanipulation of embryos provide a new and valuable biological tool for animal agriculture and medical fields. Current techniques for embryo manipulation are in practice but some of techniques is still way off for application. The present status in new biotechnology applying to animal science and medicine is reviewed and its future is also discussed. PMID:3072425

  13. Mouse Embryo Compaction.

    PubMed

    White, M D; Bissiere, S; Alvarez, Y D; Plachta, N

    2016-01-01

    Compaction is a critical first morphological event in the preimplantation development of the mammalian embryo. Characterized by the transformation of the embryo from a loose cluster of spherical cells into a tightly packed mass, compaction is a key step in the establishment of the first tissue-like structures of the embryo. Although early investigation of the mechanisms driving compaction implicated changes in cell-cell adhesion, recent work has identified essential roles for cortical tension and a compaction-specific class of filopodia. During the transition from 8 to 16 cells, as the embryo is compacting, it must also make fundamental decisions regarding cell position, polarity, and fate. Understanding how these and other processes are integrated with compaction requires further investigation. Emerging imaging-based techniques that enable quantitative analysis from the level of cell-cell interactions down to the level of individual regulatory molecules will provide a greater understanding of how compaction shapes the early mammalian embryo. PMID:27475854

  14. Upper limb prostheses.

    PubMed

    Bogucki, A

    2001-04-30

    This article discusses the technical and medical difficulties involved in managing prostheses of the upper limb. The level of amputation governs the type of prosthesis construction chosen, but does not affect emotional acceptance. The factors determining therapeutic success include the quality of the stump, the skill involved in prosthetic socket fabrication, and the proper selection of modular components, as well as good rehabilitation and professional care for the patient with amputated upper limb. PMID:17987000

  15. Gamma irradiation treatment of cereal grains for chick diets

    SciTech Connect

    Campbell, G.L.; Classen, H.L.; Ballance, G.M.

    1986-04-01

    Wheat (W), triticale (T), hulled barley (HB), hull-less barley (HLB), hulled oats (HO), and hull-less oats (HLO) were gamma irradiated (/sup 60/Co) at 0, 3, 6 and 9 Mrad to study the effect of irradiation on the nutritional value of cereal grains for chicks. A significant curvilinear relationship between radiation dose and 3-wk body weight of chicks fed irradiated cereals was noted for T, HB, HLB, HO and HLO. Chicks fed W or T showed no effect or lower body weight, respectively, while body weights of chicks fed barley or oat samples were higher with irradiation. The improvement tended to be maximal at the 6 Mrad level. Irradiation significantly improved the gain-to-feed ratio for chicks fed either HO or HLO. Apparent fat retention and tibia ash were higher in chicks fed irradiated HLO than in those fed untreated HLO. In a second experiment chick body weight, apparent amino acid and fat retention, tibia ash, and gain-to-feed ratios were lower in chicks fed autoclaved (121 degrees C for 20 min) barley than in those fed untreated barley. Irradiation (6 Mrad) subsequent to autoclaving barley samples eliminated these effects. Irradiation appears to benefit cereals containing soluble or mucilagenous fiber types as typified by beta-glucan of barley and oats. These fibers appear prone to irradiation-induced depolymerization, as suggested by increased beta-glucan solubility and reduced extract viscosity for irradiated barley and oat samples.

  16. Assessing Thermal Comfort of Broiler Chicks During Brooding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Proper management of the thermal environment during brooding is essential to performance in broilers. Brooding programs used in the broiler industry are prescriptive, but little information exists about thermal comfort in chicks. Identifying thermal conditions that chicks prefer would allow for be...

  17. Stimulation by Insulin of Cell Elongation and Microtubule Assembly in Embryonic Chick-Lens Epithelia

    PubMed Central

    Piatigorsky, Joram; Rothschild, Sonia S.; Wollberg, Miriam

    1973-01-01

    Both fetal-calf serum and insulin cause cell elongation in explanted chick-lens epithelia from 6-day-old embryos. We show that 1 μg/ml of insulin, like serum, stimulates a doubling of cell length and an assembly of longitudinally oriented microtubules; colchicine treatment inhibits this cell elongation. In contrast to serum, insulin neither promotes further lens-cell elongation nor appreciably stimulates the synthesis of bulk proteins or of delta crystallin under the present conditions. These data indicate that the early morphological events of lens fiber differentiation can be initiated by insulin in a chemically defined, serum-free medium without significant affects upon protein synthesis. Images PMID:4515617

  18. In vitro chick pre-cardiac explant tissue differentiation during spaceflight on SpaceHab-02

    NASA Technical Reports Server (NTRS)

    van Twest, J. S.; Paulsen, A.; Spooner, B. S.

    1995-01-01

    Chick precardiac tissue explants were cultured on the 8-day mission of STS-60, space shuttle Discovery. Development of in vitro cultures of precardiac chick tissue from embryo stages 5 though 8 (H-H) were initiated during orbit and were terminated after approximately fifteen hours of 37 degree C culture. Transmission electron microscopy and tritiated thymidine studies were performed postflight. No significant differences in cell proliferation were observed between flight and ground controls. Electron-microscopic studies revealed stage 8 explants were capable of differentiation during flight in a pattern which matched ground control tissues. As anticipated, stage 7 explant tissues had differentiated to a lesser extent compared to stage 8 tissues. Interestingly, stage 7 precardiac explant flight tissue differentiation was less than ground control tissue. This difference in differentiation between flight and ground cultures was enhanced in stage 6 tissues, as high levels of myofibril organization were only seen in ground controls. Other cellular components such as Golgi apparatus, junctional complexes, and mitochondria were present and appeared normal and healthy.

  19. Nitric oxide synthase expression, enzyme activity and NO production during angiogenesis in the chick chorioallantoic membrane

    PubMed Central

    Pipili-Synetos, Eva; Kritikou, Sosanna; Papadimitriou, Evangelia; Athanassiadou, Aglaia; Flordellis, C; Maragoudakis, M E

    2000-01-01

    In order to elucidate further the role of nitric oxide (NO) as an endogenous antiangiogenic mediator, mRNA expression of inducible nitric oxide synthase (iNOS), enzyme activity and production of NO were determined in the chick chorioallantoic membrane (CAM), an in vivo model of angiogenesis. In this model, maximum angiogenesis is reached between days 9–12 of chick embryo development. After that period, vascular density remains constant. Inducible NO synthase (iNOS) mRNA expression, determined by reverse transcriptase polymerase chain reaction (RT–PCR), increased from the 8th day reaching a maximum (70% increase) at days 10–11. NO synthase activity, determined as citrulline formation in the presence of calcium, also increased from day 8 reaching a maximum around day 10 (100% increase). Similar results were obtained in the absence of calcium suggesting that the NOS determined was the inducible form. Nitric oxide production, determined as nitrites, increased from day 8 reaching a maximum around day 10 (64% increase) and remaining stable at day 13. Finally, the bacterial lipopolysaccharide LPS (which activates transcriptionally iNOS), inhibited dose dependently angiogenesis in the CAM. These results in connection with previous findings from this laboratory, showing that NO inhibits angiogenesis in the CAM, suggest that increases in iNOS expression, enzyme activity and NO production closely parallel the progression of angiogenesis in the CAM, thus providing an endogenous brake to control this process. PMID:10694222

  20. Twist1 activity thresholds define multiple functions in limb development

    PubMed Central

    Krawchuk, Dayana; Weiner, Shoshana J.; Chen, You-Tzung; Lu, Benson; Costantini, Frank; Behringer, Richard R.; Laufer, Ed

    2010-01-01

    Summary The basic helix-loop-helix transcription factor Twist1 is essential for normal limb development. Twist1−/− embryos die at midgestation. However, studies on early limb buds found that Twist1−/− mutant limb mesenchyme has an impaired response to FGF signaling from the apical ectodermal ridge, which disrupts the feedback loop between the mesenchyme and AER, and reduces and shifts anteriorly Shh expression in the zone of polarizing activity. We have combined Twist1 null, hypomorph and conditional alleles to generate a Twist1 allelic series that survives to birth. As Twist1 activity is reduced, limb skeletal defects progress from preaxial polydactyly to girdle reduction combined with hypoplasia, aplasia or mirror symmetry of all limb segments. With reduced Twist1 activity there is striking and progressive upregulation of ectopic Shh expression in the anterior of the limb, combined with an anterior shift in the posterior Shh domain, which is expressed at normal intensity, and loss of the posterior AER. Consequently limb outgrowth is initially impaired, before an ectopic anterior Shh domain expands the AER, promoting additional growth and repatterning. Reducing the dosage of FGF targets of the Etv gene family, which are known repressors of Shh expression in the anterior limb mesenchyme, strongly enhances the anterior skeletal phenotype. Conversely this and other phenotypes are suppressed by reducing the dosage of the Twist1 antagonist Hand2. Our data support a model whereby multiple Twist1 activity thresholds contribute to early limb bud patterning, and suggest how particular combinations of skeletal defects result from differing amounts of Twist1 activity. PMID:20732316

  1. Research notes: passive integrated transponder tags as markers for chicks.

    PubMed

    Jamison, B E; Beyer, R S; Robel, R J; Pontius, J S

    2000-07-01

    Passive integrated transponder (PIT) tags have been used to mark a variety of organisms and have potential for marking poultry chicks. We examined the effects of PIT tags subcutaneously implanted in 3- and 7-d-old Leghorn chicks and found no significant differences over 40 d in survival or rate of daily body mass gain among tagged chicks and controls. The PIT-tagged birds were not more susceptible to pecking by other chicks than controls. No birds died, but 1 of 20 chicks lost its tag during the study. We believe that PIT tags provide a viable technique for marking individual juvenile birds, if tag loss can be reduced. Costs may be prohibitive in studies involving large numbers of birds.

  2. Development of the metanephros in the chick: maturation of glomerular size and nephron length.

    PubMed

    Gambaryan, S P

    1992-01-01

    In the avian kidney three nephron types may be identified: mammalian-type nephrons with long (MTN-I) and short (MTN-II) loops of Henlé, and reptilian-type nephrons (RTN). By the method of microdissection the maturation of the nephrons of domestic fowl kidney has been studied. From the 14th day of incubation it is possible to isolate the MTN-I which appear first; all three nephron types may be isolated after 18 days of incubation. The thin limb of Henlé's loop in MTN-I appears after hatching, and the length of this segment in 1-day-old chicks is 0.1-0.13 mm. In 60-day-old chicks its length has approximately doubled. The transition of the thin segment to the thick segment is situated in the descending part of Henlé's loop. In the course of development, the relative length of all nephron segments in MTN-I increases uniformly, while in MTN-II and in RTN the relative length of the proximal and distal convoluted tubules increases. At all stages of development, MTN-I are the longest among the three groups of nephrons and have the largest glomeruli. The comparison between developing avian and mammalian kidneys shows great similarities in the process of maturation in analogous nephron types in these two classes of vertebrates.

  3. Feasibility Study of Ex Ovo Chick Chorioallantoic Artery Model for Investigating Pulsatile Variation of Arterial Geometry.

    PubMed

    Nam, Kweon-Ho; Kim, Juho; Ra, Gicheol; Lee, Chong Hyun; Paeng, Dong-Guk

    2015-01-01

    Despite considerable research efforts on the relationship between arterial geometry and cardiovascular pathology, information is lacking on the pulsatile geometrical variation caused by arterial distensibility and cardiomotility because of the lack of suitable in vivo experimental models and the methodological difficulties in examining the arterial dynamics. We aimed to investigate the feasibility of using a chick embryo system as an experimental model for basic research on the pulsatile variation of arterial geometry. Optical microscope video images of various arterial shapes in chick chorioallantoic circulation were recorded from different locations and different embryo samples. The high optical transparency of the chorioallantoic membrane (CAM) allowed clear observation of tiny vessels and their movements. Systolic and diastolic changes in arterial geometry were visualized by detecting the wall boundaries from binary images. Several to hundreds of microns of wall displacement variations were recognized during a pulsatile cycle. The spatial maps of the wall motion harmonics and magnitude ratio of harmonic components were obtained by analyzing the temporal brightness variation at each pixel in sequential grayscale images using spectral analysis techniques. The local variations in the spectral characteristics of the arterial wall motion were reflected well in the analysis results. In addition, mapping the phase angle of the fundamental frequency identified the regional variations in the wall motion directivity and phase shift. Regional variations in wall motion phase angle and fundamental-to-second harmonic ratio were remarkable near the bifurcation area. In summary, wall motion in various arterial geometry including straight, curved and bifurcated shapes was well observed in the CAM artery model, and their local and cyclic variations could be characterized by Fourier and wavelet transforms of the acquired video images. The CAM artery model with the spectral

  4. Measurement of the photoreceptor pointing in the living chick eye.

    PubMed

    Walker, Maria K; Blanco, Leonardo; Kivlin, Rebecca; Choi, Stacey S; Doble, Nathan

    2015-04-01

    The chick eye is used in the study of ocular growth and emmetropization; however optical aberrations in the lens and cornea limit the ability to visualize fine retinal structure in living eyes. These aberrations can be corrected using adaptive optics (AO) allowing for cellular level imaging in vivo. Here, this capability is extended to measure the angular tuning properties of individual photoreceptors. The left eyes from two White Leghorn chicks (Gallus gallus domesticus) labeled chick A and chick B, were imaged using an AO flood illuminated fundus camera. By translating the entrance pupil position, the same retinal location was illuminated with light of varying angles allowing for the measurement of individual photoreceptor pointing. At 30° nasal from the pecten tip, the pointing direction for both chicks was towards the pupil center with a narrow distribution. These particular chicks were found to have a temporal (T) and inferior (I) bias in the alignment with peak positions of (0.81 T, 0.23 I) and (0.57 T, 0.18 I) mm from the pupil center for chicks A and B respectively. The rho, ρ, values for the major, ρL, and minor, ρs, axes were 0.14 and 0.17mm(-2) for chick A and 0.09 and 0.20mm(-2) for chick B. The small disarray in the alignment of the chick photoreceptors implies that the photoreceptors are aligned to optimize the light entering the eye through the central portion of the pupil aperture. The ability to measure pointing properties of individual photoreceptors will have application in the study of eye growth and various retinal disorders.

  5. Halogenated flame retardants during egg formation and chicken embryo development: maternal transfer, possible biotransformation, and tissue distribution.

    PubMed

    Zheng, Xiao-Bo; Luo, Xiao-Jun; Zeng, Yan-Hong; Wu, Jiang-Ping; Chen, She-Jun; Mai, Bi-Xian

    2014-08-01

    Hen muscle, eggs, and newborn chick tissues (muscle and liver) were collected from an electronic waste recycling site in southern China. The authors examined the maternal transfer, potential metabolism, and tissue distribution of several halogenated flame retardants (HFRs) during egg formation and chicken embryo development. The pollutant composition changes significantly from hen muscle to eggs and from eggs to tissues of newborn chicks. Higher-halogenated chemicals, such as octa- to deca-polybrominated diphenyl ether (PBDE) congeners, deca-polybrominated biphenyl (PBB209), and dechlorane plus (DP), are less readily transferred to eggs compared with lower-halogenated chemicals. During embryo development, PBDEs are the most likely to be metabolized, whereas decabromodiphenyl ethane (DBDPE) is the least. The authors also observed selective maternal transfer of anti-DP and stereoselective metabolism of syn-DP during chicken embryo development. During tissue development, liver has greater affinity than the muscle for chemcials with a high log octanol-water partition coefficient, with the exception of DBDPE. The differences in metabolism potential of different chemicals in chicken embryos cause pollutant composition alterations. Halogenated flame retardant from maternal transfer and tissue distribution also exhibited chemical specificity, especially for DBDPE. Levels of DBDPE were elevated along with the full process from hen muscle to eggs and from eggs to chick tissues. More attention should be paid to the selective accumulation and biotransformation of HFRs in the early development stage of birds. PMID:24888473

  6. Halogenated flame retardants during egg formation and chicken embryo development: maternal transfer, possible biotransformation, and tissue distribution.

    PubMed

    Zheng, Xiao-Bo; Luo, Xiao-Jun; Zeng, Yan-Hong; Wu, Jiang-Ping; Chen, She-Jun; Mai, Bi-Xian

    2014-08-01

    Hen muscle, eggs, and newborn chick tissues (muscle and liver) were collected from an electronic waste recycling site in southern China. The authors examined the maternal transfer, potential metabolism, and tissue distribution of several halogenated flame retardants (HFRs) during egg formation and chicken embryo development. The pollutant composition changes significantly from hen muscle to eggs and from eggs to tissues of newborn chicks. Higher-halogenated chemicals, such as octa- to deca-polybrominated diphenyl ether (PBDE) congeners, deca-polybrominated biphenyl (PBB209), and dechlorane plus (DP), are less readily transferred to eggs compared with lower-halogenated chemicals. During embryo development, PBDEs are the most likely to be metabolized, whereas decabromodiphenyl ethane (DBDPE) is the least. The authors also observed selective maternal transfer of anti-DP and stereoselective metabolism of syn-DP during chicken embryo development. During tissue development, liver has greater affinity than the muscle for chemcials with a high log octanol-water partition coefficient, with the exception of DBDPE. The differences in metabolism potential of different chemicals in chicken embryos cause pollutant composition alterations. Halogenated flame retardant from maternal transfer and tissue distribution also exhibited chemical specificity, especially for DBDPE. Levels of DBDPE were elevated along with the full process from hen muscle to eggs and from eggs to chick tissues. More attention should be paid to the selective accumulation and biotransformation of HFRs in the early development stage of birds.

  7. Wild-laid versus captive-laid eggs in the black-bellied sandgrouse: is there any effect on chick productivity?

    PubMed

    Aourir, M; Znari, M; Radi, M; Melin, J-M

    2013-01-01

    Because survival in captivity is a significant determinant of birds available for release and reinforcement of wild populations, we aimed to identify sources of variation in mortality to assess potential impacts of management on chick productivity. We analyzed characteristics of Black-bellied Sandgrouse eggs collected from the wild and produced by captive pairs. Wild laid-eggs and pulled captive-laid eggs were incubated artificially and all chicks were hand-reared until seven weeks of age. Wild-laid eggs were significantly bigger, heavier, and denser than captive-laid eggs which showed a higher variability in size. Fertility, embryo mortality, and fertile egg hatchability were similar for wild-laid and captive-laid eggs (67.92% vs. 68%; 15.62% vs. 15.7%, and 80.55% vs. 84.44%, respectively). There were significant positive relationships between egg weigh/volume and chick hatch weight. Mortality of chicks hatched from wild-laid eggs was much lower than that of chicks from captive-laid eggs (19.44% vs. 60.5%) during the first week after hatching, but decreased and being nil from the third week. Heavier hatchlings from captive-laid eggs exhibited higher survival rates which is not the case of hatchlings from wild-laid eggs. These latter hatchlings had higher survival rates increasing with the age of eggs in relation with the period of natural incubation. The recommended age at which wild-laid eggs could be collected is at least 13 days for full chick survivability. We concluded that in our experimental captive breeding program of the Black-bellied Sandgrouse, productivity of viable hatchlings was much better from wild-laid eggs and as later as these were collected.

  8. Thalidomide induces limb anomalies by PTEN stabilization, Akt suppression, and stimulation of caspase-dependent cell death.

    PubMed

    Knobloch, Jürgen; Schmitz, Ingo; Götz, Katrin; Schulze-Osthoff, Klaus; Rüther, Ulrich

    2008-01-01

    Thalidomide, a drug used for the treatment of multiple myeloma and inflammatory diseases, is also a teratogen that causes birth defects, such as limb truncations and microphthalmia, in humans. Thalidomide-induced limb truncations result from increased cell death during embryonic limb development and consequential disturbance of limb outgrowth. Here we demonstrate in primary human embryonic cells and in the chicken embryo that thalidomide-induced signaling through bone morphogenetic proteins (Bmps) protects active PTEN from proteasomal degradation, resulting in suppression of Akt signaling. As a consequence, caspase-dependent cell death is stimulated by the intrinsic and Fas death receptor apoptotic pathway. Most importantly, thalidomide-induced limb deformities and microphthalmia in chicken embryos could be rescued by a pharmacological PTEN inhibitor as well as by insulin, a stimulant of Akt signaling. We therefore conclude that perturbation of PTEN/Akt signaling and stimulation of caspase activity is central to the teratogenic effects of thalidomide.

  9. [Lentivirus Delivery of the Short Hairpin RNA Targeting NDV P Gene Inhibits Production of the Newcastle Disease Virus in Chicken Embryo Fibroblasts and Chicken Embryos].

    PubMed

    Yang, Shaohua; Xu, Chuantian; Zhang, Lin; Huang, Yanyan; Huang, Qinghua; Hu, Beixia; Zhang, Xiumei

    2016-01-01

    Small interfering ribonucleic acid (siRNA)-induced RNA degradation can inhibit viral infection, and has been investigated extensively for its efficacy as antiviral therapy. The potential therapeutic role of lentiviral-mediated short hairpin ribonucleic acid (shRNA) to Newcastle disease virus (NDV) replication in vivo has been explored less often. We constructed two recombinant lentiviral vectors containing shRNA against the phosphoprotein (P) of the NDV, RNAi-341 and RNAi-671. Recombinant shRNA lentivirus vectors were co-transfected into 293T cells, along with helper plasmids, to package the recombinant shRNA lentivirus. Lentivirus-based shRNAs were titrated and transduced into NDV-susceptible chicken embryo fibroblasts (CEFs) and chick embryos. Antiviral activity against the NDV strain was evaluated by virus titration and real-time reverse transcription-polymerase chain reaction. RNAi-341 and RNAi-671 strongly suppressed transient expression of a FLAG-tagged P fusion protein in 293T cells. RNAi-341 and RNAi-671 NDV reduced virus titers by 66.6-fold and 30.6-fold, respectively, in CEFs 16 h after infection. RNAi-341 and RNAi-671 reduced virus titers in specific pathogen-free chick embryos by 99% and 98%, respectively, 48 h after infection. Both shRNAs inhibited accumulation of not only P-gene mRNA, but also nucleocapsid, M-, F-, HN-, and L-gene mRNA. RNAi-341 silenced P-gene mRNA more potently than RNAi-671. These results suggest that shRNAs silencing the P gene had substantial antiviral properties and inhibited NDV replication in CEFs and chick embryos. PMID:27295882

  10. [Lentivirus Delivery of the Short Hairpin RNA Targeting NDV P Gene Inhibits Production of the Newcastle Disease Virus in Chicken Embryo Fibroblasts and Chicken Embryos].

    PubMed

    Yang, Shaohua; Xu, Chuantian; Zhang, Lin; Huang, Yanyan; Huang, Qinghua; Hu, Beixia; Zhang, Xiumei

    2016-01-01

    Small interfering ribonucleic acid (siRNA)-induced RNA degradation can inhibit viral infection, and has been investigated extensively for its efficacy as antiviral therapy. The potential therapeutic role of lentiviral-mediated short hairpin ribonucleic acid (shRNA) to Newcastle disease virus (NDV) replication in vivo has been explored less often. We constructed two recombinant lentiviral vectors containing shRNA against the phosphoprotein (P) of the NDV, RNAi-341 and RNAi-671. Recombinant shRNA lentivirus vectors were co-transfected into 293T cells, along with helper plasmids, to package the recombinant shRNA lentivirus. Lentivirus-based shRNAs were titrated and transduced into NDV-susceptible chicken embryo fibroblasts (CEFs) and chick embryos. Antiviral activity against the NDV strain was evaluated by virus titration and real-time reverse transcription-polymerase chain reaction. RNAi-341 and RNAi-671 strongly suppressed transient expression of a FLAG-tagged P fusion protein in 293T cells. RNAi-341 and RNAi-671 NDV reduced virus titers by 66.6-fold and 30.6-fold, respectively, in CEFs 16 h after infection. RNAi-341 and RNAi-671 reduced virus titers in specific pathogen-free chick embryos by 99% and 98%, respectively, 48 h after infection. Both shRNAs inhibited accumulation of not only P-gene mRNA, but also nucleocapsid, M-, F-, HN-, and L-gene mRNA. RNAi-341 silenced P-gene mRNA more potently than RNAi-671. These results suggest that shRNAs silencing the P gene had substantial antiviral properties and inhibited NDV replication in CEFs and chick embryos.

  11. Homology, limbs, and genitalia.

    PubMed

    Minelli, Alessandro

    2002-01-01

    Similarities in genetic control between the main body axis and its appendages have been generally explained in terms of genetic co-option. In particular, arthropod and vertebrate appendages have been explained to invoke a common ancestor already provided with patterned body outgrowths or independent recruitment in limb patterning of genes or genetic cassettes originally used for purposes other than axis patterning. An alternative explanation is that body appendages, including genitalia, are evolutionarily divergent duplicates (paramorphs) of the main body axis. However, are all metazoan limbs and genitalia homologous? The concept of body appendages as paramorphs of the main body axis eliminates the requirement for the last common ancestor of limb-bearing animals to have been provided with limbs. Moreover, the possibility for an animal to express complex organs ectopically demonstrates that positional and special homology may be ontogenetically and evolutionarily uncoupled. To assess the homology of animal genitalia, we need to take into account three different sets of mechanisms, all contributing to their positional and/or special homology and respectively involved (1) in the patterning of themain body axis, (2) in axis duplication, followed by limb patterning mechanisms diverging away from those still patterning the main body axis (axis paramorphism), and (3) in controlling the specification of sexual/genital features, which often, but not necessarily, come into play by modifying already developed and patterned body appendages. This analysis demonstrates that a combinatorial approach to homology helps disentangling phylogenetic and ontogenetic layers of homology.

  12. Object Individuation in 3-Day-Old Chicks: Use of Property and Spatiotemporal Information

    ERIC Educational Resources Information Center

    Fontanari, Laura; Rugani, Rosa; Regolin, Lucia; Vallortigara, Giorgio

    2011-01-01

    Object individuation was investigated in newborn domestic chicks. Chicks' spontaneous tendency to approach the larger group of familiar objects was exploited in a series of five experiments. In the first experiment newborn chicks were reared for 3 days with objects differing in either colour, shape or size. At test, each chick was presented with…

  13. Effects of LED lighting during incubation on layer and broiler hatchability, chick quality, stress susceptibility and post-hatch growth.

    PubMed

    Huth, Jesse C; Archer, Gregory S

    2015-12-01

    Providing light during incubation has been shown to affect hatchability, but the use of LED lights has not been evaluated. This experiment evaluated the effects of LED lighting during embryogenesis on White Leghorn and commercial broiler eggs. To determine this, two experiments were conducted, the first using White Leghorn eggs (N=3456) and the second using commercial broiler eggs (N=3456) where eggs were incubated 12 h of light and 12 h of darkness (LED) or complete darkness (DARK); the light level was 250 lux. Hatchability, embryo mortality, and chick quality were measured in both studies, and a subset of one of the broiler egg trials were grown out to investigate fear and stress parameters. There was no effect (P>0.05) on hatchability of layer eggs; however, there was a difference (P=0.02) observed in chick quality, with the LED group having more chicks (75.34%) with no defects than the DARK group (56.53%). Broiler eggs exposed to LED light showed an increase in hatchability (90.12%, P=0.03) and an increase in no-defect chick percentage (86.12%, P=0.04) at hatch compared to the DARK chicks (85.76% and 69.43%, respectively). Differences were observed between treatments during the 14 d grow-out. The LED birds had lower (P<0.05) physical asymmetry (0.90±0.05 mm) and heterophil/lymphocyte ratios (0.279±0.021), indicating that they were less susceptible to stress than the DARK birds (1.16±0.07 mm and 0.347±0.021, respectively). There was no difference (P>0.05) observed between treatments in growth, FCR, or fear measures at 14 d. These results indicate that providing LED light during incubation can improve chick quality in both white layer and broiler eggs; however, it only appears to improve hatchability in broilers, which could be related to shell pigmentation. It was also demonstrated that providing LED light during incubation can reduce the stress susceptibility of broilers post-hatch. Utilizing light during incubation may be useful tool for the poultry

  14. Mass stranding of wedge-tailed shearwater chicks in Hawaii

    USGS Publications Warehouse

    Work, T.M.; Rameyer, R.A.

    1999-01-01

    Unusual numbers of wedge-tailed shearwater (Puffinus pacificus) chicks stranded on Oahu (Hawaii, USA) in 1994. Compared to healthy wedge-tailed shearwater (WTSW) chicks, stranded chicks were underweight, dehydrated, leukopenic, lymphopenic, eosinopenic, and heterophilic; some birds were toxemic and septic. Stranded chicks also were hypoglycemic and had elevated aspartate amino transferase levels. Most chicks apparently died from emaciation, dehydration, or bacteremia. Because many birds with bacteremia also had severe necrosis of the gastrointestinal (GI) mucosa associated with bacteria, we suspect the GI tract to be the source of disseminated bacterial infection. The identity of the bacteria was not confirmed. The daily number of chicks stranded was significantly related to average wind speeds, and the mortality coincided with the fledging period for WTSW. Strong southeasterly winds were a distinguishing meteorologic factor in 1994 and contributed to the distribution of stranded chicks on Oahu. More objective data on WTSW demographics would enhance future efforts to determine predisposing causes of WTSW wrecks and their effects on seabird colonies.

  15. [Characteristics of morphogenesis of the Japanese quail embryos during microgravity

    NASA Technical Reports Server (NTRS)

    Dadasheva, O. A.; Gur'eva, T. S.; Sychev, V. N.; Jehns, G.; Jahns, G. (Principal Investigator)

    1998-01-01

    Experiments performed in the period of 1995-1996 cooperatively with US investigators within the MIR/SHUTTLE and MIR/NASA space science projects continued exploration of avian embryogenesis in microgravity. Evaluation of Japanese quail embryos incubated in spaceflight microgravity showed that for the most part they were normally developed and compliant with duration of incubation. One of the major morphometric characteristics of embryo are its mass and size. Comparative analysis of body mass values in the space and laboratory and synchronous control groups pointed to a slight retardation. Body length of space embryos mimicked their mass curve. Data on the dynamics of mass and length of Japanese quail embryos support the well-known theory according to which growth and formation are distinguished by equifinality. No differences were revealed by the investigations of individual parts of embryonic bodies in the space and control groups. However, this finding was true only with regard to the embryos that had no developmental abnormalities. A part of embryos had defective eyes (microphtalmia), limbs (twisted fingers), and beaks.

  16. Light experience and the development of behavioural lateralisation in chicks. II. Choice of familiar versus unfamiliar model social partner.

    PubMed

    Andrew, Richard J; Johnston, Amy N B; Robins, Andrew; Rogers, Lesley J

    2004-11-01

    In late-stage embryos of domestic fowl, exposure of the right eye to light entering through the shell induces asymmetry of the thalamofugal visual pathway, together with differences in performance according to whether the right or left eye (RE, LE) is in use (Behav. Brain Res. 38 (1990) 211). Nevertheless, at least some of the main specialisations of the right and left eye systems (RES, LES) are not dependent on such exposure. Higher ability of LES to assess and respond to novelty is present in dark-incubated (Da) chicks. This is probably also true of RES ability to control response, and specifically to inhibit shift to an alternative response (i.e. to a novel stimulus). We imprinted chicks on red table-tennis balls with a horizontal, white strip on their equator. At test, they chose between this and a ball with a vertical, white strip. Da chicks showed clear choice with the LE, but not with the RE. Unexpectedly, light-incubated (Li) chicks failed to show LE/RE differences in choice. Exploratory pecks at a novel feature were greatly reduced in Li. Two effects of light exposure on RES are likely. The first is greater use of RES in the home-cage, affecting what is learned about the companion ball. This may make RES more competent in assessing ball properties, and so explain the enhanced choice by RE, that abolished the RE/LE difference in Li. Secondly, the ability of RES to inhibit shift to an alternative response is enhanced. Light exposure and being female similarly opposed shift to the novel feature, but probably via different mechanisms. The effects of exposure are discussed as an example of the generation of a range of behavioural phenotypes, which are sustained within a single population by varying or frequency-dependent selection. PMID:15325780

  17. Light experience and the development of behavioural lateralisation in chicks. II. Choice of familiar versus unfamiliar model social partner.

    PubMed

    Andrew, Richard J; Johnston, Amy N B; Robins, Andrew; Rogers, Lesley J

    2004-11-01

    In late-stage embryos of domestic fowl, exposure of the right eye to light entering through the shell induces asymmetry of the thalamofugal visual pathway, together with differences in performance according to whether the right or left eye (RE, LE) is in use (Behav. Brain Res. 38 (1990) 211). Nevertheless, at least some of the main specialisations of the right and left eye systems (RES, LES) are not dependent on such exposure. Higher ability of LES to assess and respond to novelty is present in dark-incubated (Da) chicks. This is probably also true of RES ability to control response, and specifically to inhibit shift to an alternative response (i.e. to a novel stimulus). We imprinted chicks on red table-tennis balls with a horizontal, white strip on their equator. At test, they chose between this and a ball with a vertical, white strip. Da chicks showed clear choice with the LE, but not with the RE. Unexpectedly, light-incubated (Li) chicks failed to show LE/RE differences in choice. Exploratory pecks at a novel feature were greatly reduced in Li. Two effects of light exposure on RES are likely. The first is greater use of RES in the home-cage, affecting what is learned about the companion ball. This may make RES more competent in assessing ball properties, and so explain the enhanced choice by RE, that abolished the RE/LE difference in Li. Secondly, the ability of RES to inhibit shift to an alternative response is enhanced. Light exposure and being female similarly opposed shift to the novel feature, but probably via different mechanisms. The effects of exposure are discussed as an example of the generation of a range of behavioural phenotypes, which are sustained within a single population by varying or frequency-dependent selection.

  18. Relative utilization of serine and glycine by chicks.

    PubMed

    Featherston, W R

    1975-01-01

    Studies were conducted on the relative utilizaiton of glycine and serine by chicks fed basal crystalline amino acid diets devoid of these amino acids. The crystalline amino acid mixture was fed at one and three times the requirement levels, thereby stimulating uric acid synthesis at differing rates. In addition, 5 per cent L-glutamine replaced L-glutamic acid on an isonitrogenous basis in three diets containing normal levels of amino acids in the second study. Chicks fed diets devoid of glycine and serine grew less rapidly and less efficiently than chicks fed diets containing either serine or glycine plus serine. These decreases were roughly the same whether the diet contained normal or high levels of amino acids. Serine was as efficient as glycine in supporting chick growth and feed efficiency regardless of whether diets containing normal or high levels of amino acids were fed. Chicks fed diets containing high levels of amino acids grew approximately 81 per cent as rapidly, but 24 per cent more efficiently, than chicks fed normal levels of amino acids, and excreted approximately twice the amount of uric acid per gram of nitrogen consumed. In spite of increased uric acid excretion by chicks fed the high amino acid diets, the dietary void in glycine and serine was no more detrimental to chick growth or feed efficiency than that noted when normal levels of amino acids were fed. Feeding 5 per cent L-glutamine rather than L-glutamic acid in the diet containing normal levels of amino acids had little effect on weight gain, feed efficiency or uric acid excretion. The absence of cystine from the amino acid mixture used in the third study did not have a marked influence on the relative utilization of glycine and serine by the chick. PMID:1169769

  19. Genetic diagnosis of human embryos.

    PubMed

    Bonnicksen, Andrea

    1992-01-01

    For all the worried talk about genetic engineering over the last two decades, it is surprising how quietly plans for the genetic diagnosis of human embryos have developed. The issues raised warrant careful examination: what needs are met through embryo diagnosis? Who bears responsibility for monitoring this technique? Under what overarching ethic should embryo diagnosis and, eventually, embryo therapy, be applied? What are the broader social implications raised by the genetic diagnosis of human embryos?

  20. Limb salvage surgery.

    PubMed

    Kadam, Dinesh

    2013-05-01

    The threat of lower limb loss is seen commonly in severe crush injury, cancer ablation, diabetes, peripheral vascular disease and neuropathy. The primary goal of limb salvage is to restore and maintain stability and ambulation. Reconstructive strategies differ in each condition such as: Meticulous debridement and early coverage in trauma, replacing lost functional units in cancer ablation, improving vascularity in ischaemic leg and providing stable walking surface for trophic ulcer. The decision to salvage the critically injured limb is multifactorial and should be individualised along with laid down definitive indications. Early cover remains the standard of care, delayed wound coverage not necessarily affect the final outcome. Limb salvage is more cost-effective than amputations in a long run. Limb salvage is the choice of procedure over amputation in 95% of limb sarcoma without affecting the survival. Compound flaps with different tissue components, skeletal reconstruction; tendon transfer/reconstruction helps to restore function. Adjuvant radiation alters tissue characters and calls for modification in reconstructive plan. Neuropathic ulcers are wide and deep often complicated by osteomyelitis. Free flap reconstruction aids in faster healing and provides superior surface for offloading. Diabetic wounds are primarily due to neuropathy and leads to six-fold increase in ulcerations. Control of infections, aggressive debridement and vascular cover are the mainstay of management. Endovascular procedures are gaining importance and have reduced extent of surgery and increased amputation free survival period. Though the standard approach remains utilising best option in the reconstruction ladder, the recent trend shows running down the ladder of reconstruction with newer reliable local flaps and negative wound pressure therapy.

  1. Limb salvage surgery

    PubMed Central

    Kadam, Dinesh

    2013-01-01

    The threat of lower limb loss is seen commonly in severe crush injury, cancer ablation, diabetes, peripheral vascular disease and neuropathy. The primary goal of limb salvage is to restore and maintain stability and ambulation. Reconstructive strategies differ in each condition such as: Meticulous debridement and early coverage in trauma, replacing lost functional units in cancer ablation, improving vascularity in ischaemic leg and providing stable walking surface for trophic ulcer. The decision to salvage the critically injured limb is multifactorial and should be individualised along with laid down definitive indications. Early cover remains the standard of care, delayed wound coverage not necessarily affect the final outcome. Limb salvage is more cost-effective than amputations in a long run. Limb salvage is the choice of procedure over amputation in 95% of limb sarcoma without affecting the survival. Compound flaps with different tissue components, skeletal reconstruction; tendon transfer/reconstruction helps to restore function. Adjuvant radiation alters tissue characters and calls for modification in reconstructive plan. Neuropathic ulcers are wide and deep often complicated by osteomyelitis. Free flap reconstruction aids in faster healing and provides superior surface for offloading. Diabetic wounds are primarily due to neuropathy and leads to six-fold increase in ulcerations. Control of infections, aggressive debridement and vascular cover are the mainstay of management. Endovascular procedures are gaining importance and have reduced extent of surgery and increased amputation free survival period. Though the standard approach remains utilising best option in the reconstruction ladder, the recent trend shows running down the ladder of reconstruction with newer reliable local flaps and negative wound pressure therapy. PMID:24501463

  2. Social hierarchies in very young chicks.

    PubMed

    Rogers, L J; Astiningsih, K

    1991-03-01

    1. Three behavioural tests involving social competition were used to determine rank orders in groups of 8 male chicks aged between 4 and 18 days posthatching. 2. The group structure was found to consist of one or two dominant animals which consistently held a position at the top of the rank order, with a more flexible order beneath this. 3. Compared to the top-ranking birds, the middle- and lower-ranking birds showed more variability in their ranking positions across the behavioural tests and the testing periods. 4. Treatment of the lowest ranking individual in each group with testosterone led to this individual's rise in the rank order, most often to the top rank.

  3. On the development of Cetacean extremities: I. Hind limb rudimentation in the Spotted dolphin (Stenella attenuata).

    PubMed

    Sedmera, D; Misek, I; Klima, M

    1997-02-01

    The Cetacea are group of animals which have completely lost their hind limbs during the course of evolution as a result of their entirely aquatic mode of life. It is known, however, that during their embryonal period, the hind limb buds are temporarily present. The control mechanisms of this regression are not yet understood, and vestigial limbs can sometimes be found in adults. The aim of the present study is to describe the course of hind limb rudimentation during prenatal development of Stenella attenuata (Spotted dolphin) at tissue and cell levels and compare the results with other natural or experimentally induced amelias. Hind limb buds of dolphin embryos, CRL 10-30 mm, were examined histologically. Before total disappearance, they show histodifferentiation comparable with other mammals. Initially, they form the apical ectodermal ridge, which soon regresses. The mesenchyme undergoes the process of condensation to form anlagens of prospective skeletal elements. These condensations are surrounded by vascular plexuses. During the course of rudimentation, some mesenchymal cells die, while the others are incorporated into the body wall. Nerve ingrowth into rudimentary limb buds was also detected. The temporary presence of hind limb rudiments in cetacean embryos can be regarded as a good example of recapitulation of phylogenesis in ontogenesis. PMID:9143876

  4. Distinct spatiotemporal roles of hedgehog signalling during chick and mouse cranial base and axial skeleton development

    PubMed Central

    Balczerski, B.; Zakaria, S.; Tucker, A. S.; Borycki, A.G.; Koyama, E.; Pacifici, M.; Francis-West, P.

    2012-01-01

    The cranial base exerts a supportive role for the brain and includes the occipital, sphenoid and ethmoid bones that arise from cartilaginous precursors in the early embryo. As the occipital bone and the posterior part of the sphenoid are mesoderm derivatives that arise in close proximity to the notochord and floor plate, it has been assumed that their development, like the axial skeleton, is dependent on Sonic hedgehog (Shh) and modulation of bone morphogenetic protein (Bmp) signalling. Here we examined the development of the cranial base in chick and mouse embryos to compare the molecular signals that are required for chondrogenic induction in the trunk and head. We found that Shh signalling is required but the molecular network controlling cranial base development is distinct from that in the trunk. In the absence of Shh, the presumptive cranial base did not undergo chondrogenic commitment as determined by the loss of Sox9 expression and there was a decrease in cell survival. In contrast, induction of the otic capsule occurred normally demonstrating that induction of the cranial base is uncoupled from formation of the sensory capsules. Lastly, we found that the early cranial mesoderm is refractory to Shh signalling, likely accounting for why development of the cranial base occurs after the axial skeleton. Our data reveal that cranial and axial skeletal induction is controlled by conserved, yet spatiotemporally distinct mechanisms that co-ordinate development of the cranial base with that of the cranial musculature and the pharyngeal arches. PMID:23009899

  5. A cannabinoid analogue of Delta9-tetrahydrocannabinol disrupts neural development in chick.

    PubMed

    Psychoyos, Delphine; Hungund, Basalingappa; Cooper, Thomas; Finnell, Richard H

    2008-10-01

    Marijuana is the most commonly abused illicit drug by pregnant women. Its major psychoactive constituent, Delta(9)-THC (Delta(9)-tetrahydrocannabinol), crosses the placenta and accumulates in the foetus, potentially harming its development. In humans, marijuana use in early pregnancy is associated with miscarriage, a fetal alcohol-like syndrome, as well as learning disabilities, memory impairment, and ADHD in the offspring. Classical studies in the 1970 s have reached disparate conclusions as to the teratogenic effects of cannabinoids in animal models. Further, there is very little known about the immediate effects of Delta(9)-THC on early embryogenesis. We have used the chick embryo as a model in order to characterize the effects of a water-soluble Delta(9)-THC analogue, O-2545, on early development. Embryos were exposed to the drug (0.035 to 0.35 mg/ml) at gastrulation and assessed for morphological defects at stages equivalent to 9-14 somites. We report that O-2545 impairs the formation of brain, heart, somite, and spinal cord primordia. Shorter incubation times following exposure to the drug show that O-2545 interferes with the initial steps of head process and neural plate formation. Our results indicate that the administration of the cannabinoid O-2545 during early embryogenesis results in embryotoxic effects and serves to illuminate the risks of marijuana exposure during the second week of pregnancy, a time point at which most women are unaware of their pregnancies. PMID:19040278

  6. A cannabinoid analogue of Delta9-tetrahydrocannabinol disrupts neural development in chick.

    PubMed

    Psychoyos, Delphine; Hungund, Basalingappa; Cooper, Thomas; Finnell, Richard H

    2008-10-01

    Marijuana is the most commonly abused illicit drug by pregnant women. Its major psychoactive constituent, Delta(9)-THC (Delta(9)-tetrahydrocannabinol), crosses the placenta and accumulates in the foetus, potentially harming its development. In humans, marijuana use in early pregnancy is associated with miscarriage, a fetal alcohol-like syndrome, as well as learning disabilities, memory impairment, and ADHD in the offspring. Classical studies in the 1970 s have reached disparate conclusions as to the teratogenic effects of cannabinoids in animal models. Further, there is very little known about the immediate effects of Delta(9)-THC on early embryogenesis. We have used the chick embryo as a model in order to characterize the effects of a water-soluble Delta(9)-THC analogue, O-2545, on early development. Embryos were exposed to the drug (0.035 to 0.35 mg/ml) at gastrulation and assessed for morphological defects at stages equivalent to 9-14 somites. We report that O-2545 impairs the formation of brain, heart, somite, and spinal cord primordia. Shorter incubation times following exposure to the drug show that O-2545 interferes with the initial steps of head process and neural plate formation. Our results indicate that the administration of the cannabinoid O-2545 during early embryogenesis results in embryotoxic effects and serves to illuminate the risks of marijuana exposure during the second week of pregnancy, a time point at which most women are unaware of their pregnancies.

  7. Artificial limb connection

    NASA Technical Reports Server (NTRS)

    Owens, L. J.

    1974-01-01

    Connection simplifies and eases donning and removing artificial limb; eliminates harnesses and clamps; and reduces skin pressures by allowing bone to carry all tensile and part of compressive loads between prosthesis and stump. Because connection is modular, it is easily modified to suit individual needs.

  8. Accessories to Limb Regeneration.

    PubMed

    Han, Yanchao; Poss, Kenneth D

    2016-05-23

    In a recent issue of Nature, Nacu et al. (2016) identified FGF and HH ligands as interacting molecular influences that are necessary and sufficient to induce the formation of supernumerary limbs from blastemal tissue in axolotl salamanders. PMID:27219058

  9. Effect of Green Light on Nitric Oxide Metabolism in Chick Embryos. A Possible Physiological Role.

    PubMed

    Titov, V Yu; Kosenko, O V; Starkova, E S; Kondratov, G V; Borkhunova, E N; Ivanova, A V

    2015-10-01

    The exposure to green light, which serves as a well-known activating factor for myogenesis during incubation of chicken eggs, contributes to intensification of embryonic metabolism of NO. A metabolic product, nitrate, is mainly accumulated in the muscles. These data suggest that light induces a NO-dependent activation of the factor, which intensifies muscle tissue development.

  10. The role of oxygen in prenatal growth: studies in the chick embryo

    PubMed Central

    Giussani, Dino A; Salinas, Carlos E; Villena, Mercedes; Blanco, Carlos E

    2007-01-01

    The compelling evidence linking small size at birth with later cardiovascular disease has renewed and amplified scientific and clinical interests into the determinants of fetal growth. It is accepted that genes and nutrition control fetal growth; however, prior to this study, it had been impossible to isolate the effect of increases and decreases in fetal oxygenation on the regulation of prenatal growth. We investigated the role of oxygen in the control of fetal growth in the chicken because in contrast to mammals, the effects on the fetus of changes in oxygenation could be isolated, by assessing them directly without alteration to the maternal or placental physiology or maternal nutrition during development. The data show that incubation at high altitude of fertilized eggs laid by sea level hens markedly restricted fetal growth. Incubation at high altitude of fertilized eggs laid by high altitude hens also restricted fetal growth, but to a lesser extent compared to eggs laid by sea level hens. By contrast, incubation at sea level of fertilized eggs laid by high altitude hens not only restored, but enhanced, fetal growth relative to sea level controls. Incubation at high altitude of sea level eggs with oxygen supplementation completely prevented the high altitude-induced fetal growth restriction. Thus, fetal oxygenation, independent of maternal nutrition during development, has a predominant role in the control of fetal growth. Further, prolonged high altitude residence confers protection against the deleterious effects of hypoxia on fetal growth. PMID:17962335

  11. Vitamin E-Induced Changes in Glutamate and GABA Metabolizing Enzymes of Chick Embryo Cerebrum

    PubMed Central

    Dessai, Shanti N.; Pinto, Annaliza

    2013-01-01

    Vitamin E exists in eight different forms, four tocopherols and four tocotrienols. It forms an important component of our antioxidant system. The structure of Vitamin E makes it unique and indispensable in protecting cell membranes. α-tocopherol, one of the forms of Vitamin E, is also known to regulate signal transduction pathways by mechanisms that are independent of its antioxidant properties. Vitamin E compounds reduce the production of inflammatory compounds such as prostaglandins. Swollen, dystrophic axons are considered as the hallmark of Vitamin E deficiency in the brains of rats, monkeys, and humans. The present work aimed to study the Vitamin E- (α-tochopherol acetate-) induced alterations of enzymes involved in metabolism of Glutamate and GABA during developmental neurogenesis of cerebrum. Therefore, cytosolic and crude mitochondrial enzyme activities of glutamine synthetase, aspartate transaminase, alanine transaminase, GABA transaminase, succinic Semialdehyde dehydrogenase, glutamic dehydrogenase, and α-Ketoglutarate dehydrogenase were analysed. Vitamin E induced significant changes in these enzymes thus altering the normal levels of glutamate and GABA during developmental neurogenesis. Such changes are surely to disturb the expression and/or intensity of neurotransmitter signaling during critical periods of brain development. PMID:23984094

  12. [Rudimentary stages of the extremities of Scelotes gronovii (Daudin) embryos, a South African Scincidea reptile].

    PubMed

    Raynaud, A; Van den Elzen, P

    1976-01-01

    The development of the limbs has been studied in 15 embryos of Scelotes gronovii, found in 8 ovoviviparous females collected at Saldanha Bay, in South Africa, Cape Province. This study leads to the following constatations: In all the young embryos of this species, their appears anlagen of anterior and of posterior limb-buds. The primordia of forelimb-buds retrogress early and disappear, whereas the primordia of hind limb-buds transform into rudimentary limbs which persist in adult. Histological study of the anlagen of fore limb buds establish that 7 somites (S6 to S12, S1 being the first post-otic somite) send ventral processes in the mesoblast of the anlage. These processes follow a sinuous pathway in the limb-bud, and are bent towards the basal cell layer of the somatopleural mesoderm. On the apical part of the limb-bud lie a wholly rudimentary epiblastic ridge, which disappears early. On the apical part of the hind limb-bud an ectodermic ridge is present, well differentiated which transforms soon in an apical fold; and the anlage of the hind limb produced a short conical appendage with short femur, tibia and fibula and one terminal finger. A comparison was made of the main steps of the development of the limbs in three species of Scelotes with rudimentary limbs. Scelotes inornatus, Scelotes brevipes and Scelotes gronovii. In these three species the ectodermal apical ridge of the fore limb-buds is rudimentary or incompletely differentiated; it never transforms into an ectodermal fold and its retrogresses rapidly; and in these species an early arrest of development and an involution of the primordia of the limb-buds occurs. These fact corroborate the anterior observations made on embryos of Anguis fragilis and of Ophisaurus apodus and they strengthen the interpretation postulating that the spontaneous retrogression of the apical ridge is an essential factor in the morphogenetic events involved in the arrest of development of the limb bud in the snake-like Reptiles.

  13. Artificial Polychromatic Light Affects Growth and Physiology in Chicks

    PubMed Central

    Yang, Bo; Yu, Yonghua

    2014-01-01

    Despite the overwhelming use of artificial light on captive animals, its effect on those animals has rarely been studied experimentally. Housing animals in controlled light conditions is useful for assessing the effects of light. The chicken is one of the best-studied animals in artificial light experiments, and here, we evaluate the effect of polychromatic light with various green and blue components on the growth and physiology in chicks. The results indicate that green-blue dual light has two side-effects on chick body mass, depending on the various green to blue ratios. Green-blue dual light with depleted and medium blue component decreased body mass, whereas enriched blue component promoted body mass in chicks compared with monochromatic green- or blue spectra-treated chicks. Moreover, progressive changes in the green to blue ratios of green-blue dual light could give rise to consistent progressive changes in body mass, as suggested by polychromatic light with higher blue component resulting in higher body mass. Correlation analysis confirmed that food intake was positively correlated with final body mass in chicks (R2 = 0.7664, P = 0.0001), suggesting that increased food intake contributed to the increased body mass in chicks exposed to higher blue component. We also found that chicks exposed to higher blue component exhibited higher blood glucose levels. Furthermore, the glucose level was positively related to the final body mass (R2 = 0.6406, P = 0.0001) and food intake (R2 = 0.784, P = 0.0001). These results demonstrate that spectral composition plays a crucial role in affecting growth and physiology in chicks. Moreover, consistent changes in spectral components might cause the synchronous response of growth and physiology. PMID:25469877

  14. Distribution of viral antigens and development of lesions in chicken embryos inoculated with nipah virus.

    PubMed

    Tanimura, N; Imada, T; Kashiwazaki, Y; Sharifah, S H

    2006-01-01

    An isolate of Nipah virus was injected into fertile eggs via the allantoic cavity or yolk sac. Allantoic inoculation resulted in considerable pathological variation and only partial mortality. Dead embryos showed severe necrosis in the brain and congestion in the kidney and the subcutis of limbs. In contrast, yolk sac inoculation led to uniform infection and mortality, the dead embryos exhibiting the same lesions as those described above but without the subcutaneous congestion. Histological lesions in dead embryos inoculated by either route were similar and particularly severe in the central nervous system. Viral antigens were detected mainly in the vasculature and neurons. The results indicated that Nipah virus is highly pathogenic to chicken embryos, and that the route of inoculation is an important determinant of the course of disease. The findings also suggested that yolk sac inoculation can be used for viral titration, and that the chicken embryo represents a useful model for studying the vascular and neuronal tropisms of Nipah virus.

  15. Peripheral Insulin Doesn't Alter Appetite of Broiler Chicks.

    PubMed

    Liu, Lei; Xu, Shaohua; Wang, Xiaojuan; Jiao, Hongchao; Lin, Hai

    2016-09-01

    An experiment was conducted to investigate the effect of peripheral insulin treatment on appetite in chicks. Six-d-age chicks with ad libitum feeding or fasting for 3 h before injection received a subcutaneous injection of 0, 1, 3, 5, 10, or 20 IU of insulin or vehicle (saline). The results showed peripheral insulin treatment (1 to 20 IU) did not alter significantly the feed intake in chicks under either ad libitum feeding or fasting conditions within 4 h (p>0.05). Compared with the control, plasma glucose concentration was significantly decreased after insulin treatment of 3, 5, 10, and 20 IU for 4 h in chicks with ad libitum feeding (p<0.05). In fasted chicks, 10 and 20 IU insulin treatments significantly decreased the plasma glucose level for 4 h (p<0.05). Peripheral insulin treatment of 10 IU for 2 or 4 h did not significantly affect the hypothalamic genes expression of neuropeptide Y, proopiomelanocortin, corticotropin-releasing factor and insulin receptors (p>0.05). All results suggest peripheral administration of insulin has no effect on appetite in chicks. PMID:26954230

  16. Peripheral Insulin Doesn’t Alter Appetite of Broiler Chicks

    PubMed Central

    Liu, Lei; Xu, Shaohua; Wang, Xiaojuan; Jiao, Hongchao; Lin, Hai

    2016-01-01

    An experiment was conducted to investigate the effect of peripheral insulin treatment on appetite in chicks. Six-d-age chicks with ad libitum feeding or fasting for 3 h before injection received a subcutaneous injection of 0, 1, 3, 5, 10, or 20 IU of insulin or vehicle (saline). The results showed peripheral insulin treatment (1 to 20 IU) did not alter significantly the feed intake in chicks under either ad libitum feeding or fasting conditions within 4 h (p>0.05). Compared with the control, plasma glucose concentration was significantly decreased after insulin treatment of 3, 5, 10, and 20 IU for 4 h in chicks with ad libitum feeding (p<0.05). In fasted chicks, 10 and 20 IU insulin treatments significantly decreased the plasma glucose level for 4 h (p<0.05). Peripheral insulin treatment of 10 IU for 2 or 4 h did not significantly affect the hypothalamic genes expression of neuropeptide Y, proopiomelanocortin, corticotropin-releasing factor and insulin receptors (p>0.05). All results suggest peripheral administration of insulin has no effect on appetite in chicks. PMID:26954230

  17. Ethics for embryos.

    PubMed

    Parker, C

    2007-10-01

    This paper responds to DW Brock's technically strong case for the use of human embryonic stem cells in medical research. His main issue in this context is the question of whether it is moral to destroy viable human embryos. He offers a number of reasons to support his view that it is moral to destroy them, but his use of conceptual arguments is not adequate to secure his position. The purpose and scope of this paper is wholly concerned with his arguments rather than with the conclusion that it is justifiable to destroy human embryos. The author proceeds through his variety of arguments and offers reasons for rejecting them. The author concludes that Brock has not shown that it is moral to destroy viable human embryos.

  18. West nile virus in American white pelican chicks: transmission, immunity, and survival

    USGS Publications Warehouse

    Sovada, Marsha A.; Pietz, Pamela J.; Hofmeister, Erik K.; Bartos, Alisa J.

    2013-01-01

    West Nile virus (WNV) causes significant mortality of American White Pelican chicks at northern plains colonies. We tested oropharyngeal/cloacal swabs from moribund chicks for shed WNV. Such shedding could enable chick-to-chick transmission and help explain why WNV spreads rapidly in colonies. WNV was detected on swabs from 11% of chicks in 2006 and 52% of chicks in 2007; however, viral titers were low. Before onset of WNV mortality, we tested blood from < 3-week-old chicks for antibodies to WNV; 5% of chicks were seropositive, suggesting passive transfer of maternal antibodies. Among near-fledged chicks, 41% tested positive for anti-WNV antibodies, indicating that they survived infection. Among years and colonies, cumulative incidence of WNV in chicks varied from 28% to 81%, whereas the proportion of chicks surviving WNV (i.e., seropositive) was 64–75%. Our data revealed that WNV kills chicks that likely would fledge in the absence of WNV, that infection of chicks is pervasive, and that significant numbers of chicks survive infection.

  19. Alcohol-induced cell death in the embryo.

    PubMed

    Smith, S M

    1997-01-01

    Exposure to alcohol during gestation can have profound consequences, but not all cells within the embryo are affected equally. Recent advances in molecular embryology have allowed an exploration of this variation. Much of this research has focused on the embryo's vulnerability to the facial malformations characteristic of fetal alcohol syndrome. Studies using mice and chicks show that alcohol exposure at specific stages of early embryo development results in significant death among the cells destined to give rise to facial structures (i.e., cranial neural crest cells). This type of cell death is through activation of the cell's own "self-destruct" machinery (i.e., apoptosis). Researchers have advanced several theories to explain how alcohol triggers apoptosis in the neural crest cells. These theories include deficiency in a type of vitamin A compound, retinoic acid; reduced levels of antioxidant compounds (i.e., free radical scavengers) that protect against damage from toxic oxygen molecules (i.e., free radicals); and interference with the cell's normal internal communication pathways. PMID:15706739

  20. Teratogenic efects of injected methylmercury on avian embryos

    USGS Publications Warehouse

    Heinz, Gary H.; Hoffman, David J.; Klimstra, Jon D.; Stebbins, Katherine R.; Kondrad, Shannon L.; Erwin, Carol A.

    2011-01-01

    Controlled laboratory studies with game farm mallards (Anas platyrhynchos) and chickens (Gallus gallus) have demonstrated that methylmercury can cause teratogenic effects in birds, but studies with wild species of birds are lacking. To address this need, doses of methylmercury chloride were injected into the eggs of 25 species of birds, and the dead embryos and hatched chicks were examined for external deformities. When data for controls were summed across all 25 species tested and across all types of deformities, 24 individuals out of a total of 1,533 (a rate of 1.57%) exhibited at least one deformity. In contrast, when data for all of the mercury treatments and all 25 species were summed, 188 deformed individuals out of a total of 2,292 (8.20%) were found. Some deformities, such as lordosis and scoliosis (twisting of the spine), misshapen heads, shortening or twisting of the neck, and deformities of the wings, were seldom observed in controls but occurred in much greater frequency in Hg-treated individuals. Only 0.59% of individual control dead embryos and hatchlings exhibited multiple deformities versus 3.18% for Hg-dosed dead embryos and hatchlings. Methylmercury seems to have a widespread teratogenic potential across many species of birds.

  1. Regeneration inducers in limb regeneration.

    PubMed

    Satoh, Akira; Mitogawa, Kazumasa; Makanae, Aki

    2015-08-01

    Limb regeneration ability, which can be observed in amphibians, has been investigated as a representative phenomenon of organ regeneration. Recently, an alternative experimental system called the accessory limb model was developed to investigate early regulation of amphibian limb regeneration. The accessory limb model contributed to identification of limb regeneration inducers in urodele amphibians. Furthermore, the accessory limb model may be applied to other species to explore universality of regeneration mechanisms. This review aims to connect the insights recently gained to emboss universality of regeneration mechanisms among species. The defined molecules (BMP7 (or2) + FGF2 + FGF8) can transform skin wound healing to organ (limb) regeneration responses. The same molecules can initiate regeneration responses in some species. PMID:26100345

  2. The First Human Cloned Embryo.

    ERIC Educational Resources Information Center

    Cibelli, Jose B.; Lanza, Robert P.; West, Michael D.; Ezzell, Carol

    2002-01-01

    Describes a process known as parthenogenesis which produces cloned, early-stage embryos and human embryos generated only from eggs. Speculates that this technology puts therapeutic cloning within reach. (DDR)

  3. Sunrise, Earth Limb

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This sunrise scene (5.5S, 29.5E) was taken early in the morning, when the sun was still below the horizon and not yet illuminating the dark band of low level clouds on the Earth limb. Ranging from 13 to 18 km. above these low level clouds is a brown layer at the tropopause, an atmospheric temperature inversion which isolates the troposphere from the stratosphere and effectively concentrates particulates from both above and below this level.

  4. The mRNA expression of amino acid transporters, aminopeptidase N, and the di- and tri- peptide transporter PepT1 in the embryo of the domesticated chicken (Gallus gallus) shows developmental regulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mRNA expression profile for ten amino acid transporters (AAT), the di-and tri- peptide transporter (Pept1), and aminopeptidase N (APN) during chick embryogenesis was determined. Fertilized eggs were sampled at days 9, 11, 15, 17, 19, and 20, post fertilization. Three to four embryos were sampl...

  5. The Virtual Embryo Project

    EPA Science Inventory

    The v-Embryo™ is a far reaching new research program at the US EPA to develop a working computer model of a mammalian embryo that can be used to better understand the prenatal risks posed by environmental chemicals and to eventually predict a chemical’s potential developmental to...

  6. Embryo Aggregation in Pig Improves Cloning Efficiency and Embryo Quality.

    PubMed

    Buemo, Carla Paola; Gambini, Andrés; Moro, Lucia Natalia; Hiriart, María Inés; Fernández-Martín, Rafael; Collas, Philippe; Salamone, Daniel Felipe

    2016-01-01

    In this study, we analyzed the effects of the cloned embryo aggregation on in vitro embryo development and embryo quality by measuring blastocyst diameter and cell number, DNA fragmentation levels and the expression of genes associated with pluripotency, apoptosis, trophoblast and DNA methylation in the porcine. Zona-free reconstructed cloned embryos were cultured in the well of the well system, placing one (1x non aggregated group) or three (3x group) embryos per microwell. Our results showed that aggregation of three embryos increased blastocyst formation rate and blastocyst diameter of cloned pig embryos. DNA fragmentation levels in 3x aggregated cloned blastocysts were significantly decreased compared to 1x blastocysts. Levels of Oct4, Klf4, Igf2, Bax and Dnmt 1 transcripts were significantly higher in aggregated embryos, whereas Nanog levels were not affected. Transcripts of Cdx2 and Bcl-xl were essentially non-detectable. Our study suggests that embryo aggregation in the porcine may be beneficial for cloned embryo development and embryo quality, through a reduction in apoptotic levels and an improvement in cell reprogramming.

  7. Embryo Aggregation in Pig Improves Cloning Efficiency and Embryo Quality

    PubMed Central

    Buemo, Carla Paola; Gambini, Andrés; Moro, Lucia Natalia; Hiriart, María Inés; Fernández-Martín, Rafael; Collas, Philippe; Salamone, Daniel Felipe

    2016-01-01

    In this study, we analyzed the effects of the cloned embryo aggregation on in vitro embryo development and embryo quality by measuring blastocyst diameter and cell number, DNA fragmentation levels and the expression of genes associated with pluripotency, apoptosis, trophoblast and DNA methylation in the porcine. Zona-free reconstructed cloned embryos were cultured in the well of the well system, placing one (1x non aggregated group) or three (3x group) embryos per microwell. Our results showed that aggregation of three embryos increased blastocyst formation rate and blastocyst diameter of cloned pig embryos. DNA fragmentation levels in 3x aggregated cloned blastocysts were significantly decreased compared to 1x blastocysts. Levels of Oct4, Klf4, Igf2, Bax and Dnmt 1 transcripts were significantly higher in aggregated embryos, whereas Nanog levels were not affected. Transcripts of Cdx2 and Bcl-xl were essentially non-detectable. Our study suggests that embryo aggregation in the porcine may be beneficial for cloned embryo development and embryo quality, through a reduction in apoptotic levels and an improvement in cell reprogramming. PMID:26894831

  8. Embryo Aggregation in Pig Improves Cloning Efficiency and Embryo Quality.

    PubMed

    Buemo, Carla Paola; Gambini, Andrés; Moro, Lucia Natalia; Hiriart, María Inés; Fernández-Martín, Rafael; Collas, Philippe; Salamone, Daniel Felipe

    2016-01-01

    In this study, we analyzed the effects of the cloned embryo aggregation on in vitro embryo development and embryo quality by measuring blastocyst diameter and cell number, DNA fragmentation levels and the expression of genes associated with pluripotency, apoptosis, trophoblast and DNA methylation in the porcine. Zona-free reconstructed cloned embryos were cultured in the well of the well system, placing one (1x non aggregated group) or three (3x group) embryos per microwell. Our results showed that aggregation of three embryos increased blastocyst formation rate and blastocyst diameter of cloned pig embryos. DNA fragmentation levels in 3x aggregated cloned blastocysts were significantly decreased compared to 1x blastocysts. Levels of Oct4, Klf4, Igf2, Bax and Dnmt 1 transcripts were significantly higher in aggregated embryos, whereas Nanog levels were not affected. Transcripts of Cdx2 and Bcl-xl were essentially non-detectable. Our study suggests that embryo aggregation in the porcine may be beneficial for cloned embryo development and embryo quality, through a reduction in apoptotic levels and an improvement in cell reprogramming. PMID:26894831

  9. Regulation of chick early B-cell factor-1 gene expression in feather development.

    PubMed

    El-Magd, Mohammed Abu; Sayed-Ahmed, Ahmed; Awad, Ashraf; Shukry, Mustafa

    2014-05-01

    The chick Ebf1 (early B-cell factor-1) gene is a member of a novel family of helix loop helix transcription factors. The expression profile, regulation and significance of this gene have been extensively studied in lymphatic, nervous, adipose and muscular tissues. However, cEbf1 expression, regulation and function in the feather of chick embryo have not yet been investigated. cEbf1 expression was first detected throughout the mesenchymal core of some few feather placodes (D7-D7.5). After feathers became mature and grew distally (D9 and D10), the mesenchymal expression of cEbf1 became confined to the caudal margin of the proximal half of all formed feather buds. Because this dynamic pattern of expression resembles that of Sonic Hedgehog (Shh) protein and bone morphogenetic protein (Bmp4) plus the crucial role of these two major signals in feather development, we hypothesized that cEbf1 expression in the feather may be regulated by Shh and Bmp4. In a feather explant culture system, Shh signals are necessary to initiate and maintain cEbf1 expression in the posterior half of the feather bud, while Bmp4 is crucial for the initial cEbf1 expression in the anterior half of the feather bud. Inhibition of Shh, not only down-regulates cEbf1, but also changes the morphology of feather buds, which become irregular and fused. This is the first study to demonstrate that cEbf1 expression in the feather bud is under the control of Shh and Bmp4 signals and that expression may play a role in the normal development of feathers.

  10. Light-dependent development of asymmetry in the ipsilateral and contralateral thalamofugal visual projections of the chick.

    PubMed

    Koshiba, Mamiko; Nakamura, Shun; Deng, Chao; Rogers, Lesley J

    2003-01-16

    Light-exposure of the chick embryo induces development of asymmetry in the thalamofugal visual projections to the Wulst regions of the forebrain since the embryo is turned so that it occludes its left and not its right eye. This asymmetry can be reversed by occluding the embryo's right eye and exposing its left eye to light. Here we show that three sub-regions of the thalamus (two in the dorsolateral anterior thalami (DLA) and one more caudal) have differing asymmetries of contralateral and/or ipsilateral projections. Hence the effect of asymmetrical light stimulation is regionally specific within the thalamus. Lateralised light stimulation appears to promote the development of ipsilateral projections from DLA pars dorsolateralis pars anterioris and contralateral projections from the caudal regions (the nucleus superficialis parvocellularis especially) but it may suppress the development of contralateral projections from the nucleus dorsolateralis anterior thalami pars lateralis rostralis. We also show that the light stimulation causes lateralised expression of c-fos and receptors for neurotransmitters. PMID:12499045

  11. A reevaluation of X-irradiation-induced phocomelia and proximodistal limb patterning.

    PubMed

    Galloway, Jenna L; Delgado, Irene; Ros, Maria A; Tabin, Clifford J

    2009-07-16

    Phocomelia is a devastating, rare congenital limb malformation in which the long bones are shorter than normal, with the upper portion of the limb being most severely affected. In extreme cases, the hands or fingers are attached directly to the shoulder and the most proximal elements (those closest to the shoulder) are entirely missing. This disorder, previously known in both autosomal recessive and sporadic forms, showed a marked increase in incidence in the early 1960s due to the tragic toxicological effects of the drug thalidomide, which had been prescribed as a mild sedative. This human birth defect is mimicked in developing chick limb buds exposed to X-irradiation. Both X-irradiation and thalidomide-induced phocomelia have been interpreted as patterning defects in the context of the progress zone model, which states that a cell's proximodistal identity is determined by the length of time spent in a distal limb region termed the 'progress zone'. Indeed, studies of X-irradiation-induced phocomelia have served as one of the two major experimental lines of evidence supporting the validity of the progress zone model. Here, using a combination of molecular analysis and lineage tracing in chick, we show that X-irradiation-induced phocomelia is fundamentally not a patterning defect, but rather results from a time-dependent loss of skeletal progenitors. Because skeletal condensation proceeds from the shoulder to fingers (in a proximal to distal direction), the proximal elements are differentially affected in limb buds exposed to radiation at early stages. This conclusion changes the framework for considering the effect of thalidomide and other forms of phocomelia, suggesting the possibility that the aetiology lies not in a defect in the patterning process, but rather in progenitor cell survival and differentiation. Moreover, molecular evidence that proximodistal patterning is unaffected after X-irradiation does not support the predictions of the progress zone model.

  12. The chick chorioallantoic membrane as an in vivo xenograft model for Burkitt lymphoma

    PubMed Central

    2014-01-01

    Background Burkitt lymphoma (BL) is an aggressive malignancy that arises from B-cells and belongs to the group of Non-Hodgkin lymphomas (NHL). Due to the lack of appropriate in vivo models NHL research is mainly performed in vitro. Here, we studied the use of the chick chorioallantoic membrane (CAM) for the generation of human BL xenograft tumors, which we compared with known characteristics of the human disease. Methods In order to generate experimental BL tumors, we inoculated human BL2B95 and BL2-GFP cells on the CAM. BL2B95 xenograft-tumors were grown for seven days and subsequently analyzed with transmission electron and immunofluorescence microscopy, as well as histological staining approaches. BL2-GFP cells were studied at regular intervals up to seven days, and their metastatic behavior was visualized with intravital immunofluorescence techniques. Results Xenografted BL2B95 cells formed solid tumors in the CAM model with a Ki67-index greater than 90%, preservation of typical tumor markers (CD10, CD19, CD20), a ‘starry sky’ morphology, production of agyrophilic fibers in the stroma, formation of blood and lymphatic vessels and lymphogenic dissemination of BL2B95 to distant sites. We identified macrophages, lymphocytes and heterophilic granulocytes (chick homolog of neutrophils) as the most abundant immune cells in the experimental tumors. BL2-GFP cells could be traced in real-time during their distribution in the CAM, and the first signs for their dissemination were visible after 2-3 days. Conclusions We show that xenografted BL2B95 cells generate tumors in the CAM with a high degree of cellular, molecular and proliferative concord with the human disease, supporting the application of the CAM model for NHL research with a focus on tumor-stroma interactions. Additionally we report that BL2-GFP cells, grafted on the CAM of ex ovo cultured chick embryos, provide a powerful tool to study lymphogenic dissemination in real-time. PMID:24884418

  13. Proximal to distal patterning during limb development and regeneration: a review of converging disciplines.

    PubMed

    Mariani, Francesca V

    2010-05-01

    Regeneration of lost structures typically involves distinct events: wound healing at the damaged site, the accumulation of cells that will be used as future building blocks and, finally, the initiation of molecular signaling pathways that dictate the form and pattern of the regenerated structures. Amphibians and urodeles in particular, have long been known to have exceptional regenerative properties. For many years, these animals have been the model of choice for understanding limb regeneration, a complex process that involves reconstructing skin, muscle, bone, connective tissue and nerves into a functional 3D structure. It appears that this process of rebuilding an adult limb has many similarities with how the limb forms in the first place--for example, in the embryo, all the components of the limb need to be formed and this requires signaling mechanisms to specify the final pattern. Thus, both limb formation and limb regeneration are likely to employ the same molecular pathways. Given the available tools of molecular biology and genetics, this is an exciting time for both fields to share findings and make significant progress in understanding more about the events that dictate embryonic limb pattern and control limb regeneration. This article focuses particularly on what is known about the molecular control of patterning along the proximal-distal axis. PMID:20455655

  14. Anemia induced by high zinc intake in chicks: Mechanisms

    SciTech Connect

    Pimentel, J.L.; Greger, J.L.; Cook, M.E. )

    1991-03-15

    The mechanisms by which excess Zn induced anemia in chickens was assessed in 8 studies in which chicks were randomly assigned to a 2 {times} 2 factorial arrangement of treatments with 60 or 2,000 {mu}g Zn and 10 or 250 {mu}g Cu/g diet. Less Fe-59 appeared in the plasma 1 hour after a labeled meal when chicks were fed excess Zn in 1 of 2 studies but less Fe-59 appeared in livers of chicks fed excess Zn in both studies. The decrease of Fe-59 uptake into tissues paralleled a decrease in Fe concentrations in livers and tibiotarsi. These differences in tissue Fe did not reflect differences in Fe excretion because excretion and incorporation into tissues of injected Fe-59 was not affected by high Zn intake. Although excess Zn decreased tissue Cu concentrations, excess Zn, per se, did not affect cytosolic superoxide dismutase activity, the in vivo t 1/2 of erythrocytes, or erythrocyte hemolysis in vitro. The decrease in body weight of chicks fed excess Zn indicated that protein synthesis and/or degradation could be affected. Increased incorporation of C-14 tyrosine into liver and bone marrow of chicks fed excess Zn suggested increased protoporphyrin synthesis or metallothionein synthesis. These results indicated that decreased Fe absorption was the primary mechanism by which excess Zn induced anemia.

  15. Ontogeny of thermoregulatory mechanisms in king penguin chicks (Aptenodytes patagonicus).

    PubMed

    Duchamp, Claude; Rouanet, Jean Louis; Barré, Hervé

    2002-04-01

    The rapid maturation of thermoregulatory mechanisms may be of critical importance for optimising chick growth and survival and parental energy investment under harsh climatic conditions. The ontogeny of thermoregulatory mechanisms was studied in growing king penguin chicks from hatching to the full emancipation observed at 1 month of age in the sub-Antarctic area (Crozet Archipelago). Newly hatched chicks showed small, but significant regulatory thermogenesis (21% rise in heat production assessed by indirect calorimetry), but rapidly became hypothermic. Within a few days, both resting (+32%) and peak (+52%) metabolic rates increased. The first week of life was characterised by a two-fold rise in thermogenic capacity in the cold, while thermal insulation was not improved. During the second and third weeks of age, thermal insulation markedly rose (two-fold drop in thermal conductance) in relation to down growth, while resting heat production was slightly reduced (-13%). Shivering (assessed by electromyography) was visible right after hatching, although its efficiency was limited. Thermogenic efficiency of shivering increased five-fold with age during the first weeks of life, but there was no sign of non-shivering thermogenesis. We conclude that thermal emancipation of king penguin chicks may be primarily determined by improvement of thermal insulation after thermogenic processes have become sufficiently matured. Both insulative and metabolic adaptations are required for the rapid ontogeny of thermoregulation and thermal emancipation in growing king penguin chicks. PMID:11897187

  16. Identification of spontaneous mutations within the long-range limb-specific Sonic Hedgehog enhancer (ZRS) that alter Sonic Hedgehog expression in the chicken limb mutants oligozeugodactly and Silkie Breed

    PubMed Central

    Maas, Sarah A.; Suzuki, Takayuki; Fallon, John F.

    2011-01-01

    The evolutionarily conserved, non-coding ~800 base-pair zone of polarizing activity (ZPA) regulatory sequence (ZRS) controls Shh expression in the posterior limb. We report that the chicken mutant oligozeugodactly (ozd), which lacks limb Shh expression, has a large deletion within the ZRS. Furthermore, the preaxial polydactylous, Silkie Breed chicken, which develops ectopic anterior limb Shh expression, has a single base-pair change within the ZRS. Using an in vivo reporter assay to examine enhancer function in the chick limb, we demonstrate that the wild-type ZRS drives β-galactosidase reporter expression in the ZPA of both wild-type and ozd limbs. The Silkie ZRS drives β-galactosidase in both posterior and anterior Shh domains in wild-type limb buds. These results support the hypothesis that the ZRS integrates positive and negative prepatterned regulatory inputs in the chicken model system and demonstrate the utility of the chicken limb as an efficient genetic system for gene regulatory studies. PMID:21509895

  17. Limb lengthening in achondroplasia

    PubMed Central

    Chilbule, Sanjay K; Dutt, Vivek; Madhuri, Vrisha

    2016-01-01

    Background: Stature lengthening in skeletal dysplasia is a contentious issue. Specific guidelines regarding the age and sequence of surgery, methods and extent of lengthening at each stage are not uniform around the world. Despite the need for multiple surgeries, with their attendant complications, parents demanding stature lengthening are not rare, due to the social bias and psychological effects experienced by these patients. This study describes the outcome and complications of extensive stature lengthening performed at our center. Materials and Methods: Eight achondroplasic and one hypochondroplasic patient underwent bilateral transverse lengthening for tibiae, humeri and femora. Tibia lengthening was carried out using a ring fixator and bifocal corticotomy, while a monolateral pediatric limb reconstruction system with unifocal corticotomy was used for the femur and humerus. Lengthening of each bone segment, height gain, healing index and complications were assessed. Subgroup analysis was carried out to assess the effect of age and bone segment on the healing index. Results: Nine patients aged five to 25 years (mean age 10.2 years) underwent limb lengthening procedures for 18 tibiae, 10 femora and 8 humeri. Four patients underwent bilateral lengthening of all three segments. The mean length gain for the tibia, femur and humerus was 15.4 cm (100.7%), 9.9 cm (52.8%) and 9.6 cm (77.9%), respectively. Healing index was 25.7, 25.6 and 20.6 days/cm, respectively, for the tibia, femur and humerus. An average of 33.3% height gain was attained. Lengthening of both tibia and femur added to projected height achieved as the 3rd percentile of standard height in three out of four patients. In all, 33 complications were encountered (0.9 complications per segment). Healing index was not affected by age or bone segment. Conclusion: Extensive limb lengthening (more than 50% over initial length) carries significant risk and should be undertaken only after due consideration. PMID

  18. Lipotyphla limb myology comparison.

    PubMed

    Neveu, Pauline; Gasc, Jean-Pierre

    2002-05-01

    Fore- and hindlimb muscles were dissected in four species of Lipotyphla: the western European hedgehog Erinaceus europaeus (Erinaceidae, Erinaceinae); the moonrat Echinosorex gymnura (Erinaceidae, Hylomyinae or Galericinae); the tailless tenrec Tenrec ecaudatus (Tenrecidae, Tenrecinae); and the common European white-toothed shrew Crocidura russula (Soricidae, Soricinae). This work completely reviews the limb musculature of these walking mammals. Twelve myological characters were evaluated in order to disclose phylogenetic relationships. The cladogram obtained supported previous ones based on cranial and dental characters. This study shows that myological characters are valuable in phylogenetic analyses.

  19. GATA6 Is a Crucial Regulator of Shh in the Limb Bud

    PubMed Central

    Kozhemyakina, Elena; Ionescu, Andreia; Lassar, Andrew B.

    2014-01-01

    In the limb bud, patterning along the anterior-posterior (A-P) axis is controlled by Sonic Hedgehog (Shh), a signaling molecule secreted by the “Zone of Polarizing Activity”, an organizer tissue located in the posterior margin of the limb bud. We have found that the transcription factors GATA4 and GATA6, which are key regulators of cell identity, are expressed in an anterior to posterior gradient in the early limb bud, raising the possibility that GATA transcription factors may play an additional role in patterning this tissue. While both GATA4 and GATA6 are expressed in an A-P gradient in the forelimb buds, the hindlimb buds principally express GATA6 in an A-P gradient. Thus, to specifically examine the role of GATA6 in limb patterning we generated Prx1-Cre; GATA6fl/fl mice, which conditionally delete GATA6 from their developing limb buds. We found that these animals display ectopic expression of both Shh and its transcriptional targets specifically in the anterior mesenchyme of the hindlimb buds. Loss of GATA6 in the developing limbs results in the formation of preaxial polydactyly in the hindlimbs. Conversely, forced expression of GATA6 throughout the limb bud represses expression of Shh and results in hypomorphic limbs. We have found that GATA6 can bind to chromatin (isolated from limb buds) encoding either Shh or Gli1 regulatory elements that drive expression of these genes in this tissue, and demonstrated that GATA6 works synergistically with FOG co-factors to repress expression of luciferase reporters driven by these sequences. Most significantly, we have found that conditional loss of Shh in limb buds lacking GATA6 prevents development of hindlimb polydactyly in these compound mutant embryos, indicating that GATA6 expression in the anterior region of the limb bud blocks hindlimb polydactyly by repressing ectopic expression of Shh. PMID:24415953

  20. Causes of mortality of albatross chicks at Midway Atoll

    USGS Publications Warehouse

    Sileo, L.; Sievert, P.R.; Samuel, M.D.

    1990-01-01

    As part of an investigation of the effect of plastic ingestion on seabirds in Hawaii, we necropsied the carcasses of 137 Laysan albatross (Diomedea immutabilis) chicks from Midway Atoll in the Pacific Ocean during the summer of 1987. Selected tissues were collected for microbiological, parasitological, toxicological or histopathological examinations. Dehydration was the most common cause of death. Lead poisoning, trauma, emaciation (starvation) and trombidiosis were other causes of death; nonfatal nocardiosis and avian pox also were present. There was no evidence that ingested plastic caused mechanical lesions or mortality in 1987, but most of the chicks had considerably less plastic in them than chicks from earlier years. Human activity (lead poisoning and vehicular trauma) caused mortality at Midway Atoll and represented additive mortality for pre-fledgling albatrosses.

  1. Memantine improves observational learning in day-old chicks.

    PubMed

    Barber, Teresa A; Kimbrough, Tiffany N

    2015-06-01

    Evidence of observational learning (social learning) is present in many species. One such task is the one-trial taste-avoidance task, in which Actor chicks peck a bead coated with an aversant substance. Observer chicks learn to avoid beads that are similar in appearance to the one presented to the Actors. It has been firmly established that active learning of the one-trial taste-avoidance task is dependent on a constrained level of glutamate receptor activation. The current study examined the effects of memantine, a noncompetitive N-methyl-D-aspartate receptor antagonist, on the learning by Observers. Memantine produced an inverted U-shaped dose-dependent response curve; 1.0 mmol/l memantine produced significant improvement. These results demonstrate that memantine influences memory formation for observational learning in the day-old chick and support the hypothesis that memantine can improve memories by altering levels of glutamate during memory formation.

  2. Making sense-data-based simulations of vertebrate limb development.

    PubMed

    Iber, Dagmar; Zeller, Rolf

    2012-12-01

    Limb bud development has been studied for decades and contributed a wealth of knowledge to our understanding of the molecular and cellular mechanisms that govern organogenesis in vertebrate embryos. However, the general regulatory paradigms that underlie the functional and structural organization of complex systems such as developing limb buds have remained largely elusive. A significant number of mathematical theories have been proposed to explain these developmental processes, but have rarely been validated by experimental analysis. In the age of systems biology, experimental and mathematical approaches have become interlinked and enable the experimental validation of computational models by molecular and genetic analysis. This in turn allows refinement of the mathematical simulations such that simulating limb bud development becomes increasingly more realistic. The resulting models not only detect inconsistencies in the interpretation of experimental data, but their predictive power facilitates identification of key regulatory interactions and definition of so-called core and accessory mechanisms. The ongoing integrative analysis of vertebrate limb organogenesis indicates that these network simulations may be suitable for in silico genetics, that is the computational modeling of complex loss-of-functions and gain-of-functions states. Such in silico genetic approaches will permit the simulation of complex mutant phenotypes tedious or impossible to generate using mouse molecular genetics. PMID:23266216

  3. Carbonic anhydrases in chick extra-embryonic structures: a role for CA in bicarbonate reabsorption through the chorioallantoic membrane.

    PubMed

    Gabrielli, M Gabriella

    2004-06-01

    The villus cavity cells, a specific cell type of the chick chorioallantoic membrane, express both cytosolic carbonic anhydrase in their cytoplasm and HCO3(-)/Cl(-) anion exchangers at their basolateral membranes. By immunohistochemical analysis, we show here that villus cavity cells specifically react with antibodies directed against the membrane-associated form of carbonic anhydrase, CAIV. Staining is restricted to the apical cell membranes, characteristically invaginated toward the shell membrane, as well as to endothelia of blood vessels present in the mesodermal layer. The occurrence of a membrane-associated CA form at the apical pole of villus cavity cells, when definitively confirmed, would be fairly consistent with the role proposed for these cells in bicarbonate reabsorption from the eggshell so to prevent metabolic acidosis in the embryo during development.

  4. Expression and Function of Ccbe1 in the Chick Early Cardiogenic Regions Are Required for Correct Heart Development

    PubMed Central

    Correia, Elizabeth; Inácio, José Manuel; Belo, José António

    2014-01-01

    During the course of a differential screen to identify transcripts specific for chick heart/hemangioblast precursor cells, we have identified Ccbe1 (Collagen and calcium-binding EGF-like domain 1). While the importance of Ccbe1 for the development of the lymphatic system is now well demonstrated, its role in cardiac formation remained unknown. Here we show by whole-mount in situ hybridization analysis that cCcbe1 mRNA is initially detected in early cardiac progenitors of the two bilateral cardiogenic fields (HH4), and at later stages on the second heart field (HH9-18). Furthermore, cCcbe1 is expressed in multipotent and highly proliferative cardiac progenitors. We characterized the role of cCcbe1 during early cardiogenesis by performing functional studies. Upon morpholino-induced cCcbe1 knockdown, the chick embryos displayed heart malformations, which include aberrant fusion of the heart fields, leading to incomplete terminal differentiation of the cardiomyocytes. cCcbe1 overexpression also resulted in severe heart defects, including cardia bifida. Altogether, our data demonstrate that although cardiac progenitors cells are specified in cCcbe1 morphants, the migration and proliferation of cardiac precursors cells are impaired, suggesting that cCcbe1 is a key gene during early heart development. PMID:25545279

  5. Thioredoxin-2 Modulates Neuronal Programmed Cell Death in the Embryonic Chick Spinal Cord in Basal and Target-Deprived Conditions

    PubMed Central

    Pirson, Marc; Debrulle, Stéphanie; Clippe, André; Clotman, Frédéric; Knoops, Bernard

    2015-01-01

    Thioredoxin-2 (Trx2) is a mitochondrial protein using a dithiol active site to reduce protein disulfides. In addition to the cytoprotective function of this enzyme, several studies have highlighted the implication of Trx2 in cellular signaling events. In particular, growing evidence points to such roles of redox enzymes in developmental processes taking place in the central nervous system. Here, we investigate the potential implication of Trx2 in embryonic development of chick spinal cord. To this end, we first studied the distribution of the enzyme in this tissue and report strong expression of Trx2 in chick embryo post-mitotic neurons at E4.5 and in motor neurons at E6.5. Using in ovo electroporation, we go on to highlight a cytoprotective effect of Trx2 on the programmed cell death (PCD) of neurons during spinal cord development and in a novel cultured spinal cord explant model. These findings suggest an implication of Trx2 in the modulation of developmental PCD of neurons during embryonic development of the spinal cord, possibly through redox regulation mechanisms. PMID:26540198

  6. Molecular anatomy of the developing limb in the coquí frog, Eleutherodactylus coqui Limb bud development in the coquí frog

    PubMed Central

    Gross, Joshua B; Kerney, Ryan; Hanken, James; Tabin, Clifford J

    2011-01-01

    The vertebrate limb demonstrates remarkable similarity in basic organization across phylogenetically disparate groups. To gain further insight into how this morphological similarity is maintained in different developmental contexts, we explored the molecular anatomy of size-reduced embryos of the Puerto Rican coquí frog, Eleutherodactylus coqui. This animal demonstrates direct development, a life history strategy marked by rapid progression from egg to adult and absence of a free-living, aquatic larva. Nonetheless, coquí exhibits a basal anuran limb structure, with four toes on the forelimb and five toes on the hind limb. We investigated the extent to which coquí limb bud development conforms to the model of limb development derived from amniote studies. Towards this end, we characterized dynamic patterns of expression for 13 critical patterning genes across three principle stages of limb development. As expected, most genes demonstrate expression patterns that are essentially unchanged compared to amniote species. For example, we identified an EcFgf8-expression domain within the apical ectodermal ridge (AER). This expression pattern defines a putatively functional AER signalling domain, despite the absence of a morphological ridge in coquí embryos. However, two genes, EcMeis2 and EcAlx4, demonstrate altered domains of expression, which imply a potential shift in gene function between coquí frogs and amniote model systems. Unexpectedly, several genes thought to be critical for limb patterning in other systems, including EcFgf4, EcWnt3a, EcWnt7a and EcGremlin, demonstrated no evident expression pattern in the limb at the three stages we analyzed. The absence of EcFgf4 and EcWnt3a expression during limb patterning is perhaps not surprising, given that neither gene is critical for proper limb development in the mouse, based on knock-out and expression analyses. In contrast, absence of EcWnt7a and EcGremlin is surprising, given that expression of these molecules

  7. Immature embryo rescue and culture.

    PubMed

    Shen, Xiuli; Gmitter, Fred G; Grosser, Jude W

    2011-01-01

    Embryo culture techniques have many significant applications in plant breeding, as well as basic studies in physiology and biochemistry. Immature embryo rescue and culture is a particularly attractive technique for recovering plants from sexual crosses where the majority of embryos cannot survive in vivo or become dormant for long periods of time. Overcoming embryo inviability is the most common reason for the application of embryo rescue techniques. Recently, fruit breeding programs have greatly increased the interest in exploiting interploid hybridization to combine desirable genetic traits of complementary parents at the triploid level for the purpose of developing improved seedless fruits. However, the success of this approach has only been reported in limited number of species due to various crossing barriers and embryo abortion at very early stages. Thus, immature embryo rescue provides an alternative means to recover triploid hybrids, which usually fail to completely develop in vivo. This chapter will provide a brief discussion of the utilization of interploid crosses between a monoembryonic diploid female with an allotetraploid male in a citrus cultivar improvement program, featuring a clear and comprehensive illustration of successful protocols for immature embryo rescue and culture. The protocols will cover the complete process from embryo excision to recovered plant in the greenhouse and can easily be adapted to other plant commodities. Factors affecting the success and failure of immature embryo rescue to recover triploid progeny from interploid crosses will be discussed.

  8. Green Light-emitting Diodes Light Stimuli during Incubation Enhances Posthatch Growth without Disrupting Normal Eye Development of Broiler Embryos and Hatchlings

    PubMed Central

    Zhang, L.; Zhu, X. D.; Wang, X. F.; Li, J. L.; Gao, F.; Zhou, G. H.

    2016-01-01

    Monochromatic green light-emitting diodes (LED) light stimuli influences the posthatch growth performance of chicks. This study was undertaken with the following objectives: i) to examine whether the green LED light stimuli induces an overheating effect by determining weight loss rate of fertile eggs during incubation period; ii) to look for the development of eyes and other primary organs at different ages of embryos and newly hatched chicks. Arbor Acres fertile broiler eggs (n = 480) were randomly assigned to 3 incubation groups and exposed to continuous white light, green light, or a dark environment (control) from the first day to 19 d of incubation. The light sourced from LED lamps with the intensity of 30 lx at eggshell level. The results showed that either green or white light stimuli during incubation did not significantly affect the weight loss rate of fertile eggs, hatching time, hatchability, chick embryo, or body weight (BW), the weight percentage of heart, liver, and eyes, as well as obvious systematic abnormalities in eye weight, side-to-side, back-to-front, or corneal diameter from 15 d of embryogenesis to 6 d of posthatch (p>0.05). Compared with the dark condition, green light stimuli during incubation tended to increase feed intake (p = 0.080), improved the BW gain of chicks during 0 to 6 day posthatch (p<0.05), and increased the percentage of pectoral muscle to the BW on 3- and 6-day-old chicks. In addition, embryos or chicks in green light had lower weight percentage of yolk retention on 19 d of embryogenesis and 1 d of posthatch in comparison to those in dark or white group (p<0.05). These results suggest that providing 30 lx green LED light stimuli during incubation has no detrimental effect on the development of eyes, heart and liver of embryos and hatchlings, but does have potential benefits in terms of enhancement of the chick growth during the early posthatch stages. In addition, the fertile broiler eggs stimulated with 30 lx green LED

  9. Apparent Metabolizable Energy Needs of Broiler Chicks Subjected to Diverse Ambient Temperature Regimens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Early chick performance is adversely affected by inadequate ambient temperatures. Increasing AME may help alleviate poor performance with chicks subjected to low brooding temperatures. This study examined broiler chicks provided diets formulated to either 3,040 or 3,140 kcal AME/kg when subjected to...

  10. Circadian profiles in the embryonic chick heart: L-type voltage-gated calcium channels and signaling pathways.

    PubMed

    Ko, Michael L; Shi, Liheng; Grushin, Kirill; Nigussie, Fikru; Ko, Gladys Y-P

    2010-10-01

    Circadian clocks exist in the heart tissue and modulate multiple physiological events, from cardiac metabolism to contractile function and expression of circadian oscillator and metabolic-related genes. Ample evidence has demonstrated that there are endogenous circadian oscillators in adult mammalian cardiomyocytes. However, mammalian embryos cannot be entrained independently to light-dark (LD) cycles in vivo without any maternal influence, but circadian genes are well expressed and able to oscillate in embryonic stages. The authors took advantage of using chick embryos that are independent of maternal influences to investigate whether embryonic hearts could be entrained under LD cycles in ovo. The authors found circadian regulation of L-type voltage-gated calcium channels (L-VGCCs), the ion channels responsible for the production of cardiac muscle contraction in embryonic chick hearts. The mRNA levels and protein expression of VGCCα1C and VGCCα1D are under circadian control, and the average L-VGCC current density is significantly larger when cardiomyocytes are recorded during the night than day. The phosphorylation states of several kinases involved in insulin signaling and cardiac metabolism, including extracellular signal-regulated kinase (Erk), stress-activated protein kinase (p38), protein kinase B (Akt), and glycogen synthase kinase-3β (GSK-3β), are also under circadian control. Both Erk and p38 have been implicated in regulating cardiac contractility and in the development of various pathological states, such as cardiac hypertrophy and heart failure. Even though both Erk and phosphoinositide 3-kinase (PI3K)-Akt signaling pathways participate in complex cellular processes regarding physiological or pathological states of cardiomyocytes, the circadian oscillators in the heart regulate these pathways independently, and both pathways contribute to the circadian regulation of L-VGCCs.

  11. Chicken Embryos as a Potential New Model for Early Onset Type I Diabetes

    PubMed Central

    Shi, Liheng; Ko, Michael L.; Huang, Cathy Chia-Yu; Park, So-Young; Hong, Min-Pyo; Ko, Gladys Y.-P.

    2014-01-01

    Diabetic retinopathy (DR) is the leading cause of blindness among the American working population. The purpose of this study is to establish a new diabetic animal model using a cone-dominant avian species to address the distorted color vision and altered cone pathway responses in prediabetic and early diabetic patients. Chicken embryos were injected with either streptozotocin (STZ), high concentration of glucose (high-glucose), or vehicle at embryonic day 11. Cataracts occurred in varying degrees in both STZ- and high glucose-induced diabetic chick embryos at E18. Streptozotocin-diabetic chicken embryos had decreased levels of blood insulin, glucose transporter 4 (Glut4), and phosphorylated protein kinase B (pAKT). In STZ-injected E20 embryos, the ERG amplitudes of both a- and b-waves were significantly decreased, the implicit time of the a-wave was delayed, while that of the b-wave was significantly increased. Photoreceptors cultured from STZ-injected E18 embryos had a significant decrease in L-type voltage-gated calcium channel (L-VGCC) currents, which was reflected in the decreased level of L-VGCCα1D subunit in the STZ-diabetic retinas. Through these independent lines of evidence, STZ-injection was able to induce pathological conditions in the chicken embryonic retina, and it is promising to use chickens as a potential new animal model for type I diabetes. PMID:25133191

  12. An intrinsic timer specifies distal structures of the vertebrate limb

    PubMed Central

    Saiz-Lopez, Patricia; Chinnaiya, Kavitha; Campa, Victor M.; Delgado, Irene; Ros, Maria A.; Towers, Matthew

    2015-01-01

    How the positional values along the proximo-distal axis (stylopod-zeugopod-autopod) of the limb are specified is intensely debated. Early work suggested that cells intrinsically change their proximo-distal positional values by measuring time. Recently, however, it is suggested that instructive extrinsic signals from the trunk and apical ectodermal ridge specify the stylopod and zeugopod/autopod, respectively. Here, we show that the zeugopod and autopod are specified by an intrinsic timing mechanism. By grafting green fluorescent protein-expressing cells from early to late chick wing buds, we demonstrate that distal mesenchyme cells intrinsically time Hoxa13 expression, cell cycle parameters and the duration of the overlying apical ectodermal ridge. In addition, we reveal that cell affinities intrinsically change in the distal mesenchyme, which we suggest results in a gradient of positional values along the proximo-distal axis. We propose a complete model in which a switch from extrinsic signalling to intrinsic timing patterns the vertebrate limb. PMID:26381580

  13. Real protection for the embryo.

    PubMed

    Mazzoni, Cosimo Marco

    2005-01-01

    This article fundamentally analyses the current protection that the Italian law offers to the embryo. Likewise, the author, contrary to those who are of the opinion that the embryo is a person subject to law, exposes his polemic theory in which he places the embryo within the scope of things. Specifically, he argues that the embryo has a quasi-personal category. In order to justify this, he analyses the moral and legal history of the statute of the embryo, he makes a difference between the biological life and the legal life. The author establishes that the concept of the person has been and will continue to be a very controversial concept, concluding with a study on the Italian legislation in respect to the protection of the embryo.

  14. Sterilising embryos for transgenic chimaeras.

    PubMed

    Aige-Gil, V; Simkiss, K

    1991-07-01

    1. Experiments were undertaken to attempt to sterilise fowl embryos with ultraviolet light. Such sterilised embryos would be useful as recipients of genetically manipulated germ cells. 2. The germinal crescents of embryos were exposed to a calibrated UV source at stages 4 and 8 to 10 of incubation for 30 s, 3 min and 10 min. Teratological and sterility effects were studied at periods up to 6 d of incubation. 3. Simply exposing embryos by opening the shell produced a number of abnormalities and mortalities. These decreased with the age of the embryo but increased with the dosage of irradiation. 4. Although there was abundant evidence for UV-induced cell damage, the sterility of the embryos was usually less than 75%. PMID:1893258

  15. Linearity of pulsatile pressure-flow relations in the embryonic chick vascular system.

    PubMed

    Yoshigi, M; Keller, B B

    1996-10-01

    The calculation and modeling of vascular input impedance are based on the assumption that pressure and flow are linearly related in the frequency domain. However, this assumption has not been proven for the embryonic circulation. Therefore, we investigated the linearity of pulsatile pressure flow relations in vivo with acute alterations in cycle length. We simultaneously measured dorsal aortic pressure with a servonull system and flow velocity with a 20-MHz pulsed-Doppler system in stage 24 chick embryos (n = 38). Cycle length was acutely altered using thermal probe(s) applied to the sinus venosus. We determined the impedance spectra at several cycle lengths for each embryo and a reference curve from a three-element Windkessel model with the use of nonlinear curve fitting. We then assessed the scatter of experimental impedance along the reference curve as a measure of linearity in the frequency domain. We found that mean vascular resistance did not change after thermal probe applications (P > .20 for each), indicating that acute alterations in cycle length did not alter peripheral vascular properties. Superpositioned impedance spectra showed minimal scatter along the model impedance from 0 to 6 Hz. Goodness of fit values (R2) were near unity (.94 to .97) and were similar for all interventions (P > .07 for Fisher's z, by F test). Above 6 Hz, both modulus and phase spectra exhibited significant scatter (P < .05, by F test). Experimental impedance spectra tended to have a fluctuation and a phase-zero crossover, indicating significant wave reflection in the embryonic circulation. Thus, the embryonic vascular system can be approximated as a linear system from 0 to 6 Hz, the range in which the majority (96.0 +/- 0.18%) of hydraulic energy is dissipated.

  16. Outgrowth and directional specificity of fibers from embryonic retinal transplants in the chick optic tectum.

    PubMed

    Thanos, S; Dütting, D

    1987-04-01

    Retinal pieces taken from known positions of 6-day chick embryos were vitally labeled with the fluorescent dye Rhodamine-B-isothiocyanate (RITC). They were then transferred onto the surfaces of optic tecta following early bilateral removal of the embryo's optic vesicles. One to 5 days after transplantation the tecta were fixed and transplants that issued fibers were examined on tectal whole-mounts or were sectioned and viewed with a fluorescence microscope. Retinal fibers growing out from transplants on day E6 tecta showed a capacity for changing their initial outgrowth directions and for reorienting themselves towards their specific retinotopic projection area. Frequently, changes in growth direction appeared in a right-angled pattern. The capacity for turning was strongest for fibers of nasal retinal origin, less strong for fibers of temporal origin, and occurred rarely but unquantifiably in the case of fibers of ventral retinal origin. Fibers of all investigated retinal quadrants were found to reach their corresponding projection areas and to arborize there, that is, fibers of nasal retinal transplants in the posterior tectum, of temporal transplants in the anterior tectum, and of ventral transplants in the dorsal tectum. Furthermore, once in their target region, the fibers left the outer layer of the tectum and turned, again in right angles, to invade deeper layers. Capacity of fibers to turn towards their projection area was not observed for fibers issued from transplants placed on the tectum later than day E8. We suggest that there is a specific guidance of retinal axons on the tectum. PMID:3567662

  17. Evaluation of Limb-Girdle Muscular Dystrophy

    ClinicalTrials.gov

    2014-03-06

    Becker Muscular Dystrophy; Limb-Girdle Muscular Dystrophy, Type 2A (Calpain-3 Deficiency); Limb-Girdle Muscular Dystrophy, Type 2B (Miyoshi Myopathy, Dysferlin Deficiency); Limb-Girdle Muscular Dystrophy, Type 2I (FKRP-deficiency)

  18. Gender determination of avian embryo

    DOEpatents

    Daum, Keith A.; Atkinson, David A.

    2002-01-01

    Disclosed is a method for gender determination of avian embryos. During the embryo incubation process, the outer hard shells of eggs are drilled and samples of allantoic fluid are removed. The allantoic fluids are directly introduced into an ion mobility spectrometer (IMS) for analysis. The resulting spectra contain the relevant marker peaks in the positive or negative mode which correlate with unique mobilities which are sex-specific. This way, the gender of the embryo can be determined.

  19. Electrothermal branding for embryo labeling.

    PubMed

    Wang, L; Beebe, D J; Williams, A R; Easley, K D

    1997-11-01

    A novel embryo labeling technique based on electrothermal branding is developed. Two types of micro branding irons are fabricated and tested. One utilizes 25 microns tungsten wire as the heating element. The other utilizes surface micromachining techniques to fabricate polysilicon branding irons. The thermal behavior of the branding irons and the heat distributions in the embryos are analytically modeled. Micron-scale labels on unfertilized bovine embryos are achieved.

  20. Molecular analysis of chicken embryo SPARC (osteonectin).

    PubMed

    Bassuk, J A; Iruela-Arispe, M L; Lane, T F; Benson, J M; Berg, R A; Sage, E H

    1993-11-15

    SPARC is a secreted glycoprotein that modulates cell shape and cell-matrix interactions. Levels of SPARC are increased at sites of somitogenesis, osteogenesis, and angiogenesis in the embryo and during wound repair in the adult. We have cloned and characterized SPARC from chicken embryo. A 2.2-kbp cDNA, obtained by a novel use of the polymerase chain reaction, was determined to encode a 298-residue protein that is 85% identical to human SPARC. Antigenic sites in particular appear to be highly conserved, as antibodies against C-terminal sequences of murine and bovine SPARC reacted with a 41-43 kDa protein in chicken embryo extracts. Chicken SPARC can be defined by four sequence signatures: (a) a conserved spacing of 11 cysteine residues in domain II, (b) the pentapeptide KKGHK in domain II, which is contained within a larger region of 31 identical residues, (c) a 100% conserved region of 10 residues in domain III, and (d) a C-terminal, calcium-binding EF-hand motif. SPARC mRNAs in the 10-day-old chicken embryo are represented by three sizes of 1.8, 2.2 and 3.0 kb. The relative steady-state levels for the 2.2-kb mRNA were determined as aorta > or = skeletal muscle > calvarium > vertebra > anterior limb > kidney > heart > brain > skin and lung > liver. The relative abundance of the 1.8-kb and 2.2-kb mRNAs varied among tissues and indicated that differential processing of SPARC mRNAs might occur. All three RNA species were detected by a cDNA probe for the N-terminal part of the coding region. Thus, the three mRNA species appear to arise from differential 3' splicing and/or polyadenylation. Collective evidence demonstrates that SPARC has been well-conserved during vertebrate evolution, a finding that indicates a fundamental role for this protein in development. PMID:7916692

  1. Contour extraction of Drosophila embryos.

    PubMed

    Li, Qi; Kambhamettu, Chandra

    2011-01-01

    Contour extraction of Drosophila (fruit fly) embryos is an important step to build a computational system for matching expression pattern of embryonic images to assist the discovery of the nature of genes. Automatic contour extraction of embryos is challenging due to severe image variations, including 1) the size, orientation, shape, and appearance of an embryo of interest; 2) the neighboring context of an embryo of interest (such as nontouching and touching neighboring embryos); and 3) illumination circumstance. In this paper, we propose an automatic framework for contour extraction of the embryo of interest in an embryonic image. The proposed framework contains three components. Its first component applies a mixture model of quadratic curves, with statistical features, to initialize the contour of the embryo of interest. An efficient method based on imbalanced image points is proposed to compute model parameters. The second component applies active contour model to refine embryo contours. The third component applies eigen-shape modeling to smooth jaggy contours caused by blurred embryo boundaries. We test the proposed framework on a data set of 8,000 embryonic images, and achieve promising accuracy (88 percent), that is, substantially higher than the-state-of-the-art results.

  2. Haemoproteus balearicae and other blood parasites of free-ranging Florida sandhill crane chicks

    USGS Publications Warehouse

    Dusek, R.J.; Spalding, M.G.; Forrester, Donald J.; Greiner, E.C.

    2004-01-01

    We obtained blood smears from 114 Florida sandhill crane (Grus canadensis pratensis) chicks in Osceola and Lake Counties, Florida, USA, during 1998-2000. Leucocytozoon grusi was observed in 11 (10%) chicks; Haemoproteus antigonis was observed in eight (7%) chicks; and three (3%) chicks were infected with Haemoproteus balearicae. One chick infected with H. balearicae suffered from severe anemia (packed cell volume=13%) and was later found moribund. At necropsy this bird also had severe anemia and damage to the heart possibly due to hypoxia. This is the first report of H. balearicae in free-ranging North American cranes. ?? Wildlife Disease Association 2004.

  3. Elites, Masses, and Media Blacklists: The Dixie Chicks Controversy

    ERIC Educational Resources Information Center

    Rossman, Gabriel

    2004-01-01

    Several studies have shown the influence of ownership on media content in routine contexts, but none has quantitatively tested it in the context of a crisis. Recently the country musicians the Dixie Chicks were blacklisted from the radio for criticizing the president in wartime. I use this event to test the role of media ownership in a crisis.…

  4. Brooding chicks with or without supplemental heat and light

    NASA Astrophysics Data System (ADS)

    Kese, A. G.; Donkoh, A.; Baafi, M. F.

    1984-03-01

    The need for supplemental heat in brooding chicks in a hot humid tropical area where prevalent mean environmental temperature and relative humidity are 33°C and 60%, respectively, was tested in an experiment using 320 broiler chickens. The chicks were divided into four quadruplicate lots of 20 birds each and were brooded with or without supplemental heat and light for periods varying between zero and 28 days. Each treatment group of 80 birds was subjected to one of four heat and light treatments, namely: supplementation with heat and light for the 28-day brooding period (control), supplementation with heat and light for the first 14-days only, supplementation for the last 14-days only and non-supplementation with heat and light for the entire 28-day period. Final body weight, body weight gain, feed consumption, feed conversion efficiency and mortality were not significantly (P>0.05) affected by the treatments. However, chicks brooded with supplemental heat and light for 28 days consumed significantly more water than all others. Chicks brooded without supplemental heat and light for 28 days had significantly (P<0.05) higher haemoglobin and hematocrit values than all others.

  5. Postnatal development of northern fulmar chicks, Fulmarus glacialis.

    PubMed

    Phillips, R A; Hamer, K C

    2000-01-01

    The slow growth and large fat stores characteristic of many pelagic seabird chicks were generally assumed to reflect infrequent and unpredictable food provisioning by parents. Much less attention has been focused on the importance of intrinsic physiological processes in shaping patterns of development. In this study, we examined postnatal growth and changes in water content of different organs in fulmar chicks, Fulmarus glacialis, from Fair Isle, United Kingdom. After correcting for body size, mass growth rate was as high as in inshore-feeding species, which did not support the notion of an external constraint on growth imposed by the unpredictability of pelagic prey. Pectoral muscles and plumage grew more rapidly than other tissues. Pectorals also had a high water index, probably indicating slower maturation compared with leg muscles, which need to generate heat earlier on to free adults from brooding requirements. Lean dry mass of liver, kidney, and gut decreased markedly toward fledging, presumably because of high energetic costs of maintaining large metabolic machinery in older chicks and analogous to the situation in adult waders before migration. These results suggest that the general pattern of development of fulmars may be linked to changes in resource allocation as chicks grow and possibly a compromise at the tissue level between cell division and the attainment of mature function. PMID:11073795

  6. Acute Toxicity of Ochratoxins A and B in Chicks 1

    PubMed Central

    Peckham, John C.; Doupnik, Ben; Jones, Oscar H.

    1971-01-01

    Ochratoxins A and B were given to 1-day-old Babcock B-300 cockerels to evaluate acute toxic effects. Two trials with ochratoxin A gave 7-day oral median lethal dose estimates of 116 μg (3.3 mg/kg) and 135 μg (3.9 mg/kg) per chick. Chicks given daily oral doses of 100 μg of ochratoxin A died on the second day. Single subcutaneous doses of 400 μg of ochratoxin A were also lethal. The 7-day oral median lethal dose of B was estimated at 1,890 μg (54 mg/kg) per chick. Chicks given oral doses of 100 μg of ochratoxin B daily for 10 days survived. Sublethal doses of both ochratoxins A and B resulted in growth suppression which was proportional to the amount of ochratoxin given. Visceral gout was the principal gross finding. Microscopic examinations revealed acute nephrosis, hepatic degeneration or focal necrosis, and enteritis. Suppression of hematopoiesis in the bone marrow and depletion of lymphoid elements from the spleen and bursa of Fabricius were frequently seen. Both ochratoxins appeared to have similar pathological effects. This is the first report on the toxicity of ochratoxin B. PMID:4928604

  7. Safety of West Nile Virus vaccines in sandhill crane chicks

    USGS Publications Warehouse

    Olsen, G.H.; Miller, K.J.; Docherty, D.E.; Bochsler, V.S.; Folk, Martin J.; Nesbitt, Stephen A.

    2008-01-01

    West Nile virus arrived in North America in 1999 and has spread across the continent in the ensuing years. The virus has proven deadly to a variety of native avian species including sandhill cranes (Grus canadensis). In order to provide safe and efficacious protection for captive and released populations of whooping cranes (G. americana), we have conducted a series of four research projects. The last of these was a study of the effects of two different West Nile virus vaccines on young Florida sandhill crane (G. c. pratensis) chicks and subsequent challenge with the virus. We found that vaccinating crane chicks as early as day 7 post-hatch caused no adverse reactions or noticeable morbidity. We tested both a commercial equine vaccine West Nile - Innovator (Fort Dodge Laboratories, Fort Dodge, Iowa) and a new recombinant DNA vaccine (Centers for Disease Control). We had a 33% mortality in control chicks (n =6) from West Nile virus infection, versus 0% mortality in two groups of vaccinated chicks (n = 12), indicating the two vaccines tested were not only safe but effective in preventing West Nile virus.

  8. Lectin histochemistry of microvascular endothelium in chick and quail musculature.

    PubMed

    Nanka, O; Peumans, W J; Van Damme, E J; Pfüller, U; Valásek, P; Halata, Z; Schumacher, U; Grim, M

    2001-11-01

    The lectin binding pattern of muscular microvessels in chick, quail and chick/quail chimeras was analysed. Paraffin wax sections of muscles from embryonic and adult animals were used. The biotin-labelled lectins were detected by avidin-alkaline phosphatase complex. The following lectins bound to muscular microvessels including arterioles, capillaries and venules of both species: SNA-I (Sambucus nigra agglutinin), MAA (Maackia amurensis agglutinin), AIA (Artocarpus integrifolia agglutinin), VAA-I, VAA-II and VAA-III (Viscum album agglutinin I-III), WGA (wheat germ agglutinin), LEA (Lycopersicon esculentum agglutinin). Endomysium and basement membranes of muscle fibres were also stained to a variable extent and intensity. Only SNA-I stained almost exclusively the endothelium of blood vessels. WFA (Wisteria floribunda agglutinin) bound to the quail endothelium only. MPA (Maclura pomifera agglutinin) marked vessels in adult muscles of chick and quail, but embryonic vessels were stained in quail only. Our results show that lectin histochemistry is a useful tool for visualisation of microvasculature in avian species. In particular, WFA and MPA can be used to determine the origin of endothelia in chick/quail chimeras.

  9. Auditory and vestibular pathology of seizure-prone chicks.

    PubMed

    Beck, M M; Kuenzel, W J; Switzer, R C

    1983-01-31

    The mutant sex-linked lethal recessive px (paroxysmal) gene, expressed in White Leghorn chicks (Gallus domesticus) causes seizures beginning on approximately day 8 post-hatching. Seizures are spontaneous and inducible by auditory but not by photic stimulation. Prior to seizure onset px chicks are indistinguishable from non-px siblings. With seizure onset is a decrease in food intake which causes deterioration and death by 4-10 weeks of age. In a preliminary histological study conducted on 22-day-old seizure-prone chicks, brains were perfused and sections treated according to a modified cupric-silver staining technique. Nuclei and fiber tracts of px auditory and vestibular systems were extensively degenerated; control brains showed essentially no degeneration. A second experiment was conducted with preseizure chicks to determine whether and to what extent degeneration occurs prior to seizure onset. Deep nuclei of px cerebellum appeared to be the first seriously affected (5 days of age). Extent of degeneration progressed steadily over time through 20 days of age, by which time all components of the two sensory systems were maximally affected. Ambient noise did not affect onset or extent of degeneration, nor did it affect onset of seizures. PMID:6824948

  10. Intuitive physical reasoning about occluded objects by inexperienced chicks

    PubMed Central

    Chiandetti, Cinzia; Vallortigara, Giorgio

    2011-01-01

    Questions concerning the role of nature and nurture in higher cognition appear to be intractable if one restricts one's attention to development in humans. However, in other domains, such as sensory development, much information has been gained from controlled rearing studies with animals. Here, we used a similar experimental strategy to investigate intuitive reasoning about occluded objects. Newborn domestic chicks (Gallus gallus) were reared singly with a small object that became their social partner. They were then accustomed to rejoin such an imprinting object when it was made to move and disappear behind either one of two identical opaque screens. After disappearance of the imprinting object, chicks were faced with two screens of different slants, or of different height or different width, which may or may not have been compatible with the presence of the imprinting object hidden beneath/behind them. Chicks consistently chose the screen of slant/height/width compatible with the presence of the object beneath/behind it. Preventing chicks from touching and pecking at the imprinting object before testing did not affect the results, suggesting that intuitive reasoning about physical objects is largely independent of specific experience of interaction with objects and of objects' occluding events. PMID:21270036

  11. Developmental basis for hind-limb loss in dolphins and origin of the cetacean bodyplan

    PubMed Central

    Thewissen, J. G. M.; Cohn, M. J.; Stevens, L. S.; Bajpai, S.; Heyning, J.; Horton, W. E.

    2006-01-01

    Among mammals, modern cetaceans (whales, dolphins, and porpoises) are unusual in the absence of hind limbs. However, cetacean embryos do initiate hind-limb bud development. In dolphins, the bud arrests and degenerates around the fifth gestational week. Initial limb outgrowth in amniotes is maintained by two signaling centers, the apical ectodermal ridge (AER) and the zone of polarizing activity (ZPA). Our data indicate that the cetacean hind-limb bud forms an AER and that this structure expresses Fgf8 initially, but that neither the AER nor Fgf8 expression is maintained. Moreover, Sonic hedgehog (Shh), which mediates the signaling activity of the ZPA, is absent from the dolphin hind-limb bud. We find that failure to establish a ZPA is associated with the absence of Hand2, an upstream regulator of Shh. Interpreting our results in the context of both the cetacean fossil record and the known functions of Shh suggests that reduction of Shh expression may have occurred ≈41 million years ago and led to the loss of distal limb elements. The total loss of Shh expression may account for the further loss of hind-limb elements that occurred near the origin of the modern suborders of cetaceans ≈34 million years ago. Integration of paleontological and developmental data suggests that hind-limb size was reduced by gradually operating microevolutionary changes. Long after locomotor function was totally lost, modulation of developmental control genes eliminated most of the hind-limb skeleton. Hence, macroevolutionary changes in gene expression did not drive the initial reduction in hind-limb size. PMID:16717186

  12. Survival costs of chick rearing in black-legged kittiwakes

    USGS Publications Warehouse

    Golet, G.H.; Irons, D.B.; Estes, J.A.

    1998-01-01

    1. We tested for costs of chick rearing in the black-legged kittiwake Rissa tridactyla (Linnaeus) by removing entire clutches from 149 of 405 randomly selected nests, in which one or both mates was colour-banded. After the manipulation, we monitored adult nest attendance and body condition at unmanipulated and manipulated nests, and measured the survival and fecundity of these adults the following year. 2. Late in the chick-rearing period, adults from unmanipulated nests (i.e. with chicks) went on significantly longer foraging trips, and were significantly lighter for their size, than adults from manipulated nests (i.e. without chicks). 3. Adults from unmanipulated nests also survived to the following nesting season at a significantly lower rate than those from the manipulated nests (0.898 vs. 0.953), suggesting that attempting to raise chicks can reduce life expectancy by 55%. 4. There was a tendency for adults from nests that were unmanipulated in year one to have lower reproductive success in year two, primarily because of reduced fledging success, and a higher incidence of non-breeding. 5. These findings suggest that mass loss in kittiwakes during chick rearing may not be adaptive. Raising chicks can lead to reproductive costs, and the causal mechanism appears to be a reduction in body condition. 6. We compare our results with previous brood (or clutch) size manipulation experiments that have measured adult body condition, survival and/or future fecundity. Although the empirical evidence suggests that long-lived species are more likely to experience survival costs than short-lived species, we believe the opposite may be true. We suggest that shifting the experimental protocol of cost of reproduction studies from brood enlargements (an approach taken in most prior studies) to brood reductions will provide more accurate quantifications of naturally occurring costs. 7. The cost of reproduction is one mechanism proposed to explain the reduced survival rates

  13. Pigmented epithelium induces complete retinal reconstitution from dispersed embryonic chick retinae in reaggregation culture.

    PubMed Central

    Rothermel, A; Willbold, E; Degrip, W J; Layer, P G

    1997-01-01

    Reaggregation of dispersed retinal cells of the chick embryo leads to histotypic retinospheroids in which the laminar organization remains incomplete: photoreceptors form rosettes which are surrounded by constituents of the other retinal layers. Here, for the first time, a complete arrangement of layers is achieved in cellular spheres (stratoids), provided that fully dispersed retinal cells are younger than embryonic day E6, and are reaggregated in the presence of a monolayer of retinal pigmented epithelium (RPE). A remarkable mechanism of stratoid formation from 1 to 15 days in vitro is revealed by the establishment of a radial Müller glia scaffold and of photoreceptors. During the first two days of reaggregation on RPE, rosettes are still observed. At this stage immunostaining with vimentin and F11 antibodies for radial Müller glia reveal a disorganized pattern. Subsequently, radial glia processes organize into long parallel fibre bundles which are arranged like spokes to stabilize the surface and centre of the stratoid. The opsin-specific antibody CERN 901 detects photoreceptors as they gradually build up an outer nuclear layer at the surface. These findings assign to the RPE a decisive role for the genesis and regeneration of a vertebrate retina. PMID:9332014

  14. Chick Chorioallantoic Membrane Assay: A 3D Animal Model for Study of Human Nasopharyngeal Carcinoma

    PubMed Central

    Ming, Huixin; Zhang, Jinyan; Huang, Guangwu; Zhang, Zhe; Li, Ping

    2015-01-01

    Nasopharyngeal carcinoma (NPC) is a highly invasive and metastatic head and neck cancer. However, mechanistic study of the invasion and metastasis of NPC has been hampered by the lack of proper in vivo models. We established an in vivo chick embryo chorioallantoic membrane (CAM) model to study NPC tumor biology. We found 100% micro-tumor formation 3 days after inoculation with NPC cell lines (4/4) or primary tumor biopsy tissue (35/35). The transplanted NPC micro-tumors grew on CAMs with extracellular matrix interaction and induced angiogenesis. In addition, the CAM model could be used to study the growth of transplanted NPC tumors and also several important steps of metastasis, including tumor invasion by detecting the extent of basement membrane penetration, tumor angiogenesis by analyzing the area of neo-vessels, and tumor metastasis by quantifying tumor cells in distant organs. We established and described a feasible, easy-to-manipulate and reliable CAM model for in vivo study of NPC tumor biology. This model closely simulates the clinical features of NPC growth, progression and metastasis and could help elucidate the biological mechanisms of the growth pattern and invasion of NPC cells and in quantitative assessment of angiogenesis and cell intravasation. PMID:26107941

  15. The chick retinal pigment epithelium grown on permeable support demonstrates functional polarity

    SciTech Connect

    Koh, S.W.M )

    1989-04-01

    The retinal pigment epithelium (RPE) from the chick embryo was cultured permeable support. Using confluent cultures and analysis of the incubation medium, the present study demonstrates that RPE cells cultured on permeable membrane retain functional polarity, a characteristic of the RPE in vivo. The degree of intercellular permeability in the confluent RPE cultures was estimated by following ({sup 3}H)inulin movement from the apical side to the basal side of the cultures. Twenty-four hours after exposure of the apical side of the culture to ({sup 3}H)inulin, the {sup 3}H concentration in the apical medium remained at 3.4 to 4.4 times of that in the basal medium. When cultures are given 26 hours of ({sup 35}S)methionine, more than 20 bands with molecular weights ranging from 20,000 to > 250,000 Da can be detected in the medium as assessed by autoradiography of SDS-polyacrylamide gels. Electron microscopy of the confluent RPE cultures shows morphological polarization of the cells. The intercellular spaces appear to be closed at the apical side of the cells by junctional complexes consisting of tight junctions, zonular adherens junctions, and gap junctions.

  16. 4D subject-specific inverse modeling of the chick embryonic heart outflow tract hemodynamics.

    PubMed

    Goenezen, Sevan; Chivukula, Venkat Keshav; Midgett, Madeline; Phan, Ly; Rugonyi, Sandra

    2016-06-01

    Blood flow plays a critical role in regulating embryonic cardiac growth and development, with altered flow leading to congenital heart disease. Progress in the field, however, is hindered by a lack of quantification of hemodynamic conditions in the developing heart. In this study, we present a methodology to quantify blood flow dynamics in the embryonic heart using subject-specific computational fluid dynamics (CFD) models. While the methodology is general, we focused on a model of the chick embryonic heart outflow tract (OFT), which distally connects the heart to the arterial system, and is the region of origin of many congenital cardiac defects. Using structural and Doppler velocity data collected from optical coherence tomography, we generated 4D ([Formula: see text]) embryo-specific CFD models of the heart OFT. To replicate the blood flow dynamics over time during the cardiac cycle, we developed an iterative inverse-method optimization algorithm, which determines the CFD model boundary conditions such that differences between computed velocities and measured velocities at one point within the OFT lumen are minimized. Results from our developed CFD model agree with previously measured hemodynamics in the OFT. Further, computed velocities and measured velocities differ by [Formula: see text]15 % at locations that were not used in the optimization, validating the model. The presented methodology can be used in quantifications of embryonic cardiac hemodynamics under normal and altered blood flow conditions, enabling an in-depth quantitative study of how blood flow influences cardiac development.

  17. Raman spectral study of anti-angiogenic drugs on the role of chick vascular

    NASA Astrophysics Data System (ADS)

    Huang, Ruixiang; Chen, Rong; Chen, Qisong; Lin, Juqiang; Pan, Jianji; Lin, Shaojun; Li, Chao; Li, Yongzeng; Feng, Shangyuan

    2009-08-01

    Inhibit angiogenesis is one of the important tumor therapy. If the mechanism of vascular changes can be detected at molecular level, it will have therapeutic significance. Raman spectroscopy, which can be applied to the structural analysis of solid, liquid or solution of biological molecules, is a non-destructive spectral technology holding very rich information. Basing on Confocal Raman Microscope, a unique system is developed for obtaining the different Raman spectra of the chick embryo vascular with the anti-angiogenic drugs - thalidomide and without. In the study, the location and shape of the average Raman spectra of vessels in drug 5h were very similar to the ones without medicine, and the intensity of some characteristic peaks changed, such as 1441cm-1,1527cm-1 and 1657cm-1 showing markedly increasing, while the 971cm-1 and 1081cm-1 decreasing. This change was due to anti- angiogenic drugs that caused the nucleic acid, protein, phospholipids, and other important biological molecules of the vessels on the structure or content tovary. PCA was used to distinguish between the two kinds of vascular with the result that they were accurately partitioned.The study indicated that Raman spectroscopy could be an effective tool for detection of the mechanism of vascular changes.

  18. RNA-Seq Analysis of Differential Gene Expression in Electroporated Chick Embryonic Spinal Cord

    PubMed Central

    Vieceli, Felipe M.; Yan, C.Y. Irene

    2014-01-01

    In ovo electroporation of the chick neural tube is a fast and inexpensive method for identification of gene function during neural development. Genome wide analysis of differentially expressed transcripts after such an experimental manipulation has the potential to uncover an almost complete picture of the downstream effects caused by the transfected construct. This work describes a simple method for comparing transcriptomes from samples of transfected embryonic spinal cords comprising all steps between electroporation and identification of differentially expressed transcripts. The first stage consists of guidelines for electroporation and instructions for dissection of transfected spinal cord halves from HH23 embryos in ribonuclease-free environment and extraction of high-quality RNA samples suitable for transcriptome sequencing. The next stage is that of bioinformatic analysis with general guidelines for filtering and comparison of RNA-Seq datasets in the Galaxy public server, which eliminates the need of a local computational structure for small to medium scale experiments. The representative results show that the dissection methods generate high quality RNA samples and that the transcriptomes obtained from two control samples are essentially the same, an important requirement for detection of differential expression genes in experimental samples. Furthermore, one example is provided where experimental overexpression of a DNA construct can be visually verified after comparison with control samples. The application of this method may be a powerful tool to facilitate new discoveries on the function of neural factors involved in spinal cord early development. PMID:25406837

  19. Automated Segmentation and Object Classification of CT Images: Application to In Vivo Molecular Imaging of Avian Embryos

    PubMed Central

    Schmidt, Jana; Zimmermann, Johannes; Saluz, Hans Peter

    2013-01-01

    Background. Although chick embryogenesis has been studied extensively, there has been growing interest in the investigation of skeletogenesis. In addition to improved poultry health and minimized economic loss, a greater understanding of skeletal abnormalities can also have implications for human medicine. True in vivo studies require noninvasive imaging techniques such as high-resolution microCT. However, the manual analysis of acquired images is both time consuming and subjective. Methods. We have developed a system for automated image segmentation that entails object-based image analysis followed by the classification of the extracted image objects. For image segmentation, a rule set was developed using Definiens image analysis software. The classification engine was implemented using the WEKA machine learning tool. Results. Our system reduces analysis time and observer bias while maintaining high accuracy. Applying the system to the quantification of long bone growth has allowed us to present the first true in ovo data for bone length growth recorded in the same chick embryos. Conclusions. The procedures developed represent an innovative approach for the automated segmentation, classification, quantification, and visualization of microCT images. MicroCT offers the possibility of performing longitudinal studies and thereby provides unique insights into the morpho- and embryogenesis of live chick embryos. PMID:23997760

  20. Logic in an asymmetrical (social) brain: Transitive inference in the young domestic chick.

    PubMed

    Daisley, Jonathan Niall; Vallortigara, Giorgio; Regolin, Lucia

    2010-01-01

    The ability of animals to perform transitive inference is associated with social group formation and dominance hierarchies. Brain lateralization is also linked to the selective pressures associated with social life. We investigated whether transitive inference is better performed by lateralized than non-lateralized brains. In the domestic chick (Gallus gallus) exposure of eggs to light before hatching leads to the development of lateralization of some visual functions. Thus, it is possible to obtain chicks with strong (light-incubated, Li-chicks) or weak (dark-incubated, Di-chicks) lateralization. Di- and Li-chicks were trained to discriminate stimulus pairs, in order to build a hierarchy (A > B > C > D > E). Chicks were subsequently tested on stimulus pairs never seen together before (AE and BD). Li-chicks performed the discrimination BD better than did Di-chicks, suggesting that exposure to light in the egg leads to an increased ability to carry out representational learning. Moreover, lateralized chicks using their left eye only (right hemisphere) during test showed a better performance than did right eye only (left hemisphere) chicks on the BD task. Females also tended to perform better than males. Results demonstrate that chicks with lateralized brain hemispheres show greater inference, and this is under right hemisphere control: the brain hemisphere that is dominant in social interactions.

  1. Analysis of nephric duct specification in the avian embryo

    PubMed Central

    Attia, Lital; Yelin, Ronit; Schultheiss, Thomas M.

    2012-01-01

    Vertebrate kidney tissue exhibits variable morphology that in general increases in complexity when moving from anterior to posterior along the body axis. The nephric duct, a simple unbranched epithelial tube, is derived in the avian embryo from a rudiment located in the anterior intermediate mesoderm (IM) adjacent to somites 8 to 10. Using quail-chick chimeric embryos, the current study finds that competence to form nephric duct is fixed when IM precursor cells are still located in the primitive streak, significantly before the onset of duct differentiation. In the primitive streak, expression of the gene HoxB4 is associated with prospective duct IM, whereas expression of the more posterior Hox gene HoxA6 is associated with more posterior, non-duct-forming IM. Misexpression of HoxA6, but not of HoxB4, in prospective duct-forming regions of the IM resulted in repression of duct formation, suggesting a mechanism for the restriction of duct formation to the anterior-most IM. The results are discussed with respect to their implications for anterior-posterior patterning of kidney tissue and of mesoderm in general, and for the loss of duct-forming ability in more posterior regions of the IM that has occurred during vertebrate evolution. PMID:23034630

  2. Interactions among arsenic, zinc, and taurine in chicks

    SciTech Connect

    Uthus, E.O.; Nielsen, F.H.

    1986-03-01

    A 2 x 2 x 2 factorially arranged experiment was done using day-old cockerel chicks to ascertain whether Zn and taurine (Tau), through changing methionine (Met) or sulfate metabolism, affect signs of As deprivation. The dietary variables were supplements of As, 0 or 2 ..mu..g/g; Zn, 10 or 40 ..mu..g/g; and Tau, 0 or 0.84%. The basal diet contained (per g): 15 ng As, 7 ..mu..g Zn, and 5.65 mg Met. For comparison purposes two additional groups of chicks were fed diets supplemented with 0 or 2 ..mu..g As, 40 ..mu..G Zn, 0 Tau, and 0.5 Met. After 26 days, Tau supplementation alleviated many perturbations caused by an apparent methionine deficiency. For example, final body wt was increased from 596 g to 741 g. However, Tau was much less effective than Met in inhibiting the elevation in plasma Mo caused by Met lack. An interaction between Tau and Zn affected several indices including liver Zn concentration. Tau decreased the liver Zn concentration when dietary Zn was 40 ..mu..g/g. An interaction between Tau and As affected plasma urea. Supplemental As elevated urea in chicks fed 0 Tau, but depressed urea in chicks fed 0.84% Tau. Kidney arginase tended to follow a similar trend. The findings show that Tau can fulfill some of the Met requirements of chicks and that Tau interacts with Zn and As. Some findings also support the hypothesis that As has a physiological role that affects arginine and Met metabolism.

  3. Development of Experimental Myopia in Chicks in a Natural Environment

    PubMed Central

    Stone, Richard A.; Cohen, Yuval; McGlinn, Alice M.; Davison, Sherrill; Casavant, Susan; Shaffer, James; Khurana, Tejvir S.; Pardue, Machelle T.; Iuvone, P. Michael

    2016-01-01

    Purpose The hypothesis that outdoor exposure might protect against myopia has generated much interest, although available data find only modest clinical efficacy. We tested the effect of outdoor rearing on form-deprivation myopia in chicks, a myopia model markedly inhibited by high-intensity indoor laboratory lighting. Methods Unilaterally goggled cohorts of White Leghorn chicks were maintained in a species-appropriate, outdoor rural setting during daylight hours to the extent permitted by weather. Control chicks were reared indoors with incandescent lighting. Besides ocular refraction and ultrasound, we determined dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) content in retina and vitreous and measured mRNA expression levels of selected clock and circadian rhythm-related genes in the retina/RPE. Results Myopia developed in the goggled eyes of all cohorts. Whereas outdoor rearing lessened myopia by 44% at 4 days, a protective effect was no longer evident at 11 days. Outdoor rearing had no consistent effect on retinal or vitreous content of dopamine or DOPAC. Conforming to prior data on form-deprivation myopia, retina and vitreous levels of DOPAC were reduced in goggled eyes. Compared with contralateral eyes, the retinal expression of clock and circadian rhythm-related genes was modestly altered in myopic eyes of chicks reared indoors or outdoors. Conclusions Outdoor rearing of chicks induces only a partial decrease of goggle-induced myopia that is not maintained, without evidence that retinal dopamine metabolism accounts for the partial myopia inhibition under these outdoor conditions. Although modest, alterations in retinal gene expression suggest that studying circadian signals might be informative for understanding refractive mechanisms. PMID:27618415

  4. California gull chicks raised near colony edges have elevated stress levels

    USGS Publications Warehouse

    Herring, Garth; Ackerman, Joshua T.

    2011-01-01

    Coloniality in nesting birds represents an important life history strategy for maximizing reproductive success. Birds nesting near the edge of colonies tend to have lower reproductive success than individuals nesting near colony centers, and offspring of edge-nesting parents may be impaired relative to those of central-nesting parents. We used fecal corticosterone metabolites in California gull chicks (Larus californicus) to examine whether colony size or location within the colony influenced a chick's physiological condition. We found that chicks being raised near colony edges had higher fecal corticosterone metabolite concentrations than chicks raised near colony centers, but that colony size (ranging from 150 to 11,554 nests) had no influence on fecal corticosterone levels. Fecal corticosterone metabolite concentrations also increased with chick age. Our results suggest that similarly aged California gull chicks raised near colony edges may be more physiologically stressed, as indicated by corticosterone metabolites, than chicks raised near colony centers.

  5. Feeding behavior and growth of broiler chicks fed larvae of the darkling beetle, Alphitobius diaperinus.

    PubMed

    Despins, J L; Axtell, R C

    1995-02-01

    Experiments were conducted to determine the effects of feeding larvae of the darkling beetle (lesser mealworm), Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae) to broiler chicks on chick growth. Chicks readily fed on the larvae and exhibited reduced growth in the absence of other feed. Chicks 3 to 8 d old restricted to a diet of only larvae consumed 1,552 +/- 172 (mean +/- SD) larvae per chick per day and their body weights were significantly less (mean = 84 g) at the end of the 6 d than for chicks on starter feed during the same time. After return to starter feed for 8 d after feeding on larvae for 6 d, the chicks did not compensate for the reduced weight and their body weights were significantly less (mean = 170 g) than for chicks on starter feed for the 14 d. Chicks from age 2 through 9 d were given a choice between broiler starter feed and darkling beetle larvae. The numbers (mean +/- SD) of larvae consumed per chick per day were: 389 +/- 18, 631 +/- 14, 496 +/- 20, and 287 +/- 33, for Days 2 to 3, 4 to 5, 6 to 7, and 8 to 9, respectively. The body weight of chicks feeding on starter feed and larvae was significantly greater than the weight of chicks consuming feed only. In the presence of larvae, the mean feed consumption per chick was less than for chicks provided with only starter feed. The beetle larvae were 68% crude protein and 21% fat (DM basis) and had higher amounts of 18 amino acids than the starter feed.

  6. Management of Major Limb Injuries

    PubMed Central

    Langer, Vijay

    2014-01-01

    Management of major limb injuries is a daunting challenge, especially as many of these patients have severe associated injuries. In trying to save life, often the limb is sacrificed. The existing guidelines on managing such trauma are often confusing. There is scope to lay down such protocols along with the need for urgent transfer of such patients to a multispecialty center equipped to salvage life and limb for maximizing outcome. This review article comprehensively deals with the issue of managing such major injuries. PMID:24511296

  7. Simulation of Upper Limb Movements

    NASA Astrophysics Data System (ADS)

    Uherčík, Filip; Hučko, Branislav

    2011-12-01

    The paper deals with controlling an upper limb prosthesis based on the measurement of myoelectric signals (MES) while drinking. MES signals have been measured on healthy limbs to obtain the same response for the prosthesis. To simulate the drinking motion of a healthy upper limb, the program ADAMS was used, with all degrees of freedom and a hand after trans-radial amputation with an existing hand prosthesis. Modification of the simulation has the exact same logic of control, where the muscle does not have to be strenuous all the time, but it is the impulse of the muscle which drives the motor even though the impulse disappears and passed away.

  8. Characterization of the finch embryo supports evolutionary conservation of the naive stage of development in amniotes

    PubMed Central

    Mak, Siu-Shan; Alev, Cantas; Nagai, Hiroki; Wrabel, Anna; Matsuoka, Yoko; Honda, Akira; Sheng, Guojun; Ladher, Raj K

    2015-01-01

    Innate pluripotency of mouse embryos transits from naive to primed state as the inner cell mass differentiates into epiblast. In vitro, their counterparts are embryonic (ESCs) and epiblast stem cells (EpiSCs), respectively. Activation of the FGF signaling cascade results in mouse ESCs differentiating into mEpiSCs, indicative of its requirement in the shift between these states. However, only mouse ESCs correspond to the naive state; ESCs from other mammals and from chick show primed state characteristics. Thus, the significance of the naive state is unclear. In this study, we use zebra finch as a model for comparative ESC studies. The finch blastoderm has mESC-like properties, while chick blastoderm exhibits EpiSC features. In the absence of FGF signaling, finch cells retained expression of pluripotent markers, which were lost in cells from chick or aged finch epiblasts. Our data suggest that the naive state of pluripotency is evolutionarily conserved among amniotes. DOI: http://dx.doi.org/10.7554/eLife.07178.001 PMID:26359635

  9. Metabolomic assessment of embryo viability.

    PubMed

    Uyar, Asli; Seli, Emre

    2014-03-01

    Preimplantation embryo metabolism demonstrates distinctive characteristics associated with the developmental potential of embryos. On this basis, metabolite content of culture media was hypothesized to reflect the implantation potential of individual embryos. This hypothesis was tested in consecutive studies reporting a significant association between culture media metabolites and embryo development or clinical pregnancy. The need for a noninvasive, reliable, and rapid embryo assessment strategy promoted metabolomics studies in vitro fertilization (IVF) in an effort to increase success rates of single embryo transfers. With the advance of analytical techniques and bioinformatics, commercial instruments were developed to predict embryo viability using spectroscopic analysis of surplus culture media. However, despite the initial promising results from proof-of-principal studies, recent randomized controlled trials using commercial instruments failed to show a consistent benefit in improving pregnancy rates when metabolomics is used as an adjunct to morphology. At present, the application of metabolomics technology in clinical IVF laboratory requires the elimination of factors underlying inconsistent findings, when possible, and development of reliable predictive models accounting for all possible sources of bias throughout the embryo selection process. PMID:24515909

  10. [Embryology, anomalies, dystrophy and pathology of the lower limbs arteries (author's transl)].

    PubMed

    Kim, M; Dupuy, J P; Dany, F

    1981-01-01

    The development in the embryo of the lower limbs arteries is made by means of the retrogression of the ischiatic artery, which is initially preponderant, and of the persistence in the popliteal pit of an anastomosis between the original ischiatic axis and the final femoral axis. The tibial arteries originate from one or the other of these axes. The attention is turned to the areas rendered fragile by the complexity of their forming and likely to provoke some topographic anomaly or some dystrophic disease: persistence of the ischiatic artery, trapped popliteal artery, gelatinous dystrophy, Leriche-Fontaine aneurysmal dystrophy, anterior tibial hypoplasia. The repetition of such problems which are non-existent at the upper limbs and are localized to the same arterial segments, especially to the popliteal artery, puts stress upon an eventual dysplasic pathogenesis originating from the embryo. PMID:7288326

  11. Prevalence and Characteristics of Phantom Limb Pain and Residual Limb Pain in the Long Term after Upper Limb Amputation

    ERIC Educational Resources Information Center

    Desmond, Deirdre M.; MacLachlan, Malcolm

    2010-01-01

    This study aims to describe the prevalence and characteristics of phantom limb pain and residual limb pain after upper limb amputation. One-hundred and forty-one participants (139 males; mean age 74.8 years; mean time since amputation 50.1 years) completed a self-report questionnaire assessing residual and phantom limb pain experience. Prevalence…

  12. Differentiation of cartilaginous anlagen in entire embryonic mouse limbs cultured in a rotating bioreactor

    NASA Astrophysics Data System (ADS)

    Montufar-Solis, D.; Oakley, C. R.; Jefferson, Y.; Duke, P. J.

    2003-10-01

    Mechanisms involved in development of the embryonic limb have remained the same throughout eons of genetic and environmental evolution under Earth gravity (lg). During the spaceflight era it has been of interest to explore the ancient theory that form of the skeleton develops in response to gravity, and that changes in gravitational forces can change the developmental pattern of the limb. This has been shown in vivo and in vitro, allowing the hypergravity of centrifugation and microgravity of space to be used as tools to increase our knowledge of limb development. In recapitulations of spaceflight experiments, premetatarsals were cultured in suspension in a bioreactor, and found to be shorter and less differentiated than those cultured in standard culture dishes. This study only measured length of the metatarsals, and did not account for possible changes due to the skeletal elements having a more in vivo 3D shape while in suspension vs. flattened tissues compressed by their own weight. A culture system with an outcome closer to in vivo and that supports growth of younger limb buds than traditional systems will allow studies of early Hox gene expression, and contribute to the understanding of very early stages of development. The purpose of the current experiment was to determine if entire limb buds could be cultured in the bioreactor, and to compare the growth and differentiation with that of culturing in a culture dish system. Fore and hind limbs from E11-E13 ICR mouse embryos were cultured for six days, either in the bioreactor or in center-well organ culture dishes, fixed, and embedded for histology. E13 specimens grown in culture dishes were flat, while bioreactor culture specimens had a more in vivo-like 3D limb shape. Sections showed excellent cartilage differentiation in both culture systems, with more cell maturation, and hypertrophy in the specimens cultured in the bioreactor. Younger limb buds fused together during culture, so an additional set of El 1

  13. Deciphering axonal pathways of genetically defined groups of neurons in the chick neural tube utilizing in ovo electroporation.

    PubMed

    Avraham, Oshri; Zisman, Sophie; Hadas, Yoav; Vald, Lilach; Klar, Avihu

    2010-05-02

    Employment of enhancer elements to drive expression of reporter genes in neurons is a widely used paradigm for tracking axonal projection. For tracking axonal projection of spinal interneurons in vertebrates, germ line-targeted reporter genes yield bilaterally symmetric labeling. Therefore, it is hard to distinguish between the ipsi- and contra-laterally projecting axons. Unilateral electroporation into the chick neural tube provides a useful means to restrict expression of a reporter gene to one side of the central nervous system, and to follow axonal projection on both sides. This video demonstrates first how to handle the eggs prior to injection. At HH stage 18-20, DNA is injected into the sacral level of the neural tube, then tungsten electrodes are placed parallel to the embryo and short electrical pulses are administered with a pulse generator. The egg is sealed with tape and placed back into an incubator for further development. Three days later (E6) the spinal cord is removed as an open book preparation from embryo, fixed, and processed for whole mount antibody staining. The stained spinal cord is mounted on slide and visualized using confocal microscopy.

  14. Intra- and interspecific embryo transfer.

    PubMed

    Kraemer, D C

    1983-11-01

    The procedures that are collectively referred to as embryo transfer (ET) have many uses. They were first used as research tools to study fetal-maternal physiology. Since the first successful mammalian embryo transfer in 1890, ET has been utilized for enhancement of genetic selection; diagnosis and treatment of infertility; control of infectious disease transmission; screening for genetic defects; propagation of rare and endangered species; and the study of developmental biology. Most of the embryo transfers have been intraspecific. A listing of the species includes rabbit, rat, sheep, mouse, goat, cattle, pig, hamster, ferret, mink, horse, baboon, cat, dog, water buffalo. In two species, rhesus monkey and humans, the successful embryo transfers have been limited to within-animal, homologous replacement of the embryos. There have been a few successful interspecific embryo transfers. The most common were between Bos taurus and B. indicus cattle. Other interspecific transfers involved Bos gaurus and B. taurus, cattle; Ovis musimon and O. aries, sheep; Equus asinus and E. caballus, horses. There are several examples of intergeneric embryo transfers in which embryos implanted but did not develop to term: sheep and goat, mouse and rat. The factors that determine the degree of compatibility between embryos and uteri of various species and genera are not clearly understood. The ability to hybridize successfully is probably a dependable indication of compatibility for embryo transfer. The limits of tolerance for differences between the donor and recipient in such factors as placental structure and gestation length have not been defined, but the recently developed technique of inner cell mass transfer will be very useful in such studies.

  15. Ambient illuminance, retinal dopamine release and refractive development in chicks.

    PubMed

    Cohen, Yuval; Peleg, Edna; Belkin, Michael; Polat, Uri; Solomon, Arieh S

    2012-10-01

    Form deprivation and low illuminance of ambient light are known to induce myopia in chicks. Low concentrations of retinal dopamine, a light-driven neurohormone, was previously shown to be associated with form deprivation myopia. In the present study we examined the dependence of retinal dopamine release in chicks on illuminance during light-dark cycles and in continuous light, and the role of retinal dopamine release in illuminance dependent refractive development. Newly hatched chicks (n = 166) were divided into two experimental groups, a dopamine (n = 88) and a refraction group (n = 78). Both groups were further divided into six illumination groups for exposure of chicks to illuminances of 50, 500 or 10,000 lux of incandescent illumination (referred to throughout as low, medium, and high illuminance, respectively), either under a light-dark cycle with lights on between 7 AM and 7 PM or under continuous illumination. For the dopamine experiment, chicks were euthanized and vitreous was extracted on day 14 post-hatching at 7, 8 AM and 1 PM. Vitreal dihydroxyphenylacetic acid (DOPAC) and dopamine concentrations were quantified by high-performance liquid chromatography coupled to electrochemical detection. For the refraction experiment, chicks underwent refraction, keratometry and A-scan ultrasonography on days 30, 60 and 90 post-hatching, and each of those measurements was correlated with vitreal DOPAC concentration measured at 1 PM (representing the index of retinal dopamine release). The results showed that under light-dark cycles, vitreal DOPAC concentration was strongly correlated with log illuminance, and was significantly correlated with the developing refraction, corneal radius of curvature, and axial length values. On day 90, low vitreal DOPAC concentrations were associated with myopia (-2.41 ± 1.23 D), flat cornea, deep anterior and vitreous chambers, and thin lens. Under continuous light, vitreal DOPAC concentrations measured at 1 PM in the low, medium

  16. Pediatric limb differences and amputations.

    PubMed

    Le, Joan T; Scott-Wyard, Phoebe R

    2015-02-01

    Congenital limb differences are uncommon birth defects that may go undetected even with prenatal screening ultrasound scans and often go undetected until birth. For children with congenital limb differences, a diagnostic evaluation should be done to rule out syndromes involving other organ systems or known associations. The most common etiology of acquired amputation is trauma. Postamputation complications include pain and terminal bony overgrowth. A multidisciplinary approach to management with the child and family can lead to a successful, functional, and fulfilling life.

  17. Ethical issues in limb transplants.

    PubMed

    Dickenson, D; Widdershoven, G

    2001-04-01

    On one view, limb transplants cross technological frontiers but not ethical ones; the only issues to be resolved concern professional competence, under the assumption of patient autonomy. Given that the benefits of limb transplant do not outweigh the risks, however, the autonomy and rationality of the patient are not necessarily self-evident. In addition to questions of resource allocation and informed consent, limb, and particularly hand, allograft also raises important issues of personal identity and bodily integrity. We present two linked schemas for exploring ethical issues in limb transplants. The first, relying on conventional concepts in biomedical ethics, asks whether the procedure is research or therapy, whether the costs outweigh the benefits, and whether it should be up to the patient to decide. The second introduces more speculative and theoretically challenging questions, including bodily integrity, the argument from unnaturalness, and the function of the hand in expressing personal identity and intimacy. We conclude that limb transplants are not ruled out a priori, unlike some procedures that are prima facie wrong to perform, such as amputation of healthy limbs to relieve body dysmorphic disorders. However, their legitimacy is not proven by appeals to the interests of scientific research, cost-benefit, or patient autonomy.

  18. Proximodistal patterning during limb regeneration.

    PubMed

    Echeverri, Karen; Tanaka, Elly M

    2005-03-15

    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 regeneration of the entire limb, while amputation at the wrist produces a hand. Limb regeneration occurs through the formation of a local proliferative zone called the blastema. Here, we examine how proximodistal identity is established in the blastema. Using cell marking and transplantation experiments, we show that distal identities have already been established in the earliest stages of blastemas examined. Transplantation of cells into new environments is not sufficient to respecify cell identity. However, overexpression of the CD59, a cell surface molecule previously implicated in proximodistal identity during limb regeneration, causes distal blastema cells to translocate to a more proximal location and causes defects in the patterning of the distal elements of the regenerate. We suggest a model for the limb regeneration blastema where by 4 days post-amputation the blastema is already divided into distinct growth zones; the cells of each zone are already specified to give rise to upper arm, lower arm, and hand. PMID:15733667

  19. Ethics and embryos.

    PubMed Central

    Poplawski, N; Gillett, G

    1991-01-01

    In this paper we argue that the human form should be seen to exist, in a longitudinal way, throughout the continuum of human growth and development. This entails that the moral value of that form, which we link analytically to the adult, interacting, social and rational being, attaches to all phases of human life to some extent. Having established this we discuss the consequences it has for the moral status of the human embryo. We then apply this argument, and the resulting moral status, to the area of reproductive technology. In doing this we show that there are certain regulations and controls which ought to apply to the use of these infertility treatments. PMID:1870084

  20. Geometric Morphometrics on Gene Expression Patterns Within Phenotypes: A Case Example on Limb Development

    PubMed Central

    Martínez-Abadías, Neus; Mateu, Roger; Niksic, Martina; Russo, Lucia; Sharpe, James

    2016-01-01

    How the genotype translates into the phenotype through development is critical to fully understand the evolution of phenotypes. We propose a novel approach to directly assess how changes in gene expression patterns are associated with changes in morphology using the limb as a case example. Our method combines molecular biology techniques, such as whole-mount in situ hybridization, with image and shape analysis, extending the use of Geometric Morphometrics to the analysis of nonanatomical shapes, such as gene expression domains. Elliptical Fourier and Procrustes-based semilandmark analyses were used to analyze the variation and covariation patterns of the limb bud shape with the expression patterns of two relevant genes for limb morphogenesis, Hoxa11 and Hoxa13. We devised a multiple thresholding method to semiautomatically segment gene domains at several expression levels in large samples of limb buds from C57Bl6 mouse embryos between 10 and 12 postfertilization days. Besides providing an accurate phenotyping tool to quantify the spatiotemporal dynamics of gene expression patterns within developing structures, our morphometric analyses revealed high, non-random, and gene-specific variation undergoing canalization during limb development. Our results demonstrate that Hoxa11 and Hoxa13, despite being paralogs with analogous functions in limb patterning, show clearly distinct dynamic patterns, both in shape and size, and are associated differently with the limb bud shape. The correspondence between our results and already well-established molecular processes underlying limb development confirms that this morphometric approach is a powerful tool to extract features of development regulating morphogenesis. Such multilevel analyses are promising in systems where not so much molecular information is available and will advance our understanding of the genotype–phenotype map. In systematics, this knowledge will increase our ability to infer how evolution modified a common

  1. Effects of apomorphine and haloperidol on response suppression learning of young chicks.

    PubMed

    McDougall, S A; Zolman, J F; Mattingly, B A

    1987-04-01

    In four experiments, the effects of augmenting or blocking dopamine receptor activity on response suppression learning of Colburn X Colburn chicks were determined. In each experiment, 4-day-old chicks were trained to key peck for heat reward and then tested for response suppression learning by using either a response-contingent punishment or an extinction-punishment task. Before response suppression testing, different groups of chicks were injected ip with apomorphine (1.0, 2.0, or 4.0 mg/kg) either alone or after pretreatment with haloperidol (0.5 or 1.0 mg/kg). Regardless of the response suppression task used, chicks injected with apomorphine had difficulty inhibiting their responding; whereas, chicks injected with haloperidol, either alone or before apomorphine treatment, responded on fewer trials than saline-treated chicks. During extinction testing, 4-day-old chicks given only apomorphine showed the typical suppressive effect of punishment on responding rather than the paradoxical punishment-induced increase in responding found in normal 1-day-old chicks. These results indicate that activation of dopamine receptors retards response suppression learning of the 4-day-old chick, but functional changes in central dopaminergic mechanisms are not primarily responsible for the normal age-dependent improvement in response suppression learning of the young chick. PMID:3580128

  2. Dietary supplementation with a probiotic fermented four-herb combination enhances immune activity in broiler chicks and increases survivability against Salmonella Gallinarum in experimentally infected broiler chicks.

    PubMed

    Jung, Bock-Gie; Ko, Jae-Hyung; Lee, Bong-Joo

    2010-12-01

    Herbs including Curcuma longa, Houttuynia cordata, Prunus mume and Rubus coreanus have potential immune enhancing and antimicrobial effects. Probiotics also have antibacterial effects, and some are important in regulating the immune system. The aims of the present study were to evaluate the immune enhancing effects of a probiotic fermented four-herb combination (PFH) in broiler chicks and to demonstrate the prophylactic effect of PFH against Salmonella Gallinarum in experimentally infected broiler chicks as an initial step towards the development of feed supplements for promotion of immune activity and disease prevention. Continuous ingestion of PFH markedly increased lysozyme activity in serum and the spleen, peripheral blood mononuclear cell (PBMC) proliferation, the CD4(+):CD8(+) T lymphocyte ratio in the spleen and antibody production level in broiler chicks. Conversely, prostaglandin E(2) synthesis in serum and PBMC culture medium was significantly decreased in the PFH-fed chicks compared with the control group in a dose-dependent manner. In the chicks experimentally infected with S. Gallinarum, mortality was delayed in the 2% PFH-fed chicks. Moreover, the survival rates in the 2% PFH-fed group remained the highest among all the trial groups throughout the experimental period. Taken together, these findings suggest that PFH enhances immune activity in broiler chicks and increases survivability against Salmonella Gallinarum in experimentally infected broiler chicks, likely because of potent stimulation of nonspecific immune responses. PMID:20675965

  3. Differences in egg nutrient availability, development, and nutrient metabolism of broiler and layer embryos.

    PubMed

    Nangsuay, A; Molenaar, R; Meijerhof, R; van den Anker, I; Heetkamp, M J W; Kemp, B; van den Brand, H

    2015-03-01

    Selection for production traits of broilers and layers leads to physiological differences, which may already be present during incubation. This study aimed to investigate the influence of strain (broiler vs layer) on egg nutrient availability, embryonic development and nutrient metabolism. A total of 480 eggs with an egg weight range of 62.0 to 64.0 g from Lohmann Brown Lite and Ross 308 breeder flocks of 41 or 42 weeks of age were selected in two batches of 120 eggs per batch per strain. For each batch, 30 eggs per strain were used to determine egg composition, including nutrient and energy content, and 90 eggs per strain were separately incubated in one of two climate respiration chambers at an eggshell temperature of 37.8°C. The results showed that broiler eggs had a higher ratio of yolk: albumen with 2.41 g more yolk and 1.48 g less albumen than layers. The yolk energy content of broiler eggs was 46.32 kJ higher than that of layer eggs, whereas total energy content of broiler eggs was 47.85 kJ higher compared to layer eggs. Yolk-free body mass at incubation day 16 and chick weight and length at hatch were higher in broilers compared to layers. Respiration quotient of broiler embryos was higher than layer embryos during incubation day 8 to incubation day 10. A 0.24 g lower residual yolk at the hatch of broiler embryos than for the layer embryos indicated that broiler embryos used more yolk and had a higher energy utilization and energy deposition in yolk-free body mass. Heat production of broiler embryos was higher than that of layer embryos from incubation day 12 to incubation day 18, but efficiency of converting egg energy used by embryos to form yolk-free body mass was similar. In conclusion, broiler and layer embryos have different embryonic development patterns, which affect energy utilization and embryonic heat production. However, the embryos are equal in efficiency of converting the energy used to yolk-free body mass.

  4. Post-translational control of collagen fibrillogenesis in mineralizing cultures of chick osteoblasts

    NASA Technical Reports Server (NTRS)

    Gerstenfeld, L. C.; Riva, A.; Hodgens, K.; Eyre, D. R.; Landis, W. J.

    1993-01-01

    Cultured osteoblasts from chick embryo calvaria were used as a model system to investigate the post-translational extracellular mechanisms controlling the macroassembly of collagen fibrils. The results of these studies demonstrated that cultured osteoblasts secreted a collagenous extracellular matrix that assembled and mineralized in a defined temporal and spatial sequence. The assembly of collagen occurred in a polarized fashion, such that successive orthogonal arrays of fibrils formed between successive cell layers proceeding from the culture surface toward the media. Mineralization followed in the same manner, being observed first in the deepest and oldest fibril layers. Collagen fibrillogenesis, the kinetics of cross-link formation, and collagen stability in the extracellular matrix of the cultures were examined over a 30 day culture period. Between days 8 and 12 in culture, collagen fibril diameters increased from < 30 nm to an average of 30-45 nm. Thereafter, diameters ranged in size from 20 to 200 nm. Quantitation of the collagen cross-linking residues, hydroxylysyl pyridinoline (HP) and lysyl pyridinoline (LP), showed that these mature cross-links increased from undetectable levels to concentrations found in normal chick bone. Analysis of the kinetics of their formation by pulse-chase labeling the cultures with [3H]lysine showed a doubling time of approximately 5 days. The relationships between cross-link formation, fibrillogenesis, and collagen stability were examined in cultures treated with beta-aminopropionitrile (beta-APN), a potent inhibitor of lysyl oxidase and cross-link formation. In beta-APN-treated cultures, total collagen synthesis was increased twofold, with no change in mRNA levels for type I collagen, whereas the amount of collagen accumulated in the cell layer was decreased by 50% and mineral deposition was reduced. The rate of collagen retention in the matrix was assessed by pulse-chase analysis of [3H]proline over a 16 day period in

  5. Newly hatched chicks solve the visual binding problem.

    PubMed

    Wood, Justin N

    2014-07-01

    For an organism to perceive coherent and unified objects, its visual system must bind color and shape features into integrated color-shape representations in memory. However, the origins of this ability have not yet been established. To examine whether newborns can build an integrated representation of the first object they see, I raised newly hatched chicks (Gallus gallus) in controlled-rearing chambers that contained a single virtual object. This object rotated continuously, revealing a different color and shape combination on each of its two faces. Chicks were able to build an integrated representation of this object. For example, they reliably distinguished an object defined by a purple circle and yellow triangle from an object defined by a purple triangle and yellow circle. This result shows that newborns can begin binding color and shape features into integrated representations at the onset of their experience with visual objects. PMID:24840718

  6. Quantitation of the Bioenergetics of a Tuberculosis Infection in Chicks

    PubMed Central

    Squibb, R. L.; Solotorovsky, M.; Beisel, W. R.

    1972-01-01

    Interaction of an avian tuberculosis infection with a known metabolizable energy yield of dietary corn oil in chicks was used to quantitate total host energy expenditure necessitated by the infectious process. Three trials in which two doses of inoculum were used resulted in mild and severe involvements. Trial 1 (mild) indicated that 6% and trials 2 and 3 (severe) that 96 and 93% of the energy supplied by known quantities of corn oil were utilized by the tuberculosis process. In the birds given the low level of inoculum, the degree of tuberculosis involvement, as measured by increased liver size, was correlated with increased total quantities of hepatic ribonucleic acid, monoglycerides, free fatty acids, free cholesterol, and glucose. All of these effects were observed prior to manifestations of clinical symptoms or failure of the chicks to consume all food offered. PMID:4650598

  7. Nutritional value of feather-meal protein for chicks.

    PubMed

    Bielorai, R; Iosif, B; Neumark, H; Alumot, E

    1982-02-01

    Ileal absorption of nitrogen was determined for feather meal (FM) samples, using magnesium ferrite as a marker. Diets containing 15% FM were balanced by linear programming, using two nitrogen absorption values for FM: 55%, as found, or 85%, an average value for standard feeds. When nitrogen absorption of FM was calculated as 55%, the growth of chicks from one to three weeks of age was similar to that of the control chicks. Depression of growth occurred when the diet composition was calculated using 85% nitrogen absorption for FM. The official method of pepsin digestibility in vitro, using 0.2% pepsin, did not reflect the nutritive value of FM protein. Results similar to those of nitrogen absorption in vivo were obtained with 0.002% pepsin. The total cystine content of FM and the rate of its liberation by pancreatin may also seve as an indication of the nutritive value of FM protein.

  8. Percutaneous isolated limb perfusion with thrombolytics for severe limb ischemia.

    PubMed

    Ali, Ahsan T; Kalapatapu, Venkat R; Bledsoe, Shelly; Moursi, Mohammed M; Eidt, John F

    2005-01-01

    Patients with severe tibioperoneal disease are poor candidates for a distal bypass. Absence of a distal target, lack of conduit, or multiple medical problems can make these patients a prohibitive risk for revascularization. Acute on chronic ischemia in this group poses a greater challenge. Thrombolytic therapy for acute ischemia can be prolonged and carries a significant risk of bleeding if continued beyond 24 hours. However, if the ischemic limbs can be isolated from the systemic circulation, a higher dose of the lytic agent can be given with lower risk. These are the initial results of a series of 10 patients who underwent percutaneous isolated limb perfusion with a high dose of thrombolytics for severe ischemia. Ten patients (lower extremity 8 and upper extremity 2) presented with severe limb-threatening ischemia. Mean ankle/brachial index (ABI) was 0.15 for the lower extremity, and there were no recordable digital pressures in patients with upper extremity ischemia. No distal target was visible on the initial arteriogram. These patients were then taken to the operating room, and under anesthesia, catheters were placed in an antegrade fashion via femoral approach in the popliteal artery and vein percutaneously. For upper extremity, the catheters were placed in the brachial artery and vein. A proximal tourniquet was then applied. This isolated the limb from the systemic circulation. Heparinized saline was infused through the arterial catheter while the venous catheter was left open. A closed loop or an isolated limb perfusion was confirmed when effluent became clear coming out of the venous port. A high dose of thrombolytic agent (urokinase 500,000 to 1,000,000 U) was infused into the isolated limb via the arterial catheter and drained out of the venous catheter. After 45 minutes, arterial flow was reestablished. In 4 patients, Reopro((R)) was used in addition to thrombolytics. Postprocedure angiograms showed minimal changes, but patients exhibited marked

  9. Interactions among dietary boron, molybdenum, and magnesium in the chick

    SciTech Connect

    Hunt, C.D.; Nielsen, F.H.

    1986-03-01

    The authors have previously reported that dietary B affects plasma Mo concentrations in chicks fed inadequate levels of Mg and cholecalciferol (vit. D/sub 3/). Because of this finding, they studied the effect of dietary Mo and Mg on the signs of B deficiency in vit. D/sub 3/ deprived chicks. In a fully crossed, 2 x 2 x 2 factorially arranged experiment, day-old cockerel chicks (19 per group) were fed a ground corn-casein-corn oil based diet (containing 0.850 mg B, 0.319 mg Mo, and 125 IU vit. D/sub 3//kg) supplemented with B at 0 or 3 mg/kg, Mo at 0 or 20 mg/kg, and Mg at 300 or 500 mg/kg. After four weeks, B deprivation depressed growth and elevated the plasma glucose and the brain wt/body wt ratio. Low dietary Mo elevated the heart wt/body wt ratio. An interaction between B and Mg affected hemoglobin and plasma alkaline phosphatase and an interaction between B and Mo affected the heart wt/body wt and liver wt/body wt ratios. Mg deficiency gave usual signs including depressed growth, plasma alkaline phosphatase, glucose, and spleen and liver wt/body wt ratios and elevated hematocrit and brain wt/body wt ratio. The findings suggest that physiological levels of Mg and Mo affect B metabolism. The effects of low dietary Mo on vit. D/sub 3/ and/or Mg-deficient chicks needs to be elucidated.

  10. Ontogeny of muscle bioenergetics in Adelie penguin chicks (Pygoscelis adeliae).

    PubMed

    Fongy, Anaïs; Romestaing, Caroline; Blanc, Coralie; Lacoste-Garanger, Nicolas; Rouanet, Jean-Louis; Raccurt, Mireille; Duchamp, Claude

    2013-11-01

    The ontogeny of pectoralis muscle bioenergetics was studied in growing Adélie penguin chicks during the first month after hatching and compared with adults using permeabilized fibers and isolated mitochondria. With pyruvate-malate-succinate or palmitoyl-carnitine as substrates, permeabilized fiber respiration markedly increased during chick growth (3-fold) and further rose in adults (1.4-fold). Several markers of muscle fiber oxidative activity (cytochrome oxidase, citrate synthase, hydroxyl-acyl-CoA dehydrogenase) increased 6- to 19-fold with age together with large rises in intermyofibrillar (IMF) and subsarcolemmal (SS) mitochondrial content (3- to 5-fold) and oxidative activities (1.5- to 2.4-fold). The proportion of IMF relative to SS mitochondria increased with chick age but markedly dropped in adults. Differences in oxidative activity between mitochondrial fractions were reduced in adults compared with hatched chicks. Extrapolation of mitochondrial to muscle respirations revealed similar figures with isolated mitochondria and permeabilized fibers with carbohydrate-derived but not with lipid-derived substrates, suggesting diffusion limitations of lipid substrates with permeabilized fibers. Two immunoreactive fusion proteins, mitofusin 2 (Mfn2) and optic atrophy 1 (OPA1), were detected by Western blots on mitochondrial extracts and their relative abundance increased with age. Muscle fiber respiration was positively related with Mfn2 and OPA1 relative abundance. Present data showed by two complementary techniques large ontogenic increases in muscle oxidative activity that may enable birds to face thermal emancipation and growth in childhood and marine life in adulthood. The concomitant rise in mitochondrial fusion protein abundance suggests a role of mitochondrial networks in the skeletal muscle processes of bioenergetics that enable penguins to overcome harsh environmental constraints.

  11. New techniques on embryo manipulation.

    PubMed

    Escribá, M J; Valbuena, D; Remohí, J; Pellicer, A; Simón, C

    2002-01-01

    For many years, experience has been accumulated on embryo and gamete manipulation in livestock animals. The present work is a review of these techniques and their possible application in human embryology in specific cases. It is possible to manipulate gametes at different levels, producing paternal or maternal haploid embryos (hemicloning), using different techniques including nuclear transfer. At the embryonic stage, considering practical, ethical and legal issues, techniques will be reviewed that include cloning and embryo splitting at the cleavage stage, morula, or blastocyst stage.

  12. Cryobiological preservation of Drosophila embryos

    SciTech Connect

    Mazur, P.; Schreuders, P.D.; Cole, K.W.; Hall, J.W. ); Mahowald, A.P. )

    1992-12-18

    The inability to cryobiologically preserve the fruit fly Drosophila melanogaster has required that fly stocks be maintained by frequent transfer of adults. This method is costly in terms of time and can lead to loss of stocks. Traditional slow freezing methods do not succeed because the embryos are highly sensitive to chilling. With the procedures described here, 68 percent of precisely staged 15-hour Oregon R (wild-type) embryos hatch after vitrification at -205[degree]C, and 40 percent of the resulting larvae develop into normal adult flies. These embryos are among the most complex organisms successfully preserved by cryobiology.

  13. Thalidomide-induced limb abnormalities in a humanized CYP3A mouse model.

    PubMed

    Kazuki, Yasuhiro; Akita, Masaharu; Kobayashi, Kaoru; Osaki, Mitsuhiko; Satoh, Daisuke; Ohta, Ryo; Abe, Satoshi; Takehara, Shoko; Kazuki, Kanako; Yamazaki, Hiroshi; Kamataki, Tetsuya; Oshimura, Mitsuo

    2016-02-23

    Thalidomide is a teratogen in humans but not in rodents. It causes multiple birth defects including malformations of limbs, ears, and other organs. However, the species-specific mechanism of thalidomide teratogenicity is not completely understood. Reproduction of the human teratogenicity of thalidomide in rodents has previously failed because of the lack of a model reflecting human drug metabolism. In addition, because the maternal metabolic effect cannot be eliminated, the migration of unchanged thalidomide to embryos is suppressed, and the metabolic activation is insufficient to develop teratogenicity. Previously, we generated transchromosomic mice containing a human cytochrome P450 (CYP) 3A cluster in which the endogenous mouse Cyp3a genes were deleted. Here, we determined whether human CYP3A or mouse Cyp3a enzyme expression was related to the species difference in a whole embryo culture system using humanized CYP3A mouse embryos. Thalidomide-treated embryos with the human CYP3A gene cluster showed limb abnormalities, and human CYP3A was expressed in the placenta, suggesting that human CYP3A in the placenta may contribute to the teratogenicity of thalidomide. These data suggest that the humanized CYP3A mouse is a useful model to predict embryonic toxicity in humans.

  14. Thalidomide-induced limb abnormalities in a humanized CYP3A mouse model

    PubMed Central

    Kazuki, Yasuhiro; Akita, Masaharu; Kobayashi, Kaoru; Osaki, Mitsuhiko; Satoh, Daisuke; Ohta, Ryo; Abe, Satoshi; Takehara, Shoko; Kazuki, Kanako; Yamazaki, Hiroshi; Kamataki, Tetsuya; Oshimura, Mitsuo

    2016-01-01

    Thalidomide is a teratogen in humans but not in rodents. It causes multiple birth defects including malformations of limbs, ears, and other organs. However, the species-specific mechanism of thalidomide teratogenicity is not completely understood. Reproduction of the human teratogenicity of thalidomide in rodents has previously failed because of the lack of a model reflecting human drug metabolism. In addition, because the maternal metabolic effect cannot be eliminated, the migration of unchanged thalidomide to embryos is suppressed, and the metabolic activation is insufficient to develop teratogenicity. Previously, we generated transchromosomic mice containing a human cytochrome P450 (CYP) 3A cluster in which the endogenous mouse Cyp3a genes were deleted. Here, we determined whether human CYP3A or mouse Cyp3a enzyme expression was related to the species difference in a whole embryo culture system using humanized CYP3A mouse embryos. Thalidomide-treated embryos with the human CYP3A gene cluster showed limb abnormalities, and human CYP3A was expressed in the placenta, suggesting that human CYP3A in the placenta may contribute to the teratogenicity of thalidomide. These data suggest that the humanized CYP3A mouse is a useful model to predict embryonic toxicity in humans. PMID:26903378

  15. Acephate immunotoxicity in White Leghorn cockerel chicks upon experimental exposure

    USGS Publications Warehouse

    Tripathi, Syamantak Mani; Thaker, A. M.; Joshi, C. G.; Sankhala, Laxmi Narayan

    2012-01-01

    Immunotoxicity for subacute exposure to acephate (O,S-dimethyl-acetylphosphoramidothioate) was assessed in day old White Leghorn (WLH) cockerel chicks. The chicks were divided into five groups. Groups C1 and C2 served as plain control and vehicle control respectively. Chicks of groups T1, T2 and T3 were administered acephate suspended in groundnut oil at 21.3 mg/kg, 28.4 mg/kg and 42.6 mg/kg respectively orally for 28 days. A non-significant reduction in total leukocyte count was observed. Although, anti-Newcastle Disease Virus (NDV) antibody titer, serum total protein (TP), serum globulin, serum albumin and organ:body weight ratios of immune organs were significantly suppressed. The delayed type hypersensitivity response to 2,4-dinitro-1-chlorobenzene (DNCB) was not significantly altered. Histopathologically, bursa and spleen showed mild depletion of lymphocytes. Furthermore, DNA fragmentation assay was performed and detected ladder pattern (180 bp) in DNA. It was concluded that subacute acephate exposure at low concentrations may affect immune responses in avian species.

  16. Deleterious effects of magnesium intoxication upon the domestic broiler chick

    SciTech Connect

    Lee, S.R.

    1984-01-01

    Dietary levels of 0.6 to 0.8% magnesium in a corn-soy basal were rachitogenic. These rickets appeared most like phosphorus deficiency. Bone Ca/P ratios were numerically quite low implying a lack of transformation from amorphous calcium phosphate to hydroxyapatite. Bone alkaline phosphatase activity was elevated. Additional dietary phosphorus ameliorated, but could not overcome the rachitogenic effects of magnesium. Tibial dyschondroplasia (TD), induced by elevated dietary P, was decreased by high levels of dietary Mg, but with no decrease in plasma phosphorus. Anticoccidial ionophores fed in conjunction with a moderate dietary challenge of Mg (0.48%) produced no clear changes in plasma calcium or Mg, but did interact to reduce body weight. The diarrhea caused by magnesium intoxication is not due to hyperosmotic loads of Mg per se. Rather, Cl was observed to be the major ionic constituent of the gut osmotic load implying different gut ionic fluxes in control versus magnesium intoxicated chicks. These data imply that the cathartic action of Mg is due to hypersecretion of the gut. Effects mediated or modified by the CNS changed in magnesium intoxicated chicks. Such chicks appeared cold and stayed near the heat. When startled, they exhibited extreme avoidance behavior and seizures similar to epilepsy and/or Cl deficiency. Brain tissue Mg content did not concomitantly increase. Whether these effects are due to central signals is unclear.

  17. Numerical abstraction in young domestic chicks (Gallus gallus).

    PubMed

    Rugani, Rosa; Vallortigara, Giorgio; Regolin, Lucia

    2013-01-01

    In a variety of circumstances animals can represent numerical values per se, although it is unclear how salient numbers are relative to non-numerical properties. The question is then: are numbers intrinsically distinguished or are they processed as a last resort only when no other properties differentiate stimuli? The last resort hypothesis is supported by findings pertaining to animal studies characterized by extensive training procedures. Animals may, nevertheless, spontaneously and routinely discriminate numerical attributes in their natural habitat, but data available on spontaneous numerical competence usually emerge from studies not disentangling numerical from quantitative cues. In the study being outlined here, we tested animals' discrimination of a large number of elements utilizing a paradigm that did not require any training procedures. During rearing, newborn chicks were presented with two stimuli, each characterized by a different number of heterogeneous (for colour, size and shape) elements and food was found in proximity of one of the two stimuli. At testing 3 day-old chicks were presented with stimuli depicting novel elements (for colour, size and shape) representing either the numerosity associated or not associated with food. The chicks approached the number associated with food in the 5vs.10 and 10vs.20 comparisons both when quantitative cues were unavailable (stimuli were of random sizes) or being controlled. The findings emerging from the study support the hypothesis that numbers are salient information promptly processed even by very young animals.

  18. Social influences of competition on impulsive choices in domestic chicks.

    PubMed

    Amita, Hidetoshi; Kawamori, Ai; Matsushima, Toshiya

    2010-04-23

    Social factors involved in the control of impulsiveness were examined in domestic chicks. In binary choices between a large/long-delay option (LL) and a small/short-delay alternative (SS), chicks that had been competitively trained in groups of three individuals showed fewer choices of LL than did those trained in isolation (experiment 1), suggesting that competition causes impulsive choice. In experiment 2, in order to identify the critical factor involved, we tested the effects of perceived competition (coincident feeding without interruption) and scrounging (gaining food without pecking bead) separately. To examine the effects of risk/noise that individual chicks experienced in competition, the food amount varied randomly in trials according to a binomial distribution around the expected mean. Perceived competition primarily contributed to the influence on the impulsive choice, whereas the contribution of scrounging was weaker. Collection risk did not explain the social influences since the perceived competition was not accompanied by actual interruption of the delayed food reward. The risk owing to variable food per se did not cause impulsive choices. Coincident foraging during competition is thought to play a critical role.

  19. [Evaluation of Antilles fish ciguatoxicity by mouse and chick bioassays].

    PubMed

    Pottier, I; Vernoux, J P

    2003-03-01

    Ciguatera is a common seafood poisoning in Western Atlantic and French West Indies. Ciguatera fish poisoning in the Caribbean is a public health problem. A toxicological study was carried out on 178 Caribbean fish specimens (26 species) captured off Guadeloupe and Saint Barthelemy between 1993 and 1999. The mouse bioassay and the chick feeding test were used to control fish edibility. Ciguatoxins presence was assumed when symptomatology was typical of ciguatera in mouse and chick. Fishes were classified in three groups: non toxic fish (edible), low toxic fish (not edible) and toxic fish (not edible). 75% of fishes were non toxic. Toxic fish specimens belonged to four families of high trophic level carnivores: Carangidae, Lutjanidae, Serranidae et Sphyraenidae. Percentages of toxic fishes to humans reached 55% for Caranx latus and 33% for Caranx bartholomaei and Caranx lugubris. Only a significant correlation between weight and toxicity was only found for C. latus and snappers. Small carnivorous groupers (Serranidae) were also toxic. Atoxic fish species were (a) pelagic fish (Coryphaena hippurus, Auxis thazard and Euthynnus pelamis), (b) invertebrates feeders (Malacanthus plumieri, Balistes vetula), (c) small high-risk fish or (d) fish of edible benthic fish families. Liver of four fishes (Mycteroperca venenosa, Caranx bartholomaei, Seriola rivoliana, Gymnothorax funebris) contained ciguatoxins at a significant level although their flesh was safe. This study confirms the usefulness of mouse and chick bioassays for sanitary control of fish. PMID:12784589

  20. Energy utilization and heat production of embryos from eggs originating from young and old broiler breeder flocks.

    PubMed

    Nangsuay, A; Meijerhof, R; Ruangpanit, Y; Kemp, B; van den Brand, H

    2013-02-01

    Two experiments were conducted to study the interaction between breeder age and egg size on the energy utilization (experiment 1) and heat production (experiment 2) of broiler embryos. In experiment 1, a total of 4,800 Ross-308 hatching eggs from 2 breeder ages (29 and 53 wk of age, or young and old) and, within each age, 2 egg sizes (57 to 61 g and 66 to 70 g, or small and large) were used. In experiment 2, a total of 240 Ross-308 hatching eggs from 2 breeder flocks at 29 (young) and 53 (old) wk of age, and which were selected from the same egg weight range (58 to 61 g), were tested in 2 replicate chambers. In experiment 1, it was shown that the amount of yolk relative to albumen was higher in the old flock eggs, and this effect was more pronounced in the large eggs. The old flock eggs, especially the larger egg size, contained more energy as a result of a greater yolk size. Energy utilization of the embryos was positively related to yolk size and the amount of energy transferred to yolk-free body (YFB) was largely determined by the available egg energy. The efficiency of converting egg energy into chick body energy (E(YFB)) was equal for both egg sizes and both breeder age groups. Chick YFB weight of young and old flock eggs was equal. However, dry YFB weight of chicks from old flock eggs was higher than in chicks from young flock eggs, which was associated with more protein and fat content and thus more energy accumulated into YFB. As a consequence, embryos derived from old flock eggs produced more heat from d 16 of incubation onward than those of the young flock eggs. In conclusion, the higher energy deposition into chick YFB of old flock eggs, leading to higher embryonic heat production, is the result of a higher amount of available energy in the egg and is not due to changes in E(YFB).

  1. Interactive and Vicarious Acquisition of Auditory Preferences in Northern Bobwhite (Colinus virginianus) Chicks

    PubMed Central

    Harshaw, Christopher; Lickliter, Robert

    2008-01-01

    Studies examining the effects of stimulus contingency on filial imprinting have produced inconsistent findings. In the current study, day-old bobwhite chicks (Colinus virginianus) received individual 5-min sessions in which they were provided contingent, noncontingent, or vicarious exposure to a variant of a bobwhite maternal assembly call. Chicks given contingent exposure to the call showed a significant preference for the familiar call 24 hr following exposure and significantly greater preferences than chicks given noncontingent exposure. Chicks given vicarious exposure to recordings of another chick interacting with the maternal call showed significant deviations from chance responding; however, the direction of chick preference (toward the familiar or unfamiliar) depended on the particular call used. These results indicate that both direct and indirect (vicarious) exposure to stimulus contingency can enhance the acquisition of auditory preferences in precocial avian hatchlings. Precocial avian hatchlings thus likely play a more active role in directing their own perceptual and behavioral development than has typically been thought. PMID:17696658

  2. Efficiency of the cloacal sexing technique in greater rhea chicks (Rhea americana).

    PubMed

    Bazzano, G; Lèche, A; Martella, M B; Navarro, J L

    2012-01-01

    1. The feasibility and accuracy of the cloacal sexing technique in greater rhea chicks was assessed using chicks of two captive populations of greater rhea in Córdoba, Argentina. 2. A total of 46 greater rhea chicks of 2 to 3 months of age were randomly arranged into three groups and the members of each group were sexed by a different operator. 3. A feather of each chick was plucked for sexing through a molecular method and results were used as controls. 4. Sex was correctly assigned by cloacal inspection in 98% of the cases. Chick manipulation was easily performed and no infections or traumatic lesions were observed a posteriori. 5. Cloacal sexing of rhea chicks up to 3 months of age does not affect animal welfare and should be considered an efficient alternative to molecular methods.

  3. Ion currents in embryo development.

    PubMed

    Tosti, Elisabetta; Boni, Raffaele; Gallo, Alessandra

    2016-03-01

    Ion channels are proteins expressed in the plasma membrane of electrogenic cells. In the zygote and blastomeres of the developing embryo, electrical modifications result from ion currents that flow through these channels. This phenomenon implies that ion current activity exerts a specific developmental function, and plays a crucial role in signal transduction and the control of embryogenesis, from the early cleavage stages and during growth and development of the embryo. This review describes the involvement of ion currents in early embryo development, from marine invertebrates to human, focusing on the occurrence, modulation, and dynamic role of ion fluxes taking place on the zygote and blastomere plasma membrane, and at the intercellular communication between embryo cell stages.

  4. The phantom limb in dreams.

    PubMed

    Brugger, Peter

    2008-12-01

    Mulder and colleagues [Mulder, T., Hochstenbach, J., Dijkstra, P. U., Geertzen, J. H. B. (2008). Born to adapt, but not in your dreams. Consciousness and Cognition, 17, 1266-1271.] report that a majority of amputees continue to experience a normally-limbed body during their night dreams. They interprete this observation as a failure of the body schema to adapt to the new body shape. The present note does not question this interpretation, but points to the already existing literature on the phenomenology of the phantom limb in dreams. A summary of published investigations is complemented by a note on phantom phenomena in the dreams of paraplegic patients and persons born without a limb. Integration of the available data allows the recommendation for prospective studies to consider dream content in more detail. For instance, "adaptation" to the loss of a limb can also manifest itself by seeing oneself surrounded by amputees. Such projective types of anosognosia ("transitivism") in nocturnal dreams should also be experimentally induced in normally-limbed individuals, and some relevant techniques are mentioned.

  5. Conserved and divergent expression patterns of markers of axial development in reptilian embryos: Chinese soft-shell turtle and Madagascar ground gecko.

    PubMed

    Yoshida, Michio; Kajikawa, Eriko; Kurokawa, Daisuke; Noro, Miyuki; Iwai, Tatsuhiro; Yonemura, Shigenobu; Kobayashi, Kensaku; Kiyonari, Hiroshi; Aizawa, Shinichi

    2016-07-01

    The processes of development leading up to gastrulation have been markedly altered during the evolution of amniotes, and it is uncertain how the mechanisms of axis formation are conserved and diverged between mouse and chick embryos. To assess the conservation and divergence of these mechanisms, this study examined gene expression patterns during the axis formation process in Chinese soft-shell turtle and Madagascar ground gecko preovipositional embryos. The data suggest that NODAL signaling, similarly to avian embryos but in contrast to eutherian embryos, does not have a role in epiblast and hypoblast development in reptilian embryos. The posterior marginal epiblast (PME) is the initial molecular landmark of axis formation in reptilian embryos prior to primitive plate development. Ontogenetically, PME may be the precursor of the primitive plate, and phylogenetically, Koller's sickle and posterior marginal zone in avian development may have been derived from the PME. Most of the genes expressed in the mouse anterior visceral endoderm (AVE genes), especially signaling antagonist genes, are not expressed in the hypoblast of turtle and gecko embryos, though they are expressed in the avian hypoblast. This study proposes that AVE gene expression in the hypoblast and the visceral endoderm could have been independently established in avian and eutherian lineages, similar to the primitive streak that has been independently acquired in these lineages. PMID:27174471

  6. Conserved and divergent expression patterns of markers of axial development in reptilian embryos: Chinese soft-shell turtle and Madagascar ground gecko.

    PubMed

    Yoshida, Michio; Kajikawa, Eriko; Kurokawa, Daisuke; Noro, Miyuki; Iwai, Tatsuhiro; Yonemura, Shigenobu; Kobayashi, Kensaku; Kiyonari, Hiroshi; Aizawa, Shinichi

    2016-07-01

    The processes of development leading up to gastrulation have been markedly altered during the evolution of amniotes, and it is uncertain how the mechanisms of axis formation are conserved and diverged between mouse and chick embryos. To assess the conservation and divergence of these mechanisms, this study examined gene expression patterns during the axis formation process in Chinese soft-shell turtle and Madagascar ground gecko preovipositional embryos. The data suggest that NODAL signaling, similarly to avian embryos but in contrast to eutherian embryos, does not have a role in epiblast and hypoblast development in reptilian embryos. The posterior marginal epiblast (PME) is the initial molecular landmark of axis formation in reptilian embryos prior to primitive plate development. Ontogenetically, PME may be the precursor of the primitive plate, and phylogenetically, Koller's sickle and posterior marginal zone in avian development may have been derived from the PME. Most of the genes expressed in the mouse anterior visceral endoderm (AVE genes), especially signaling antagonist genes, are not expressed in the hypoblast of turtle and gecko embryos, though they are expressed in the avian hypoblast. This study proposes that AVE gene expression in the hypoblast and the visceral endoderm could have been independently established in avian and eutherian lineages, similar to the primitive streak that has been independently acquired in these lineages.

  7. Standardization of grading embryo morphology.

    PubMed

    Racowsky, Catherine; Vernon, Michael; Mayer, Jacob; Ball, G David; Behr, Barry; Pomeroy, Kimball O; Wininger, David; Gibbons, William; Conaghan, Joseph; Stern, Judy E

    2010-08-01

    Standardization of morphologic assessment for an embryo grading system was developed and is being implemented by the Society for Assisted Reproductive Technology (SART). A recent European consensus conference of embryologists from Europe and America is working toward adopting an embryo classification system modeled similarly to that of SART that, if adopted, would produce a de facto international standard to aid cross-border collaboration. PMID:20580357

  8. Indirect cannibalism by crèche-aged American White Pelican (Pelecanus erythrorhynchos) chicks

    USGS Publications Warehouse

    Bartos, Alisa J.; Sovada, Marsha A.; Igl, Lawrence D.; Pietz, Pamela J.

    2013-01-01

    At nesting colonies of American White Pelicans (Pelecanus erythrorhynchos), many chicks die from siblicide, severe weather, and disease; this results in carcasses available for scavenging by conspecifics (i.e., indirect cannibalism). Indirect cannibalism has not been reported previously for this species. We describe five cases of crèche-aged American White Pelican chicks consuming or attempting to consume dead younger chicks at two nesting colonies in the northern plains of North America. Cannibalism in the American White Pelican appears to be rare and likely plays no role in the species’ population ecology or dynamics; however, it might be an important survival strategy of individual chicks when food resources are limited.

  9. The effects of ingested plastic on growth and survival of albatross chicks

    USGS Publications Warehouse

    Sievert, Paul R.; Sileo, Louis

    1993-01-01

    We studied the effects of ingested plastic on the growth and survival of chicks of Laysan Albatrosses Diomedea immutabilis and Black-footed albatrosses D. nigripes on Midway Atoll during the nesting seasons of 1986 and 1987. Weights and proventricular contents of the chicks were determined periodically through the nesting cycle. Large (>22 cm1)volumes of plastic were present in the proventriculi of 27% of the Laysan and 16% of the Black-footed albatross chicks examined by endoscopy. Prior to fledging, albatross chicks regurgitated pellets composed of plastic and other indigestible material from their proventriculi. Laysan Albatross chicks with large volumes of proventricular plastic had asymptotic fledging weights significantly lower (122 g) than did chicks with low amounts of plastic. The effect of depresses fledging weights on postfledging survival was not determined. Plastic had no detectable effect on the growth of Black-footed Albatross chicks. All chicks that died were examined by necropsy. Mechanical lesions from ingested plastic were the cause of death of one of 45 Laysan Albatross chicks examined in 1986, but were not the cause of death of 93 individuals examined in 1987. Dehydration was the most common cause of death. In general, ingested plastic was not a significant direct cause of death in nestlings, but there was some evidence that it may have affected survival in 1986, when the volume of plastic ingested was highest.

  10. Perinatal broiler physiology between hatching and chick collection in 2 hatching systems.

    PubMed

    van de Ven, L J F; van Wagenberg, A V; Decuypere, E; Kemp, B; van den Brand, H

    2013-04-01

    Little is known about physiological responses of early- versus late-hatching chicks to early posthatch conditions in broiler practice. We investigated effects of hatching time on perinatal broiler physiology in 2 hatching systems, differing in conditions: a conventional hatcher, where chicks are deprived of feed and water between hatching and the moment of chick pulling (d E21.5), and a patio system, in which the hatching and brooding phase are combined, and chicks have immediate posthatch feed and water access. Climate conditions in patio also differ with about 3°C lower temperature and 20% lower RH compared with conventional hatchers. At E18, fertile eggs were transferred to either a hatcher or the patio until the end of incubation. From each system, 50 newly hatched chicks were collected at 3 hatching times: at 468 h (early), 483 h (midterm), and 498 h (late) of incubation, of which 25 chicks were decapitated for analyses of physiological parameters. The other 25 chicks were returned to the hatching system for analyses after 515 h of incubation (E21.5). At hatch, weights of the heart, lungs, stomach, and intestine increased with hatching time, concurrent with a decrease in residual yolk weight, regardless of hatching system, and indicating that later hatching chicks are more matured. Weights of the heart, liver, stomach, and intestines were lower in hatcher than in patio chicks. Between hatch and E21.5, residual yolk weight decreased, whereas organ weights increased in both fasted hatcher and fed patio chicks, but at a higher rate in the latter. At E21.5, plasma glucose and triiodothyronine had increased with time after hatch in patio chicks, whereas levels were similar among hatching times and lower in hatcher chicks. Early feed and water access seems to enable early hatching chicks to compensate for their apparent disadvantage in development at hatching, whereas chicks subjected to fasting show metabolic adaptations to preserve nutrients. Chick physiology at

  11. The adrenocortical stress-response of Black-legged Kittiwake chicks in relation to dietary restrictions

    USGS Publications Warehouse

    Kitaysky, A.S.; Piatt, J.F.; Wingfield, J.C.; Romano, M.

    1999-01-01

    In this study we examined hormonal responses of Black-legged Kittiwake (Rissa tridactyla) chicks to experimental variations in energy content and nutritional quality (low or high lipid to protein ratio, LPR) of their food. Starting at the age of 10 days, chicks were fed either high or low LPR fish at 30, 50, 70 and 100% of ad libitum energy intake. After 20 days of treatment, chicks were exposed to a standardized acute handling and restraint stress protocol, where a baseline sample was taken immediately after taking a chick from the nest, and three additional blood samples were taken at intervals up to 50 min. Testosterone and corticosterone titres in plasma were measured via radioimmunoassay. We found that baseline testosterone levels were not significantly affected by the experimental treatments. Food-restricted chicks had elevated baseline and acute stress-induced levels of corticosterone compared to chicks fed ad libitum. An elevation of circulating levels of corticosterone in energetically stressed individuals was further magnified by low nutritional quality of food. Baseline and acute stress-induced corticosterone levels of chicks were negatively correlated with their fat reserves. We conclude that the physiological condition of Black-legged Kittiwake chicks can be assessed reliably by measuring circulating levels of corticosterone. We discuss short-and long-term effects of elevated corticosterone secretion in food-stressed nest-bound chicks.

  12. Automated lower limb prosthesis design

    NASA Astrophysics Data System (ADS)

    Bhatia, Gulab H.; Commean, Paul K.; Smith, Kirk E.; Vannier, Michael W.

    1994-09-01

    The design of lower limb prostheses requires definitive geometric data to customize socket shape. Optical surface imaging and spiral x-ray computed tomography were applied to geometric analysis of limb residua in below knee (BK) amputees. Residua (limb remnants after amputation) of BK amputees were digitized and measured. Surface (optical) and volumetric (CT) data of the residuum were used to generate solid models and specify socket shape in (SDRC I-DEAS) CAD software. Volume measurements on the solid models were found to correspond within 2% of surface models and direct determinations made using Archimedean weighing. Anatomic 3D reconstruction of the residuum by optical surface and spiral x-ray computed tomography imaging are feasible modalities for prosthesis design.

  13. Congenital Anomalies of the Limbs

    PubMed Central

    Gingras, G.; Mongeau, M.; Moreault, P.; Dupuis, M.; Hebert, B.; Corriveau, C.

    1964-01-01

    As a preparatory step towards the development of a complete habilitation program for children with congenital limb anomalies associated with maternal ingestion of thalidomide, the medical records of all patients with congenital limb anomalies referred to the Rehabilitation Institute of Montreal in the past decade were studied, and an examination and a thorough reassessment were made of 41 patients (21 males and 20 females). In this paper, Part I, the medical and prosthetic aspects are dealt with and a form of management is described for each type of anomaly. The conclusions are reached that prosthetic fitting and training should be initiated very early in life and that co-operation of the parent is essential to successful habilitation of a child with congenital limb anomalies. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7 PMID:14154297

  14. Effect of cadmium injected in ovo on hatching results and the activity of plasma hydrolytic enzymes in newly hatched chicks.

    PubMed

    Dżugan, Małgorzata; Lis, Marcin; Droba, Maria; Niedziółka, Jerzy W

    2011-09-01

    The aim of the study was to determine the toxicity of cadmium ions in chick embryos, using plasma hydrolytic enzyme as its biomarker. Hatching eggs (n = 300) from Ross 308 broilers were incubated under standard conditions. On day 4 of incubation, 50 μl of saline solution, containing Cd ions at a concentration from 0 (control group) to 24 μg, was injected in ovo into the egg albumen. The results indicate that the administration of cadmium at doses exceeding 1 μg/egg caused a gradual decrease in hatchability, with an LD50 of 3.9 μg/egg. The greatest differences between the groups in the enzymatic activities studied were found for N-acetyl-β-D-glucosaminidase (NAG), β-D-mannosidase (β-MAN) and arylsulphatase (ARYL). Compared to the control group, in the blood serum of chicks from the groups receiving 3, 6 and 12 μg Cd/egg the NAG activity increased by 79, 108 and 54% and β-MAN activity by 33, 119 and 108%, respectively. Exposure to cadmium at a dose of 1 to 6 μg per egg caused an about 60% increase in ARYL activity while a dose of 12 μg decreased the activity by about 35% below the level observed in the control group. These findings show that cadmium has a similar toxicity mechanism in mammals and birds, which opens the possibility of using NAG activity as a biomarker of the cytotoxic effect of cadmium in birds.

  15. Apparatus for determining changes in limb volume

    NASA Technical Reports Server (NTRS)

    Bhagat, P. K.; Wu, V. C. (Inventor)

    1981-01-01

    Measuring apparatus for determining changes in the volume of limbs or other boty extremities by determining the cross-sectional area of such limbs many comprise a transmitter including first and second transducers for positioning on the surface of the limb at a predetermined distance there between, and a receiver including a receiver crystal for positioning on the surface of the limb. The distance between the receiver crystal and the first and second transducers are represented by respective first and second chords of the cross-section of the limb and the predetermined distance between the first and second transducers is represented by a third chord of the limb cross section.

  16. Lessons from Embryos: Haeckel's Embryo Drawings, Evolution, and Secondary Biology Textbooks

    ERIC Educational Resources Information Center

    Wellner, Karen L.

    2014-01-01

    In 1997, developmental biologist Michael Richardson compared his research team's embryo photographs to Ernst Haeckel's 1874 embryo drawings and called Haeckel's work "noncredible". "Science" soon published "Haeckel's Embryos: Fraud Rediscovered," and Richardson's comments further reinvigorated criticism of Haeckel by…

  17. Effects of breeder age and egg weight on morphological changes in the small intestine of chicks during the hatch window.

    PubMed

    Yalçin, S; Izzetoğlu, G T; Aktaş, A

    2013-01-01

    1. The objective of the study was to investigate the effects of breeder age and egg weight on hatching performance and morphological changes in segments of the small intestine of broiler chicks during a 21 h hatch window. 2. Eggs from Ross broiler breeder flocks aged 29 (young) and 48 weeks (old) were classified as light (LE) or heavy (HE) and incubated at the same conditions. At 475 h of incubation, eggs were checked every 3 h to determine time of external pipping and hatching. The first 42 chicks to emerge from each group were weighed and chick length was measured and 14 chicks from each group were sampled to collect residual yolk and intestine segments. The rest of chicks were placed back in the incubator and chick weight and length were measured individually at 9, 15 and 21 h after chicks hatched. At the end of 21 h, 14 chicks from each group were sampled again and the same procedure was followed. 3. The HE chicks pipped and hatched later than LE, regardless of breeder age. From hatch to the end of the hatch window, chick weight, but not yolk-free chick weight, gradually reduced. Relative residual yolk weight of chicks from both egg weights was similar at hatch, however, yolk sac utilisation was higher for LE chicks during the 21 h post-hatch period. At hatch, jejunum and ileum villus development was very similar for HE and LE chicks but greater development was observed for villus area with an increase in the jejunum villus length, width and goblet cell numbers in HE chicks. 4. The longest jejunum villus and the widest duodenum and jejunum villus were obtained for HE chicks from old breeders indicating that HE chicks from old breeders would have a greater surface area for nutrient absorption.

  18. Axonal patterns and targets of dA1 interneurons in the chick hindbrain.

    PubMed

    Kohl, Ayelet; Hadas, Yoav; Klar, Avihu; Sela-Donenfeld, Dalit

    2012-04-25

    Hindbrain dorsal interneurons that comprise the rhombic lip relay sensory information and coordinate motor outputs. The progenitor dA1 subgroup of interneurons, which is formed along the dorsal-most region of the caudal rhombic lip, gives rise to the cochlear and precerebellar nuclei. These centers project sensory inputs toward upper-brain regions. The fundamental role of dA1 interneurons in the assembly and function of these brainstem nuclei is well characterized. However, the precise en route axonal patterns and synaptic targets of dA1 interneurons are not clear as of yet. Novel genetic tools were used to label dA1 neurons and trace their axonal trajectories and synaptic connections at various stages of chick embryos. Using dA1-specific enhancers, two contralateral ascending axonal projection patterns were identified; one derived from rhombomeres 6-7 that elongated in the dorsal funiculus, while the other originated from rhombomeres 2-5 and extended in the lateral funiculus. Targets of dA1 axons were followed at later stages using PiggyBac-mediated DNA transposition. dA1 axons were found to project and form synapses in the auditory nuclei and cerebellum. Investigation of mechanisms that regulate the patterns of dA1 axons revealed a fundamental role of Lim-homeodomain (HD) proteins. Switch in the expression of the specific dA1 Lim-HD proteins Lhx2/9 into Lhx1, which is typically expressed in dB1 interneurons, modified dA1 axonal patterns to project along the routes of dB1 subgroup. Together, the results of this research provided new tools and knowledge to the assembly of trajectories and connectivity of hindbrain dA1 interneurons and of molecular mechanisms that control these patterns.

  19. Adrenergic innervation of the developing chick heart: neural crest ablations to produce sympathetically aneural hearts

    SciTech Connect

    Kirby, M.; Stewart, D.

    1984-11-01

    Ablation of various regions of premigratory trunk neural crest which gives rise to the sympathetic trunks was used to remove sympathetic cardiac innervation. Neuronal uptake of (/sup 3/H)-norepinephrine was used as an index of neuronal development in the chick atrium. Following ablation of neural crest over somites 10-15 or 15-20, uptake was significantly decreased in the atrium at 16 and 17 days of development. Ablation of neural crest over somites 5-10 and 20-25 caused no decrease in (/sup 3/H)-norepinephrine uptake. Removal of neural crest over somites 5-25 or 10-20 caused approximately equal depletions of (/sup 3/H)-norepinephrine uptake in the atrium. Cardiac norepinephrine concentration was significantly depressed following ablation of neural crest over somites 5-25 but not over somites 10-20. Light-microscopic and histofluorescent preparations confirmed the absence of sympathetic trunks in the region of the normal origin of the sympathetic cardiac nerves following neural crest ablation over somites 10-20. The neural tube and dorsal root ganglia were damaged in the area of the neural-crest ablation; however, all of these structures were normal cranial and caudal to the lesioned area. Development of most of the embryos as well as the morphology of all of the hearts was normal following the lesion. These results indicate that it is possible to produce sympathetically aneural hearts by neural-crest ablation; however, sympathetic cardiac nerves account for an insignificant amount of cardiac norepinephrine.

  20. Aspects of hatching success and chick survival in Gull-billed Terns in coastal Virginia

    USGS Publications Warehouse

    Eyler, T.B.; Erwin, R.M.; Stotts, D.B.; Hatfield, J.S.

    1999-01-01

    Because of a long-term population decline in Gull-billed Terns (Sterna nilotica) nesting along the coast of Virginia, we began a three year study in 1994 to monitor hatching success and survival of Gull-billed Tern chicks at several Virginia colony sites. Colonies were located on either small, storm-deposited shellpiles along marsh fringes or large, sandshell overwash fans of barrier islands. Nests were monitored one to three times a week for hatching success, and enclosures were installed around selected nests to monitor chick survival from hatching to about two weeks of age. Hatching success was lower in marsh colonies than island colonies, and was lower in 1995 than in 1994 and 1996, primarily because of flooding. The average brood size of nests where at least one chick hatched was 1.99 chicks. Survival rates of chicks to 14 days depended on hatch order and year but not brood size (one vs. two or more) or time of season. A-chicks had higher survival rates than B-chicks and third-hatched C-chicks (0.661 compared to 0.442 and 0.357, respectively). The year effect was significant only for A-chicks, with lower survival in 1994 (0.50) than in 1995 (0.765) or 1996 (0.758). Overall, productivity was low (0.53 chick per nest) compared to estimates for colonies in Denmark, and was attributable to nest flooding by spring and storm-driven high tides and chick predation, presumably mostly by Great Horned Owls (Bubo virginianus).

  1. Changes in free amino acid and monoamine concentrations in the chick brain associated with feeding behavior.

    PubMed

    Tran, Phuong V; Chowdhury, Vishwajit S; Nagasawa, Mao; Furuse, Mitsuhiro

    2015-01-01

    Domesticated chicks are precocial and therefore have relatively well-developed feeding behavior. The role of hypothalamic neuropeptides in food-intake regulation in chicks has been reported for decades. However, we hypothesized that nutrients and their metabolites in the brain may be involved in food intake in chicks because these animals exhibit a very frequent feeding pattern. Therefore, the purpose of this study was to examine the feeding behavior of chicks as well as the associated changes in free amino acid and monoamine concentrations in the chick brain. The feeding behavior of chicks was recorded continuously for 6 h. The next day, brain and blood samples were collected when the chicks either attempted to have food (hungry group) or turned food down (satiated group), in order to analyze the concentrations of the free amino acids and monoamines. We confirmed that the feeding behavior of neonatal chicks was characterized by short resting periods between very brief times spent on food intake. Several free amino acids in the mesencephalon were significantly lower in the satiated group than in the hungry group, while l-histidine and l-glutamine were significantly higher. Notably, there was no change in the free amino acid concentrations in other brain regions or plasma. As for monoamines, serotonin and norepinephrine were significantly lower in the mesencephalon of the hungry group compared with the satiated group, but 5 hydroxyindolacetic acid (5-HIAA) was higher. In addition, serotonin and norepinephrine levels were significantly higher in the brain stem of the hungry chicks compared with the satiated group, but levels of 5-HIAA and homovanillic acid were lower. Levels of both dopamine and its metabolite, 3,4-dihydroxyphenylacetic acid, were significantly higher in the diencephalon and telencephalon of the chicks in the hungry group. In conclusion, the changes in the free amino acids and monoamines in the brain may have some role in the feeding behavior of

  2. Isolated bilateral transverse agenesis of the distal segments of the lower limbs at the level of the knee joint in a human fetus.

    PubMed

    Christiaens, Antoine B; Deprez, Pierre M L; Amyere, Mustapha; Mendola, Antonella; Bernard, Pierre; Gillerot, Yves; Clapuyt, Philippe; Godfraind, Catherine; Lengelé, Benoît G; Vikkula, Miikka; Nyssen-Behets, Catherine

    2016-02-01

    Congenital limb anomalies occur in Europe with a prevalence of 3.81/1,000 births and can have a major impact on patients and their families. The present study concerned a female fetus aborted at 23 weeks of gestation because she was affected by non-syndromic bilateral absence of the zeugopod (leg) and autopod (foot). Autopsy of the aborted fetus, X-ray imaging, MRI, and histochemical analysis showed that the distal extremity of both femurs was continued by a cartilage-like mass, without joint cavitation. Karyotype was normal. Moreover, no damaging variant was detected by exome sequencing. The limb characteristics of the fetus, which to our knowledge have not yet been reported in humans, suggest a developmental arrest similar to anomalies described in chicks following surgical experiments on the apical ectodermal ridge of the lower limbs. PMID:26544544

  3. Sonic hedgehog-expressing cells in the developing limb measure time by an intrinsic cell cycle clock.

    PubMed

    Chinnaiya, Kavitha; Tickle, Cheryll; Towers, Matthew

    2014-01-01

    How time is measured is an enduring issue in developmental biology. Classical models of somitogenesis and limb development implicated intrinsic cell cycle clocks, but their existence remains controversial. Here we show that an intrinsic cell cycle clock in polarizing region cells of the chick limb bud times the duration of Sonic hedgehog (Shh) expression, which encodes the morphogen specifying digit pattern across the antero-posterior axis (thumb to little finger). Timing by this clock starts when polarizing region cells fall out of range of retinoic acid signalling. We found that timing of Shh transcription by the cell cycle clock can be reset, thus revealing an embryonic form of self-renewal. In contrast, antero-posterior positional values cannot be reset, suggesting that this may be an important constraint on digit regeneration. Our findings provide the first evidence for an intrinsic cell cycle timer controlling duration and patterning activity of a major embryonic signalling centre.

  4. Acetylcholinesterase Regulates Skeletal In Ovo Development of Chicken Limbs by ACh-Dependent and -Independent Mechanisms

    PubMed Central

    Spieker, Janine; Ackermann, Anica; Salfelder, Anika; Vogel-Höpker, Astrid; Layer, Paul G.

    2016-01-01

    Formation of the vertebrate limb presents an excellent model to analyze a non-neuronal cholinergic system (NNCS). Here, we first analyzed the expression of acetylcholinesterase (AChE) by IHC and of choline acetyltransferase (ChAT) by ISH in developing embryonic chicken limbs (stages HH17-37). AChE outlined formation of bones, being strongest at their distal tips, and later also marked areas of cell death. At onset, AChE and ChAT were elevated in two organizing centers of the limb anlage, the apical ectodermal ridge (AER) and zone of polarizing activity (ZPA), respectively. Thereby ChAT was expressed shortly after AChE, thus strongly supporting a leading role of AChE in limb formation. Then, we conducted loss-of-function studies via unilateral implantation of beads into chicken limb anlagen, which were soaked in cholinergic components. After varying periods, the formation of cartilage matrix and of mineralizing bones was followed by Alcian blue (AB) and Alizarin red (AR) stainings, respectively. Both acetylcholine (ACh)- and ChAT-soaked beads accelerated bone formation in ovo. Notably, inhibition of AChE by BW284c51, or by the monoclonal antibody MAB304 delayed cartilage formation. Since bead inhibition of BChE was mostly ineffective, an ACh-independent action during BW284c51 and MAB304 inhibition was indicated, which possibly could be due to an enzymatic side activity of AChE. In conclusion, skeletogenesis in chick is regulated by an ACh-dependent cholinergic system, but to some extent also by an ACh-independent aspect of the AChE protein. PMID:27574787

  5. Acetylcholinesterase Regulates Skeletal In Ovo Development of Chicken Limbs by ACh-Dependent and -Independent Mechanisms.

    PubMed

    Spieker, Janine; Ackermann, Anica; Salfelder, Anika; Vogel-Höpker, Astrid; Layer, Paul G

    2016-01-01

    Formation of the vertebrate limb presents an excellent model to analyze a non-neuronal cholinergic system (NNCS). Here, we first analyzed the expression of acetylcholinesterase (AChE) by IHC and of choline acetyltransferase (ChAT) by ISH in developing embryonic chicken limbs (stages HH17-37). AChE outlined formation of bones, being strongest at their distal tips, and later also marked areas of cell death. At onset, AChE and ChAT were elevated in two organizing centers of the limb anlage, the apical ectodermal ridge (AER) and zone of polarizing activity (ZPA), respectively. Thereby ChAT was expressed shortly after AChE, thus strongly supporting a leading role of AChE in limb formation. Then, we conducted loss-of-function studies via unilateral implantation of beads into chicken limb anlagen, which were soaked in cholinergic components. After varying periods, the formation of cartilage matrix and of mineralizing bones was followed by Alcian blue (AB) and Alizarin red (AR) stainings, respectively. Both acetylcholine (ACh)- and ChAT-soaked beads accelerated bone formation in ovo. Notably, inhibition of AChE by BW284c51, or by the monoclonal antibody MAB304 delayed cartilage formation. Since bead inhibition of BChE was mostly ineffective, an ACh-independent action during BW284c51 and MAB304 inhibition was indicated, which possibly could be due to an enzymatic side activity of AChE. In conclusion, skeletogenesis in chick is regulated by an ACh-dependent cholinergic system, but to some extent also by an ACh-independent aspect of the AChE protein. PMID:27574787

  6. Acute limb ischemia: contemporary approach.

    PubMed

    Fukuda, Ikuo; Chiyoya, Mari; Taniguchi, Satoshi; Fukuda, Wakako

    2015-10-01

    Acute limb ischemia is a critical condition with high mortality and morbidity even after surgical or endovascular intervention. Early recognition is important, but a delayed presentation is not uncommon. Viability of the limb is assessed by motor and sensory function and with interrogating Doppler flow signals in pedal arteries and popliteal veins as categorized by Rutherford. Category IIa indicates mild-to-moderate threat to limb salvage over a time frame without revascularization. Limb ischemia is critical without prompt revascularization in category IIb. Because the risk of reperfusion injury is high in this group of patients, perioperative management is important. In category III, reperfusion is not indicated except for embolism within several hours of onset. Intimal injury should be avoided by careful tactile control of a balloon with a smaller size catheter and under radiographic monitoring. Adjunctive treatment with catheter-directed thrombolysis or bypass surgery is sometimes necessary. Endovascular treatment is a promising option for thrombotic occlusion of an atherosclerotic artery. Ischemia-reperfusion injury is a serious problem. Controlled reperfusion with low-pressure perfusion at a reduced temperature and use of a leukocyte filter should be considered. The initial reperfusate is hyperosmolar, hypocalcemic, slightly alkaline, and contains free radical scavengers such as allopurinol. Immediate hemodialysis is necessary for acute renal injury caused by myoglobinemia. Compartment syndrome should be managed with assessment of intra-compartment pressure and fasciotomy.

  7. Anisotropic stress orients remodelling of mammalian limb bud ectoderm

    PubMed Central

    Lau, Kimberly; Tao, Hirotaka; Liu, Haijiao; Wen, Jun; Sturgeon, Kendra; Sorfazlian, Natalie; Lazic, Savo; Burrows, Jeffrey T. A.; Wong, Michael D.; Li, Danyi; Deimling, Steven; Ciruna, Brian; Scott, Ian; Simmons, Craig; Henkelman, R. Mark; Williams, Trevor; Hadjantonakis, Anna-Katerina; Fernandez-Gonzalez, Rodrigo; Sun, Yu; Hopyan, Sevan

    2016-01-01

    The physical forces that drive morphogenesis are not well characterized in vivo, especially among vertebrates. In the early limb bud, dorsal and ventral ectoderm converge to form the apical ectodermal ridge (AER), although the underlying mechanisms are unclear. By live imaging mouse embryos, we show that prospective AER progenitors intercalate at the dorsoventral boundary and that ectoderm remodels by concomitant cell division and neighbour exchange. Mesodermal expansion and ectodermal tension together generate a dorsoventrally biased stress pattern that orients ectodermal remodelling. Polarized distribution of cortical actin reflects this stress pattern in a β-catenin- and Fgfr2-dependent manner. Intercalation of AER progenitors generates a tensile gradient that reorients resolution of multicellular rosettes on adjacent surfaces, a process facilitated by β-catenin-dependent attachment of cortex to membrane. Therefore, feedback between tissue stress pattern and cell intercalations remodels mammalian ectoderm. PMID:25893915

  8. The mind through chick eyes: memory, cognition and anticipation.

    PubMed

    Matsushima, Toshiya; Izawa, Ei-Ichi; Aoki, Naoya; Yanagihara, Shin

    2003-04-01

    To understand the animal mind, we have to reconstruct how animals recognize the external world through their own eyes. For the reconstruction to be realistic, explanations must be made both in their proximate causes (brain mechanisms) as well as ultimate causes (evolutionary backgrounds). Here, we review recent advances in the behavioral, psychological, and system-neuroscience studies accomplished using the domestic chick as subjects. Diverse behavioral paradigms are compared (such as filial imprinting, sexual imprinting, one-trial passive avoidance learning, and reinforcement operant conditioning) in their behavioral characterizations (development, sensory and motor aspects of functions, fitness gains) and relevant brain mechanisms. We will stress that common brain regions are shared by these distinct paradigms, particularly those in the ventral telencephalic structures such as AIv (in the archistriatum) and LPO (in the medial striatum). Neuronal ensembles in these regions could code the chick's anticipation for forthcoming events, particularly the quality/quantity and the temporal proximity of rewards. Without the internal representation of the anticipated proximity in LPO, behavioral tolerance will be lost, and the chick makes impulsive choice for a less optimized option. Functional roles of these regions proved compatible with their anatomical counterparts in the mammalian brain, thus suggesting that the neural systems linking between the memorized past and the anticipated future have remained highly conservative through the evolution of the amniotic vertebrates during the last 300 million years. With the conservative nature in mind, research efforts should be oriented toward a unifying theory, which could explain behavioral deviations from optimized foraging, such as "naïve curiosity," "contra-freeloading," "Concorde fallacy," and "altruism."

  9. Avian embryos in hypoxic environments.

    PubMed

    León-Velarde, F; Monge-C, C

    2004-08-12

    Avian embryos at high altitude do not benefit of the maternal protection against hypoxia as in mammals. Nevertheless, avian embryos are known to hatch successfully at altitudes between 4,000 and 6,500 m. This review considers some of the processes that bring about the outstanding modifications in the pressure differences between the environment and mitochondria of avian embryos in hypoxic environments. Among species, some maintain normal levels of oxygen consumption ( VO2) have a high oxygen carrying capacity, lower the air cell-arterial pressure difference ( PAO2 - PaO2 ) with a constant pH. Other species decrease VO2, increase only slightly the oxygen carrying capacity, have a higher PAO2 - PaO2 difference than sea-level embryos and lower the PCO2 and pH. High altitude embryos, and those exposed to hypoxia have an accelerated decline of erythrocyte ATP levels during development and an earlier stimulation of 2,3-BPG synthesis. A higher Bohr effect may ensure high tissue PO2 in the presence of the high-affinity hemoglobin. Independently of the strategy used, they serve together to promote suitable rates of development and successful hatching of high altitude birds in hypoxic environments.

  10. Psychophysical correlates of phantom limb experience.

    PubMed Central

    Katz, J

    1992-01-01

    Phantom limb phenomena were correlated with psychophysiological measures of peripheral sympathetic nervous system activity measured at the amputation stump and contralateral limb. Amputees were assigned to one of three groups depending on whether they reported phantom limb pain, non-painful phantom limb sensations, or no phantom limb at all. Skin conductance and skin temperature were recorded continuously during two 30 minute sessions while subjects continuously monitored and rated the intensity of any phantom limb sensation or pain they experienced. The results from both sessions showed that mean skin temperature was significantly lower at the stump than the contralateral limb in the groups with phantom limb pain and non-painful phantom limb sensations, but not among subjects with no phantom limb at all. In addition, stump skin conductance responses correlated significantly with the intensity of non-painful phantom limb paresthesiae but not other qualities of sensation or pain. Between-limb measures of pressure sensitivity were not significantly different in any group. The results suggest that the presence of a phantom limb, whether painful or painless, is related to the sympathetic-efferent outflow of cutaneous vasoconstrictor fibres in the stump and stump neuromas. The hypothesis of a sympathetic-efferent somatic-afferent mechanism involving both sudomotor and vasoconstrictor fibres is proposed to explain the relationship between stump skin conductance responses and non-painful phantom limb paresthesiae. It is suggested that increases in the intensity of phantom limb paresthesiae follow bursts of sympathetic activity due to neurotransmitter release onto apposing sprouts of large diameter primary afferents located in stump neuromas, and decreases correspond to periods of relative sympathetic inactivity. The results of the study agree with recent suggestions that phantom limb pain is not a unitary syndrome, but a symptom class with each class subserved by

  11. Chicks' maze learning reinforced by visual pitfall extending downward.

    PubMed

    Hayashibe, K; Hara, M; Tsuji, K

    1989-04-01

    The present study examined whether visually evoked fear of depth could reinforce a particular response of animals, i.e., to special maze learning. The maze was composed of four units of Y-shaped alley. In this maze, the visual pitfalls were set behind corners of the alley in place of a physical barrier. The experiments showed that eight of 13 male chicks could achieve the initial learning and that three successful ones could also achieve reversal learning. The results suggest that the visually evoked fear of depth provided by motion parallax can act as a reinforcer.

  12. Feminists on the inalienability of human embryos.

    PubMed

    McLeod, Carolyn; Baylis, Francoise

    2006-01-01

    The feminist literature against the commodification of embryos in human embryo research includes an argument to the effect that embryos are "intimately connected" to persons, or morally inalienable from them. We explore why embryos might be inalienable to persons and why feminists might find this view appealing. But, ultimately, as feminists, we reject this view because it is inconsistent with full respect for women's reproductive autonomy and with a feminist conception of persons as relational, embodied beings. Overall, feminists should avoid claims about embryos' being inalienable to persons in arguments for or against the commodification of human embryos. PMID:17111554

  13. Gene expression and digit homology in the chicken embryo wing.

    PubMed

    Welten, Monique C M; Verbeek, Fons J; Meijer, Annemarie H; Richardson, Michael K

    2005-01-01

    The bird wing is of special interest to students of homology and avian evolution. Fossil and developmental data give conflicting indications of digit homology if a pentadactyl "archetype" is assumed. Morphological signs of a vestigial digit I are seen in bird embryos, but no digit-like structure develops in wild-type embryos. To examine the developmental mechanisms of digit loss, we studied the expression of the high-mobility group box containing Sox9 gene, and bone morphogenetic protein receptor 1b (bmpR-1b)-markers for precondensation and prechondrogenic cells, respectively. We find an elongated domain of Sox9 expression, but no bmpR-1b expression, anterior to digit II. We interpret this as a digit I domain that reaches precondensation, but not condensation or precartilage stages. It develops late, when the tissue in which it is lodged is being remodeled. We consider these findings in the light of previous Hoxd-11 misexpression studies. Together, they suggest that there is a digit I vestige in the wing that can be rescued and undergo development if posterior patterning cues are enhanced. We observed Sox9 expression in the elusive "element X" that is sometimes stated to represent a sixth digit. Indeed, incongruity between digit domains and identities in theropods disappears if birds and other archosaurs are considered primitively polydactyl. Our study provides the first gene expression evidence for at least five digital domains in the chick wing. The failure of the first to develop may be plausibly linked to attenuation of posterior signals.

  14. Evaluation of an experimental irradiated oocysts vaccine to protect broiler chicks against avian coccidosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The current study investigates the use of irradiated oocysts to protect broiler chicks, raised on litter, from infection with multiple species of Eimeria. In order to determine the optimum radiation dose for each Eimeria species, day- old chicks were immunized with oocysts of E. maxima, E. acervulin...

  15. Coots use hatch order to learn to recognize and reject conspecific brood parasitic chicks.

    PubMed

    Shizuka, Daizaburo; Lyon, Bruce E

    2010-01-14

    Avian brood parasites and their hosts provide model systems for investigating links between recognition, learning, and their fitness consequences. One major evolutionary puzzle has continued to capture the attention of naturalists for centuries: why do hosts of brood parasites generally fail to recognize parasitic offspring after they have hatched from the egg, even when the host and parasitic chicks differ to almost comic degrees? One prominent theory to explain this pattern proposes that the costs of mistakenly learning to recognize the wrong offspring make recognition maladaptive. Here we show that American coots, Fulica americana, can recognize and reject parasitic chicks in their brood by using learned cues, despite the fact that the hosts and the brood parasites are of the same species. A series of chick cross-fostering experiments confirm that coots use first-hatched chicks in a brood as referents to learn to recognize their own chicks and then discriminate against later-hatched parasitic chicks in the same brood. When experimentally provided with the wrong reference chicks, coots can be induced to discriminate against their own offspring, confirming that the learning errors proposed by theory can exist. However, learning based on hatching order is reliable in naturally parasitized coot nests because host eggs hatch predictably ahead of parasite eggs. Conversely, a lack of reliable information may help to explain why the evolution of chick recognition is not more common in hosts of most interspecific brood parasites. PMID:20016486

  16. Efficiency of several cultural methods and a chick bioassay to recover dry stressed Campylobacter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aims of the study were to evaluate the efficacy of 5 enrichment procedures for recovery of dry-atmospheric-temperature stressed C. jejuni and C. coli and determine the viable status of the non-culturable strains using a chick bioassay. Sterile chick paper pads (PP) and filter papers (FP) were i...

  17. In vivo functional imaging of blood flow and wall strain rate in outflow tract of embryonic chick heart using ultrafast spectral domain optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Li, Peng; Yin, Xin; Shi, Liang; Rugonyi, Sandra; Wang, Ruikang K.

    2012-09-01

    During cardiac development, the cardiac wall and flowing blood are two important cardiac tissues that constantly interact with each other. This dynamic interaction defines appropriate biomechanical environment to which the embryonic heart is exposed. Quantitative assessment of the dynamic parameters of wall tissues and blood flow is required to further our understanding of cardiac development. We report the use of an ultrafast 1310-nm dual-camera spectral domain optical coherence tomography (SDOCT) system to characterize/image, in parallel, the dynamic radial strain rate of the myocardial wall and the Doppler velocity of the underlying flowing blood within an in vivo beating chick embryo. The OCT system operates at 184-kHz line scan rate, providing the flexibility of imaging the fast blood flow and the slow tissue deformation within one scan. The ability to simultaneously characterize tissue motion and blood flow provides a useful approach to better understand cardiac dynamics during early developmental stages.

  18. From fins to limbs to fins: limb evolution in fossil marine reptiles.

    PubMed

    Caldwell, Michael W

    2002-10-15

    Limb osteology and ontogenetic patterns of limb ossification are reviewed for extinct lineages of aquatically adapted diapsid reptiles. Phylogenies including these fossil taxa show that paddle-like limbs were independently derived, and that the varied limb morphologies were produced by evolutionary modifications to different aspects of the limb skeleton. Ancient marine reptiles modify the limb by reducing the relative size of the epipodials, modifying the perichondral and periosteal surface of elements distal to the propodials, and evolving extremes of hyperphalangy and hyperdactyly. Developmental genetic models illuminate gene systems that may have controlled limb evolution in these animals. PMID:12357467

  19. Rotationally acquired four-dimensional optical coherence tomography of embryonic chick hearts using retrospective gating on the common central A-scan

    NASA Astrophysics Data System (ADS)

    Happel, Christoph M.; Thommes, Jan; Thrane, Lars; Männer, Jörg; Ortmaier, Tobias; Heimann,