DOCSLIB.ORG

Both Apoptosis and Necrosis (Development/Immunofluorescence) PIERRE-ALAIN FERNANDEZ*T, Rocco J

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Both Apoptosis and Necrosis (Development/Immunofluorescence) PIERRE-ALAIN FERNANDEZ*T, Rocco J Proc. Nadl. Acad. Sci. USA Vol. 91, pp. 8641-8645, August 1994 Cell Biology Expression of a specific marker of avian programmed cell death in both apoptosis and necrosis (development/immunofluorescence) PIERRE-ALAIN FERNANDEZ*t, Rocco J. ROTELLO*t, ZEHAVA RANGINI*t, ALLISON DOUPEt, HANNES C. A. DREXLER*t, AND JUNYING YUAN*t§ *Cardiovascular Research Center, Massachusetts General Hospital, 149 Thirteenth Street, Charlestown, MA 02129; tDepartment of Medicine, Harvard Medical School, Boston, MA 02115; and tDivision of Biology, California Institute of Technology, Pasadena, CA 91125 Communicated by H. Robert Horvitz, May 18, 1994 (receivedfor review December 3, 1993) ABSTRACT Apoptosis and necrosis are two types of cell 8-week-old F1 BALB/cJ x C57/BL male mice (The Jackson death with different morphologic features. We report here the Laboratory) primed with incomplete Freund's adjuvant (Cap- isolation of a monoclonal antibody, BV2, that specifically rec- pel), and 2 weeks later, ascites fluid was collected and purified ognize cells undergoing developmental programmed cell death by E-Z-Sep (Middlesex Sciences, Foxborough, MA). in different tissues ofthe chicken and zebra-finch embryos. The Immunofluorescence. Whole embryos and limbs were antigen recognized by BV2 monolonal antibody is detected in rinsed in cold phosphate-buffered saline (PBS) and fixed in vitro in primary chicken embryonic fibroblasts induced to die by 4% periodate/lysine/paraformaldehyde prepared in PBS for actinomycin D, as well as fibroblasts induced to die by chemical 12 hr at 4TC. Tissues were then washed in cold PBS and anoxia. The expression of this specific antigen during necrosis dehydrated in graded concentrations ofethanol (50%-95%) at appears to require active protein synthesis. These dinps 4TC. Infiltration was conducted with solution A ofJB-4 glycol provide evidence that cells from different embryonic tissues methacrylate embedding kit (Polyscience) in a light-protected undergoing prgrammed cell death during vertebrate develop- glass vial at 40C for several days (11). Tissues were embedded ment express simlr antigens and indicate that apoptosis and in glycol methacrylate and placed under vacuum (15 mmHg; necrosis may share similar biochemical features. 1 mmHg = 133 Pa) at 4°C and allowed to polymerize for 48 hr at 4°C (12). Sections were cut at 5 ,urm with glass knives on The morphological concept of apoptosis, defined as a phys- a Sorvall JB-4 microtome (DuPont), transferred via water to been as Superfrost/plus pretreated slides (Fisher Scientific), and iological type of cell death, has progressively used a air-dried at room temperature. For immunofluorescence synonym with the term programmed cell death, originally staining, the sections were treated with xylene for 30 min at described during normal development (1) and implying the room temperature, extensively washed with cold PBS, and existence of a genetic program of cell death (2). Apoptosis is digested with Pronase at 0.5 mg/ml (Sigma)/PBS for 1 hr at believed to account for most cell death during development 3rC. The enzyme reaction was stopped with cold 0.5 M Tris and in normal adult tissue turnover, and it can also be induced buffer on ice followed by washing in cold PBS. The slides experimentally by various biological, chemical, or physical were then treated with a blocking solution consisting of 1% agents (3). Necrosis, in contrast, has been defined as a bovine serum albumin (Sigma) and 1% heat-inactivated nor- passive degenerative phenomenon and is observed in a tissue mal goat serum (GIBCO) in PBS for 30 min at room temper- subjected to direct toxic or physical injury-such as hyper- ature. Incubation was conducted for 5 hr at room temperature thermia, hypoxia, and ischemia or to complement-mediated with the BV2 ascites fluid diluted in blocking buffer. After lysis (4-7). To investigate the mechanism of cell death, we several washes with PBS, affinity-purified goat anti-mouse have identified a monoclonal antibody (mAb), BV2, that antibody conjugated with fluorescein (1:100, Cappel) was specifically recognizes cells undergoing programmed cell diluted into blocking buffer and applied to the slides for 1 hr death in developing chicken embryos, and we used BV2 mAb at room temperature together with Hoechst 33258 (Ho 33258) as a specific marker of chicken programmed cell death to dye (0.5 jug/ml, Sigma), a DNA minor groove-binding ligand study the relationship between apoptosis and necrosis. that has strong adenine plus thymidine sequence specificity (13). After washing with PBS, the slides were mounted in 10o MATERIALS AND METHODS PBS/90% glycerol with p-phenylenediamine at 1 mg/ml (Sigma) to prevent photo bleaching. To verify the specificity Generation of mAbs. Chicken eggs were purchased from of the antibody labeling, control staining was done with Spafas, Norwich, CT. Zebra finches (Poephila guttata) were preimmune or nonimmune immunoglobulins as primary an- grown in the avian facilities of the California Institute of tibodies or with secondary antibody alone. No significant Technology. Chicken embryos were staged according to V. staining was obtained with these controls, even in compact Hamburger and H. L. Hamilton (8). The generation of the tissues. Positive controls included several antibodies specific cell-death-specific mAbs by neonatal tolerization (9) is de- for different chicken structures. Serial sections were coun- scribed in detail elsewhere (10). BV2 hybridoma was screened terstained by methylene blue-azure II and basic fuchsin (14). on sections of day 7 chicken hind limb foot plates, expanded, Sections were examined with a Zeiss epifluorescence Axio- and assayed several times for antibody reactivity and stabi- plan microscope with x20, x40, and xlO0 objectives and a lized by three cycles of cloning by limiting dilution. The filter set and photographed by using Kodak 1600 ASA film. immunoglobulin (IgM) type was determined by ELISA using Cell Cultures. Primary chicken embryo fibroblast cultures rat mAb anti-mouse immunoglobulin classes from Amersham. were freshly prepared for every experiment from 9-day-old BV2 hybridoma cells (2-5 x 106) were injected into 7- to embryos (15). Cells were plated out at different densities on culture slides with four chambers (Nunc) coated with type 1 The publication costs ofthis article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" Abbreviation: mAb, monoclonal antibody. in accordance with 18 U.S.C. §1734 solely to indicate this fact. §To whom reprint requests should be addressed. 8641 Downloaded by guest on September 28, 2021 8642 Cell Biology: Fernandez et al. Proc. Natl. Acad Sci. USA 91 (1994) collagen (Sigma, 500 Al of a 50 ,ug/ml solution for 8 hr) and adhering cells were harvested by trypsinization and com- were cultured in F-12 medium (GIBCO)/10% fetal bovine bined with floating cells present in the supernatant. After serum (HyClone)/2.5% chicken serum (Sigma), penicillin at centrifugation, the cell pellet was lysed in extraction buffer 100 units/ml (GIBCO)/streptomycin at 100 ,ug/ml (GIBCO) (100 mM NaCl/25 mM EDTA/10 mM Tris HCl, pH 8.0/0.5% at 370C in an atmosphere of 5% C02/95% air in a humidified SDS/proteinase K at 100 pg/ml for 3 hr at 55°C, extracted incubator. To mimic a state of cell anoxia, 1 mM KCN and twice with phenol/chloroform and once with chloroform; the 2 mM iodoacetate were added to the culture medium. Cell DNA was then ethanol-precipitated overnight at -80°C. The death was also induced with 10-6 M actinomycin D, and precipitated DNA was dissolved in 10 mM Tris, pH 8/1 mM inhibition of protein synthesis was done with cycloheximide EDTA containing RNase A at 10 pg/ml and analyzed on a at 50 Ag/mI (all chemicals from Sigma). Loss of cell viability 1.7% agarose gel. Electrophoresis was done for 3 hr at 140 V, was determined by failure to exclude Trypan blue and by and the DNA was visualized by staining with ethidium measuring the leakage of L-lactate dehydrogenase (EC bromide. DNA from untreated chicken embryonic fibroblasts 1.1.1.27) by Sigma procedure no. 500. For antibody staining, was extracted in parallel and served as a control. cell cultures were rinsed in cold PBS, fixed in freshly prepared 4% periodate/lysine/paraformaldehyde in PBS for 15 min at room temperature, and then rinsed twice in cold RESULTS PBS for 5 min. Cells were permeabilized by treatment with Isolation of the mAb. The mAb BV2 was isolated, after 0.2% Triton X-100 in PBS at room temperature for 2 min (to neonatal tolerization, by immunization of mice with embry- preserve the cytoskeleton structure) to allow penetration of onic day 7 (stage 31) chicken foot plates. At this stage, antibodies into the cells and eliminate the danger of further developmental programmed cell death is easily identifiable in osmotic damage. Cell culture slides were then rinsed with the interdigital mesenchymal areas of foot plates (Fig. 1A). PBS, and immunofluorescence staining was done as de- Interdigital programmed cell death, a major process during scribed. Actin filaments were stained with tetramethyl- the morphogenesis of digits in all nonwebbed amniotes, rhodamine B isothiocyanate-phalloidin (10-7 M, Sigma). including the human, plays an important role in the separa- Rhodamine-conjugated wheat germ agglutinin (10 jug/ml, tion ofthe chondrifying digits (17, 18). To selectively enhance Sigma) was used as a marker for the Golgi apparatus because the production of antibodies specific for dying cells, the of its high affinity for the terminal glucosamine residues mouse immune response to living-cell antigens was sup- present in incompletely glycosylated proteins (16). pressed by injecting newborn mice with day 10 chicken foot DNA Fragmentation Assay. After treating primary chicken plate tissues (with virtually no cell death) before immuniza- embryonic fibroblasts for 24 hr (1 x 107 cells per 10-cm dish) tion.
Load more

Recommended publications
  • Segmentation and Specification of the Drosophila Mesoderm
    Downloaded from genesdev.cshlp.org on September 25, 2021 - Published by Cold Spring Harbor Laboratory Press Segmentation and specification of the Drosophila mesoderm Natalia Azpiazu, 1,3 Peter A. Lawrence, 2 Jean-Paul Vincent, 2 and Manfred Frasch 1'4 1Brookdale Center for Molecular Biology, Mount Sinai School of Medicine, New York, New York 10029 USA; 2Medical Research Council Laboratory of Molecular Biology, Cambridge CB2 2QH, UK Patterning of the developing mesoderm establishes primordia of the visceral, somatic, and cardiac tissues at defined anteroposterior and dorsoventral positions in each segment. Here we examine the mechanisms that locate and determine these primordia. We focus on the regulation of two mesodermal genes: bagpipe (hap), which defines the anlagen of the visceral musculature of the midgut, and serpent (srp), which marks the anlagen of the fat body. These two genes are activated in specific groups of mesodermal cells in the anterior portions of each parasegment. Other genes mark the anlagen of the cardiac and somatic mesoderm and these are expressed mainly in cells derived from posterior portions of each parasegment. Thus the parasegments appear to be subdivided, at least with respect to these genes, a subdivision that depends on pair-rule genes such as even-skipped (eve). We show with genetic mosaics that eve acts autonomously within the mesoderm. We also show that hedgehog (hh) and wingless (wg) mediate pair-rule gene functions in the mesoderm, probably partly by acting within the mesoderm and partly by inductive signaling from the ectoderm, hh is required for the normal activation of hap and srp in anterior portions of each parasegment, whereas wg is required to suppress bap and srp expression in posterior portions.
    [Show full text]
  • Mesoderm Induction and the Control of Gastrulation in Xenopus Laevis:The
    Development 108, 229-238 (1990) 229 Printed in Great Britain ©The Company of Biologists Limited 1990 Mesoderm induction and the control of gastrulation in Xenopus laevis: the roles of fibronectin and integrins J. C. SMITH1, K. SYMESH, R. O. HYNES2'3 and D. DeSIMONE3* ' Laboratory of Embryogenesis, National Institute for Medical Research, The Ridgeway, Mill Hill, London NW71AA, UK ^Howard Hughes Medical Institute and ^Center for Cancer Research, Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA * Present address: University of Virginia, Health Sciences Center, Department of Anatomy and Cell Biology, Box 439, School of Medicine, Charlottesville, VA 22908, USA t Present address: Department of Cell and Molecular Biology, 385 LSA, University of California, Berkeley, CA 94720, USA Summary Exposure of isolated Xenopus animal pole ectoderm to diated cell migration is not required for convergent the XTC mesoderm-inducing factor (XTC-MIF) causes extension. the tissue to undergo gastrulation-like movements. In We have investigated the molecular basis of XTC- this paper, we take advantage of this observation to MIF-induced gastrulation-like movements by measuring investigate the control of various aspects of gastrulation rates of synthesis of fibronectin and of the integrin f}y in Xenopus. chain in induced and control explants. No significant Blastomcres derived from induced animal pole regions differences were observed, and this suggests that gastru- are able, like marginal zone cells, but unlike control lation is not initiated simply by control of synthesis of animal pole blastomeres, to spread and migrate on a these molecules. In future work, we intend to investigate fibronectin-coated surface.
    [Show full text]
  • Understanding Paraxial Mesoderm Development and Sclerotome Specification for Skeletal Repair Shoichiro Tani 1,2, Ung-Il Chung2,3, Shinsuke Ohba4 and Hironori Hojo2,3
    Tani et al. Experimental & Molecular Medicine (2020) 52:1166–1177 https://doi.org/10.1038/s12276-020-0482-1 Experimental & Molecular Medicine REVIEW ARTICLE Open Access Understanding paraxial mesoderm development and sclerotome specification for skeletal repair Shoichiro Tani 1,2, Ung-il Chung2,3, Shinsuke Ohba4 and Hironori Hojo2,3 Abstract Pluripotent stem cells (PSCs) are attractive regenerative therapy tools for skeletal tissues. However, a deep understanding of skeletal development is required in order to model this development with PSCs, and for the application of PSCs in clinical settings. Skeletal tissues originate from three types of cell populations: the paraxial mesoderm, lateral plate mesoderm, and neural crest. The paraxial mesoderm gives rise to the sclerotome mainly through somitogenesis. In this process, key developmental processes, including initiation of the segmentation clock, formation of the determination front, and the mesenchymal–epithelial transition, are sequentially coordinated. The sclerotome further forms vertebral columns and contributes to various other tissues, such as tendons, vessels (including the dorsal aorta), and even meninges. To understand the molecular mechanisms underlying these developmental processes, extensive studies have been conducted. These studies have demonstrated that a gradient of activities involving multiple signaling pathways specify the embryonic axis and induce cell-type-specific master transcription factors in a spatiotemporal manner. Moreover, applying the knowledge of mesoderm development, researchers have attempted to recapitulate the in vivo development processes in in vitro settings, using mouse and human PSCs. In this review, we summarize the state-of-the-art understanding of mesoderm development and in vitro modeling of mesoderm development using PSCs. We also discuss future perspectives on the use of PSCs to generate skeletal tissues for basic research and clinical applications.
    [Show full text]
  • Sonic Hedgehog a Neural Tube Anti-Apoptotic Factor 4013 Other Side of the Neural Plate, Remaining in Contact with Midline Cells, RESULTS Was Used As a Control
    Development 128, 4011-4020 (2001) 4011 Printed in Great Britain © The Company of Biologists Limited 2001 DEV2740 Anti-apoptotic role of Sonic hedgehog protein at the early stages of nervous system organogenesis Jean-Baptiste Charrier, Françoise Lapointe, Nicole M. Le Douarin and Marie-Aimée Teillet* Institut d’Embryologie Cellulaire et Moléculaire, CNRS FRE2160, 49bis Avenue de la Belle Gabrielle, 94736 Nogent-sur-Marne Cedex, France *Author for correspondence (e-mail: [email protected]) Accepted 19 July 2001 SUMMARY In vertebrates the neural tube, like most of the embryonic notochord or a floor plate fragment in its vicinity. The organs, shows discreet areas of programmed cell death at neural tube can also be recovered by transplanting it into several stages during development. In the chick embryo, a stage-matched chick embryo having one of these cell death is dramatically increased in the developing structures. In addition, cells engineered to produce Sonic nervous system and other tissues when the midline cells, hedgehog protein (SHH) can mimic the effect of the notochord and floor plate, are prevented from forming by notochord and floor plate cells in in situ grafts and excision of the axial-paraxial hinge (APH), i.e. caudal transplantation experiments. SHH can thus counteract a Hensen’s node and rostral primitive streak, at the 6-somite built-in cell death program and thereby contribute to organ stage (Charrier, J. B., Teillet, M.-A., Lapointe, F. and Le morphogenesis, in particular in the central nervous system. Douarin, N. M. (1999). Development 126, 4771-4783). In this paper we demonstrate that one day after APH excision, Key words: Apoptosis, Avian embryo, Cell death, Cell survival, when dramatic apoptosis is already present in the neural Floor plate, Notochord, Quail/chick, Shh, Somite, Neural tube, tube, the latter can be rescued from death by grafting a Spinal cord INTRODUCTION generally induces an inflammatory response.
    [Show full text]
  • The Derivatives of Three-Layered Embryo (Germ Layers)
    HUMANHUMAN EMBRYOLOGYEMBRYOLOGY Department of Histology and Embryology Jilin University ChapterChapter 22 GeneralGeneral EmbryologyEmbryology FourthFourth week:week: TheThe derivativesderivatives ofof trilaminartrilaminar germgerm discdisc Dorsal side of the germ disc. At the beginning of the third week of development, the ectodermal germ layer has the shape of a disc that is broader in the cephalic than the caudal region. Cross section shows formation of trilaminar germ disc Primitive pit Drawing of a sagittal section through a 17-day embryo. The most cranial portion of the definitive notochord has formed. ectoderm Schematic view showing the definitive notochord. horizon =ectoderm hillside fields =neural plate mountain peaks =neural folds Cave sinks into mountain =neural tube valley =neural groove 7.1 Derivatives of the Ectodermal Germ Layer 1) Formation of neural tube Notochord induces the overlying ectoderm to thicken and form the neural plate. Cross section Animation of formation of neural plate When notochord is forming, primitive streak is shorten. At meanwhile, neural plate is induced to form cephalic to caudal end, following formation of notochord. By the end of 3rd week, neural folds and neural groove are formed. Neural folds fuse in the midline, beginning in cervical region and Cross section proceeding cranially and caudally. Neural tube is formed & invade into the embryo body. A. Dorsal view of a human embryo at approximately day 22. B. Dorsal view of a human embryo at approximately day 23. The nervous system is in connection with the amniotic cavity through the cranial and caudal neuropores. Cranial/anterior neuropore Neural fold heart Neural groove endoderm caudal/posterior neuropore A.
    [Show full text]
  • Differential Genetic Mutations of Ectoderm, Mesoderm, And
    Gao et al. Cancer Cell Int (2020) 20:595 https://doi.org/10.1186/s12935-020-01678-x Cancer Cell International PRIMARY RESEARCH Open Access Diferential genetic mutations of ectoderm, mesoderm, and endoderm-derived tumors in TCGA database Xingjie Gao1,2*, Xiaoteng Cui1,2,3, Xinxin Zhang1,2, Chunyan Zhao1,2, Nan Zhang1,2, Yan Zhao1,2, Yuanyuan Ren1,2, Chao Su1,2, Lin Ge1,2, Shaoyuan Wu1,2 and Jie Yang1,2* Abstract Background: In terms of biological behavior, gene regulation, or signaling pathways, there is a certain similarity between tumorigenesis and embryonic development of humans. Three germ layer structure exhibits the distinct abil- ity to form specifc tissues and organs. Methods: The present study set out to investigate the genetic mutation characteristics of germ layer diferentiation- related genes using the tumor cases of the cancer genome atlas (TCGA) database. Results: These tumor samples were divided into three groups, including the ectoderm, mesoderm, and endoderm. Children cases less than 9 years old accounted for a larger proportion for the cases in the ectoderm and mesoderm groups; whereas the middle-aged and elderly individuals (from 50 to 89 years old) were more susceptible to tumors of endoderm. There was a better prognosis for the cases of mesoderm, especially the male with the race of White, compared with the other groups. A missense mutation was frequently detected for the cases of ectoderm and endo- derm, while deletion mutation was common for that of mesoderm. We could not identify the ectoderm, mesoderm, or endoderm-specifc mutated genes or variants with high mutation frequency.
    [Show full text]
  • Programmed Cell Death in the Developing Limb
    Int. J. Dev. Biol. 46: 871-876 (2002) Programmed cell death in the developing limb VANESSA ZUZARTE-LUÍS and JUAN M. HURLÉ* Departamento de Anatomía y Biología Celular, Facultad de Medicina, Universidad de Cantabria, Santander, Spain ABSTRACT The sculpturing of shape in the developing limb together with the regression of the tail in anuran tadpoles constitute, perhaps, the most paradigmatic processes of programmed cell death. The study of these model systems has been of fundamental importance to support the idea that cell death is a physiological behavior of cells in multicellular organisms. Furthermore, different experimental approaches, including comparative analyses of the pattern of cell death in different avian species (i.e. chick interdigits versus duck interdigital webs) and in chick mutants with different limb phenotypes, provided the first evidence for the occurrence of a genetic program underlying the control of cell death. Two well known research groups in the field of limb development, the USA group headed first by John Saunders and next by John Fallon and the group of Donald Ede and Richard Hinchliffe in the U.K. provided a remarkable contribution to this topic. In spite of the historical importance of the developing limb in establishing the concept of programmed cell death, this model system of tissue regression has been largely neglected in recent studies devoted to the analysis of the molecular control of self-induced cell death (apoptosis). However, a considerable amount of information concerning this topic has been obtained in the last few years. Here we will review current information on the control of limb programmed cell death in an attempt to stimulate further molecular studies of this process of tissue regression.
    [Show full text]
  • Functional Morphology of the Cardiac Jelly in the Tubular Heart of Vertebrate Embryos
    Review Functional Morphology of the Cardiac Jelly in the Tubular Heart of Vertebrate Embryos Jörg Männer 1,*,† and Talat Mesud Yelbuz 2,† 1 Group Cardio‐Embryology, Institute of Anatomy and Embryology UMG, Georg‐August‐University Goettingen, D‐37075 Goettingen, Germany; [email protected] 2 Department of Cardiac Sciences, King Abdulaziz Cardiac Center, Section of Pediatric Cardiology, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh 11426, Saudi Arabia; [email protected] * Correspondence: [email protected]; Tel.: +49‐551‐39‐7032 † This work is dedicated to the memory of our academic mentors Gerd Steding (1936–2011) and Armin Wessel (1946–2011). Received: 29 January 2019; Accepted: 21 February 2019; Published: 27 February 2019 Abstract: The early embryonic heart is a multi‐layered tube consisting of (1) an outer myocardial tube; (2) an inner endocardial tube; and (3) an extracellular matrix layer interposed between the myocardium and endocardium, called “cardiac jelly” (CJ). During the past decades, research on CJ has mainly focused on its molecular and cellular biological aspects. This review focuses on the morphological and biomechanical aspects of CJ. Special attention is given to (1) the spatial distribution and fiber architecture of CJ; (2) the morphological dynamics of CJ during the cardiac cycle; and (3) the removal/remodeling of CJ during advanced heart looping stages, which leads to the formation of ventricular trabeculations and endocardial cushions. CJ acts as a hydraulic skeleton, displaying striking structural and functional similarities with the mesoglea of jellyfish. CJ not only represents a filler substance, facilitating end‐systolic occlusion of the embryonic heart lumen.
    [Show full text]
  • Conversion of Presumptive Ectoderm to Mesoderm in the Chick by C
    335 CONVERSION OF PRESUMPTIVE ECTODERM TO MESODERM IN THE CHICK BY C. H. WADDINGTON,1 M.A. AND JEAN TAYLOR, B.A. From the Strangeways Laboratory and Sub-Department of Experimental Zoology, Cambridge (Received 10 November 1936) (With One Plate) INTRODUCTION THE greater part of descriptive embryology is based on the concept of the three germ-layers—ectoderm, mesoderm and endoderm. As we acquire more information about the physiology of development, it is natural to ask whether the same concept is as fundamental for a consideration of individual development as it is for com- parative morphology. The investigations on the Amphibia have already provided a negative answer for that group. Mangold (1925), in a review on the subject, pointed out that presumptive ectoderm could be caused to undergo differentiation into endodermal organs or mesodermal organs. More recently, Lopashov (1935) and Tondury (1936) have shown that mesoderm can become ectoderm. Only the heavy yolk-laden endoderm cannot be changed into anything else, a disability which is probably not an expression of any fundamental determination but rather an adventitious circumstance depending on the presence of large masses of inactive yolk. Mangold describes two ways in which ectoderm can-become converted into mesoderm; either the presumptive ectoderm can be grafted into the blastopore or it can be inserted directly into the blastocoel cavity. In the first case, it takes part in the gastrulation movements of the host, but the fact that mesodermal organs are also formed by grafts made in the second way show that these movements are not essential for subsequent mesodermal differentiation.
    [Show full text]
  • Embryology and Teratology in the Curricula of Healthcare Courses
    ANATOMICAL EDUCATION Eur. J. Anat. 21 (1): 77-91 (2017) Embryology and Teratology in the Curricula of Healthcare Courses Bernard J. Moxham 1, Hana Brichova 2, Elpida Emmanouil-Nikoloussi 3, Andy R.M. Chirculescu 4 1Cardiff School of Biosciences, Cardiff University, Museum Avenue, Cardiff CF10 3AX, Wales, United Kingdom and Department of Anatomy, St. George’s University, St George, Grenada, 2First Faculty of Medicine, Institute of Histology and Embryology, Charles University Prague, Albertov 4, 128 01 Prague 2, Czech Republic and Second Medical Facul- ty, Institute of Histology and Embryology, Charles University Prague, V Úvalu 84, 150 00 Prague 5 , Czech Republic, 3The School of Medicine, European University Cyprus, 6 Diogenous str, 2404 Engomi, P.O.Box 22006, 1516 Nicosia, Cyprus , 4Department of Morphological Sciences, Division of Anatomy, Faculty of Medicine, C. Davila University, Bucharest, Romania SUMMARY Key words: Anatomy – Embryology – Education – Syllabus – Medical – Dental – Healthcare Significant changes are occurring worldwide in courses for healthcare studies, including medicine INTRODUCTION and dentistry. Critical evaluation of the place, tim- ing, and content of components that can be collec- Embryology is a sub-discipline of developmental tively grouped as the anatomical sciences has biology that relates to life before birth. Teratology however yet to be adequately undertaken. Surveys (τέρατος (teratos) meaning ‘monster’ or ‘marvel’) of teaching hours for embryology in US and UK relates to abnormal development and congenital medical courses clearly demonstrate that a dra- abnormalities (i.e. morphofunctional impairments). matic decline in the importance of the subject is in Embryological studies are concerned essentially progress, in terms of both a decrease in the num- with the laws and mechanisms associated with ber of hours allocated within the medical course normal development (ontogenesis) from the stage and in relation to changes in pedagogic methodol- of the ovum until parturition and the end of intra- ogies.
    [Show full text]
  • Programmed Cell Death in the Developing Somites Is Promoted By
    Developmental Biology 228, 326–336 (2000) doi:10.1006/dbio.2000.9948, available online at http://www.idealibrary.com on View metadata, citation and similar papers at core.ac.uk brought to you by CORE Programmed Cell Death in the Developing Somitesprovided by Elsevier - Publisher Connector Is Promoted by Nerve Growth Factor via Its p75NTR Receptor Marı´a L. Cotrina, Maritza Gonza´lez-Hoyuela, Julio A. Barbas, and Alfredo Rodrı´guez-Te´bar1 Instituto Cajal de Neurobiologı´a, CSIC, Avenida Doctor Arce, 37, E-28002 Madrid, Spain Neurotrophins control neuron number during development by promoting the generation and survival of neurons and by regulating programmed neuronal death. In the latter case, the cell death induced by nerve growth factor (NGF) in the developing chick retina is mediated by p75NTR, the common neurotrophin receptor (J. M. Frade, A. Rodriguez-Tebar, and Y.-A. Barde, 1996, Nature 383, 166–168). Here we show that NGF also induces the programmed death of paraxial mesoderm cells in the developing somites. Both NGF and p75NTR are expressed in the somites of chick embryos at the time and the place of programmed cell death. Moreover, neutralizing the activity of endogenous NGF with a specific blocking antibody, or antagonizing NGF binding to p75NTR by the application of human NT-4/5, reduces the levels of apoptotic cell death in both the sclerotome and the dermamyotome by about 50 and 70%, respectively. Previous data have shown that Sonic hedgehog is necessary for the survival of differentiated somite cells. Consistent with this, Sonic hedgehog induces a decrease of NGF mRNA in somite explant cultures, thus showing the antagonistic effect of NGF and Sonic hedgehog with respect to somite cell survival.
    [Show full text]
  • Functional Morphology of the Cardiac Jelly in the Tubular
    Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 30 January 2019 doi:10.20944/preprints201901.0312.v1 Peer-reviewed version available at J. Cardiovasc. Dev. Dis. 2019, 6, 12; doi:10.3390/jcdd6010012 1 Review 2 Functional Morphology of the Cardiac Jelly in the 3 Tubular Heart of Vertebrate Embryos 4 Jörg Männer 1,* and Talat Mesud Yelbuz 2 5 1 Group Cardio-Embryology, Institute of Anatomy and Embryology UMG, Georg-August-University 6 Goettingen, D-37075 Goettingen, Germany; [email protected] 7 2 Department of Cardiac Sciences, King Abdulaziz Cardiac Center, Section of Pediatric Cardiology, King 8 Abdulaziz Medical City, Ministry of National Guard Health Affairs; Riyadh, Kingdom of Saudi Arabia; 9 [email protected] 10 * Correspondence: [email protected]; Tel.: +49-551-39-7032 11 12 Abstract: The early embryonic heart is a multi-layered tube consisting of (1) an 13 outer myocardial tube; (2) an inner endocardial tube; and (3) an extracellular 14 matrix layer interposed between myocardium and endocardium, called “cardiac 15 jelly” (CJ). During the past decades, research on CJ has mainly focused on its 16 molecular and cell biological aspects. This review focuses on the morphological 17 and biomechanical aspects of CJ. Special attention is given to (1) the spatial 18 distribution and fiber architecture of CJ; (2) the morphological dynamics of CJ 19 during the cardiac cycle; and (3) the removal/remodeling of CJ during advanced 20 heart looping stages, which leads to the formation of ventricular trabeculations 21 and endocardial cushions. CJ acts as a hydraulic skeleton displaying striking 22 structural and functional similarities with the mesoglea of jellyfish.
    [Show full text]