early embryological development: Topics by Science.gov

Sample records for early embryological development

Mammalian and avian embryology at Warsaw University (Poland) from XIX century to the present.

PubMed

Tarkowski, Andrzej K; Maleszewski, Marek; Rogulska, Teresa; Ciemerych, Maria A; Borsuk, Ewa

2008-01-01

In this article, we describe the history (between the XIX century and World War II) of embryological research conducted at Warsaw University, together with current research activities being carried out at the Department of Embryology. During the partition of Poland, the Imperial (Russian) Warsaw University conducted research on avian embryology (and to a smaller extent, on reptilian embryology). When Poland regained independence in 1918, these studies were continued under the Chair of Comparative Anatomy headed by Professor Jan Tur. A new Department of Embryology created in 1954 was first headed by Professor Stanislaw Bilewicz and since 1964 by Professor Andrzej Tarkowski, who in 2003 was succeeded by Dr. Marek Maleszewski D.Sc. During the last 45 years, embryological research at Warsaw University has concentrated mainly on mammalian development with special emphasis on the regulative capabilities of early embryos and also on experimental chimaeras, nucleo-cytoplasmic interactions in oogenesis and early embryogenesis (including regulation of DNA replication and transcription), experimental parthenogenesis and fertilization.
The attitudes of medical students in Europe toward the clinical importance of embryology.

PubMed

Moxham, Bernard John; Emmanouil-Nikoloussi, Elpida; Standley, Henrietta; Brenner, Erich; Plaisant, Odile; Brichova, Hana; Pais, Diogo; Stabile, Isobel; Borg, Jordy; Chirculescu, Andy

2016-03-01

Although there have been many studies reporting the attitudes of medical students to the clinical importance of gross anatomy, little is known about their opinions concerning the clinical importance of embryology. Using Thurstone and Chave methods to assess attitudes, nearly 1,600 medical students across Europe in the early stages of their training provided responses to a survey that tested the hypothesis that they do not regard embryology as highly clinically relevant. Indeed, we further proposed that student attitudes to gross anatomy are much more positive than those toward embryology. Our findings show that our hypotheses hold, regardless of the university and country surveyed and regardless of the teaching methods employed for embryology. Clearly, embryology has a significant part to play in medical education in terms of understanding prenatal life, of appreciating how the organization of the mature human body has developed, and of providing essential information for general medical practice, obstetrics and pediatrics, and teratology. However, while newly recruited medical students understand the importance of gross anatomy in the development of professional competence, understanding the importance of embryology requires teachers, medical educationalists, and devisors of medical curricula to pay special attention to informing students of the significant role played by embryology in attaining clinical competence and achieving the knowledge and understanding of the biomedical sciences that underpins becoming a learned member of a health care profession. © 2015 Wiley Periodicals, Inc.
Early reproductive developmental anatomy in Decaisnea (Lardizabalaceae) and its systematic implications.

PubMed

Wang, Hua-Feng; Friedman, Cynthia Ross; Zhu, Zhi-Xin; Qin, Hai-Ning

2009-11-01

Decaisnea insignis, known as 'dead man's fingers' (Lardizabalaceae), is widely distributed in China and the Himalayan foothill countries. This economically important plant, which is the only species in the genus, has not been the subject of any embryological studies aside from one brief, older paper that lacks micrographs. Data on Decaisnea are also important because its systematic position has been unstable since the genus was established in 1855. Therefore, the objectives of this study were: (a) to use modern microscopy to document early reproductive anatomical development in Decaisnea; and (b) to compare qualitatively these early embryological characters with allied taxa in a systematic context. Decaisnea insignis floral buds and inflorescences were regularly collected from Shaanxi Province, China and prepared for light microscopy. The embryological characters studied were qualitatively compared with those of allied taxa via a thorough examination of the existing literature. Early reproductive anatomy in Decaisnea was documented and novel revelations made. It was discovered that the pollen is shed when three-celled (not two-celled, as previously reported), and that endosperm formation is nuclear (not cellular or helobial, as previously reported). These two newly revealed embryological characters are not found in any other members of Lardizabalaceae. Furthermore, neither are persistent antipodal cells, which we confirmed to be present in Decaisnea. Decaisnea and other Lardizabalaceae characteristically have tetrasporangiate anthers, a secretory tapetum, simultaneous microsporocyte cytokinesis, primarily bitegmic, crassinucellate ovules, and a Polygonum type embryo sac. However, in the family, persistent antipodals, nuclear endosperm, and pollen shed at the three-celled stage are only found in Decaisnea. These embryological data prompted the suggestion that Decaisnea needs elevation above the level of genus.
Early reproductive developmental anatomy in Decaisnea (Lardizabalaceae) and its systematic implications

PubMed Central

Wang, Hua-Feng; Friedman, Cynthia Ross; Zhu, Zhi-Xin; Qin, Hai-Ning

2009-01-01

Background and Aims Decaisnea insignis, known as ‘dead man's fingers’ (Lardizabalaceae), is widely distributed in China and the Himalayan foothill countries. This economically important plant, which is the only species in the genus, has not been the subject of any embryological studies aside from one brief, older paper that lacks micrographs. Data on Decaisnea are also important because its systematic position has been unstable since the genus was established in 1855. Therefore, the objectives of this study were: (a) to use modern microscopy to document early reproductive anatomical development in Decaisnea; and (b) to compare qualitatively these early embryological characters with allied taxa in a systematic context. Methods Decaisnea insignis floral buds and inflorescences were regularly collected from Shaanxi Province, China and prepared for light microscopy. The embryological characters studied were qualitatively compared with those of allied taxa via a thorough examination of the existing literature. Key Results Early reproductive anatomy in Decaisnea was documented and novel revelations made. It was discovered that the pollen is shed when three-celled (not two-celled, as previously reported), and that endosperm formation is nuclear (not cellular or helobial, as previously reported). These two newly revealed embryological characters are not found in any other members of Lardizabalaceae. Furthermore, neither are persistent antipodal cells, which we confirmed to be present in Decaisnea. Conclusions Decaisnea and other Lardizabalaceae characteristically have tetrasporangiate anthers, a secretory tapetum, simultaneous microsporocyte cytokinesis, primarily bitegmic, crassinucellate ovules, and a Polygonum type embryo sac. However, in the family, persistent antipodals, nuclear endosperm, and pollen shed at the three-celled stage are only found in Decaisnea. These embryological data prompted the suggestion that Decaisnea needs elevation above the level of genus. PMID:19759039
Anomalies of the middle and inner ear.

PubMed

Rodriguez, Kimsey; Shah, Rahul K; Kenna, Margaret

2007-02-01

The development of the middle and inner ear highlights the intricacy of embryology. As early as 3 weeks after fertilization, the inner ear begins taking form. This process, along with development of the middle ear, continues throughout gestation. At birth, the middle ear, inner ear, and associated structures are almost adult size. An understanding of the embryologic development of the ear serves as a foundation for evaluating and managing congenital malformations of these structures. The focus of this article is the normal, abnormal, and arrested development of the middle and inner ear, with a clinical emphasis on malformed middle and inner ear structures and a discussion of associated syndromes.
Influence of potentially confounding factors on sea urchin porewater toxicity tests

USGS Publications Warehouse

Carr, R.S.; Biedenbach, J.M.; Nipper, M.

2006-01-01

The influence of potentially confounding factors has been identified as a concern for interpreting sea urchin porewater toxicity test data. The results from >40 sediment-quality assessment surveys using early-life stages of the sea urchin Arbacia punctulata were compiled and examined to determine acceptable ranges of natural variables such as pH, ammonia, and dissolved organic carbon on the fertilization and embryological development endpoints. In addition, laboratory experiments were also conducted with A. punctulata and compared with information from the literature. Pore water with pH as low as 6.9 is an unlikely contributor to toxicity for the fertilization and embryological development tests with A. punctulata. Other species of sea urchin have narrower pH tolerance ranges. Ammonia is rarely a contributing factor in pore water toxicity tests using the fertilization endpoint, but the embryological development endpoint may be influenced by ammonia concentrations commonly found in porewater samples. Therefore, ammonia needs to be considered when interpreting results for the embryological development test. Humic acid does not affect sea urchin fertilization at saturation concentrations, but it could have an effect on the embryological development endpoint at near-saturation concentrations. There was no correlation between sediment total organic carbon concentrations and porewater dissolved organic carbon concentrations. Because of the potential for many varying substances to activate parthenogenesis in sea urchin eggs, it is recommended that a no-sperm control be included with every fertilization test treatment. ?? 2006 Springer Science+Business Media, Inc.
The Influence of Hydroxyapatite Nanoparticle Morphology on Embryonic Development in a Zebrafish Exposure Model

PubMed Central

Pujari-Palmer, Shiuli; Lu, Xi; Karlsson Ott, Marjam

2017-01-01

Nanomaterials are used in many different industries such as cosmetics, food, clothing, and electronics. There is increasing concern that exposure to nanoparticles (NPs) during pregnancy can adversely affect fetal development. It is well known that the size, charge, and chemistry of a nanoparticle can modulate embryological development. The role that particle morphology plays on early development, however, is still widely unknown. The present study aims to investigate the effect of hydroxyapatite nanoparticle (HANP) morphology on embryological development in a zebrafish exposure model. Four distinct HANP morphologies (dots, long rods, sheets, and fibers) were fabricated and characterized. Zebrafish embryos were exposed to HANPs (0–100 mg/L), and viability and developmental deformities were evaluated for up to 5 days post-fertilization (dpf). Malformations such as pericardial edema and axial curvature were apparent in embryos as early as 1 dpf, following exposure to the dot and fiber particles, and developed in embryos by 3 dpf in the sheet and long rod particle groups. Minimal death was observed in response to dot, long rod, and sheet particles (≤25%), while fiber particles induced overwhelming toxicity (≤60%) after 1 dpf, and complete toxicity during all subsequent time points. Collectively, these results suggest that nanoparticle morphology can significantly impact embryological development and should be a required consideration when designing nanomaterials for commercial use. PMID:28441729
Emil Godlewski, Jr. (1875-1944) pioneer of embryology at the Jagiellonian University of Krakow (Poland).

PubMed

Sliwa, Leopold

2008-01-01

Emil Godlewski, Jr. (1875-1944) lived and worked in Krakow. He graduated from the Faculty of Medicine of the Jagiellonian University with the title of Doctor of Medical Science. He worked at the Faculty of Medicine, first in the Institute of Descriptive Anatomy and later as Professor of Biology and Embryology in the Department of Biology and Embryology, which he founded and led for many years. After early research on the development and histogenesis of muscles, professor Godlewski's scientific interests focused on regeneration and mechanisms regulating the process of fertilization, as well as early embryo development, blastulation and gastrulation. He was also interested in the origin of the primary differentiating cells in regenerates. He postulated the importance of epithelial tissue in this process and was the first to point out the change in the function, organization and role of the cells under the influence of external stimuli. Investigating fertilization and early development, he focused on the cooperation between the nucleus and the cytoplasm in the regulation of the early stages of development. Godlewski was also the author of the theory of migration of the inherited substances from the nucleus to the cytoplasm and, after their processing, from the cytoplasm to the nucleus. His works were never fragmentary, but always synthetical attempts at explaining important issues relating to the mechanisms of development. In 1936 Professor Godlewski was awarded the title of Member of the Pontifica Accademia delle Scienze. Apart from doing research and teaching, Emil Godlewski devoted a lot of time to social issues, especially those connected to medicine. When Poland regained independence after World War I, he actively participated in the reopening of the Jagiellonian University.
Test of Von Baer's law of the conservation of early development.

PubMed

Poe, Steven

2006-11-01

One of the oldest and most pervasive ideas in comparative embryology is the perceived evolutionary conservation of early ontogeny relative to late ontogeny. Karl Von Baer first noted the similarity of early ontogeny across taxa, and Ernst Haeckel and Charles Darwin gave evolutionary interpretation to this phenomenon. In spite of a resurgence of interest in comparative embryology and the development of mechanistic explanations for Von Baer's law, the pattern itself has been largely untested. Here, I use statistical phylogenetic approaches to show that Von Baer's law is an unnecessarily complex explanation of the patterns of ontogenetic timing in several clades of vertebrates. Von Baer's law suggests a positive correlation between ontogenetic time and amount of evolutionary change. I compare ranked position in ontogeny to frequency of evolutionary change in rank for developmental events and find that these measures are not correlated, thus failing to support Von Baer's model. An alternative model that postulates that small changes in ontogenetic rank are evolutionarily easier than large changes is tentatively supported.
Development of Swallowing and Feeding: Prenatal through First Year of Life

ERIC Educational Resources Information Center

Delaney, Amy L.; Arvedson, Joan C.

2008-01-01

The development of feeding and swallowing involves a highly complex set of interactions that begin in embryologic and fetal periods and continue through infancy and early childhood. This article will focus on swallowing and feeding development in infants who are developing normally with a review of some aspects of prenatal development that provide…
Classics revisited: Dietrich Starck on comparative embryology and placentation.

PubMed

Carter, A M

2017-10-01

Dietrich Starck (1908-2001) was a German embryologist who wrote extensive reviews on comparative placentation. Starck's embryology textbook and his comprehensive review of comparative embryology and placentation give excellent insights into the foundational literature and are extensively referenced. The many original illustrations include placentas from species that are not well described elsewhere. These resources are especially valuable as a portal to the early literature on comparative placentation. Copyright © 2017 Elsevier Ltd. All rights reserved.
The Mexican Axolotl in Schools

ERIC Educational Resources Information Center

Thomas, R. M.

1976-01-01

Suggests and describes laboratory activities in which the Mexican axolotl (Ambystoma mexicanum Shaw) is used, including experiments in embryology and early development, growth and regeneration, neoteny and metamorphosis, genetics and coloration, anatomy and physiology, and behavior. Discusses care and maintenance of animals. (CS)
Hefzibah Eyal-Giladi (1925-2017): over fifty years of embryological research in Israel.

PubMed

Khaner, Oded

2017-01-01

Hefzibah Eyal-Giladi was a creative and innovative pioneering scientist in the creation of the field of early chick embryo development. She had a sharp thinking and enthusiastic attitude, which enabled her to make a deep impression that was highly valued by the general scientific community. Notably, she was a highly successful female researcher in an era which was dominated by male scientists. Her unique personality and keen intellect enabled her to break these borders in a most successful manner. The experiments conducted by her personally, her students and her collaborators served to provide the basic knowledge and paradigms for future scientists in the field, also paving the way for discoveries in other vertebrate model systems. The experimental embryology assays she performed were "old school", examining embryos and explants at a precise morphological level of tissue interactions. In recent years, most of the experimentation in embryology has shifted to molecular and genetic levels. However, the results obtained with these technologically advanced research tools still re-confirm the fundamental findings obtained by Eyal-Giladi using "classic" experimental embryology techniques. Finally, Hefzibah Eyal-Giladi was an outstanding teacher and lecturer. For five decades, she trained and taught generations of undergraduate and graduate students in Israel, exposing them to the field of embryology and developmental biology in the most exciting and enthusiastic way.
A century of cell adhesion: from the blastomere to the clinic part 1: conceptual and experimental foundations and the pre-molecular era.

PubMed

Grunwald, Gerald B

2013-12-01

The historical roots of cell adhesion research stretch back over a hundred years, commencing with fundamental questions from the advent of experimental embryology in the late nineteenth century. The transition of embryology from a descriptive to an experimentally driven and mechanistic branch of the biological sciences included investigations focused on the interactions of the first cells of the newly developing embryo, the blastomeres, and followed the movement, interactions and fate of these cells as the tissues and organs of the growing embryo took form. Of special interest to early investigators were cell-cell contacts, which were obviously dynamic but of an obscure nature. This historical review, the first of a series, explores the early years of the cell adhesion field, including the work of Roux, Wilson, Galtsoff, Just and Holtfreter, and discusses the classical experiments, observations and conceptual developments that formed the cornerstone of cell adhesion research during its premolecular era.
Embryogenesis and laboratory maintenance of the foam-nesting túngara frogs, genus Engystomops (= Physalaemus)

PubMed Central

Romero-Carvajal, Andrés; Sáenz-Ponce, Natalia; Venegas-Ferrín, Michael; Almeida-Reinoso, Diego; Lee, Chanjae; Bond, Jennifer; Ryan, Michael J.; Wallingford, John B.; del Pino, Eugenia M.

2010-01-01

The vast majority of embryological research on amphibians focuses on just a single genus of frogs, Xenopus. To attain a more comprehensive understanding of amphibian development, experimentation on non-model frogs will be essential. Here, we report on the early development, rearing, and embryological analysis of túngara frogs (genus Engystomops, also called Physaleamus). The frogs Engystomops pustulosus, Engystomops coloradorum and Engystomops randi construct floating foam-nests with small eggs. We define a table of 23 stages for the developmental period in the foam-nest. Embryos were immunostained against Lim1, neural, and somite-specific proteins and the expression pattern of RetinoBlastoma Binding Protein 6 (RBBP6) was analyzed by in situ hybridization. Due to their brief life-cycle, frogs belonging to the genus Engystomops are attractive for comparative and genetic studies of development. PMID:19384855
Modeling man: the monkey colony at the Carnegie Institution of Washington's Department of Embryology, 1925-1971.

PubMed

Wilson, Emily K

2012-01-01

Though better recognized for its immediate endeavors in human embryo research, the Carnegie Department of Embryology also employed a breeding colony of rhesus macaques for the purposes of studying human reproduction. This essay follows the course of the first enterprise in maintaining a primate colony for laboratory research and the overlapping scientific, social, and political circumstances that tolerated and cultivated the colony's continued operation from 1925 until 1971. Despite a new-found priority for reproductive sciences in the United States, by the early 1920s an unfertilized human ovum had not yet been seen and even the timing of ovulation remained unresolved. Progress would require an organized research approach that could extend beyond the limitations of working with scant and inherently restrictive human subjects or with common lab mammals like mice. In response, the Department of Embryology, under the Carnegie Institution of Washington (CIW), instituted a novel methodology using a particular primate species as a surrogate in studying normal human reproductive physiology. Over more than 40 years the monkey colony followed an unpremeditated trajectory that would contribute fundamentally to discoveries in human reproduction, early embryo development, reliable birth control methods, and to the establishment of the rhesus macaque as a common model organism.
Generation of the Dimensional Embryology Application (App) for Visualization of Early Chick and Frog Embryonic Development

ERIC Educational Resources Information Center

Webb, Rebecca L.; Bilitski, James; Zerbee, Alyssa; Symans, Alexandra; Chop, Alexandra; Seitz, Brianne; Tran, Cindy

2015-01-01

The study of embryonic development of multiple organisms, including model organisms such as frogs and chicks, is included in many undergraduate biology programs, as well as in a variety of graduate programs. As our knowledge of biological systems increases and the amount of material to be taught expands, the time spent instructing students about…
Reflections on fifty years of publications on the history of general biology and special embryology.

PubMed

Oppenheimer, J M

1975-12-01

The publications of fifty years (1925-1974) of the histroy of biology and embryology are surveyed. In America, the earliest background for work during this period was provided by the collectors, mainly physicians, of books into extensive private libraries. The collectors, for instance Osler, Cushing, and Fulton in this country and Geoffrey Keynes abroad, became expert technical bibliographers during the early part of the half-century under consideration. High standards for medical, thus biological history, insofar as these fields overlap, were also set earlier by Sudhoff's Institut für Geschichte der Medizin in Leipzig, and American historical studies benefited when Sigerist came from Leipzig to Baltimore in the early 1930's. Textbooks of medical history are omitted from discussion here, but a number of more or less general histories of biology published within the specified period are briefly evaluated. The discussion next turns to histories of embryology, general and special. Recent monographs on the classical embryologists, Wolff and von Baer, are enumerated, as are a number of biographies and autobiographies of important embryologists published here or abroad during our half-century. Then general histories of embryology are discussed, and finally some specialized ones. Needham, Roger, and Adelmann are singled out as the most important contributors to the history of embryology, in the West, during the period covered. Few of the contributors to the history of biology and medicine during the years of 1925 through 1974 were trained as historians while students. It is concluded that the History of Science Society has performed an important contribution in professionalizing the history of biology and embryology, but it is pointed out that a great new challenge faces it in the necessity to counteract anti-historical and anti-intellectual moods and movements of today.
Embryological Features of Tofieldia glutinosa and Their Bearing on the Early Diversification of Monocotyledonous Plants

PubMed Central

Holloway, Samuel J.; Friedman, William E.

2008-01-01

Background and Aims Although much is known about the vegetative traits associated with early monocot evolution, less is known about the reproductive features of early monocotyledonous lineages. A study was made of the embryology of Tofieldia glutinosa, a member of an early divergent monocot clade (Tofieldiaceae), and aspects of its development were compared with the development of other early divergent monocots in order to gain insight into defining reproductive features of early monocots. Methods Field-collected developing gynoecial tissues of Tofieldia glutinosa were prepared for histological examination. Over 600 ovules were sectioned and studied using brightfield, differential interference contrast, and fluorescence microscopy. High-resolution digital imaging was used to document important stages of megasporogenesis, megagametogenesis and early endosperm development. Key Results Development of the female gametophyte in T. glutinosa is of a modified Polygonum-type. At maturity the female gametophyte is seven-celled and 11-nucleate with a standard three-celled egg apparatus, a binucleate central cell (where ultimately, the two polar nuclei will fuse into a diploid secondary nucleus) and three binucleate antipodal cells. The antipodal nuclei persist past fertilization, and the process of double fertilization appears to yield a diploid zygote and triploid primary endosperm cell, as is characteristic of plants with Polygonum-type female gametophytes. Endosperm development is helobial, and free-nuclear growth initially proceeds at equal rates in both the micropylar and chalazal endosperm chambers. Conclusions The analysis suggests that the shared common ancestor of monocots possessed persistent and proliferating antipodals similar to those found in T. glutinosa and other early-divergent monocots (e.g. Acorus and members of the Araceae). Helobial endosperm among monocots evolved once in the common ancestor of all monocots excluding Acorus. Thus, the analysis further suggests that helobial endosperm in monocots is homoplasious with those helobial endosperms that are present in water lilies and eudicot angiosperms. PMID:18511412
An analysis of reflective writing early in the medical curriculum: The relationship between reflective capacity and academic achievement.

PubMed

Ottenberg, Abigale L; Pasalic, Dario; Bui, Gloria T; Pawlina, Wojciech

2016-07-01

To examine the relationship between reflection, gender, residency choice, word count, and academic achievement among medical students. A modified version of the Reflection Evaluation for Learners' Enhanced Competencies Tool (REFLECT) was developed and used for this study (Cronbach's alpha of 0.86 with an intraclass correlation coefficient [ICC] of 0.68). This was applied to writing samples about professionalism in gross anatomy from first-year medical students between 2005 and 2011. Four analysts reviewed and scored written reflections independently. Composite reflection scores were compared with gender, residency choice, length of written reflection, NBME® Gross Anatomy and Embryology Subject Examination scores, and final gross anatomy course. Total of 319 written reflections were evaluated. Female students who pursued medicine specialties had the highest composite reflection scores (87 [27.2%]). Word count frequently correlated with reflection score (p < 0.0001). Students who performed well on the NBME® Gross Anatomy and Embryology Subject Examination tended to achieve high anatomy course grades (p < 0.0001). There was no statistically significant relationship between composite reflection scores and NBME® Gross Anatomy and Embryology Subject Examination scores (p = 0.16) or anatomy course grades (p = 0.90). This study suggests there are likely no correlations between reflective capacity and academic performance on tests of medical knowledge administered early in the medical curriculum.

Embryology at the Universities of Lwow and Wroclaw.

PubMed

Ogorzalek, Antoni

2008-01-01

Embryological research at the University of Wroclaw covers hormonal control of metamorphosis, primarily invertebrate embryology and gametogenesis, vertebrate myogenesis and the developmental impact of external factors. Developmental studies at the University of Wroclaw are a continuation of those conducted at the former Jan Kazimierz (Johannes Casimirus) University in Lwow before World War II. The Wroclaw embryological school is best characterized as comparative embryology which approaches embryonic development experimentally as well as through the analysis of its natural diversity.
Clinical embryology teaching: is it relevant anymore?

PubMed

Scott, Karen M; Charles, Antony Robert; Holland, Andrew J A

2013-10-01

Embryology finds itself jostling for precious space in the crowded medical curriculum, yet remains important for helping students understand birth defects. It has been suggested that teaching embryology through clinical scenarios can increase its relevance and interest. The aim of this research was to determine the attitudes of final-year medical students to learning embryology and whether clinical scenarios aid understanding. Final-year medical students undertaking their paediatric rotation in 2009 and 2010 were invited to attend an optional lecture on clinical embryology and participate in the research. In the lecture, three clinical scenarios were presented, in which the lecturer traced the normal development of a foetus and the abnormal development that resulted in a birth defect. Outcomes were assessed quantitatively using a paper-based survey. The vast majority of students who valued embryology teaching in their medical programme thought it would assist them with clinical management, and believed learning through case scenarios helped their understanding. Students were divided in their beliefs about when embryology should be taught in the medical programme and whether it would increase their workload. Embryology teaching appears to be a valuable part of the medical curriculum. Embryology teaching was valued when taught in the clinical environment in later years of the medical programme. Students, clinicians and medical educators should be proactive in finding clinical learning opportunities for embryology teaching. © 2013 Royal Australasian College of Surgeons.
Update on the Notochord Including its Embryology, Molecular Development, and Pathology: A Primer for the Clinician

PubMed Central

Ramesh, Tushar; Nagula, Sai V; Saker, Erfanul; Shoja, Mohammadali; Loukas, Marios; Oskouian, Rod J; Tubbs, R. Shane

2017-01-01

The notochord is a rod-like embryological structure, which plays a vital role in the development of the vertebrate. Though embryological, remnants of this structure have been observed in the nucleus pulposus of the intervertebral discs of normal adults. Pathologically, these remnants can give rise to slow-growing and recurrent notochord-derived tumors called chordomas. Using standard search engines, the literature was reviewed regarding the anatomy, embryology, molecular development, and pathology of the human notochord. Clinicians who interpret imaging or treat patients with pathologies linked to the notochord should have a good working knowledge of its development and pathology. PMID:28480155
[Theoretic and practical content of the clinical embryology].

PubMed

Trávník, P; Hampl, A; Hűttelová, R; Malenovská, A; Priesnitz, J; Rejthar, D; Záková, J

2013-08-01

Clinical embryology is in whole Europe respected health care specialization. The specialists in this field are certified by the European Society of Human Reproduction and Embryology (ESHRE). In the Czech Republic the specialization has been formally established by the Government Order No 31/ 2010 after 30 years unformal existence. Concurrently with the wide development of new techniques in assisted reproduction, there is necessary to define the content of clinical embryology as a health care, scientific and educational discipline. The definition authorized by the Committee of Association of Reproductive Embryology (ARE) is given in this article..
From stem cells to human development: a distinctly human perspective on early embryology, cellular differentiation and translational research.

PubMed

Craft, April M; Johnson, Matthew

2017-01-01

Over 100 scientists with common interests in human development, disease and regeneration gathered in late September 2016 for The Company of Biologists' second 'From Stem Cells to Human Development' meeting held in historic Southbridge. In this Meeting Review, we highlight some of the exciting new findings that were presented, and discuss emerging themes and convergences in human development and disease that arose during these discussions. © 2017. Published by The Company of Biologists Ltd.
Relevance and attitudes toward histology and embryology course through the eyes of freshmen and senior medical students: Experience from Serbia.

PubMed

Zaletel, Ivan; Marić, Gorica; Gazibara, Tatjana; Rakočević, Jelena; Labudović Borović, Milica; Puškaš, Nela; Bajčetić, Miloš

2016-11-01

Histology and embryology are prerequisite for understanding the complexity of cell and tissue organization, function and development. The aim of this study was to examine the attitudes of medical students toward relevance of histology and embryology in their pre-clinical and clinical medical practice. The study sample consisted of 900 undergraduate students of 1st and 6th study year at the School of Medicine in Belgrade, Serbia. Data were collected using an anonymous questionnaire. Senior students reported the relevance of histology and embryology knowledge for learning pathology, dermatology, physiology, gynecology and obstetrics, pathophysiology and pediatrics. Examination of students' attitudes revealed that 1st year participants more often acknowledged histology and embryology as being of great importance for their professional career. Analysis according to gender indicated that female students consider embryology as of greater importance for further medical education and future clinical practice than male students. Overall, study results suggest that medical students have a positive attitude toward histology and embryology undergraduate course. This evidence could be used as an additional motive for the development of histology and embryology courses, with special emphasis on practical application of knowledge in clinically-oriented setting. Copyright © 2016 Elsevier GmbH. All rights reserved.
The Building of Democratic Organizations: An Embryological Metaphor.

ERIC Educational Resources Information Center

Cafferata, Gail Lee

1982-01-01

Patterns of bureaucratization and democratization in voluntary organizations may be explained by four principles of embryology: (1) the irreversibility of embryological development, (2) the canalization or branching of developmental pathways, (3) the induction of developmental change by the interaction of internal stimuli, and (4) the…
The Use of "Kryptolebias marmoratus" Eggs as an Educational Tool for Embryology Education

ERIC Educational Resources Information Center

Genade, Tyrone

2016-01-01

Plastic embryological models lack the excitement of seeing real, live embryos. Chick embryos are often used to demonstrate embryological development and blood circulation to students but this necessitates the death of the organism. "Kryptolebias marmoratus" embryos are large and can be viewed by means of a light microscope without need…
New theory of uterovaginal embryogenesis.

PubMed

Makiyan, Zograb

2016-01-02

The explanation of uterine and vaginal embryogenesis in humans still poses many controversies, because it is difficult to assess early stages of an embryo. The literature review revealed many disagreements in Mullerian theory, inciting some authors to propose new embryological hypotheses. In the original Mullerian theory: the paramesonephral ducts form the Fallopian tubes, uterus and vagina; the mesonephral ducts regress in female embryos. The aim of this article is to investigate the development of Mullerian ducts in humans, using comparative analysis of fundamental embryological theory and various utero-vaginal anomalies. Between 1998 and 2015, 434 patients with various uterovaginal malformations had been operated on at the Scientific Centre of Obstetrics Gynaecology and Perynatology in Moscow. The anatomies of the uterovaginal malformations in these patients were diagnosed with ultrasound and MRI and then verified during surgical correction by laparoscopy. A systematic comparison of uterovaginal malformations to those in the literature has allowed us to formulate a new theory of embryonic morphogenesis. The new theory is significantly different: ovary, ovarian ligamentum proprium, and ligamentum teres uteri derive from gonadal ridges; Fallopian tubes and vagina completely develop from mesonephral ducts. The uterus develops in the area of intersection between the mesonephral ducts with gonadal ridges by the fusion of the two. The new theory may to induce future embryological studies. The hypothetic possibility that the ovary and endometrium derive from the gonadal ridges could be the key to understanding the enigmatic aetiologies of extragenital and ovarian endometriosis.
[Embryology and "official science": the contribution of the anatomical school of José Escolar to embryology during the first Francoism (1939-1959)].

PubMed

Velasco Morgado, Raúl

2015-01-01

In this paper, we analyse the contribution of the anatomical school of José Escolar (1913-1998) to embryology during the first two decades of the Francoist dictatorship. Special attention is paid to the process by which the Spanish group, with the support of the new Superior National Research Council, made contact with the German morphology being developed by Hugo Spatz (1888-1979) at the Max Planck-Institut für Hirnforschung. Our study reveals the numerous influences that finally led to the anatomy and embryology of Escolar. In Spain, we found a direct influence of the Gegenbaurian morphology of Gumersindo Sánchez Guisande (1894-1976) and the neuroanatomy of Juan José Barcia Goyanes (1901-2003), full of references to studies by Braus. International contacts of the "Escolarian group", first with North America and then with Germany, created a homogeneous group with a single anatomy (functional and ontophylogenetic) but with so many research interests that subspecialisations had to be developed. An important embryological work resulted from an intense relationship with the German anatomical community during the 1950s. Escolar worked in this field on the development of the amygdala and allocortex, Fernando Reinoso studied the embryology of the diencephalon and Smith Victor Agreda, along with the German scientist Rudolf Diepen, made some important discoveries on the development of the hypothalamic-pituitary system.
[Scientific revolution and embryology: rejection or transformation of antiquity? A comparison between the procreation teachings of Cesare Cremonini, William Harvey und René Descartes].

PubMed

Lo Presti, Roberto

2014-01-01

In this paper I address the issue of the theoretical and epistemological status of embryology at the rise of the so-called "Scientific Revolution" (also in the first half of the seventeenth-century) and raise the question, in what sense and to what extent the historiographical concept of "Scientific Revolution" is applicable to the domain of embryology. To achieve this aim I compare the theories of three protagonists of the medical, scientific and philosophical debate of that age, namely Cesare Cremonini, William Harvey and René Descartes, who had very different views on the world structure and human nature and a very different concept of science, but who shared, as concerns embryological issues, an epigenetic conception of the development of the embryo. Their theories are discussed and compared in light of following questions: 1) What do Cremonini's, Harvey's and Descartes's embryological theories exactly aim to?; 2) In developing their theories, do these thinkers deal explicitly or implicitly with the Aristotelian and the Galenic embryological paradigm?; 3)Do they refer polemically to the Aristotelian and the Galenic tradition and what theoretical and/or rhetorical function have these polemical references?; 4) Do the embryological theories of Cremonini, Harvey and Descartes reflect the century-long dispute between "(Aristotelian) philosophers" and "(Galenic) doctors"?; 5) How is represented embryology as a 'scientific' and/or 'theoretical' domain? And what relationship between concepts of 'truth', 'research', 'tradition' and 'scientific progress' is implied or proposed in the embryological works of these three thinkers? What kind of use do Cremonini, Harvey and Descartes make of the argumenta ex ratione and of those ex experientia?
A Type I first branchial cleft cyst masquerading as a parotid tumor.

PubMed

Krishnamurthy, Arvind; Ramshanker, Vijayalakshmi

2014-01-01

Branchial cleft anomalies are caused by incomplete regression of the cervical sinus of "His" during the 6(th) and 7(th) weeks of embryologic development. Although congenital in origin, first branchial cleft cysts (FBCCs) can present later in life. FBCCs are rare causes of parotid swellings, accounting for <1% of all the branchial cleft abnormalities. The diagnosis of FBCCs is a clinical challenge; the condition is often overlooked and mismanaged. We report a case of Type 1 FBCC in a 22-year-old female with an asymptomatic 3.5 cm × 2.5 cm sized cystic mass. It was removed completely under the impression of a cystic tumor of the parotid. On histopathology, the cyst had a squamous epithelium-lined wall with lymphoid aggregation which was characteristic of a branchial cleft cyst. A good understanding of the regional anatomy and embryology can lead to an early diagnosis and thereby effective management of FBCC.
Folding into being: early embryology and the epistemology of rhythm.

PubMed

Wellmann, Janina

2015-03-01

Historians have often described embryology and concepts of development in the period around 1800 in terms of "temporalization" or "dynamization". This paper, in contrast, argues that a central epistemological category in the period was "rhythm", which played a major role in the establishment of the emerging discipline of biology. I show that Caspar Friedrich Wolff's epigenetic theory of development was based on a rhythmical notion, namely the hypothesis that organic development occurs as a series of ordered rhythmical repetitions and variations. Presenting Christian Heinrich Pander's and Karl Ernst von Baer's theory of germ layers, I argue that Pander and Baer regarded folding as an organizing principle of ontogenesis, and that the principle's explanatory power stems from their understanding of folding as a rhythmical figuration. In a brief discussion of the notion of rhythm in contemporary music theory, I identify an underlying physiological epistemology in the new musical concept of rhythm around 1800. The paper closes with a more general discussion of the relationship between the rhythmic episteme, conceptions of life, and aesthetic theory at the end of the eighteenth century.
Analysis of the low-molecular weight protein profile of egg-white and its changes during early chicken embryological development.

PubMed

Fang, Jun; Ma, Mei H; Qiu, Ning; Wu, Xiao; Jin, Yong G

2012-01-01

Many low-molecular weight (LMW) proteins in egg-white are potentially bioactive, but the mass range and number of these are not yet fully characterized. The aim of the present study was to map the LMW protein profile in egg-white and provide the basis for further understanding of the physiological function of these proteins. For this purpose, six time points (days 0, 1, 2, 3, 4, 5 of incubation) were selected in an attempt to delineate the LMW proteomic profile in egg-white and its changes during early chicken embryological development. Samples were pretreated using gel chromatography techniques prior to analysis by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). Protein search focused on the mass range m/z 1,000 to 8,000. One hundred and fourteen mass signal peaks of LMW proteins ranging from m/z 1,035.88 to 7,112.91 were detected at all six time points. The observed changes in the LMW protein profile during development were highly dynamic. Eighty six novel mass signal peaks of LMW proteins were generated during incubation, the origin of which could be assigned to the high-molecular weight protein fractions.The list of egg-white LMW proteins provided in this paper is by far the most comprehensive and is intended to serve as a starting point for the isolation and functional characterization of interesting LMW proteins which may play a crucial role in early embryo nutrition and immunity.
Gallbladder Duplication: Evaluation, Treatment, and Classification

DTIC Science & Technology

2010-02-01

2009; revised 16 December 2009; accepted 16 December 2009h o th 0 d Key words: Duplicate gallbladder; Hepatobiliary embryology ; Multiple gallbladders...anatomic variations [5]. These three types vary depending upon the embryologic development and occur in the same manner as duplicated gallbladders. Given... embryology and adds a third group that occurs when there is a combination of types 1 and 2 anatomy. The triple combined group occurs from a split in
History and status of embryology and developmental biology at Polish Medical Faculties and Schools.

PubMed

Bartel, Hieronim

2008-01-01

In Poland, medical embryology (both scientific research and teaching of the subject) has traditionally involved Chairs of Histology and Embryology rather than Obstetrics and Gynecology. Before World War II, the most buoyant centers for embryological research among the five universities at the time (in Warsaw, Krakow, Poznan, Lvov and Vilnius), were the Chairs of Embryology and Histology at Medical Faculties of the Jagiellonian University in Krakow and the University of Vilnius. After World War II, eleven Medical Academies (Universities of Medicine) came into being (Warsaw, Krakow, Poznan, Lodz, Gdansk, Bialystok, Bydgoszcz, Szczecin, Wroclaw, Katowice and Lublin). They conduct scientific research on normal development of the human embryo as well as teratology studies. In the XX century, eminent medicine-related embryologist included professors Emil Godlewski Jr., Stanislaw Hiller and Stefan Baginski.
Embryologic and Fetal Development of the Human Eyelid

PubMed Central

Abdulhafez, Mohamed H.; Fouad, Yousef A.; Dutton, Jonathan J.

2016-01-01

Purpose: To review the recent data about eyelid morphogenesis, and outline a timeline for eyelid development from the very early stages during embryonic life till final maturation of the eyelid late in fetal life. Methods: The authors extensively review major studies detailing human embryologic and fetal eyelid morphogenesis. These studies span almost a century and include some more recent cadaver studies. Numerous studies in the murine model have helped to better understand the molecular signals that govern eyelid embryogenesis. The authors summarize the current findings in molecular biology, and highlight the most significant studies in mice regarding the multiple and interacting signaling pathways involved in regulating normal eyelid morphogenesis. Results: Eyelid morphogenesis involves a succession of subtle yet strictly regulated morphogenetic episodes of tissue folding, proliferation, contraction, and even migration, which may occur simultaneously or in succession. Conclusions: Understanding the extraordinary process of building eyelid tissue in embryonic life, and deciphering its underlying signaling machinery has far reaching clinical implications beyond understanding the developmental abnormalities involving the eyelids, and may pave the way for achieving scar-reducing therapies in adult mammalian wounds, or control the spread of malignancies. PMID:27124372
The need for interaction between assisted reproduction technology and genetics: recommendations of the European Societies of Human Genetics and Human Reproduction and Embryology.

PubMed

2006-08-01

Infertility and reproductive genetic risk are both increasing in our societies because of lifestyle changes and possibly environmental factors. Owing to the magnitude of the problem, they have implications not only at the individual and family levels but also at the community level. This leads to an increasing demand for access to assisted reproduction technology (ART) and genetic services, especially when the cause of infertility may be genetic in origin. The increasing application of genetics in reproductive medicine and vice versa requires closer collaboration between the two disciplines. ART and genetics are rapidly evolving fields where new technologies are currently introduced without sufficient knowledge of their potential long-term effects. As for any medical procedures, there are possible unexpected effects which need to be envisaged to make sure that the balance between benefits and risks is clearly on the benefit side. The development of ART and genetics as scientific activities is creating an opportunity to understand the early stages of human development, which is leading to new and challenging findings/knowledge. However, there are opinions against investigating the early stages of development in humans who deserve respect and attention. For all these reasons, these two societies, European Society of Human Genetics (ESHG) and European Society of Human Reproduction and Embryology (ESHRE), have joined efforts to explore the issues at stake and to set up recommendations to maximize the benefit for the couples in need and for the community.
The Role of Embryologic Fusion Planes in the Invasiveness and Recurrence of Basal Cell Carcinoma: A Classic Mix-Up of Causation and Correlation.

PubMed

Armstrong, Linus T D; Magnusson, Mark R; Guppy, Michelle P B

2015-12-01

The facial embryologic fusion planes as regions of mesenchymal and ectodermal fusion of the primordial facial processes during embryological development have been suggested to influence the spread, invasiveness, pathogenesis, and recurrence of cutaneous carcinoma. This study sought to establish whether basal cell carcinoma (BCC) originating in embryologic fusion planes has a greater propensity for earlier depth of invasion, leading to an increased rate of lesion recurrence. Facial BCCs excised in a single surgeon practice over 2 years were allocated into 2 anatomic domains according to their correlation with embryologic fusion planes. Lesion depth of invasion, surface area, and margins of excision were analyzed in conjunction with recurrence data over the following 70-80 months. Of the 331 lesions examined, 70 were located in embryologic fusion planes. No difference was found in the mean surface area and depth of invasion for lesions located in the 2 domains (P > 0.05). Ten lesion recurrences were identified, none of which were located in embryologic fusion planes. Recurrent lesions were excised with a significantly greater percentage of close and incomplete excision margins (P < 0.05). BCC arising in embryologic fusion planes are not more invasive or at greater risk of recurrence. Excision margins seem to have the greatest influence on lesion recurrence. Because of the paucity of superfluous tissue and the cosmetic and functionally sensitive nature of these areas of embryologic fusion, specialist treatment of these lesions is recommended to ensure that adequacy of excision is not neglected at the cost of ease of closure and cosmesis.
A Type I first branchial cleft cyst masquerading as a parotid tumor

PubMed Central

Krishnamurthy, Arvind; Ramshanker, Vijayalakshmi

2014-01-01

Branchial cleft anomalies are caused by incomplete regression of the cervical sinus of “His” during the 6th and 7th weeks of embryologic development. Although congenital in origin, first branchial cleft cysts (FBCCs) can present later in life. FBCCs are rare causes of parotid swellings, accounting for <1% of all the branchial cleft abnormalities. The diagnosis of FBCCs is a clinical challenge; the condition is often overlooked and mismanaged. We report a case of Type 1 FBCC in a 22-year-old female with an asymptomatic 3.5 cm × 2.5 cm sized cystic mass. It was removed completely under the impression of a cystic tumor of the parotid. On histopathology, the cyst had a squamous epithelium-lined wall with lymphoid aggregation which was characteristic of a branchial cleft cyst. A good understanding of the regional anatomy and embryology can lead to an early diagnosis and thereby effective management of FBCC. PMID:25298726

Foreseeing fates: a commentary on Manton (1928) 'On the embryology of a mysid crustacean, Hemimysis lamornae'.

PubMed

Akam, Michael

2015-04-19

Sidnie Manton became best known for her work on arthropod locomotion, and for proposing radical views on the evolution of arthropods that were accepted for a generation. However, her early training was as an embryologist, and the work that she carried out at the beginning of her career still stands as one of the major twentieth century contributions to the study of crustacean embryology. Here, I review her first major paper, largely completed while she was a graduate student, describing embryonic development in Hemimysis lamornae, a small shrimp-like animal found in the seas around the UK. The clarity of her writing and the quality of her figures set a standard that laid the basis for subsequent work, and although not all of her conclusions have stood the test of time, they remain a standard reference for work today. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society.
Foreseeing fates: a commentary on Manton (1928) ‘On the embryology of a mysid crustacean, Hemimysis lamornae’

PubMed Central

Akam, Michael

2015-01-01

Sidnie Manton became best known for her work on arthropod locomotion, and for proposing radical views on the evolution of arthropods that were accepted for a generation. However, her early training was as an embryologist, and the work that she carried out at the beginning of her career still stands as one of the major twentieth century contributions to the study of crustacean embryology. Here, I review her first major paper, largely completed while she was a graduate student, describing embryonic development in Hemimysis lamornae, a small shrimp-like animal found in the seas around the UK. The clarity of her writing and the quality of her figures set a standard that laid the basis for subsequent work, and although not all of her conclusions have stood the test of time, they remain a standard reference for work today. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society. PMID:25750244
Live dynamic imaging and analysis of developmental cardiac defects in mouse models with optical coherence tomography

NASA Astrophysics Data System (ADS)

Lopez, Andrew L.; Wang, Shang; Garcia, Monica; Valladolid, Christian; Larin, Kirill V.; Larina, Irina V.

2015-03-01

Understanding mouse embryonic development is an invaluable resource for our interpretation of normal human embryology and congenital defects. Our research focuses on developing methods for live imaging and dynamic characterization of early embryonic development in mouse models of human diseases. Using multidisciplinary methods: optical coherence tomography (OCT), live mouse embryo manipulations and static embryo culture, molecular biology, advanced image processing and computational modeling we aim to understand developmental processes. We have developed an OCT based approach to image live early mouse embryos (E8.5 - E9.5) cultured on an imaging stage and visualize developmental events with a spatial resolution of a few micrometers (less than the size of an individual cell) and a frame rate of up to hundreds of frames per second and reconstruct cardiodynamics in 4D (3D+time). We are now using these methods to study how specific embryonic lethal mutations affect cardiac morphology and function during early development.
The educational and professional status of clinical embryology and clinical embryologists in Europe.

PubMed

Kovačič, B; Plas, C; Woodward, B J; Verheyen, G; Prados, F J; Hreinsson, J; De los Santos, M J; Magli, M C; Lundin, K; Plancha, C E

2015-08-01

What is the recognition of clinical embryology and the current status of clinical embryologists in European countries, regarding educational levels, responsibilities and workload, and need for a formal education in assisted reproductive technology (ART)? It is striking that the profession of clinical embryology, almost 40 years after the introduction of IVF, is still not officially recognized in most European countries. Reproductive medicine has developed into a sophisticated multidisciplinary medical branch since the birth of Louise Brown 37 years ago. The European Board & College of Obstetrics and Gynaecology (EBCOG) has recognized reproductive medicine as a subspeciality and has developed a subspeciality training for gynaecologists in collaboration with the European Society for Human Reproduction and Embryology (ESHRE). However, nothing similar exists for the field of clinical embryology or for clinical embryologists. A questionnaire about the situation in clinical embryology in the period of 2012-2013 in the respective European country was sent to ESHRE National representatives (basic scientists only) in December 2013. At this time, 28 European countries had at least one basic scientist in the ESHRE Committee of National Representatives. The survey consisted of 46 numeric, dichotomous (yes/no) or descriptive questions. Answers were obtained from 27 out of 28 countries and the data were tabulated. Data about the numbers of 'ESHRE Certified Embryologists' were taken from the ESHRE Steering Committee for Embryologist Certification. In 2012, more than 7000 laboratory staff from 1349 IVF clinics in 27 European countries performed over 700 000 fresh and frozen ART cycles. Despite this, clinical embryology is only recognized as an official profession in 3 out of 27 national health systems. In most countries clinical embryologists need to be registered under another profession, and have limited possibilities for organized education in clinical embryology. Mostly they are trained for practical work by senior colleagues. ESHRE embryologist certification so far constitutes the only internationally recognized qualification; however this cannot be considered a subspecialization. Data were obtained through different methods, by involving national embryologist societies and cycle registers, collecting information from centre to centre, and in some cases by individual assessment of the situation. For these reasons, the results should be interpreted with caution. This paper presents the current status of clinical embryology and clinical embryologists in Europe and is an important step towards implementation of clinical embryology as an officially recognized profession. None. No. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
The Role of Embryologic Fusion Planes in the Invasiveness and Recurrence of Basal Cell Carcinoma: A Classic Mix-Up of Causation and Correlation

PubMed Central

Armstrong, Linus T. D.; Guppy, Michelle P. B.

2015-01-01

Abstract Background: The facial embryologic fusion planes as regions of mesenchymal and ectodermal fusion of the primordial facial processes during embryological development have been suggested to influence the spread, invasiveness, pathogenesis, and recurrence of cutaneous carcinoma. This study sought to establish whether basal cell carcinoma (BCC) originating in embryologic fusion planes has a greater propensity for earlier depth of invasion, leading to an increased rate of lesion recurrence. Methods: Facial BCCs excised in a single surgeon practice over 2 years were allocated into 2 anatomic domains according to their correlation with embryologic fusion planes. Lesion depth of invasion, surface area, and margins of excision were analyzed in conjunction with recurrence data over the following 70–80 months. Results: Of the 331 lesions examined, 70 were located in embryologic fusion planes. No difference was found in the mean surface area and depth of invasion for lesions located in the 2 domains (P > 0.05). Ten lesion recurrences were identified, none of which were located in embryologic fusion planes. Recurrent lesions were excised with a significantly greater percentage of close and incomplete excision margins (P < 0.05). Conclusions: BCC arising in embryologic fusion planes are not more invasive or at greater risk of recurrence. Excision margins seem to have the greatest influence on lesion recurrence. Because of the paucity of superfluous tissue and the cosmetic and functionally sensitive nature of these areas of embryologic fusion, specialist treatment of these lesions is recommended to ensure that adequacy of excision is not neglected at the cost of ease of closure and cosmesis. PMID:26894007
A combined third and fourth branchial arch anomaly: clinical and embryological implications.

PubMed

Mehrzad, H; Georgalas, C; Huins, C; Tolley, N S

2007-08-01

Embryological abnormalities of the branchial apparatus present an interesting diagnostic and surgical challenge. Thymic cysts are a rare form of branchial apparatus anomaly, resulting from abnormal development of the third pharyngeal pouch. We present two cases of a thymic cyst coexisting with a non recurrent inferior laryngeal nerve (NRILN), two anomalies that to our knowledge have not been associated previously. A possible embryological explication for this double abnormality is discussed, while the clinical implications of this association are presented.
Virtual embryology: a 3D library reconstructed from human embryo sections and animation of development process.

PubMed

Komori, M; Miura, T; Shiota, K; Minato, K; Takahashi, T

1995-01-01

The volumetric shape of a human embryo and its development is hard to comprehend as they have been viewed as a 2D schemes in a textbook or microscopic sectional image. In this paper, a CAI and research support system for human embryology using multimedia presentation techniques is described. In this system, 3D data is acquired from a series of sliced specimens. Its 3D structure can be viewed interactively by rotating, extracting, and truncating its whole body or organ. Moreover, the development process of embryos can be animated using a morphing technique applied to the specimen in several stages. The system is intended to be used interactively, like a virtual reality system. Hence, the system is called Virtual Embryology.
Avians as a model system of vascular development.

PubMed

Bressan, Michael; Mikawa, Takashi

2015-01-01

For more than 2,000 years, philosophers and scientists have turned to the avian embryo with questions of how life begins (Aristotle and Peck Generations of Animals. Loeb Classics, vol. XIII. Harvard University Press, Cambridge, 1943; Needham, A history of embryology. Abelard-Schuman, New York, 1959). Then, as now, the unique accessibility of the embryo both in terms of acquisition of eggs from domesticated fowl and ease at which the embryo can be visualized by simply opening the shell has made avians an appealing and powerful model system for the study of development. Thus, as the field of embryology has evolved through observational, comparative, and experimental embryology into its current iteration as the cellular and molecular biology of development, avians have remained a useful and practical system of study.
Are there symplastic connections between the endosperm and embryo in some angiosperms?--a lesson from the Crassulaceae family.

PubMed

Kozieradzka-Kiszkurno, Małgorzata; Płachno, Bartosz Jan

2012-10-01

It is believed that there is symplastic isolation between the embryo (new sporophyte) and the endosperm (maternal-parental origin tissue, which nourishes the embryo) in angiosperms. However, in embryological literature there are rare examples in which plasmodesmata between the embryo suspensor and endosperm cells have been recorded (three species from Fabaceae). This study was undertaken in order to test the hypothesis that plasmodesmata between the embryo suspensor and the endosperm are not so rare but also occur in other angiosperm families; in order to check this, we used the Crassulaceae family because embryogenesis in Crassulaceae has been studied extensively at an ultrastructure level recently and also we tread members of this family as model for suspensor physiology and function studies. These plasmodesmata even occurred between the basal cell of the two-celled proembryo and endosperm cells. The plasmodesmata were simple at this stage of development. During the development of the embryo proper and the suspensor, the structure of plasmodesmata changes. They were branched and connected with electron-dense material. Our results suggest that in Crassulaceae with plasmodesmata between the endosperm and suspensor, symplastic connectivity at this cell-cell boundary is still reduced or blocked at a very early stage of embryo development (before the globular stage). The occurrence of plasmodesmata between the embryo suspensor and endosperm cells suggests possible symplastic transport between these different organs, at least at a very early stage of embryo development. However, whether this transport actually occurs needs to be proven experimentally. A broader analysis of plants from various families would show whether the occurrence of plasmodesmata between the embryo suspensor and the endosperm are typical embryological characteristics and if this is useful in discussions about angiosperm systematic and evolution.
The double auditory meatus--a rare first branchial cleft anomaly: clinical presentation and treatment.

PubMed

Stokroos, R J; Manni, J J

2000-11-01

To discuss the embryology, classification, clinical experience with, and management of first branchial cleft anomalies. Retrospective case review. Tertiary referral center. Patients with a first branchial cleft anomaly. Surgery or revision surgery. Classifications according to Work, Olsen, Chilla; previous diagnostic and therapeutic pitfalls; outcome of intervention (including facial nerve function). Between 1984 and 1999, first branchial cleft anomalies were diagnosed in 18 patients. Surgical treatment was the treatment of choice. The authors' approach in Work type I and type 2 lesions is described, and surgical aspects of revision surgery are discussed. The importance of early establishment of the relationship of the anomaly to the facial nerve is stressed. In 8 patients, previous surgical attempts had been undertaken without establishment of the diagnosis first. After intervention, the outcome was favorable. First branchial cleft anomalies occur sporadically in ordinary clinical practice. They may go unrecognized or may be mistaken for tumors or other inflammatory lesions of in the periauricular region. However, the distinct clinical features, which can be derived from embryologic development, usually lead to the correct diagnosis. This avoids both treatment delay and eventual failure.
[EEQ in clinical embryology: a starting program].

PubMed

Boyer, Pierre; Brugnon, Florence; Levy, Rachel; Pfeffer, Jérôme; Siest, Jean-Pascal

2014-01-01

Every laboratory including those working in assisted reproductive technologies have to be accredited EN ISO 15189 before 2020. This standardisation includes an external quality evaluation (EQE). In order to work out an EQE tool, we used images extracted from our own database developed during daily practice. We achieved an easily online tool called: "EEQ en embryologie clinique", developed on Biologie prospective web site with ART French biologists Association (Blefco) expertise in evaluation of early human embryonic stages. In 2013, 38 ART laboratories participate to the first program with more than 90% of appropriates results. The present article aims at describing this tool and discussing its limits.
Shared ancestry: using embryology to discover human evolution.

PubMed

Mills, Georgina

2014-04-26

This year's BSAVA lecture was given by Alice Roberts, a clinical anatomist and professor of public engagement in science at the University of Birmingham. Her talk focused around human beings as 'just another animal', and how a shared ancestry between humans and other animals can be shown through embryological development. Georgina Mills reports.
[N.K. Kol'tsov and experimental embryology (dedicated to the 140th anniversary of his birth)].

PubMed

Pomelova, M A

2012-01-01

It is common knowledge that the majority ofN.K. Kol'tsov's studies investigated the structure of a cell through the methods of physical chemistry and cytogenetics. At the same time, Kol'tsov was also interested in the development of experimental biology, specifically experimental embryology.
Part 1: recognizing neonatal spinal cord injury.

PubMed

Brand, M Colleen

2006-02-01

Neonatal spinal cord injury can occur in utero, as well as after either a difficult delivery or a nontraumatic delivery. Spinal cord injury can also be related to invasive nursery procedures or underlying neonatal pathology. Early clinical signs of spinal cord injury that has occurred in utero or at delivery includes severe respiratory compromise and profound hypotonia. Knowledge of risk factors and awareness of symptoms is required for early recognition and appropriate treatment. This article reviews the embryological development of the spinal column highlighting mechanisms of injury and identifying underlying factors that increase the risk of spinal cord injury in newborns. Signs and symptoms of injury, cervical spine immobilization, and the differential diagnosis are discussed. Nursing implications, general prognosis, and research in spinal cord injury are provided.
Crafting socialist embryology: dialectics, aquaculture and the diverging discipline in Maoist China, 1950-1965.

PubMed

Jiang, Lijing

2017-11-07

In the 1950s, embryology in socialist China underwent a series of changes that adjusted the disciplinary apparatus to suit socialism and the national goal of self-reliance. As the Communist state called on scientists to learn from the Soviets, embryologists' comprehensive view on heredity, which did not contradict Trofim Lysenko (1898-1976)'s doctrines, provided a space for them to advance their discipline. Leading scientists, often trained abroad in the tradition of experimental embryology, rode on the tides of Maoist ideology and repositioned their research. Some of their creative realignment of previous research questions, materials, and traditions to Marxist philosophy and agricultural objectives generated productive programs. In particular, Tong Dizhou (1902-1979) translated Engels's dialectics of nature into a research question about cytoplasmic inheritance. His continuing investigation on it led to the first goldfish "clone" through a nuclear transplantation experiment; Zhu Xi and his associates transferred a goldfish model in embryology into studies on improving carp aquaculture, leading to a rare success in the Great Leap Forward of 1958. These directions for embryology continued well into the 1960s. At a time when global embryology was diversifying and began to be molecularized, eventually forming "developmental biology," socialist embryology took shape in China with a different set of epistemic and practical commitments. The history of its development challenges and enriches our understanding of the concrete process of change in one discipline under Mao, showing ways in which scientists creatively adapted state-sanctioned ideologies and visions to do productive work outside the framework of molecular biology during the Cold War.
Embryology of Early Jurassic dinosaur from China with evidence of preserved organic remains.

PubMed

Reisz, Robert R; Huang, Timothy D; Roberts, Eric M; Peng, ShinRung; Sullivan, Corwin; Stein, Koen; LeBlanc, Aaron R H; Shieh, DarBin; Chang, RongSeng; Chiang, ChengCheng; Yang, Chuanwei; Zhong, Shiming

2013-04-11

Fossil dinosaur embryos are surprisingly rare, being almost entirely restricted to Upper Cretaceous strata that record the late stages of non-avian dinosaur evolution. Notable exceptions are the oldest known embryos from the Early Jurassic South African sauropodomorph Massospondylus and Late Jurassic embryos of a theropod from Portugal. The fact that dinosaur embryos are rare and typically enclosed in eggshells limits their availability for tissue and cellular level investigations of development. Consequently, little is known about growth patterns in dinosaur embryos, even though post-hatching ontogeny has been studied in several taxa. Here we report the discovery of an embryonic dinosaur bone bed from the Lower Jurassic of China, the oldest such occurrence in the fossil record. The embryos are similar in geological age to those of Massospondylus and are also assignable to a sauropodomorph dinosaur, probably Lufengosaurus. The preservation of numerous disarticulated skeletal elements and eggshells in this monotaxic bone bed, representing different stages of incubation and therefore derived from different nests, provides opportunities for new investigations of dinosaur embryology in a clade noted for gigantism. For example, comparisons among embryonic femora of different sizes and developmental stages reveal a consistently rapid rate of growth throughout development, possibly indicating that short incubation times were characteristic of sauropodomorphs. In addition, asymmetric radial growth of the femoral shaft and rapid expansion of the fourth trochanter suggest that embryonic muscle activation played an important role in the pre-hatching ontogeny of these dinosaurs. This discovery also provides the oldest evidence of in situ preservation of complex organic remains in a terrestrial vertebrate.
The role of early development in mammalian limb diversification: a descriptive comparison of early limb development between the Natal long-fingered bat (Miniopterus natalensis) and the mouse (Mus musculus).

PubMed

Hockman, Dorit; Mason, Mandy K; Jacobs, David S; Illing, Nicola

2009-04-01

Comparative embryology expands our understanding of unique limb structures, such as that found in bats. Bat forelimb digits 2 to 5 are differentially elongated and joined by webbing, while the hindlimb digits are of similar length in many species. We compare limb development between the mouse and the Natal long-fingered bat, Miniopterus natalensis, to pinpoint the stage at which their limbs begin to differ. The bat forelimb differs from the mouse at Carollia stage (CS) 14 with the appearance of the wing membrane primordia. This difference is enhanced at CS 15 with the posterior expansion of the hand plate. The bat hindlimb begins to differ from the mouse between CS 15 and 16 when the foot plate undergoes a proximal expansion resulting in digit primordia of very similar length. Our findings support recent gene expression studies, which reveal a role for early patterning in the development of the bat limb. Copyright 2009 Wiley-Liss, Inc.
Clinical embryology: is there still a place in medical schools today?

PubMed

Hamilton, J; Carachi, R

2014-11-01

Embryology remains an important tool in medicine and surgery for the management of many clinical conditions. As a subject, it is neither straightforward nor easy to learn and teach in a busy modern medical school curriculum and can be easily overlooked. The aim of this study was to assess medical students' confidence in, and attitudes towards, the learning and teaching of clinical embryology. Medical students from all years of the course were asked to complete an online questionnaire in 2014. The questionnaire focused on confidence levels in learning embryology, methods of teaching, clinical embryology and it also allowed comments. In total, 146 students completed the questionnaire. The majority of students were not confident in learning and applying embryology and were unhappy with current teaching. Despite this, they felt that embryology should be included in the medical school curriculum, in particular clinical embryology with relevant clinical scenarios. Students remain confident that embryology should remain in the medical school curriculum. Embryology should be taught at the right level, depth and through various methods, including basic concepts in the lower years of medical school and moving into clinical embryology later on. As a result, junior doctors and trainees will have a good foundation of knowledge. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
Use of power analysis to develop detectable significance criteria for sea urchin toxicity tests

USGS Publications Warehouse

Carr, R.S.; Biedenbach, J.M.

1999-01-01

When sufficient data are available, the statistical power of a test can be determined using power analysis procedures. The term “detectable significance” has been coined to refer to this criterion based on power analysis and past performance of a test. This power analysis procedure has been performed with sea urchin (Arbacia punctulata) fertilization and embryological development data from sediment porewater toxicity tests. Data from 3100 and 2295 tests for the fertilization and embryological development tests, respectively, were used to calculate the criteria and regression equations describing the power curves. Using Dunnett's test, a minimum significant difference (MSD) (β = 0.05) of 15.5% and 19% for the fertilization test, and 16.4% and 20.6% for the embryological development test, for α ≤ 0.05 and α ≤ 0.01, respectively, were determined. The use of this second criterion reduces type I (false positive) errors and helps to establish a critical level of difference based on the past performance of the test.
Hepatic vascular shunts: embryology and imaging appearances

PubMed Central

Bhargava, P; Vaidya, S; Kolokythas, O; Katz, D S; Dighe, M

2011-01-01

The purpose of this pictorial review is to understand the embryological basis of the development of congenital hepatic vascular shunts and to review the multimodality imaging appearances of congenital and acquired hepatic vascular shunts. Hepatic vascular shunts are commonly seen in imaging. Familiarity with their characteristic appearances is important in order to accurately characterise these shunts and diagnose the underlying disorders. PMID:22101582

A core syllabus for the teaching of embryology and teratology to medical students.

PubMed

Fakoya, Francis A; Emmanouil-Nikoloussi, Elpida; Sharma, Deepak; Moxham, Bernard J

2017-03-01

Clinical relevance in the teaching of biomedical sciences within health care courses presupposes that there is internationally agreed core material within the curricula. However, with the exception of a syllabus for neuroanatomy and gross anatomy of the head and neck for medical students, core syllabuses within many of the specialized anatomical sciences have yet to be developed. The International Federation of Associations of Anatomists aims to formulate internationally accepted core syllabuses for all anatomical sciences disciplines initially using Delphi Panels that comprise anatomists, scientists, and clinicians who evaluate syllabus content. Here, the suggestions of a Delphi Panel for embryology and teratology are presented prior to their publication on the website of the International Federation of Associations of Anatomists. Hence, to obtain a more definitive syllabus, it is required that anatomical and embryological/teratological societies, as well as individual anatomists, embryologists and clinicians, freely comment upon, elaborate and amend, this draft syllabus. The goal is to set internationally recognized standards and thereby provide guidelines concerning embryological and teratological knowledge when involved with course development. Clin. Anat. 30:159-167, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Fabricating a face: the essence of embryology in the dental curriculum.

PubMed

Sperber, G H

2003-03-01

The current explosive growth in developmental biology, fuelled by the almost completed sequencing of the human genome, is bound to have a profound impact upon the practice of medicine and dentistry in the twenty-first century. No other discipline more accurately reflects this impact than embryology, which combines the basic and clinical sciences of genetics, ontogeny, phylogeny, teratology, and syndromology into the essence of modern medical and dental practice. The advent of in vitro fertilization, chorionic villus sampling, amniocentesis, prenatal ultrasonography, intrauterine surgery, and stem cell therapy has vaulted the previously esoteric subject of embryology into clinical consciousness. All these aforementioned procedures require an intimate knowledge of the different stages of development. The alphabet soup of acronyms that now peppers papers proclaiming the genetics and characteristics of various growth factors and cytokines (e.g., FGF, TGFalpha) are all based upon an understanding of the developmental mechanisms occurring in the embryo and subsequently in wound healing and oncology. Congenital abnormalities ranging from lethal syndromes to dental malocclusions cannot be diagnosed, treated, cured, or prognosticated upon without a sound conceptualization of embryology. Computer technology has revolutionized the understanding and teaching of embryology by portraying developmental phenomena as three-dimensional model images in sequential depictions of changes proceeding in the fourth dimension of time. Embryology must now form the essential core of the basic sciences in medical and dental curricula. Future dental practice will become rooted in the genetics and morphogenesis of facial fabrication.
Hitherto unknown detailed muscle anatomy in an 8-week-old embryo.

PubMed

Warmbrunn, Moritz V; de Bakker, Bernadette S; Hagoort, Jaco; Alefs-de Bakker, Pauline B; Oostra, Roelof-Jan

2018-05-03

Congenital muscle diseases, such as myopathies or dystrophies, occur relatively frequently, with estimated incidences of up to 4.7 per 100 000 newborns. To diagnose congenital diseases in the early stages of pregnancy, and to interpret the results of increasingly advanced in utero imaging techniques, a profound knowledge of normal human morphological development of the locomotor system and the nervous system is necessary. Muscular development, however, is an often neglected topic or is only described in a general way in embryology textbooks and papers. To provide the required detailed and updated comprehensive picture of embryologic muscular anatomy, three-dimensional (3D) reconstructions were created based on serial histological sections of a human embryo at Carnegie stage 23 (8 weeks of development, crown-rump length of 23.8 mm), using Amira reconstruction software. Reconstructed muscles, tendons, bones and nerves were exported in a 3D-PDF file to permit interactive viewing. Almost all adult skeletal muscles of the trunk and limbs could be individually identified in their relative adult position. The pectoralis major muscle was divided in three separate muscle heads. The reconstructions showed remarkable highly developed extraocular, infrahyoid and suprahyoid muscles at this age but surprisingly also absence of the facial muscles that have been described to be present at this stage of development. The overall stage of muscle development suggests heterochrony of skeletal muscle development. Several individual muscle groups were found to be developed earlier and in more detail than described in current literature. © 2018 The Authors. Journal of Anatomy published by John Wiley & Sons Ltd on behalf of Anatomical Society.
Embryology training for Reproductive Endocrine fellows in the clinical human embryology laboratory.

PubMed

Scott, Richard T; Hong, Kathleen H; Werner, Marie D; Forman, Eric J; Ruiz, Andrew; Cheng, Michael C; Zhao, Tian; Upham, Kathleen M

2014-04-01

To determine if comprehensive embryology training for clinical Reproductive Endocrinology fellows could be completed to a level of proficiency equivalent to that of experienced embryologists. Clinical fellows were integrated into the clinical embryology team and were trained to perform all the various procedures utilized in clinical embryology. The fellows were trained to the same standards as the clinical embryology staff and underwent the same certification and sign off procedures. To determine if inclusion of clinical fellows on the embryology team impacted outcomes, outcomes for individual oocytes/embryos and the clinical cases where the fellows perform embryology procedures were compared to the outcomes of those oocytes/embryos and cases performed by the full time embryology staff. Clinical procedures performed by the fellows included isolation and processing of oocytes following retrieval, loading catheters for embryo transfer, and vitrification (N = 823 cases). Micromanipulation procedures compared included ICSI and assisted hatching (N = 650 cases). For each procedure, the outcomes in those cases performed by the RE fellows were equivalent to those done by the fully trained clinical embryology staff. When fellows are trained to perform embryology procedures as an integral part of their fellowship curricula, laboratory efficiencies and clinical outcomes are fully maintained. This experience provides valuable insight into the ART process critical to this subspecialty. It also empowers fellows to fully participate in research relating to the viability of gamete and embryos and optimization of the clinical ART laboratory.
[Maurice Herlant (1887-1920), a shooting star of embryology].

PubMed

Louryan, S

2013-01-01

Maurice Herlant (1887-1920) was a Belgian embryologist who worked at the Université libre de Bruxelles during his brief career. He was the assistant of Professor Albert Brachet and was interested by polyspermia and experimental parthenogenesis. His promising career was interrupted by an early death at 33 years of age.
Condensing embryology teaching for medical students: can it be taught in 2 hours?

PubMed

Kazzazi, Fawz; Bartlett, Jonathan

2017-01-01

Embryology forms a valuable part of the medical school curriculum. However, medical students traditionally struggle with revising embryology and appreciating its relevance. Condensing the teaching content, implementing peer-teaching methods, and increasing clinical focus in curricula have been suggested as methods to improve student engagement. Medical students at two universities were taught a condensed version of the embryological curriculum in 2 hours by final-year medical students. Students' confidence with the topics covered in the embryological curricula was assessed using anonymized precourse and postcourse questionnaires. Students were asked to further evaluate the quality, delivery, and content of the teaching in the postcourse questionnaire and were given the opportunity to provide written comments. All questions consisted of a statement stem and a five-point Likert scale. Students scored significantly higher levels of confidence with embryology after implementation of the course. They found the talk to be effectively delivered, clear, and relevant to their examinations. We have demonstrated that it is possible to design and produce an embryology teaching program that covers an undergraduate embryology curriculum in a chronological systems-based manner in 2 hours with successful results.
Condensing embryology teaching for medical students: can it be taught in 2 hours?

PubMed Central

Kazzazi, Fawz; Bartlett, Jonathan

2017-01-01

Introduction Embryology forms a valuable part of the medical school curriculum. However, medical students traditionally struggle with revising embryology and appreciating its relevance. Condensing the teaching content, implementing peer-teaching methods, and increasing clinical focus in curricula have been suggested as methods to improve student engagement. Methods Medical students at two universities were taught a condensed version of the embryological curriculum in 2 hours by final-year medical students. Students’ confidence with the topics covered in the embryological curricula was assessed using anonymized precourse and postcourse questionnaires. Students were asked to further evaluate the quality, delivery, and content of the teaching in the postcourse questionnaire and were given the opportunity to provide written comments. All questions consisted of a statement stem and a five-point Likert scale. Results Students scored significantly higher levels of confidence with embryology after implementation of the course. They found the talk to be effectively delivered, clear, and relevant to their examinations. Conclusion We have demonstrated that it is possible to design and produce an embryology teaching program that covers an undergraduate embryology curriculum in a chronological systems-based manner in 2 hours with successful results. PMID:29270044
NASA Ames Summer High School Apprenticeship Research Program

DTIC Science & Technology

1988-09-01

microorganisms, or by producing mutant bacteria and new breeds, interfering with the original destiny of Jovian evolution. And how would we know, many years...Spacelab mission, Spacelab Japan (SL-J), frog embryos will be fertilized in space in the frog embryology unit (FEU--fig. 3). Knowledge of embryology in...limited to animal embryos that develop quickly, which is necessary in a seven-to-ten-day shuttle flight. The rapid dovelopment of frog embryos makes
Development of the Fish Medaka in Microgravity

NASA Technical Reports Server (NTRS)

Wolgemuth, Debra J.

1995-01-01

The goal of these experiments was to determine the effect of microgravity on the early development of the fish medaka. There were two objectives for this flight series. The primary objective was to assess the effects of microgravity on different stages of development and to ascertain whether the relevant developmental questions can be addressed at the gross morphological level or if the issues involve more subtle questions about regulation at the molecular and cellular levels. The secondary objective was the assessment of the utility of flight hardware with the capabilities to perform embryological studies. We have been able to take advantage of the flight testing phase of the STL-B hardware to also study the effects of microgravity on the early development of the fish, Medaka. Our initial studies involved monitoring the early Medaka development and raising flight embryos for breeding. Images of the developing embryos were collected either via video which was either taken by the astronauts or broadcast to Earth. Sample video images were digitized and stored on a hard drive resident within the on-board STL-B unit. Embryos were fixed at specific intervals, returned to Earth and are being analyzed for the timing and location of molecular events associated with controlling the morphological pattern for the onset of adult structures.
A developmental and genetic classification for midbrain-hindbrain malformations

PubMed Central

Millen, Kathleen J.; Dobyns, William B.

2009-01-01

Advances in neuroimaging, developmental biology and molecular genetics have increased the understanding of developmental disorders affecting the midbrain and hindbrain, both as isolated anomalies and as part of larger malformation syndromes. However, the understanding of these malformations and their relationships with other malformations, within the central nervous system and in the rest of the body, remains limited. A new classification system is proposed, based wherever possible, upon embryology and genetics. Proposed categories include: (i) malformations secondary to early anteroposterior and dorsoventral patterning defects, or to misspecification of mid-hindbrain germinal zones; (ii) malformations associated with later generalized developmental disorders that significantly affect the brainstem and cerebellum (and have a pathogenesis that is at least partly understood); (iii) localized brain malformations that significantly affect the brain stem and cerebellum (pathogenesis partly or largely understood, includes local proliferation, cell specification, migration and axonal guidance); and (iv) combined hypoplasia and atrophy of putative prenatal onset degenerative disorders. Pertinent embryology is discussed and the classification is justified. This classification will prove useful for both physicians who diagnose and treat patients with these disorders and for clinical scientists who wish to understand better the perturbations of developmental processes that produce them. Importantly, both the classification and its framework remain flexible enough to be easily modified when new embryologic processes are described or new malformations discovered. PMID:19933510
Congenital basis of posterior fossa anomalies

PubMed Central

Cotes, Claudia; Bonfante, Eliana; Lazor, Jillian; Jadhav, Siddharth; Caldas, Maria; Swischuk, Leonard

2015-01-01

The classification of posterior fossa congenital anomalies has been a controversial topic. Advances in genetics and imaging have allowed a better understanding of the embryologic development of these abnormalities. A new classification schema correlates the embryologic, morphologic, and genetic bases of these anomalies in order to better distinguish and describe them. Although they provide a better understanding of the clinical aspects and genetics of these disorders, it is crucial for the radiologist to be able to diagnose the congenital posterior fossa anomalies based on their morphology, since neuroimaging is usually the initial step when these disorders are suspected. We divide the most common posterior fossa congenital anomalies into two groups: 1) hindbrain malformations, including diseases with cerebellar or vermian agenesis, aplasia or hypoplasia and cystic posterior fossa anomalies; and 2) cranial vault malformations. In addition, we will review the embryologic development of the posterior fossa and, from the perspective of embryonic development, will describe the imaging appearance of congenital posterior fossa anomalies. Knowledge of the developmental bases of these malformations facilitates detection of the morphological changes identified on imaging, allowing accurate differentiation and diagnosis of congenital posterior fossa anomalies. PMID:26246090
Avians as a Model System of Vascular Development

PubMed Central

Bressan, Michael; Mikawa, Takashi

2015-01-01

Summary For more then 2000 years philosophers and scientists have turned to the avian embryo with questions of how life begins (Aristotle; Needham, 1959). Then, as now, the unique accessibility of the embryo both in terms of acquisition of eggs from domesticated fowl, and ease at which the embryo can be visualized by simply opening the shell, have made avians an appealing and powerful model system for the study of development. Thus, as the field of embryology has evolved through observational, comparative, and experimental embryology, into its current iteration as the cellular and molecular biology of development, avians have remained a useful and practical system of study. PMID:25468608
Why did the savant syndrome not spread in the population? A psychiatric example of a developmental constraint.

PubMed

Ploeger, Annemie; van der Maas, Han L J; Raijmakers, Maartje E J; Galis, Frietson

2009-03-31

A developmental constraint is a mechanism that limits the possibility of a phenotype to evolve. There is growing evidence for the existence of developmental constraints in the biological literature. We hypothesize that a developmental constraint prevents the savant syndrome, despite its positive aspects, from spreading in the population. Here, the developmental constraint is the result of the high interactivity among body parts in an early stage in embryological development, namely early organogenesis or the phylotypic stage. The interactivity during this stage involves all components of the embryo, and as a result mutations that affect one part of the embryo also affect other parts. We hypothesize that a mutation, which gives rise to the development of the positive aspects of the savant syndrome (e.g., an impressive memory capacity), will virtually always have a deleterious effect on the development of other phenotypic traits (e.g., resulting in autism and/or impaired motor coordination). Thus, our hypothesis states that the savant syndrome cannot spread in the population because of this developmental constraint. The finding that children with savant syndrome often have autism and physical anomalies, which are known to be established during early organogenesis, supports our hypothesis.
Space Tissue Loss Configuration B (STL-B)

NASA Technical Reports Server (NTRS)

1998-01-01

The goal of these experiments was to determine the effect of microgravity on the early development of the fish medaka. There were two objectives for this flight series. The primary objective was to assess the effects of microgravity on different stages of development and to ascertain whether the relevant developmental questions can be addressed at the gross morphological level or if the issues involve more subtle questions about regulation at the molecular and cellular levels. The secondary objective was the assessment of the utility of flight hardware with the capabilities to perform embryological studies. We have been able to take advantage of the flight testing phase of the STL-B hardware to also study the effects of microgravity on the early development of the fish, Medaka. Our initial studies involved monitoring the early Medaka development and raising flight embryos for breeding. Images of the developing embryos were collected either via video which was either taken by the astronauts or broadcast to Earth. Sample video images were digitized and stored on a hard drive resident within the on-board STL-B unit. Embryos were fixed at specific intervals, returned to Earth and are being analyzed for the timing and location of molecular events associated with controlling the morphological pattern for the onset of adult structures.
Fossil embryos from the Middle and Late Cambrian period of Hunan, south China.

PubMed

Dong, Xi-Ping; Donoghue, Philip C J; Cheng, Hong; Liu, Jian-Bo

2004-01-15

Comparative embryology is integral to uncovering the pattern and process of metazoan phylogeny, but it relies on the assumption that life histories of living taxa are representative of their antecedents. Fossil embryos provide a crucial test of this assumption and, potentially, insight into the evolution of development, but because discoveries so far lack phylogenetic constraint, their significance is moot. Here we describe a collection of embryos from the Middle and Late Cambrian period (500 million years ago) of Hunan, south China, that preserves stages of development from cleavage to the pre-hatching embryo of a direct-developing animal comparable to living Scalidophora (phyla Priapulida, Kinorhyncha, Loricifera). The latest-stage embryos show affinity to the Lower Cambrian embryo Markuelia, whose life-history strategy contrasts both with the primitive condition inferred for metazoan phyla and with many proposed hypotheses of affinity, all of which prescribe indirect development. Phylogenetic tests based on these embryological data suggest a stem Scalidophora affinity. These discoveries corroborate, rather than contradict, the predictions of comparative embryology, providing direct historical support for the view that the life-history strategies of living taxa are representative of their stem lineages.
Stanislaw Smreczynskis legacy and the Department of Zoology of the Jagiellonian University of Krakow (Poland).

PubMed

Jaglarz, Mariusz K

2008-01-01

This article covers the origin and development of scientific interest in insect and amphibian developmental biology at the Department of Systematic Zoology and Zoogeography of the Jagiellonian University. The greater part of this historical account is devoted to Professor Stanislaw Smreczynski (1899-1975), the founding father of the Department, and comments on his biography and research achievements in the field of animal experimental embryology. A particular emphasis is on Smreczynski's contributions to contemporary understanding of early embryonic development of amphibians and insects as well as his expertise in Pleistocene and extant weevils (Curculionidae). A concise survey of developmental phenomena studied by some of Smreczynski's co-workers and followers is also presented, including the early embryogenesis of entognathans as well as germ cell determination and gonad formation in Drosophila virilis conducted by Jura; analysis of oogenesis in Collembola carried out by Krzysztofowicz; investigations of insects and tradigrades by Weglarska, and finally research into various aspects of ovary structure in diverse insect taxa by the Bilinski group.
Approaches and species in the history of vertebrate embryology.

PubMed

Hopwood, Nick

2011-01-01

Recent debates about model organisms echo far into the past; taking a longer view adds perspective to present concerns. The major approaches in the history of research on vertebrate embryos have tended to exploit different species, though there are long-term continuities too. Early nineteenth-century embryologists worked on surrogates for humans and began to explore the range of vertebrate embryogenesis; late nineteenth-century Darwinists hunted exotic ontogenies; around 1900 experimentalists favored living embryos in which they could easily intervene; reproductive scientists tackled farm animals and human beings; after World War II developmental biologists increasingly engineered species for laboratory life; and proponents of evo-devo have recently challenged the resulting dominance of a few models. Decisions about species have depended on research questions, biological properties, supply lines, and, not least, on methods. Nor are species simply chosen; embryology has transformed them even as they have profoundly shaped the science.
[The Baltic countries as the birthplace of embryology. Contingencies of a transnational region of science].

PubMed

Riha, Ortrun; Schmuck, Thomas

2010-01-01

Modern embryology is grounded on the research of Pander (theory of germ-layers), von Baer (human egg) and Rathke (branchial arches in mammals). All these scientists lived and worked in the Baltic region. They held professorships at the universities of Koenigsberg and Dorpat and at the Imperial Academy of St. Petersburg, thus moving between the Kingdom of Prussia and the Russian Czardom. Since the Baltic countries are not commonly considered to be predestined as a birthplace of embryology, special attention is turned to the coincidences that, there of all places, made those people focus on that special field of research. Considering the peripheral position of the Baltic, the paper examines personal relations, national identities, cultural exchange, and local working conditions, including room for development as well as formidable obstacles.
Extraarticular variants of the long head of the biceps brachii: a reminder of embryology.

PubMed

Audenaert, Emmanuel A; Barbaix, Erik J; Van Hoonacker, Petrus; Berghs, Bart M

2008-01-01

Developmental anomalies of the long head of the biceps tendon are rare and have been described in the literature mainly dealing with anatomy and embryology. Because most basic embryologic research on this topic was conducted before 1966, a literature search was performed from archived anatomy textbooks and manuscript references. These data were compared with the scarce case descriptions of developmental anomalies of the long head of the biceps tendon. An additional case illustration from our own experience was provided. From the literature, it appears that during the embryologic phase of development, a staged migration of the long head of the biceps tendon occurs from a position between the fibrous capsule and synovial layer to an intraarticular position. Recent anatomic and arthroscopic case reports have shown that interruption of this migration can occur in any of these stages. Given the recent increase in arthroscopic shoulder surgery, anomalies of the long head of the biceps tendon will be encountered more frequently. Knowledge of their existence and origin can help in evaluating unexpected anatomic variations or the absence of the biceps tendon in preoperative medical imaging or during an arthroscopic procedure.
Evaluation of biological models using Spacelab

NASA Technical Reports Server (NTRS)

Tollinger, D.; Williams, B. A.

1980-01-01

Biological models of hypogravity effects are described, including the cardiovascular-fluid shift, musculoskeletal, embryological and space sickness models. These models predict such effects as loss of extracellular fluid and electrolytes, decrease in red blood cell mass, and the loss of muscle and bone mass in weight-bearing portions of the body. Experimentation in Spacelab by the use of implanted electromagnetic flow probes, by fertilizing frog eggs in hypogravity and fixing the eggs at various stages of early development and by assessing the role of the vestibulocular reflex arc in space sickness is suggested. It is concluded that the use of small animals eliminates the uncertainties caused by corrective or preventive measures employed with human subjects.

[Double fertilization in flowering plants: 1898-2008].

PubMed

Kordium, E L

2008-01-01

A short review of the results of investigations in the field of plant embryology in vivo and in vitro which are directly connected with the discovery of double fertilization in flowering plants by S.G. Navashin is presented. These results have been obtained by using the methods of electron and fluorescence microscopy, cytophotometry, cultures of isolated ovules, sperms, eggs, and embryo sac central cells. The question on an origin of the female gametophyte of flowering plants, double fertilization, and endosperm are discussed. It is emphasized that the progress in this field is connected mostly with the study of molecular processes which control the development and functioning of a female gametophyte and sporophyte at the early stages of ontogenesis.
Exposure to high ambient temperatures alters embryology in rabbits

NASA Astrophysics Data System (ADS)

García, M. L.; Argente, M. J.

2017-09-01

High ambient temperatures are a determining factor in the deterioration of embryo quality and survival in mammals. The aim of this study was to evaluate the effect of heat stress on embryo development, embryonic size and size of the embryonic coats in rabbits. A total of 310 embryos from 33 females in thermal comfort zone and 264 embryos of 28 females in heat stress conditions were used in the experiment. The traits studied were ovulation rate, percentage of total embryos, percentage of normal embryos, embryo area, zona pellucida thickness and mucin coat thickness. Traits were measured at 24 and 48 h post-coitum (hpc); mucin coat thickness was only measured at 48 hpc. The embryos were classified as zygotes or two-cell embryos at 24 hpc, and 16-cells or early morulae at 48 hpc. The ovulation rate was one oocyte lower in heat stress conditions than in thermal comfort. Percentage of normal embryos was lower in heat stress conditions at 24 hpc (17.2%) and 48 hpc (13.2%). No differences in percentage of zygotes or two-cell embryos were found at 24 hpc. The embryo development and area was affected by heat stress at 48 hpc (10% higher percentage of 16-cells and 883 μm2 smaller, respectively). Zona pellucida was thicker under thermal stress at 24 hpc (1.2 μm) and 48 hpc (1.5 μm). No differences in mucin coat thickness were found. In conclusion, heat stress appears to alter embryology in rabbits.
Developmental diversity in free-living flatworms

PubMed Central

2012-01-01

Flatworm embryology has attracted attention since the early beginnings of comparative evolutionary biology. Considered for a long time the most basal bilaterians, the Platyhelminthes (excluding Acoelomorpha) are now robustly placed within the Spiralia. Despite having lost their relevance to explain the transition from radially to bilaterally symmetrical animals, the study of flatworm embryology is still of great importance to understand the diversification of bilaterians and of developmental mechanisms. Flatworms are acoelomate organisms generally with a simple centralized nervous system, a blind gut, and lacking a circulatory organ, a skeleton and a respiratory system other than the epidermis. Regeneration and asexual reproduction, based on a totipotent neoblast stem cell system, are broadly present among different groups of flatworms. While some more basally branching groups - such as polyclad flatworms - retain the ancestral quartet spiral cleavage pattern, most flatworms have significantly diverged from this pattern and exhibit unique strategies to specify the common adult body plan. Most free-living flatworms (i.e. Platyhelminthes excluding the parasitic Neodermata) are directly developing, whereas in polyclads, also indirect developers with an intermediate free-living larval stage and subsequent metamorphosis are found. A comparative study of developmental diversity may help understanding major questions in evolutionary biology, such as the evolution of cleavage patterns, gastrulation and axial specification, the evolution of larval types, and the diversification and specialization of organ systems. In this review, we present a thorough overview of the embryonic development of the different groups of free-living (turbellarian) platyhelminths, including the Catenulida, Macrostomorpha, Polycladida, Lecithoepitheliata, Proseriata, Bothrioplanida, Rhabdocoela, Fecampiida, Prolecithophora and Tricladida, and discuss their main features under a consensus phylogeny of the phylum. PMID:22429930
Russian comparative embryology takes form: a conceptual metamorphosis toward "evo-devo".

PubMed

Mikhailov, Alexander T

2012-01-01

This essay recapitulates major paths followed by the Russian tradition of what we refer to today as evolutionary developmental biology ("evo-devo"). The article addresses several questions regarding the conceptual history of evolutionary embryological thought in its particularly Russian perspective: (1) the assertion by the St. Petersburg academician Wolff regarding the possible connections between environmental modifications during morphogenesis and the "transformation" of species, (2) the discovery of shared "principles" underlying animal development by von Baer, (3) the experimental expression of Baer's principles by Kowalevsky and Mechnikoff, (4) Severtsov's theory of phylembryogenesis, (5) Filatov's approach to the study of evolution using comparative "developmental mechanics", and (6) Shmalgausen's concept of "stabilizing" selection as an attempt to elucidate the evolution of developmental mechanisms. The focus on comparative evolutionary embryology, which was established by Kowalevsky and Mechnikoff, still continues to be popular in present-day "evo-devo" research in Russia. © 2012 Wiley Periodicals, Inc.
[The neurological and embryological studies of Santiago Ramon y Cajal].

PubMed

Baratas Diaz, L A

1997-01-01

The neurological and embryological work of Santiago Ramon y Cajal appeared in three stages: a) Between 1888 and 1893 observations on the development of neuron prolongations led to the observation of the growth cone and formulation of the neurotropic hypothesis. b) Between 1905 and 1908 the study of regenerative phenomena in nerves and nervours centers presented a large body of evidence consistent with the neurotropic hypothesis. c)Between 1910 and 1914 an experimental program was undertaken to test the neurotropic hypothesis; this program led to conclusions on the origin and chemical nature of the growth stimulating factor. These contributions initiated an important line of research that none of Ramon y Cajal's disciples could continue. In the nineteen fifties a group of researchers from three disciplines (biochemistry, embryology and neurohistology) discovered the existence of nerve growth factor (NGF), thus initiating a fertile new field of knowledge in cell biology.
Branchial cleft anomalies: a pictorial review of embryological development and spectrum of imaging findings.

PubMed

Adams, Ashok; Mankad, Kshitij; Offiah, Curtis; Childs, Lucy

2016-02-01

The branchial arches are the embryological precursors of the face, neck and pharynx. Anomalies of the branchial arches are the second most common congenital lesions of the head and neck in children, with second branchial arch anomalies by far the most common. Clinically, these congenital anomalies may present as cysts, sinus tracts, fistulae or cartilaginous remnants with typical clinical and radiological findings. We review the normal embryological development of the branchial arches and the anatomical structures of the head and neck that derive from each arch. The typical clinical and radiological appearances of both common and uncommon branchial arch abnormalities are discussed with an emphasis on branchial cleft anomalies. • Anomalies of the branchial arches usually present as cysts, sinuses or fistulae. • Second branchial arch anomalies account for approximately 95 % of cases. • There are no pathognomonic imaging features so diagnosis depends on a high index of suspicion and knowledge of typical locations. • Persistent cysts, fistulae or recurrent localised infection may be due to branchial arch anomalies. • Surgical excision of the cyst or tract is the most common curative option.
My Corporis Fabrica Embryo: An ontology-based 3D spatio-temporal modeling of human embryo development.

PubMed

Rabattu, Pierre-Yves; Massé, Benoit; Ulliana, Federico; Rousset, Marie-Christine; Rohmer, Damien; Léon, Jean-Claude; Palombi, Olivier

2015-01-01

Embryology is a complex morphologic discipline involving a set of entangled mechanisms, sometime difficult to understand and to visualize. Recent computer based techniques ranging from geometrical to physically based modeling are used to assist the visualization and the simulation of virtual humans for numerous domains such as surgical simulation and learning. On the other side, the ontology-based approach applied to knowledge representation is more and more successfully adopted in the life-science domains to formalize biological entities and phenomena, thanks to a declarative approach for expressing and reasoning over symbolic information. 3D models and ontologies are two complementary ways to describe biological entities that remain largely separated. Indeed, while many ontologies providing a unified formalization of anatomy and embryology exist, they remain only descriptive and make the access to anatomical content of complex 3D embryology models and simulations difficult. In this work, we present a novel ontology describing the development of the human embryology deforming 3D models. Beyond describing how organs and structures are composed, our ontology integrates a procedural description of their 3D representations, temporal deformation and relations with respect to their developments. We also created inferences rules to express complex connections between entities. It results in a unified description of both the knowledge of the organs deformation and their 3D representations enabling to visualize dynamically the embryo deformation during the Carnegie stages. Through a simplified ontology, containing representative entities which are linked to spatial position and temporal process information, we illustrate the added-value of such a declarative approach for interactive simulation and visualization of 3D embryos. Combining ontologies and 3D models enables a declarative description of different embryological models that capture the complexity of human developmental anatomy. Visualizing embryos with 3D geometric models and their animated deformations perhaps paves the way towards some kind of hypothesis-driven application. These can also be used to assist the learning process of this complex knowledge. http://www.mycorporisfabrica.org/.
Median raphe cysts of the perineum in children.

PubMed

Krauel, Lucas; Tarrado, Xavier; Garcia-Aparicio, Luis; Lerena, Javier; Suñol, Mariona; Rodó, Joan; Ribó, Josep Maria

2008-05-01

Median raphe cysts of the perineum are uncommon congenital lesions of the male genitalia. They can be found all the way from the distal penis and scrotum toward the perineum in a midline position. They are considered as congenital alterations in embryologic development. A case of a 6 year-old boy is presented. Review of the literature relevant to children was made regarding the embryologic, diagnostic, and treatment aspects. We believe it is important that adult and pediatric urologists recognize these lesions and their management to provide the appropriate information to the parents.
Anatomy and embryology of umbilicus in newborns: a review and clinical correlations.

PubMed

Hegazy, Abdelmonem A

2016-09-01

Umbilicus is considered a mirror of the abdomen in newborns. Despite its importance, the umbilicus has been stated in literature and textbooks as discrete subjects with many body systems, such as the urinary, digestive, and cardiovascular ones. This article aimed to address the basic knowledge of the umbilicus in relation to clinical disorders under one integrated topic to aid physicians and surgeons in assessing newborns and infants. The umbilicus appears as early as the fourth week of fetal life when the folding of the embryonic plate occurs. The umbilicus appears initially as a primitive umbilical ring on the ventral aspect of the body. The primitive umbilicus contains the connecting stalk, umbilical vessels, vitelline duct and vessels, allantois, and loop of the intestine. Changes occur to form the definitive cord, which contains three umbilical vessels, namely, "one vein and two arteries," embedded in Wharton's jelly. After birth, the umbilical vessels inside the body obliterate and gradually form ligaments. Congenital disorders at the umbilicus include herniation, bleeding, and discharge of mucous, urine, or feces. Some of these disorders necessitate emergent surgical interference, whereas others may be managed conservatively. The umbilicus has many embryological remnants. Thus, the umbilicus is prone to various clinical disorders. Detecting these disorders as early as possible is essential to prevent or minimize possible complications.
Different effectiveness of closed embryo culture system with time-lapse imaging (EmbryoScope(TM)) in comparison to standard manual embryology in good and poor prognosis patients: a prospectively randomized pilot study.

PubMed

Wu, Yan-Guang; Lazzaroni-Tealdi, Emanuela; Wang, Qi; Zhang, Lin; Barad, David H; Kushnir, Vitaly A; Darmon, Sarah K; Albertini, David F; Gleicher, Norbert

2016-08-24

Previously manual human embryology in many in vitro fertilization (IVF) centers is rapidly being replaced by closed embryo incubation systems with time-lapse imaging. Whether such systems perform comparably to manual embryology in different IVF patient populations has, however, never before been investigated. We, therefore, prospectively compared embryo quality following closed system culture with time-lapse photography (EmbryoScope™) and standard embryology. We performed a two-part prospectively randomized study in IVF (clinical trial # NCT92256309). Part A involved 31 infertile poor prognosis patients prospectively randomized to EmbryoScope™ and standard embryology. Part B involved embryos from 17 egg donor-recipient cycles resulting in large egg/embryo numbers, thus permitting prospectively alternative embryo assignments to EmbryoScope™ and standard embryology. We then compared pregnancy rates and embryo quality on day-3 after fertilization and embryologist time utilized per processed embryo. Part A revealed in poor prognosis patients no differences in day-3 embryo scores, implantation and clinical pregnancy rates between EmbryoScope™ and standard embryology. The EmbryoScope™, however, more than doubled embryology staff time (P < 0.0001). In Part B, embryos grown in the EmbyoScope™ demonstrated significantly poorer day-3 quality (depending on embryo parameter between P = 0.005 and P = 0.01). Suspicion that conical culture dishes of the EmbryoScope™ (EmbryoSlide™) may be the cause was disproven when standard culture dishes demonstrated no outcome difference in standard incubation. Though due to small patient numbers preliminary, this study raises concerns about the mostly uncontrolled introduction of closed incubation systems with time lapse imaging into routine clinical embryology. Appropriately designed and powered prospectively randomized studies appear urgently needed in well-defined patient populations before the uncontrolled utilization of these instruments further expands. NCT02246309 Registered September 18, 2014.
Patenting humans: clones, chimeras, and biological artifacts.

PubMed

Hurlbut, William B

2005-01-01

The momentum of advances in biology is evident in the history of patents on life forms. As we proceed forward with greater understanding and technological control of developmental biology there will be many new and challenging dilemmas related to patenting of human parts and partial trajectories of human development. These dilemmas are already evident in the current conflict over the moral status of the early human embryo. In this essay, recent evidence from embryological studies is considered and the unbroken continuity of organismal development initiated at fertilization is asserted as clear and reasonable grounds for moral standing. Within this frame of analysis, it is proposed that through a technique of Altered Nuclear Transfer, non-organismal entities might be created from which embryonic stem cells could be morally procured. Criteria for patenting of such non-organismal entities are considered.
Learning to Fish with Genetics: A Primer on the Vertebrate Model Danio rerio

PubMed Central

Holtzman, Nathalia G.; Iovine, M. Kathryn; Liang, Jennifer O.; Morris, Jacqueline

2016-01-01

In the last 30 years, the zebrafish has become a widely used model organism for research on vertebrate development and disease. Through a powerful combination of genetics and experimental embryology, significant inroads have been made into the regulation of embryonic axis formation, organogenesis, and the development of neural networks. Research with this model has also expanded into other areas, including the genetic regulation of aging, regeneration, and animal behavior. Zebrafish are a popular model because of the ease with which they can be maintained, their small size and low cost, the ability to obtain hundreds of embryos on a daily basis, and the accessibility, translucency, and rapidity of early developmental stages. This primer describes the swift progress of genetic approaches in zebrafish and highlights recent advances that have led to new insights into vertebrate biology. PMID:27384027
Iconoclasts of Evolution: Haeckel, Behe, Wells & the Ontogeny of a Fraud

ERIC Educational Resources Information Center

Pickett, Kurt M.; Wenzel, John W.; Rissing, Steven W.

2005-01-01

Behe (1998) and Wells (1999) claimed that embryological support for Darwinian evolution is based on the drawings of the 19th century embryologist Ernst Haeckel (1834-1919) whose embryological drawings were regarded inaccurate and fraudulent. The history of modern embryology, the roles played by Von Baer and Haeckel in that history and the manner…
A retrospective look at replacing face-to-face embryology instruction with online lectures in a human anatomy course.

PubMed

Beale, Elmus G; Tarwater, Patrick M; Lee, Vaughan H

2014-01-01

Embryology is integrated into the Clinically Oriented Anatomy course at the Texas Tech University Health Sciences Center School of Medicine. Before 2008, the same instructor presented embryology in 13 face-to-face lectures distributed by organ systems throughout the course. For the 2008 and 2009 offerings of the course, a hybrid embryology instruction model with four face-to-face classes that supplemented online recorded lectures was used. One instructor delivered the lectures face-to-face in 2007 and by online videos in 2008-2009, while a second instructor provided the supplemental face-to-face classes in 2008-2009. The same embryology learning objectives and selected examination questions were used for each of the three years. This allowed direct comparison of learning outcomes, as measured by examination performance, for students receiving only face-to-face embryology instruction versus the hybrid approach. Comparison of the face-to-face lectures to the hybrid approach showed no difference in overall class performance on embryology questions that were used all three years. Moreover, there was no differential effect of the delivery method on the examination scores for bottom quartile students. Students completed an end-of-course survey to assess their opinions. They rated the two forms of delivery similarly on a six-point Likert scale and reported that face-to-face lectures have the advantage of allowing them to interact with the instructor, whereas online lectures could be paused, replayed, and viewed at any time. These experiences suggest the need for well-designed prospective studies to determine whether online lectures can be used to enhance the efficacy of embryology instruction. © 2013 American Association of Anatomists.
Three dimensional ultrasound and hdlive technology as possible tools in teaching embryology.

PubMed

Popovici, Razvan; Pristavu, Anda; Sava, Anca

2017-10-01

Embryology is an important subject in order to gain an understanding of medicine and surgery; however, sometimes students find the subject difficult to grasp and apply to clinical practice. Modern imaging techniques can be useful aids in teaching and understanding embryology. Imaging techniques have very rapidly evolved over the last few years, advancing from two- to three-dimensional (3D) ultrasound. HDlive is an innovative ultrasound technique that generates near-realistic images of the human fetus. In order to evince the capabilities of 3D ultrasound and HDlive technology in teaching embryology, we evaluated using this technique the normal evolution of the embryo and fetus from the fifth to eleventh week of amenorrhea. Our conclusion is that by yielding clear and impressive images, 3D ultrasound and HDlive could be useful tools in teaching embryology to medical students. Clin. Anat. 30:953-957, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
A Retrospective Look at Replacing Face-to-Face Embryology Instruction with Online Lectures in a Human Anatomy Course

ERIC Educational Resources Information Center

Beale, Elmus G.; Tarwater, Patrick M.; Lee, Vaughan H.

2014-01-01

Embryology is integrated into the Clinically Oriented Anatomy course at the Texas Tech University Health Sciences Center School of Medicine. Before 2008, the same instructor presented embryology in 13 face-to-face lectures distributed by organ systems throughout the course. For the 2008 and 2009 offerings of the course, a hybrid embryology…
Midline cystic malformations of the brain: imaging diagnosis and classification based on embryologic analysis.

PubMed

Utsunomiya, Hidetsuna; Yamashita, Shinichi; Takano, Koichi; Ueda, Yukiyo; Fujii, Akira

2006-07-01

This article describes a classification and imaging diagnosis of intracranial midline cystic malformations based on neuroembryologic analysis. Midline cystic malformations are classified into two categories from an embryologic point of view. In one category, the cyst represents expansion of the roof plate of the brain vesicle, and in the other the cyst consists of extraaxial structures such as an arachnoid membrane or migrating ependymal cells. Infratentorial cysts, such as the Dandy-Walker cyst or Blake's pouch cyst, and supratentorial cysts, such as a communicating interhemispheric cyst with callosal agenesis or a dorsal cyst with holoprosencephaly, are included in the first category. Infratentorial arachnoid cavities, such as the arachnoid cyst, arachnoid pouch, and mega cisterna magna, are in the second category. Noncommunicating interhemispheric cysts, such as interhemispheric arachnoid cyst or ependymal cyst, with callosal agenesis are also in the second category. A careful review of embryologic development is essential for understanding these midline cysts and for making a more accurate radiologic diagnosis.
Conceptions of Prenatal Development: Behavioral Embryology

ERIC Educational Resources Information Center

Gottlieb, Gilbert

1976-01-01

Describes recent progress in research on prenatal behavioral development and in a systematic fashion the various ways in which prenatal experience can affect the development of behavior in the neonate as well as in the embryo and fetus. (Author/RK)
Accurate diagnosis of prenatal cleft lip/palate by understanding the embryology

PubMed Central

Smarius, Bram; Loozen, Charlotte; Manten, Wendy; Bekker, Mireille; Pistorius, Lou; Breugem, Corstiaan

2017-01-01

Cleft lip with or without cleft palate (CP) is one of the most common congenital malformations. Ultrasonographers involved in the routine 20-wk ultrasound screening could encounter these malformations. The face and palate develop in a very characteristic way. For ultrasonographers involved in screening these patients it is crucial to have a thorough understanding of the embryology of the face. This could help them to make a more accurate diagnosis and save time during the ultrasound. Subsequently, the current postnatal classification will be discussed to facilitate the communication with the CP teams. PMID:29026689
Embryological origin of the endocardium and derived valve progenitor cells: from developmental biology to stem cell-based valve repair.

PubMed

Pucéat, Michel

2013-04-01

The cardiac valves are targets of both congenital and acquired diseases. The formation of valves during embryogenesis (i.e., valvulogenesis) originates from endocardial cells lining the myocardium. These cells undergo an endothelial-mesenchymal transition, proliferate and migrate within an extracellular matrix. This leads to the formation of bilateral cardiac cushions in both the atrioventricular canal and the outflow tract. The embryonic origin of both the endocardium and prospective valve cells is still elusive. Endocardial and myocardial lineages are segregated early during embryogenesis and such a cell fate decision can be recapitulated in vitro by embryonic stem cells (ESC). Besides genetically modified mice and ex vivo heart explants, ESCs provide a cellular model to study the early steps of valve development and might constitute a human therapeutic cell source for decellularized tissue-engineered valves. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Cardiac Pathways of Differentiation, Metabolism and Contraction. Copyright © 2012 Elsevier B.V. All rights reserved.

Embryology of Pera (Peraceae, Malpighiales): systematics and evolutionary implications.

PubMed

de Olivera Franca, Rafael; De-Paula, Orlando Cavalari

2017-07-01

Pera is a neotropical genus that currently belongs to the family Peraceae. This circumscription resulted from an inclusion of the Rafflesiaceae between the old tribe Pereae and all other Euphorbiaceae, and wherein Pereae was elevated to family rank making Euphorbiaceae monophyletic again. These changes are necessary although Rafflesiaceae are holoparasitic with extremely reduced vegetative bodies and large flowers while Peraceae and Euphorbiaceae have well developed vegetative parts and reduced flowers. As the embryology of Peraceae was poorly known, and embryological processes are conservative, we studied the embryology of Pera glabrata, searching for similarities between Peraceae, Rafflesiaceae, and Euphorbiaceae that could support this grouping. Usual methods of light microscopy and scanning electron microscopy were utilised. The results show endothecium with reversed-T-shaped cells, prismatic crystals in the tapetum, and disintegrated aerenchymatous septum in the mature fruit as unique features for Peraceae and possibly apomorphies for the family. In addition to the unisexual flowers, porogamous fertilization is present and one ovule per carpel which may support the Peraceae-Rafflesiaceae-Euphorbiaceae clade. The comparative approach also suggests possible (syn-)apomorphies for linoids and phyllanthoids, only linoids, Rafflesiaceae, Euphorbiaceae, and Ixonanthaceae. The presence of a placental obturator found previously unknown in Peraceae emerged as a possible synapomorphy for the euphorbioids (including Ixonanthaceae, Linaceae, Phyllanthaceae, Picrodendraceae, Peraceae, Rafflesiaceae, and Euphorbiaceae), which appeared in a common ancestor of the group and has been lost in Rafflesiaceae.
Cranial dural arteriovenous shunts. Part 1. Anatomy and embryology of the bridging and emissary veins.

PubMed

Baltsavias, Gerasimos; Parthasarathi, Venkatraman; Aydin, Emre; Al Schameri, Rahman A; Roth, Peter; Valavanis, Anton

2015-04-01

We reviewed the anatomy and embryology of the bridging and emissary veins aiming to elucidate aspects related to the cranial dural arteriovenous fistulae. Data from relevant articles on the anatomy and embryology of the bridging and emissary veins were identified using one electronic database, supplemented by data from selected reference texts. Persisting fetal pial-arachnoidal veins correspond to the adult bridging veins. Relevant embryologic descriptions are based on the classic scheme of five divisions of the brain (telencephalon, diencephalon, mesencephalon, metencephalon, myelencephalon). Variation in their exact position and the number of bridging veins is the rule and certain locations, particularly that of the anterior cranial fossa and lower posterior cranial fossa are often neglected in prior descriptions. The distal segment of a bridging vein is part of the dural system and can be primarily involved in cranial dural arteriovenous lesions by constituting the actual site of the shunt. The veins in the lamina cribriformis exhibit a bridging-emissary vein pattern similar to the spinal configuration. The emissary veins connect the dural venous system with the extracranial venous system and are often involved in dural arteriovenous lesions. Cranial dural shunts may develop in three distinct areas of the cranial venous system: the dural sinuses and their interfaces with bridging veins and emissary veins. The exact site of the lesion may dictate the arterial feeders and original venous drainage pattern.
A multimedia approach for teaching human embryology: Development and evaluation of a methodology.

PubMed

Moraes, Suzana Guimarães; Pereira, Luis Antonio Violin

2010-12-20

Human embryology requires students to understand the simultaneous changes in embryos, but students find it difficult to grasp the concepts presented and to visualise the related processes in three dimensions. The aims of this study have been to develop and evaluate new educational materials and a teaching methodology based on multimedia approaches to improve the comprehension of human development. The materials developed at the State University of Campinas include clinical histories, movies, animations, and ultrasound, as well as autopsy images from embryos and foetuses. The series of embryology lectures were divided into two parts. The first part of the series addressed the development of the body's structures, while in the second part, clinical history and the corresponding materials were shown to the students, who were encouraged to discuss the malformations. The teaching materials were made available on software used by the students in classes. At the end of the discipline, the material and methodology were evaluated with an attitudinal instrument, interviews, and knowledge examination. The response rate to the attitudinal instrument was 95.35%, and the response rate to the interview was 46%. The students approved of the materials and the teaching methodology (reliability of the attitudinal instrument was 0.9057). The exams showed that most students scored above 6.0. A multimedia approach proved useful for solving an important problem associated with teaching methods in many medical institutions: the lack of integration between basic sciences and clinical disciplines. 2010 Elsevier GmbH. All rights reserved.
Human Embryology and the Holy Quran: An Overview

PubMed Central

Saadat, Sabiha

2009-01-01

Man’s quest to know about his origin has led him to search his roots and the best source for him has been religious scriptures. The greatest miracle is the Holy Quraan. There is an elegant description of origin, development and step by step developmental stages of intra-uterine life in Quraan. Muslims had this knowledge in 7th century and the Prophet Muhammad’s Ahadeeth (sayings, deeds, approvals narrated by authentic narrators) had explained almost everything about natal and even postnatal events. These findings once presented to experts in the field of Anatomy and Embryology surprised them and they believed that the knowledge given to the Prophet Muhammad was indeed divine. Who else would provide this knowledge to the Prophet Muhammad (PBUH) except the Creator Himself. Modern embryology is a fairly recent development which has its beginning with the invention of microscope in the 17th century. However the concept of the human being developing in stages was not recognised until much later. But the scientists then and most Muslim and non-Muslim scholars do not even know that the holy Quran and Sunnah [words, deeds, approvals of Prophet Muhammad (PBUH) collected by authentic narrators] had provided a detailed description of the significant events in human development from the stages of gametes and conception until the full term pregnancy and delivery or even post partum. Actually information in the Quran and Hadith corrected many superstitious and vague ideas about human development that were prevalent before. PMID:21475518
Human embryology and the holy quran: an overview.

PubMed

Saadat, Sabiha

2009-01-01

Man's quest to know about his origin has led him to search his roots and the best source for him has been religious scriptures. The greatest miracle is the Holy Quraan. There is an elegant description of origin, development and step by step developmental stages of intra-uterine life in Quraan. Muslims had this knowledge in 7th century and the Prophet Muhammad's Ahadeeth (sayings, deeds, approvals narrated by authentic narrators) had explained almost everything about natal and even postnatal events. These findings once presented to experts in the field of Anatomy and Embryology surprised them and they believed that the knowledge given to the Prophet Muhammad was indeed divine. Who else would provide this knowledge to the Prophet Muhammad (PBUH) except the Creator Himself.Modern embryology is a fairly recent development which has its beginning with the invention of microscope in the 17th century. However the concept of the human being developing in stages was not recognised until much later. But the scientists then and most Muslim and non-Muslim scholars do not even know that the holy Quran and Sunnah [words, deeds, approvals of Prophet Muhammad (PBUH) collected by authentic narrators] had provided a detailed description of the significant events in human development from the stages of gametes and conception until the full term pregnancy and delivery or even post partum. Actually information in the Quran and Hadith corrected many superstitious and vague ideas about human development that were prevalent before.
A Functional Perspective on the Embryology and Anatomy of the Cerebral Blood Supply

PubMed Central

Menshawi, Khaled; Mohr, Jay P

2015-01-01

The anatomy of the arterial system supplying blood to the brain can influence the development of arterial disease such as aneurysms, dolichoectasia and atherosclerosis. As the arteries supplying blood to the brain develop during embryogenesis, variation in their anatomy may occur and this variation may influence the development of arterial disease. Angiogenesis, which occurs mainly by sprouting of parent arteries, is the first stage at which variations can occur. At day 24 of embryological life, the internal carotid artery is the first artery to form and it provides all the blood required by the primitive brain. As the occipital region, brain stem and cerebellum enlarge; the internal carotid supply becomes insufficient, triggering the development of the posterior circulation. At this stage, the posterior circulation consists of a primitive mesh of arterial networks that originate from projection of penetrators from the distal carotid artery and more proximally from carotid-vertebrobasilar anastomoses. These anastomoses regress when the basilar artery and the vertebral arteries become independent from the internal carotid artery, but their persistence is not uncommon in adults (e.g., persistent trigeminal artery). Other common remnants of embryological development include fenestration or duplication (most commonly of the basilar artery), hypoplasia (typically of the posterior communicating artery) or agenesis (typically of the anterior communicating artery). Learning more about the hemodynamic consequence that these variants may have on the brain territories they supply may help understand better the underlying physiopathology of cerebral arterial remodeling and stroke in patients with these variants. PMID:26060802
A history of normal plates, tables and stages in vertebrate embryology

PubMed Central

HOPWOOD, NICK

2006-01-01

Developmental biology is today unimaginable without the normal stages that define standard divisions of development. This history of normal stages, and the related normal plates and normal tables, shows how these standards have shaped and been shaped by disciplinary change in vertebrate embryology. The article highlights the Normal Plates of the Development of the Vertebrates edited by the German anatomist Franz Keibel (16 volumes, 1897–1938). These were a major response to problems in the relations between ontogeny and phylogeny that amounted in practical terms to a crisis in staging embryos, not just between, but (for some) also within species. Keibel’s design adapted a plate by Wilhelm His and tables by Albert Oppel in order to go beyond the already controversial comparative plates of the Darwinist propagandist Ernst Haeckel. The project responded to local pressures, including intense concern with individual variation, but recruited internationally and mapped an embryological empire. Though theoretically inconclusive, the plates became standard laboratory tools and forged a network within which the Institut International d’Embryologie (today the International Society of Developmental Biologists) was founded in 1911. After World War I, experimentalists, led by Ross Harrison and Viktor Hamburger, and human embryologists, especially George Streeter at the Carnegie Department of Embryology, transformed Keibel’s complex, bulky tomes to suit their own contrasting demands. In developmental biology after World War II, normal stages—reduced to a few journal pages—helped domesticate model organisms. Staging systems had emerged from discussions that questioned the very possibility of assigning an embryo to a stage. The historical issues resonate today as developmental biologists work to improve and extend stage series, to make results from different laboratories easier to compare and to take individual variation into account. PMID:17183461
A history of normal plates, tables and stages in vertebrate embryology.

PubMed

Hopwood, Nick

2007-01-01

Developmental biology is today unimaginable without the normal stages that define standard divisions of development. This history of normal stages, and the related normal plates and normal tables, shows how these standards have shaped and been shaped by disciplinary change in vertebrate embryology. The article highlights the Normal Plates of the Development of the Vertebrates edited by the German anatomist Franz Keibel (16 volumes, 1897-1938). These were a major response to problems in the relations between ontogeny and phylogeny that amounted in practical terms to a crisis in staging embryos, not just between, but (for some) also within species. Keibel's design adapted a plate by Wilhelm His and tables by Albert Oppel in order to go beyond the already controversial comparative plates of the Darwinist propagandist Ernst Haeckel. The project responded to local pressures, including intense concern with individual variation, but recruited internationally and mapped an embryological empire. Though theoretically inconclusive, the plates became standard laboratory tools and forged a network within which the Institut International d'Embryologie (today the International Society of Developmental Biologists) was founded in 1911. After World War I, experimentalists, led by Ross Harrison and Viktor Hamburger, and human embryologists, especially George Streeter at the Carnegie Department of Embryology, transformed Keibel's complex, bulky tomes to suit their own contrasting demands. In developmental biology after World War II, normal stages-reduced to a few journal pages-helped domesticate model organisms. Staging systems had emerged from discussions that questioned the very possibility of assigning an embryo to a stage. The historical issues resonate today as developmental biologists work to improve and extend stage series, to make results from different laboratories easier to compare and to take individual variation into account.
The ontogeny of Robin sequence.

PubMed

Logjes, Robrecht J H; Breugem, Corstiaan C; Van Haaften, Gijs; Paes, Emma C; Sperber, Geoffrey H; van den Boogaard, Marie-José H; Farlie, Peter G

2018-04-25

The triad of micrognathia, glossoptosis, and concomitant airway obstruction defined as "Robin sequence" (RS) is caused by oropharyngeal developmental events constrained by a reduced stomadeal space. This sequence of abnormal embryonic development also results in an anatomical configuration that might predispose the fetus to a cleft palate. RS is heterogeneous and many different etiologies have been described including syndromic, RS-plus, and isolated forms. For an optimal diagnosis, subsequent treatment and prognosis, a thorough understanding of the embryology and pathogenesis is necessary. This manuscript provides an update about our current understanding of the development of the mandible, tongue, and palate and possible mechanisms involved in the development of RS. Additionally, we provide the reader with an up-to-date summary of the different etiologies of this phenotype and link this to the embryologic, developmental, and genetic mechanisms. © 2018 Wiley Periodicals, Inc.
CROSSOVERS BETWEEN EPIGENESIS AND EPIGENETICS. A MULTICENTER APPROACH TO THE HISTORY OF EPIGENETICS (1901-1975).

PubMed

Costa, Rossella; Frezza, Giulia

2014-01-01

The origin of epigenetics has been traditionally traced back to Conrad Hal Waddington's foundational work in 1940s. The aim of the present paper is to reveal a hidden history of epigenetics, by means of a multicenter approach. Our analysis shows that genetics and embryology in early XX century--far from being non-communicating vessels--shared similar questions, as epitomized by Thomas Hunt Morgan's works. Such questions were rooted in the theory of epigenesis and set the scene for the development of epigenetics. Since the 1950s, the contribution of key scientists (Mary Lyon and Eduardo Scarano), as well as the discussions at the international conference of Gif-sur-Yvette (1957) paved the way for three fundamental shifts of focus: 1. From the whole embryo to the gene; 2. From the gene to the complex extranuclear processes of development; 3. From cytoplasmic inheritance to the epigenetics mechanisms.
Early bases of modern embryology in Spain: microscopical anatomy and the introduction of cell theory and histology in their scientific and social European context.

PubMed

Marco-Cuellar, Roberto; Aréchaga, Juan

2009-01-01

We present a survey of the introduction and evolution of microscopy techniques in Spain, and the concepts and lines of research developed around this instrument, particularly in the field of Biomedical research. We cover in our article the long period from the XVII Century to the arrival of the great figure of Santiago Ramon y Cajal (1853-1934). We particularly want to mention many of the previously neglected pioneers who certainly paved the route for his discoveries and, we believe that without them, he would never have arrived to his important position in the annals of Biology and Medicine. The historical, scientific and social framework of that period also helped the approach to important biological concepts such as the cell and tissue, which are previous and essential ideas for a correct understanding of Development.
Embryology and histology education in North American dental schools: the Basic Science Survey Series.

PubMed

Burk, Dorothy T; Lee, Lisa M J; Lambert, H Wayne

2013-06-01

As part of the Basic Science Survey Series (BSSS) for Dentistry, members of the American Dental Education Association (ADEA) Anatomical Sciences Section surveyed faculty members teaching embryology and histology courses at North American dental schools. The survey was designed to assess, among other things, curriculum content, utilization of laboratories, use of computer-assisted instruction (CAI), and recent curricular changes. Responses were received from fifty-nine (88.1 percent) of the sixty-seven U.S. and Canadian dental schools. Findings suggest the following: 1) a trend toward combining courses is evident, though the integration was predominantly discipline-based; 2) embryology is rarely taught as a stand-alone course, as content is often covered in gross anatomy, oral histology, and/or in an integrated curriculum; 3) the number of contact hours in histology is decreasing; 4) a trend toward reduction in formal laboratory sessions, particularly in embryology, is ongoing; and 5) use of CAI tools, including virtual microscopy, in both embryology and histology has increased. Additionally, embryology and histology content topic emphasis is identified within this study. Data, derived from this study, may be useful to new instructors, curriculum and test construction committees, and colleagues in the anatomical sciences, especially when determining a foundational knowledge base.
Self-organized amniogenesis by human pluripotent stem cells in a biomimetic implantation-like niche

NASA Astrophysics Data System (ADS)

Shao, Yue; Taniguchi, Kenichiro; Gurdziel, Katherine; Townshend, Ryan F.; Xue, Xufeng; Yong, Koh Meng Aw; Sang, Jianming; Spence, Jason R.; Gumucio, Deborah L.; Fu, Jianping

2017-04-01

Amniogenesis--the development of amnion--is a critical developmental milestone for early human embryogenesis and successful pregnancy. However, human amniogenesis is poorly understood due to limited accessibility to peri-implantation embryos and a lack of in vitro models. Here we report an efficient biomaterial system to generate human amnion-like tissue in vitro through self-organized development of human pluripotent stem cells (hPSCs) in a bioengineered niche mimicking the in vivo implantation environment. We show that biophysical niche factors act as a switch to toggle hPSC self-renewal versus amniogenesis under self-renewal-permissive biochemical conditions. We identify a unique molecular signature of hPSC-derived amnion-like cells and show that endogenously activated BMP-SMAD signalling is required for the amnion-like tissue development by hPSCs. This study unveils the self-organizing and mechanosensitive nature of human amniogenesis and establishes the first hPSC-based model for investigating peri-implantation human amnion development, thereby helping advance human embryology and reproductive medicine.
[Beginning, formative power and intellect agent of Nicolò Leoniceno between the Arabic-Latin tradition and the rebirth of the Greek commentators].

PubMed

Hirai, Hiro

2007-01-01

The treatise On Formative Power (Venice, 1506) of Ferrara's emblematic medical humanist, Nicolò Leoniceno (1428-1524), is the one of the first embryological monographs of the Renaissance. It shows, at the same time, the continuity of medieval Arabo-Latin tradition and the new elements brought by Renaissance medical humanism, namely through the use of the ancient Greek commentators of Aristotle like Simplicius. Thus this treatise stands at the crossroad of these two currents. The present study analyses the range of Leoniceno's philosophical discussion, determines its exact sources and brings to light premises for the early modern development of the concept of formative force, which will end up in the theory of "plastic nature" at the heart of the Scientific Revolution.
Congenital coronary artery anomalies: a bridge from embryology to anatomy and pathophysiology--a position statement of the development, anatomy, and pathology ESC Working Group.

PubMed

Pérez-Pomares, José María; de la Pompa, José Luis; Franco, Diego; Henderson, Deborah; Ho, Siew Yen; Houyel, Lucile; Kelly, Robert G; Sedmera, David; Sheppard, Mary; Sperling, Silke; Thiene, Gaetano; van den Hoff, Maurice; Basso, Cristina

2016-02-01

Congenital coronary artery anomalies are of major significance in clinical cardiology and cardiac surgery due to their association with myocardial ischaemia and sudden death. Such anomalies are detectable by imaging modalities and, according to various definitions, their prevalence ranges from 0.21 to 5.79%. This consensus document from the Development, Anatomy and Pathology Working Group of the European Society of Cardiology aims to provide: (i) a definition of normality that refers to essential anatomical and embryological features of coronary vessels, based on the integrated analysis of studies of normal and abnormal coronary embryogenesis and pathophysiology; (ii) an animal model-based systematic survey of the molecular and cellular mechanisms that regulate coronary blood vessel development; (iii) an organization of the wide spectrum of coronary artery anomalies, according to a comprehensive anatomical and embryological classification scheme; (iv) current knowledge of the pathophysiological mechanisms underlying symptoms and signs of coronary artery anomalies, with diagnostic and therapeutic implications. This document identifies the mosaic-like embryonic development of the coronary vascular system, as coronary cell types differentiate from multiple cell sources through an intricate network of molecular signals and haemodynamic cues, as the necessary framework for understanding the complex spectrum of coronary artery anomalies observed in human patients. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.
A Review of the Relevant Embryology, Pathohistology, and Anatomy of the Left Atrial Appendage for the Invasive Cardiac Electrophysiologist

PubMed Central

DeSimone, Christopher V.; Gaba, Prakriti; Tri, Jason; Syed, Faisal; Noheria, Amit; Asirvatham, Samuel J.

2016-01-01

The three-dimensional morphology of the left atrial appendage provides the substrate for thrombus generation, and is a harbinger for embolic material due to its direct connection to the left-sided circulation. Appreciating the development of the appendage from mesodermal layer to its adult form provides the basis to improve exclusion from the atrial circulation, and thereby can lead to a significant reduction in stroke risk. This process also provides insight into the role of the left atrial appendage as an endocrine organ, its involvement in fluid homeostasis, and its connection to the autonomic nervous system. Knowledge of the surrounding structural arrangement is critical to identify landmarks from both an endocardial and epicardial perspective to improve targeted device placement. Furthermore, correlation of the left atrial appendage body, neck, and ostium to the surrounding anatomy can also improve both procedural efficacy and safety. In addition, a working knowledge of the regional anatomy adds a prudent degree of awareness for procedural complications, and allows for early identification and timely intervention as these situations arise. A detailed understanding of the left atrial appendage embryology, histology, and gross anatomy is imperative to identify the correct device and approach for each individual patient. In addition, this increased awareness can identify areas that are in need of further innovation, and thus provide the ability to adapt and refine existing technologies to overcome pitfalls currently facing catheter-based approaches. PMID:27087889
Embryoids, organoids and gastruloids: new approaches to understanding embryogenesis

PubMed Central

2017-01-01

ABSTRACT Cells have an intrinsic ability to self-assemble and self-organize into complex and functional tissues and organs. By taking advantage of this ability, embryoids, organoids and gastruloids have recently been generated in vitro, providing a unique opportunity to explore complex embryological events in a detailed and highly quantitative manner. Here, we examine how such approaches are being used to answer fundamental questions in embryology, such as how cells self-organize and assemble, how the embryo breaks symmetry, and what controls timing and size in development. We also highlight how further improvements to these exciting technologies, based on the development of quantitative platforms to precisely follow and measure subcellular and molecular events, are paving the way for a more complete understanding of the complex events that help build the human embryo. PMID:28292844
A burgeoning science of embryological genetics demands a modern ethics.

PubMed

Edwards, R G

2007-09-01

This brief article discusses the nature of recent scientific advances in reproductive biomedicine and genetics, their moral implications and their effects on society. The pace of research has amplified exponentially, leading society into situations incomprehended by our ancestors. Early studies on reproductive biology in animals, and clinical methods such as artificial insemination by donor spermatozoa, were introduced several centuries ago and led to prolonged ethical disagreements. The 20th century witnessed the introduction of controlled ovulation in laboratory animals, the fertilization of the oocyte and preimplantation embryology in mammalian species. The second half of this century produced an avalanche of knowledge on genetics, developmental biology, the fertilization of the human oocyte in vitro, test-tube babies, preimplantation genetic diagnosis, designer babies, stem cells and a deeper understanding of molecular differentiation in the human embryo. The ethical and legal aspects of these items have led to intense debates on their rights and wrongs. The future may have even more bizarre possibilities such as producing medicines in cow's milk or trees and delaying death for many years.
A new dynamic 3D virtual methodology for teaching the mechanics of atrial septation as seen in the human heart.

PubMed

Schleich, Jean-Marc; Dillenseger, Jean-Louis; Houyel, Lucile; Almange, Claude; Anderson, Robert H

2009-01-01

Learning embryology remains difficult, since it requires understanding of many complex phenomena. The temporal evolution of developmental events has classically been illustrated using cartoons, which create difficulty in linking spatial and temporal aspects, such correlation being the keystone of descriptive embryology. We synthesized the bibliographic data from recent studies of atrial septal development. On the basis of this synthesis, consensus on the stages of atrial septation as seen in the human heart has been reached by a group of experts in cardiac embryology and pediatric cardiology. This has permitted the preparation of three-dimensional (3D) computer graphic objects for the anatomical components involved in the different stages of normal human atrial septation. We have provided a virtual guide to the process of normal atrial septation, the animation providing an appreciation of the temporal and morphologic events necessary to separate the systemic and pulmonary venous returns. We have shown that our animations of normal human atrial septation increase significantly the teaching of the complex developmental processes involved, and provide a new dynamic for the process of learning.
To QC or not to QC: the key to a consistent laboratory?

PubMed

Lane, Michelle; Mitchell, Megan; Cashman, Kara S; Feil, Deanne; Wakefield, Sarah; Zander-Fox, Deirdre L

2008-01-01

A limiting factor in every embryology laboratory is its capacity to grow 'normal' embryos. In human in vitro fertilisation (IVF), there is considerable awareness that the environment of the laboratory itself can alter the quality of the embryos produced and the industry as a whole has moved towards the implementation of auditable quality management systems. Furthermore, in some countries, such as Australia, an established quality management system is mandatory for clinical IVF practice, but such systems are less frequently found in other embryology laboratories. Although the same challenges of supporting consistent and repeatable embryo development are paramount to success in all embryology laboratories, it could be argued that they are more important in a research setting where often the measured outcomes are at an intracellular or molecular level. In the present review, we have outlined the role and importance of quality control and quality assurance systems in any embryo laboratory and have highlighted examples of how simple monitoring can provide consistency and avoid the induction of artefacts, irrespective of the laboratory's purpose, function or species involved.

Effects of temperature on survival and development of early life stage Pacific and western brook lampreys

USGS Publications Warehouse

Meeuwig, M.H.; Bayer, J.M.; Seelye, J.G.

2005-01-01

We examined the effects of temperature (10, 14, 18, and 22??C) on survival and development of Pacific lampreys Lampetra tridentata and western brook lampreys L. richardsoni during embryological and early larval stages. The temperature for zero development was estimated for each species, and the response to temperature was measured as the proportion of individuals surviving to hatch, surviving to the larval stage, and exhibiting abnormalities at the larval stage (i.e., malformations of the body). The estimated temperature for zero development was 4.850C for Pacific lampreys and 4.97??C for western brook lampreys. Survival was greatest at 18??C, followed by 14, 10, and 22??C, significant differences being observed between 22??C and the other temperatures. Overall survival was significantly greater for western brook lampreys than for Pacific lampreys; however, the overall difference in proportion of individuals surviving was only 0.02. Overall survival significantly decreased from the time of hatch (proportion surviving = 0.85) to the larval stage (0.82; i.e., during the free-embryo stage). The proportion of individuals exhibiting abnormalities at the larval stage was greatest at 22??C, followed by 18, 10, and 14??C, significant differences being observed between 22??C and the other temperatures. These data provide baseline information on the thermal requirements of early life stage Pacific and western brook lampreys and will aid in assessment and prediction of suitable spawning and rearing habitats for these species.
Embryological evidence for a possible polyphyletic origin of the recent amphibians.

PubMed

Nieuwkoop, P D; Sutasurya, L A

1976-02-01

The markedly different mode of mesoderm formation in anuran and urodelan amphibians (which is related to the early double-layered nature of the anuran blastula wall in contrast to its single-layered nature in the urodeles), but particularly the fundamentally different place and mode of origin of the primordial germ cells in the two groups of amphibians, strongly pleads in favour of a very ancient bifurcation in the phylogenetic history of the two groups, even suggesting a polyphyletic origin from different ancestral fishes.
The first whole transcriptomic exploration of pre-oviposited early chicken embryos using single and bulked embryonic RNA-sequencing.

PubMed

Hwang, Young Sun; Seo, Minseok; Choi, Hee Jung; Kim, Sang Kyung; Kim, Heebal; Han, Jae Yong

2018-04-01

The chicken is a valuable model organism, especially in evolutionary and embryology research because its embryonic development occurs in the egg. However, despite its scientific importance, no transcriptome data have been generated for deciphering the early developmental stages of the chicken because of practical and technical constraints in accessing pre-oviposited embryos. Here, we determine the entire transcriptome of pre-oviposited avian embryos, including oocyte, zygote, and intrauterine embryos from Eyal-giladi and Kochav stage I (EGK.I) to EGK.X collected using a noninvasive approach for the first time. We also compare RNA-sequencing data obtained using a bulked embryo sequencing and single embryo/cell sequencing technique. The raw sequencing data were preprocessed with two genome builds, Galgal4 and Galgal5, and the expression of 17,108 and 26,102 genes was quantified in the respective builds. There were some differences between the two techniques, as well as between the two genome builds, and these were affected by the emergence of long intergenic noncoding RNA annotations. The first transcriptome datasets of pre-oviposited early chicken embryos based on bulked and single embryo sequencing techniques will serve as a valuable resource for investigating early avian embryogenesis, for comparative studies among vertebrates, and for novel gene annotation in the chicken genome.
Applications of Tol2 Transposon-Mediated Gene Transfer for Stable Integration and Conditional Expression of Electroporated Genes in Chicken Embryos

NASA Astrophysics Data System (ADS)

Sato, Yuki; Takahashi, Yoshiko

Because of the high accessibility to developing embryos, avian embryos (chicken and quail) have long been used as a good model animal to study embryogenesis in vertebrates, especially amniotes (reviewed in Wolpert, 2004). The techniques used for “classical” avian embryology included tissue transplantations, tissue ablations, and cell-labeling by vital dye. At the end of the last century, the in ovo electropora tion technique was developed by Nakamura and his colleagues, and this modern method opened a way to study the roles of developmental genes directly in living embryos (Funahashi et al., 1999) reviewed in (Nakamura et al., 2004; Yasuda et al., 2000; Yasugi and Nakamura, 2000). This powerful technique allows us to introduce genes (DNA, RNA, morpholino) into embryos in a tissue-specific way by targeting a restricted area of embryonic tissues. Thus, the electroporation technique using chickens has provided numerous novel insights into the understanding of early development in vertebrates, making the chicken a unique model animal.
Periods and stages of the prenatal development of the domestic cat.

PubMed

Knospe, C

2002-02-01

Twenty-two stages of the prenatal development of the domestic cat are described for intraspecies comparison in embryological studies. These are assigned to the 15 embryonal periods based on the Nomina Embryologica Veterinaria to make the interspecies comparison possible.
Management of acute lower extremity deep venous thrombosis in a patient with duplicated inferior vena cava and contraindication to anticoagulation: case and review of the literature

PubMed Central

Patel, Shrinil; Cheema, Anmol; Karawadia, Tejas; Carson, Michael

2018-01-01

Duplication of the inferior vena cava (DIVC) is an uncommon embryological anatomic phenomenon. We report a 63-year-old woman with extensive right leg deep vein thrombosis who required an IVC filter due to contraindications for anticoagulation, but was found to have DIVC which required the placement of two IVC filters with good result. This report will review and summarise past reports of DIVC management to provide a guide for future clinicians, and review the embryological development, diagnosis and IVC filter placement options as they are based on the type of anatomic malformation encountered. PMID:29866665
The grass isn't always greener: The effects of cannabis on embryological development.

PubMed

Friedrich, Joseph; Khatib, Dara; Parsa, Keon; Santopietro, Ariana; Gallicano, G Ian

2016-09-29

With the increasing publicity of marijuana due to recent legislation, it is pertinent that the effects of fetal exposure to the drug are assessed. While in utero cannabis exposure has been associated with early pregnancy failure, birth defects and developmental delay, the mechanisms of such outcomes are largely unexplained. Furthermore, the use of cannabinoids in cancer treatment via growth inhibition and apoptosis may indicate how cannabis exposure likely harms a growing fetus. Cannabinoid signaling is required for proper pre-implantation development, embryo transport to the uterus, and uterine receptivity during implantation. In post-implantation development, cannabinoid signaling functions in a multitude of pathways, including, but not limited to, folic acid, VEGF, PCNA, MAPK/ERK, and BDNF. Disrupting the normal activity of these pathways can significantly alter many vital in utero processes, including angiogenesis, cellular replication, tissue differentiation, and neural cognitive development. This paper aims to demonstrate the effects of cannabis exposure on a developing embryo in order to provide a molecular explanation for the adverse outcomes associated with cannabis use during pregnancy.
Contemporary issues in the regulation of artificial reproduction and embryology in the UK.

PubMed

Garwood-Gowers, Austen

2004-01-01

The Human Fertilisation and Embryology Act 1990 was one of the most comprehensive and flexible vehicles for regulation of artificial reproduction and embryology of its area. However, its serviceability has recently been brought into question by both the materialisation of unforeseen dilemmas and the response of legal actors to these dilemma's which has often been ethically and democratically deficient. Nowhere is this better demonstrated than in the reproach of the regulatory authority and judiciary to the use pre-implantation genetic diagnosis and cloning by cell nuclear replacement.
Using embryology screencasts: a useful addition to the student learning experience?

PubMed

Evans, Darrell J R

2011-01-01

Although podcasting has been a well used resource format in the last few years as a way of improving the student learning experience, the inclusion of enhanced audiovisual formats such as screencasts has been less used, despite the advantage that they work well for both visual and auditory learners. This study examines the use of and student reaction to a set of screencasts introduced to accompany embryology lectures within a second year module at Brighton and Sussex Medical School. Five mini-lecture screencasts and one review quiz screencast were produced as digital recordings of computer screen output with audio narration and released to students via the managed learning environment (MLE). Analysis of server log information from the MLE showed that the screencasts were accessed by many of the students in the cohort, although the exact numbers were variable depending on the screencast. Students accessed screencasts at different times of the day and over the whole of the access period, although maximum downloads were predictably recorded leading up to the written examination. Quantitative and qualitative feedback demonstrated that most students viewed the screencasts favorably in terms of usefulness to their learning, and end-of-module written examination scores suggest that the screencasts may have had a positive effect on student outcome when compared with previous student attainment. Overall, the development of a series of embryology screencasts to accompany embryology lecture sessions appears to be a useful addition to learning for most students and not simply an innovation that checks the box of "technology engagement." Copyright © 2011 American Association of Anatomists.
Prenatal Influences on the Brain.

ERIC Educational Resources Information Center

Eliot, Lise

2002-01-01

Gives an overview of embryology and prenatal brain, sensory, and motor development. Includes discussion of maternal nutrition, chemical exposure, prenatal drug and alcohol hazards, cigarette smoking, and some causes of neural tube defects and premature birth. (Author/KB)
Teaching Embryology without Lectures and without Traditional Laboratories--An Adventure in Innovation.

ERIC Educational Resources Information Center

Heady, Judith E.

1993-01-01

Describes problems with teaching embryology in the traditional manner. Presents a new approach where students prepare presentations, questions, and discussion topics. During laboratory periods, students conducted their own long-term research projects. (PR)
For the Classroom: The Sea Urchin Fertilization and Embryology Lab.

ERIC Educational Resources Information Center

Brevoort, Douglas

1984-01-01

The sea urchin provides an ideal embryology laboratory because it is visually representative of the fertilization process in higher animals. Procedures for conducting such a laboratory (including methods for securing specimens) are provided. (JN)
The mandible and its foramen: anatomy, anthropology, embryology and resulting clinical implications.

PubMed

Lipski, M; Tomaszewska, I M; Lipska, W; Lis, G J; Tomaszewski, K A

2013-11-01

The aim of this paper is to summarise the knowledge about the anatomy, embryology and anthropology of the mandible and the mandibular foramen and also to highlight the most important clinical implications of the current studies regarding anaesthesia performed in the region of the mandible. An electronic journal search was undertaken to identify all the relevant studies published in English. The search included MEDLINE and EMBASE databases and years from 1950 to 2012. The subject search used a combination of controlled vocabulary and free text based on the search strategy for MEDLINE using key words: 'mandible', 'mandibular', 'foramen', 'anatomy', 'embryology', 'anthropology', and 'mental'. The reference lists of all the relevant studies and existing reviews were screened for additional relevant publications. Basing on relevant manuscripts, this short review about the anatomy, embryology and anthropology of the mandible and the mandibular foramen was written.
Bone development in laboratory mammals used in developmental toxicity studies.

PubMed

DeSesso, John M; Scialli, Anthony R

2018-06-19

Evaluation of the skeleton in laboratory animals is a standard component of developmental toxicology testing. Standard methods of performing the evaluation have been established, and modification of the evaluation using imaging technologies is under development. The embryology of the rodent, rabbit, and primate skeleton has been characterized in detail and summarized herein. The rich literature on variations and malformations in skeletal development that can occur in the offspring of normal animals and animals exposed to test articles in toxicology studies is reviewed. These perturbations of skeletal development include ossification delays, alterations in number, shape, and size of ossification centers, and alterations in numbers of ribs and vertebrae. Because the skeleton is undergoing developmental changes at the time fetuses are evaluated in most study designs, transient delays in development can produce apparent findings of abnormal skeletal structure. The determination of whether a finding represents a permanent change in embryo development with adverse consequences for the organism is important in study interpretation. Knowledge of embryological processes and schedules can assist in interpretation of skeletal findings. © 2018 The Authors. Birth Defects Research Published by Wiley Periodicals, Inc.
Bone up: craniomandibular development and hard-tissue biomineralization in neonate mice.

PubMed

Thompson, Khari D; Weiss-Bilka, Holly E; McGough, Elizabeth B; Ravosa, Matthew J

2017-10-01

The presence of regional variation in the osteogenic abilities of cranial bones underscores the fact that the mechanobiology of the mammalian skull is more complex than previously recognized. However, the relationship between patterns of cranial bone formation and biomineralization remains incompletely understood. In four strains of mice, micro-computed tomography was used to measure tissue mineral density during perinatal development in three skull regions (calvarium, basicranium, mandible) noted for variation in loading environment, embryological origin, and ossification mode. Biomineralization levels increased during perinatal ontogeny in the mandible and calvarium, but did not increase in the basicranium. Tissue mineral density levels also varied intracranially, with density in the mandible being highest, in the basicranium intermediate, and in the calvarium lowest. Perinatal increases in, and elevated levels of, mandibular biomineralization appear related to the impending postweaning need to resist elevated masticatory stresses. Similarly, perinatal increases in calvarial biomineralization may be linked to ongoing brain expansion, which is known to stimulate sutural bone formation in this region. The lack of perinatal increase in basicranial biomineralization could be a result of earlier developmental maturity in the cranial base relative to other skull regions due to its role in supporting the brain's mass throughout ontogeny. These results suggest that biomineralization levels and age-related trajectories throughout the skull are influenced by the functional environment and ontogenetic processes affecting each region, e.g., onset of masticatory loads in the mandible, whereas variation in embryology and ossification mode may only have secondary effects on patterns of biomineralization. Knowledge of perinatal variation in tissue mineral density, and of normal cranial bone formation early in development, may benefit clinical therapies aiming to correct developmental defects and traumatic injuries in the skull, and more generally characterize loading environments and skeletal adaptations in mammals by highlighting the need for multi-level analyses for evaluating functional performance of cranial bone. Copyright © 2017 Elsevier GmbH. All rights reserved.
A new dynamic 3D virtual methodology for teaching the mechanics of atrial septation as seen in the human heart

PubMed Central

Schleich, Jean-Marc; Dillenseger, Jean-Louis; Houyel, Lucile; Almange, Claude; Anderson, Robert H.

2009-01-01

Background Learning embryology remains difficult, since it requires understanding of many complex phenomena. The temporal evolution of developmental events has classically been illustrated using cartoons, which create difficulty in linking spatial and temporal aspects, such correlation being the keystone of descriptive embryology. Methods We synthesized the bibliographic data from recent studies of atrial septal development. On the basis of this synthesis, consensus on the stages of atrial septation as seen in the human heart has been reached by a group of experts in cardiac embryology and paediatric cardiology. This has permitted the preparation of three-dimensional (3-D) computer graphic objects for the anatomical components involved in the different stages of normal human atrial septation. Results We have provided a virtual guide to the process of normal atrial septation, the animation providing an appreciation of the temporal and morphologic events necessary to separate the systemic and pulmonary venous returns. Conclusion We have shown that our animations of normal human atrial septation increase significantly the teaching of the complex developmental processes involved, and provide a new dynamic for the process of learning. PMID:19363807
Failure of vincristine induce twinning

NASA Technical Reports Server (NTRS)

Binder, M.

1984-01-01

Mammalian ova do not contain axes of symmetry from which are derived embryonic axes of symmetry. Mammalian axis determination is an early embryologic event occurring at about the time that monozygous twinning in mice. (Kaufma MH & O'Shea KS, 1978, Nature 276:707) and an attempt was made to reproduce their work in several strains of mice. Over 3200 embryos were examined without any twins being found. To rule out the possibility that vincristine caused twinning plus some lethal malformation (with subsequent resorption of the embryo) the embryos were examined 36-60 hours after vincristine treatment.
First branchial cleft fistula presenting with internal opening on the Eustachian tube: Illustrated cases and literature review.

PubMed

Liu, Yuhe; Li, Tiancheng; Xue, Junfang; Jia, Jun; Xiao, Shuifang; Zhao, Enmin

2012-05-01

Two cases of first branchial cleft fistula with internal opening on the Eustachian tube are reported and the diagnosis, management and embryological hypothesis are discussed. Retrospective study and review of the literature. Both patients were young boys with first branchial cleft anomaly clearly identified by computed tomography fistulography scan and direct Methylene Blue dye injection. In both cases, surgical removal revealed a fistula with internal opening located on the Eustachian tube near the nasopharynx. The main embryological theories and classification are reviewed. A connection between the theories of first branchial apparatus development and the classification by Work might explain the reported clinical association. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Principles and management of adrenal cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Javadpour, N.

1987-01-01

This book provides information on adrenal diseases of latest developments and guides the clinicians in the care of their patients. The book is divided into two parts. The first section gives an overview of the embryology, anatomy, physiology, markers, pathology, imaging and the current progress in the field. The second edition covers specific diseases of the adrenal cortex and medulla. The increasingly significant roles played by steroids, catecholamines, blockers, computed tomography and magnetic resonance are elucidated and discussed. The contents include: Overview of progress; current problems, and perspectives - embryology anatomy, physiology, and biologic markers; pathology; advances in diagnosis; imagingmore » techniques; adrenal disorders in childhood; primary aldosteronism; Cushing's syndrome; carcinoma; pheochromocytoma; neuroblastoma; metastatic disease; surgical management; and subject index.« less
Pathology of cloaca anomalies with case correlation.

PubMed

Gupta, Anita; Bischoff, Andrea

2016-04-01

During the fourth week of human embryo development, a transient common channel known as a cloaca is formed from which three cavities with three external orifices arises. Cloaca anomalies occur when there is failure of separation of the rectum, vagina, and urethra channel resulting in a single drain into the perineum. In our previous institutional studies, Runck et al. compared human and mouse cloaca development and found early mis-patterning of the embryonic cloaca deranged hedgehog and bone morphogenetic proteins (BMP) signaling. Also, our group reported the embryological correlation of the epithelial and stromal histology found in step sections of the common channel in 14 cloaca malformations in humans. In this review, we present the pathology of a 4-year-old female with a cloaca and VACTERL complex, and summarize our current knowledge of cloaca pathology. Furthermore, we suggest that careful pathological examination of cloaca specimens in conjunction with surgical orientation may result in a better understanding of the etiology of this condition. Published by Elsevier Inc.

Homology of the reptilian coracoid and a reappraisal of the evolution and development of the amniote pectoral apparatus

PubMed Central

Vickaryous, Matthew K; Hall, Brian K

2006-01-01

As in monotreme mammals, the pectoral apparatus of basal (fossil) amniotes includes two coracoid elements, the procoracoid and metacoracoid. Among extant reptiles the metacoracoid has long been assumed lost; this notion is herein challenged. A comprehensive review of data from numerous sources, including the fossil record, experimental embryology, genetic manipulations and an analysis of morphology at the level cell condensations, supports the conclusion that the metacoracoid gives rise to the majority of the reptilian coracoid. By contrast, the reptilian procoracoid remains as a rudiment that is incorporated as a process of the (meta)coracoid and/or the glenoid region of the scapula early during development, prior to skeletogenesis. Application of this integrated approach corroborates and enhances previous work describing the evolution of the pectoral apparatus in mammals. A revised scenario of amniote coracoid evolution is presented emphasizing the importance of considering cell condensations when evaluating the homology of a skeletal complex. PMID:16533312
Isolated Anomalous Origin of Left Pulmonary Artery From the Descending Aorta: An Embryologic Ambiguity.

PubMed

Gnanappa, Ganesh Kumar; Laohachai, Karina; Orr, Yishay; Ayer, Julian

2016-11-01

Anomalous origin of a branch pulmonary artery from the aorta is a rare malformation, accounting for 0.12% of all congenital heart defects. Anomalous origin of the left pulmonary artery from the aorta (ALPA) constitutes a small proportion of these cases. ALPA has been reported to arise from the ascending aorta with various embryologic postulates. We report a case of isolated ALPA arising from the descending aorta in association with a patent ductus arteriosus, to emphasize its embryologic ambiguity. Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
Embryologic and anatomic basis of inguinal herniorrhaphy.

PubMed

Skandalakis, J E; Colborn, G L; Androulakis, J A; Skandalakis, L J; Pemberton, L B

1993-08-01

The embryology and surgical anatomy of the inguinal area is presented with emphasis on embryologic and anatomic entities related to surgery. We have presented the factors, such as patent processus vaginalis and defective posterior wall of the inguinal canal, that may be responsible for the genesis of congenital inguinofemoral herniation. These, together with impaired collagen synthesis and trauma, are responsible for the formation of the acquired inguinofemoral hernia. Still, we do not have all the answers for an ideal repair. Despite the latest successes in repair, we, to paraphrase Ritsos, are awaiting the triumphant return of Theseus.
Developing the Digital Kyoto Collection in Education and Research.

PubMed

Hill, Mark Anthony

2018-04-16

The Kyoto embryo collection was begun in 1961 by Dr. Hideo Nishimura. The collection has been continuously developed and currently contains over 44,000 human normal and abnormal specimens. Beginning online in 1997, the internet provided an opportunity to make embryos from the collection widely available for research and educational purposes (http://tiny.cc/Embryo). These embryonic development resources have been continuously published and available from that time until today. Published in Japanese as an Atlas of Embryonic Development. Published online as the Kyoto Human Embryo Visualization Project (http://atlas.cac.med.kyoto-u.ac.jp) and also as the Human Embryo Atlas (http://tiny.cc/Human_Embryo_Atlas). Published now electronically as a digital eBook (http://tiny.cc/Kyoto_Collection_eBook). This new digital format allows incorporation of whole embryo and histology manipulable images, labels, and a linked glossary. New imaging modalities of magnetic resonance imaging (MRI) and episcopic fluorescence image capture (EFIC) can also be easily displayed as animations. For research, the collection specimens and histological sections have been extensively studied and published in several hundred papers, discussed here and elsewhere in this special edition. I will also describe how the Kyoto collection will now form a major partner of a new international embryology research group, the Digital Embryology Consortium (https://human-embryology.org). The digital Kyoto collection will be made available for remote researcher access, analysis, and comparison with other collections allowing new research and educational applications. This work was presented at the 40th Anniversary Commemoration Symposium of the Congenital Anomaly Research Center, Graduate School of Medicine, Kyoto University, Japan, November, 2015. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.
Embryological Development: Evolutionary History, Genetic Bias, and Cellular Environment Control the Flow of Developmental Events. Part I.

ERIC Educational Resources Information Center

Caplan, Arnold I.

1981-01-01

Describes development of the limb and various interactions necessary for the expression of its unique form and phenotypes to uncover the hierarchical controlling steps in the development process for the potential of avoiding abnormal events and manipulating what might be detrimental genetic events into a normal sequence. (Author/SK)
Esophageal duplication and congenital esophageal stenosis.

PubMed

Trappey, A Francois; Hirose, Shinjiro

2017-04-01

Esophageal duplication and congenital esophageal stenosis (CES) may represent diseases with common embryologic etiologies, namely, faulty tracheoesophageal separation and differentiation. Here, we will re-enforce definitions for these diseases as well as review their embryology, diagnosis, and treatment. Copyright © 2017. Published by Elsevier Inc.
Craniofacial duplication (diprosopus).

PubMed

Turpin, I M; Furnas, D W; Amlie, R N

1981-02-01

No congenital malformation in infants is more profound than anterior craniofacial duplication. The precise term for this rare anomaly is diprosopus, referring to a fetus with a single trunk, normal limbs, and varying degrees of facial duplication. A search of the world literature produced only 16 cases of diprosopus since 1864. Despite the rarity of this anomaly, three such infants were born in the Southern California area during the past year, making this the largest reported series to date. The three infants were born with two distinctly formed faces. Each had four separate eyes, two mouths, two noses, and two ears with a primitive ear or sinus tract at the plane of fusion. In addition, multiple congenital aberrations existed which involved a variety of internal organs. The pathogenesis of diprosopus is not well understood, but environmental stress early in embryologic development has been suggested as a possible factor. The apparent mechanism is a slowing of pregastrulation oxidation with resultant focal developmental arrests.
Jelena Krmpotić-Nemanić (1921-2008): contributions to human neuroanatomy.

PubMed

Judas, Milos; Petanjek, Zdravko; Kostović, Ivica

2011-01-01

Jelena Krmpotić-Nemanić (1921-2008) was a world-famous anatomist, internationally distinguished otolaryngologist, a member of the Croatian Academy of Sciences & Arts and appreciated professor at the School of Medicine University of Zagreb. The founding influence in her scientific career came from her mentor Drago Perovid who was a student of Ferdinand Hochstetter, the leading authority in the field of human developmental neuroanatomy and embryology. Such an influence was obviously important in early shaping of the research agenda of Jelena Krmpotić-Nemanić, and it remains important in a long series of studies on developing human telencephalon initiated by Ivica Kostović and his collaborators - with an always present and active support of Jelena Krmpotić-Nemanić. The aim of this mini review is to briefly describe her numerous contributions to the anatomy of the human peripheral and central nervous system.
Concepts of Cell Lineage in Mammalian Embryos.

PubMed

Papaioannou, Virginia E

2016-01-01

Cell lineage is the framework for understanding cellular diversity, stability of differentiation, and its relationship to pluripotency. The special condition of in utero development in mammals has presented challenges to developmental biologists in tracing cell lineages but modern imaging and cell marking techniques have allowed the gradual elucidation of lineage relationships. Early experimental embryology approaches had limited resolution and relied of suboptimal cell markers and considerable disturbance to the embryos. Transgenic technology introduced genetic markers, particularly fluorescent proteins that, combined with sophisticated imaging modalities, greatly increase resolution and allow clonal analysis within lineages. The concept of cell lineage has also undergone evolution as it became possible to trace the lineage of cells based not only on their physical location or attributes but also on their gene expression pattern, thus opening up mechanistic lines of investigation into the determinants of cell lineage. © 2016 Elsevier Inc. All rights reserved.
Pectus excavatum: history, hypotheses and treatment options

PubMed Central

Brochhausen, Christoph; Turial, Salmai; Müller, Felix K.P.; Schmitt, Volker H.; Coerdt, Wiltrud; Wihlm, Jean-Marie; Schier, Felix; Kirkpatrick, C. James

2012-01-01

Pectus excavatum and pectus carinatum represent the most frequent chest wall deformations. However, the pathogenesis is still poorly understood and research results remain inconsistent. To focus on the recent state of knowledge, we summarize and critically discuss the pathological concepts based on the history of these entities, beginning with the first description in the sixteenth century. Based on the early clinical descriptions, we review and discuss the different pathogenetic hypotheses. To open new perspectives for the potential pathomechanisms, the embryonic and foetal development of the ribs and the sternum is highlighted following the understanding that the origin of these deformities is given by the disruption in the maturation of the parasternal region. In the second, different therapeutical techniques are highlighted and based on the pathogenetic hypotheses and the embryological knowledge potential new biomaterial-based perspectives with interesting insights for tissue engineering-based treatment options are presented. PMID:22394989
Time to take human embryo culture seriously.

PubMed

Sunde, Arne; Brison, Daniel; Dumoulin, John; Harper, Joyce; Lundin, Kersti; Magli, M Cristina; Van den Abbeel, Etienne; Veiga, Anna

2016-10-01

Is it important that end-users know the composition of human embryo culture media? We argue that there is as strong case for full transparency concerning the composition of embryo culture media intended for human use. Published data suggest that the composition of embryo culture media may influence the phenotype of the offspring. A review of the literature was carried out. Data concerning the potential effects on embryo development of culture media were assessed and recommendations for users made. The safety of ART procedures, especially with respect to the health of the offspring, is of major importance. There are reports from the literature indicating a possible effect of culture conditions, including culture media, on embryo and fetal development. Since the introduction of commercially available culture media, there has been a rapid development of different formulations, often not fully documented, disclosed or justified. There is now evidence that the environment the early embryo is exposed to can cause reprogramming of embryonic growth leading to alterations in fetal growth trajectory, birthweight, childhood growth and long-term disease including Type II diabetes and cardiovascular problems. The mechanism for this is likely to be epigenetic changes during the preimplantation period of development. In the present paper the ESHRE working group on culture media summarizes the present knowledge of potential effects on embryo development related to culture media, and makes recommendations. There is still a need for large prospective randomized trials to further elucidate the link between the composition of embryo culture media used and the phenotype of the offspring. We do not presently know if the phenotypic changes induced by in vitro embryo culture represent a problem for long-term health of the offspring. Published data indicate that there is a strong case for demanding full transparency concerning the compositions of and the scientific rationale behind the composition of embryo culture media. This work was funded by The European Society for Human Reproduction and Embryology. No competing interests to declare. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Ocean acidification has little effect on developmental thermal windows of echinoderms from Antarctica to the tropics.

PubMed

Karelitz, Sam E; Uthicke, Sven; Foo, Shawna A; Barker, Mike F; Byrne, Maria; Pecorino, Danilo; Lamare, Miles D

2017-02-01

As the ocean warms, thermal tolerance of developmental stages may be a key driver of changes in the geographical distributions and abundance of marine invertebrates. Additional stressors such as ocean acidification may influence developmental thermal windows and are therefore important considerations for predicting distributions of species under climate change scenarios. The effects of reduced seawater pH on the thermal windows of fertilization, embryology and larval morphology were examined using five echinoderm species: two polar (Sterechinus neumayeri and Odontaster validus), two temperate (Fellaster zelandiae and Patiriella regularis) and one tropical (Arachnoides placenta). Responses were examined across 12-13 temperatures ranging from -1.1 °C to 5.7 °C (S. neumayeri), -0.5 °C to 10.7 °C (O. validus), 5.8 °C to 27 °C (F. zelandiae), 6.0 °C to 27.1 °C (P. regularis) and 13.9 °C to 34.8 °C (A. placenta) under present-day and near-future (2100+) ocean acidification conditions (-0.3 pH units) and for three important early developmental stages 1) fertilization, 2) embryo (prehatching) and 3) larval development. Thermal windows for fertilization were broad and were not influenced by a pH decrease. Embryological development was less thermotolerant. For O. validus, P. regularis and A. placenta, low pH reduced normal development, albeit with no effect on thermal windows. Larval development in all five species was affected by both temperature and pH; however, thermal tolerance was not reduced by pH. Results of this study suggest that in terms of fertilization and development, temperature will remain as the most important factor influencing species' latitudinal distributions as the ocean continues to warm and decrease in pH, and that there is little evidence of a synergistic effect of temperature and ocean acidification on the thermal control of species ranges. © 2016 John Wiley & Sons Ltd.
Zebrafish embryology and cartilage staining protocols for high school students.

PubMed

Emran, Farida; Brooks, Jacqueline M; Zimmerman, Steven R; Johnson, Susan L; Lue, Robert A

2009-06-01

The Life Sciences-Howard Hughes Medical Institute Outreach Program at Harvard University supports high school science education by offering an on-campus program for students and their teachers to participate in investigative, hands-on laboratory sessions. The outreach program has recently designed and launched a successful zebrafish embryology protocol that we present here. The main objectives of this protocol are to introduce students to zebrafish as a model research organism and to provide students with direct experience with current techniques used in embryological research. The content of the lab is designed to generate discussions on embryology, genetics, fertilization, natural selection, and animal adaptation. The protocol produces reliable results in a time-efficient manner using a minimum of reagents. The protocol presented here consists of three sections: observations of live zebrafish larvae at different developmental stages, cartilage staining of zebrafish larvae, and a mutant hunt involving identification of two zebrafish mutants (nacre and chokh). Here, we describe the protocol, show the results obtained for each section, and suggest possible alternatives for different lab settings.
Update on Foregut Molecular Embryology and Role of Regenerative Medicine Therapies

PubMed Central

Perin, Silvia; McCann, Conor J.; Borrelli, Osvaldo; De Coppi, Paolo; Thapar, Nikhil

2017-01-01

Esophageal atresia (OA) represents one of the commonest and most severe developmental disorders of the foregut, the most proximal segment of the gastrointestinal (GI) tract (esophagus and stomach) in embryological terms. Of intrigue is the common origin from this foregut of two very diverse functional entities, the digestive and respiratory systems. OA appears to result from incomplete separation of the ventral and dorsal parts of the foregut during development, resulting in disruption of esophageal anatomy and frequent association with tracheo-oesophageal fistula. Not surprisingly, and likely inherent to OA, are associated abnormalities in components of the enteric neuromusculature and ultimately loss of esophageal functional integrity. An appreciation of such developmental processes and associated defects has not only enhanced our understanding of the etiopathogenesis underlying such devastating defects but also highlighted the potential of novel corrective therapies. There has been considerable progress in the identification and propagation of neural crest stem cells from the GI tract itself or derived from pluripotent cells. Such cells have been successfully transplanted into models of enteric neuropathy confirming their ability to functionally integrate and replenish missing or defective enteric nerves. Combinatorial approaches in tissue engineering hold significant promise for the generation of organ-specific scaffolds such as the esophagus with current initiatives directed toward their cellularization to facilitate optimal function. This chapter outlines the most current understanding of the molecular embryology underlying foregut development and OA, and also explores the promise of regenerative medicine. PMID:28503544
Update on Foregut Molecular Embryology and Role of Regenerative Medicine Therapies.

PubMed

Perin, Silvia; McCann, Conor J; Borrelli, Osvaldo; De Coppi, Paolo; Thapar, Nikhil

2017-01-01

Esophageal atresia (OA) represents one of the commonest and most severe developmental disorders of the foregut, the most proximal segment of the gastrointestinal (GI) tract (esophagus and stomach) in embryological terms. Of intrigue is the common origin from this foregut of two very diverse functional entities, the digestive and respiratory systems. OA appears to result from incomplete separation of the ventral and dorsal parts of the foregut during development, resulting in disruption of esophageal anatomy and frequent association with tracheo-oesophageal fistula. Not surprisingly, and likely inherent to OA, are associated abnormalities in components of the enteric neuromusculature and ultimately loss of esophageal functional integrity. An appreciation of such developmental processes and associated defects has not only enhanced our understanding of the etiopathogenesis underlying such devastating defects but also highlighted the potential of novel corrective therapies. There has been considerable progress in the identification and propagation of neural crest stem cells from the GI tract itself or derived from pluripotent cells. Such cells have been successfully transplanted into models of enteric neuropathy confirming their ability to functionally integrate and replenish missing or defective enteric nerves. Combinatorial approaches in tissue engineering hold significant promise for the generation of organ-specific scaffolds such as the esophagus with current initiatives directed toward their cellularization to facilitate optimal function. This chapter outlines the most current understanding of the molecular embryology underlying foregut development and OA, and also explores the promise of regenerative medicine.
Diabetic Embryopathy: A Developmental Perspective from Fertilization to Adulthood

PubMed Central

Castori, M.

2013-01-01

Maternal diabetes mellitus is one of the strongest human teratogens. Despite recent advances in the fields of clinical embryology, experimental teratology and preventive medicine, diabetes-related perturbations of the maternofetal unit maintain a considerable impact on the Healthcare System. Classic consequences of prenatal exposure to hyperglycemia encompass (early) spontaneous abortions, perinatal death and malformations. The spectrum of related malformations comprises some recurrent blastogenic monotopic patterns, i.e. holoprosencephaly, caudal dysgenesis and oculoauriculovertebral spectrum, as well as pleiotropic syndromes, i.e. femoral hypoplasia-unusual face syndrome. Despite this, most malformed fetuses display multiple blastogenic defects of the VACTERL type, whose (apparently) casual combination preclude recognizing recurrent patterns, but accurately testifies to their developmental stage at onset. With the application of developmental biology in modern medicine, the effects of diabetes on the unborn patient are expanded to include the predisposition to develop insulin resistance in adulthood. The mechanisms underlying the transgenerational correlation between maternal diabetes and proneness to adult disorders in the offspring remain unclear, and the epigenetic plasticity may represent the missing link. In this scenario, a development-driven summary of the multifaced consequences of maternal diabetes on fertility and child health may add a practical resource to the repertoire of available information on early stages of embryogenesis. PMID:23653578
Embryological Development: Evolutionary History, Genetic Bias, and Cellular Environment Control the Flow of Developmental Events, Part II.

ERIC Educational Resources Information Center

Caplan, Arnold I.

1981-01-01

Emphasizes ectodermal-mesodermal interaction but focuses on the genesis of specialized structures like feathers (ectodermal) and muscles, cartilage, and bone. The sum of these interactions and other factors which govern normal development may be important in regulating the regeneration of particular structures in postembryonic individuals.…
Top 10 Lines of Evidence for Human Evolution.

ERIC Educational Resources Information Center

Nickels, Martin

2001-01-01

Provides 10 lines of evidence that support the theory of human evolution. The evidence relates to hierarchical taxonomic classification, comparative anatomy, comparative embryology and development, comparative biochemistry, adaptive compromises, vestigial structures, biogeography, the fossil sequence, ecological coherence of fossil assemblages,…
Use of the Coelomic Grafting Technique for Prolonged ex utero Cultivation of Late Preprimitive Streak-Stage Rabbit Embryos.

PubMed

Püschel, Bernd; Männer, Jörg

2016-01-01

Due to its morphological similarity with the early human embryo, the pregastrulation-stage rabbit may represent an appropriate mammalian model for studying processes involved in early human development. The usability of mammalian embryos for experimental studies depends on the availability of whole embryo culture methods facilitating prolonged ex utero development. While currently used culture methods yield high success rates for embryos from primitive streak stages onward, the success rate of extended cultivation of preprimitive streak-stage mammalian embryos is low for all previously established methods and for all studied species. This limits the usability of preprimitive streak-stage rabbit embryos in experimental embryology. We have tested whether the extraembryonic coelom of 4-day-old chick embryos may be used for prolonged ex utero culture of preprimitive streak-stage rabbit embryos (stage 2, 6.2 days post coitum). We found that, within this environment, stage 2 rabbit blastocysts can be cultured at decreasing success rates (55% after 1 day, 35% after 2 days, 15% after 3 days) up to a maximum of 72 h. Grafted blastocysts can continue development from the onset of gastrulation to early organogenesis and thereby form all structures characterizing age-matched controls (e.g. neural tube, somites, beating heart). Compared to normal controls, successfully cultured embryos developed at a slower rate and finally showed some structural and gross morphological anomalies. The method presented here was originally developed for whole embryo culture of mouse embryos by Gluecksohn-Schoenheimer in 1941. It is a simple and inexpensive method that may represent a useful extension to presently available ex utero culture systems for rabbit embryos. © 2016 S. Karger AG, Basel.
[Fundamental embryology and anatomy of the lateral ventricle].

PubMed

Baroncini, M; Peltier, J; Lejeune, J-P; Le Gars, D

2011-01-01

The lateral ventricles are the C-shaped cavities of the telencephalon. Embryology of theses cavities is recalled as well as the immediate relationship of the frontal horn, the body, the atrium and the temporal and occipital horns. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Effects of ionizing radiation on embryos of the tardigrade Milnesium cf. tardigradum at different stages of development.

PubMed

Beltrán-Pardo, Eliana; Jönsson, K Ingemar; Wojcik, Andrzej; Haghdoost, Siamak; Harms-Ringdahl, Mats; Bermúdez-Cruz, Rosa M; Bernal Villegas, Jaime E

2013-01-01

Tardigrades represent one of the most desiccation and radiation tolerant animals on Earth, and several studies have documented their tolerance in the adult stage. Studies on tolerance during embryological stages are rare, but differential effects of desiccation and freezing on different developmental stages have been reported, as well as dose-dependent effect of gamma irradiation on tardigrade embryos. Here, we report a study evaluating the tolerance of eggs from the eutardigrade Milnesium cf. tardigradum to three doses of gamma radiation (50, 200 and 500 Gy) at the early, middle, and late stage of development. We found that embryos of the middle and late developmental stages were tolerant to all doses, while eggs in the early developmental stage were tolerant only to a dose of 50 Gy, and showed a declining survival with higher dose. We also observed a delay in development of irradiated eggs, suggesting that periods of DNA repair might have taken place after irradiation induced damage. The delay was independent of dose for eggs irradiated in the middle and late stage, possibly indicating a fixed developmental schedule for repair after induced damage. These results show that the tolerance to radiation in tardigrade eggs changes in the course of their development. The mechanisms behind this pattern are unknown, but may relate to changes in mitotic activities over the embryogenesis and/or to activation of response mechanisms to damaged DNA in the course of development.
Effects of Ionizing Radiation on Embryos of the Tardigrade Milnesium cf. tardigradum at Different Stages of Development

PubMed Central

Beltrán-Pardo, Eliana; Jönsson, K. Ingemar; Wojcik, Andrzej; Haghdoost, Siamak; Harms-Ringdahl, Mats; Bermúdez-Cruz, Rosa M.; Bernal Villegas, Jaime E.

2013-01-01

Tardigrades represent one of the most desiccation and radiation tolerant animals on Earth, and several studies have documented their tolerance in the adult stage. Studies on tolerance during embryological stages are rare, but differential effects of desiccation and freezing on different developmental stages have been reported, as well as dose-dependent effect of gamma irradiation on tardigrade embryos. Here, we report a study evaluating the tolerance of eggs from the eutardigrade Milnesium cf. tardigradum to three doses of gamma radiation (50, 200 and 500 Gy) at the early, middle, and late stage of development. We found that embryos of the middle and late developmental stages were tolerant to all doses, while eggs in the early developmental stage were tolerant only to a dose of 50 Gy, and showed a declining survival with higher dose. We also observed a delay in development of irradiated eggs, suggesting that periods of DNA repair might have taken place after irradiation induced damage. The delay was independent of dose for eggs irradiated in the middle and late stage, possibly indicating a fixed developmental schedule for repair after induced damage. These results show that the tolerance to radiation in tardigrade eggs changes in the course of their development. The mechanisms behind this pattern are unknown, but may relate to changes in mitotic activities over the embryogenesis and/or to activation of response mechanisms to damaged DNA in the course of development. PMID:24039737
Observing temporal order in living processes: on the role of time in embryology on the cell level in the 1870s and post-2000.

PubMed

Bock von Wülfingen, Bettina

2015-03-01

The article analyses the role of time in the visual culture of two phases in embryological research: at the end of the nineteenth century, and in the years around 2000. The first case study involves microscopical cytology, the second reproductive genetics. In the 1870s we observe the first of a series of abstractions in research methodology on conception and development, moving from a method propagated as the observation of the "real" living object to the production of stained and fixated objects that are then aligned in temporal order. This process of abstraction ultimately fosters a dissociation between space and time in the research phenomenon, which after 2000 is problematized and explicitly tackled in embryology. Mass data computing made it possible partially to re-include temporal complexity in reproductive genetics in certain, though not all, fields of reproductive genetics. Here research question, instrument and modelling interact in ways that produce very different temporal relationships. Specifically, this article suggests that the different techniques in the late nineteenth century and around 2000 were employed in order to align the time of the researcher with that of the phenomenon and to economize the researcher's work in interaction with the research material's own temporal challenges.
[The contribution of pathologic diagnosis and research of the faculty members engaged in teaching histology and embryology to undergraduate medical studies].

PubMed

Somer, Ljiljana; Dusan, Lalosević; Dolai, Matilda

2007-01-01

The theoretical and practical aspects of teaching are generally defined by the curriculum, but professional experience plays an important role as well. The teaching experience of the faculty members is developed through health services, education and research. THE DEPARTMENT OFHISTOLOGY AND EMBRIOLOGY: This paper reviews the activities of the teaching staff of the Department of Histology and Embryology, pointing to the importance of pathologic diagnostics and research. It underlines the necessity of using some non-standard histologic staining methods on some tissues, organs and pathogens, as well as the results of experimental studies of the endocrine system. The experimental tumor models are used to demonstrate the interdependence of the endocrine and immune systems. Modalities and possibilities of regeneration of the digestive tract and connective tissue mucosa are explained This paper also deals with histologic criteria used for assessment of fetal age and in the diagnosis of developmental malformations. Linear and stereologic methods, used in quantification of normal morphology, the degree of pathologic changes, and regeneration of normal structures in the courses of and after therapy, are given. The authors particularly emphasized the importance of above-mentioned activities in the teaching of Histology and Embryology to undergraduate students.
Organogenesis of heart-vascular system derived from mouse 2 cell stage embryos and from early embryonic stem cells in vitro.

PubMed

Ishiwata, Isamu; Tamagawa, Tomoharu; Tokieda, Yuko; Iguchi, Megumi; Sato, Kahei; Ishikawa, Hiroshi

2003-03-01

Regenerative medical treatment with embryonic stem cells (an ES cell) is a goal for organ transplantation. Structures that are tubular in nature (i.e. blood capillaries) were induced from early embryonic stem (EES) cells in vitro using embryotrophic factor (ETFs). In addition, cardiac muscle cells could be identified as well. However, differentiation of EES cells into a complete cardiovascular system was difficult because 3 germ layer primordial organs are directed embryologically in various ways and it is not possible to guide only cardiovascular organs. Thus, we introduced ETFs after the formation of an embryoid body and were successful in cloning cell clusters that beat, thus deriving only cardiovascular organs. The application of this to the treatment of various cardiovascular diseases is promising.
The Embryology of Gender

ERIC Educational Resources Information Center

Jorge, Juan Carlos

2010-01-01

More than 50 years after the appearance of the term "gender" in the clinical setting, we have yet to uncover the mechanisms and factors that lead to gender identity formation. Based on human embryology principles, the scientific reasoning with regard to the sexual differentiation of the body is erroneously applied to gender identity formation. The…
Drosophila Melanogaster as an Experimental Organism.

ERIC Educational Resources Information Center

Rubin, Gerald M.

1988-01-01

Discusses the role of the fruit fly in genetics research requiring a multidisciplinary approach. Describes embryological and genetic methods used in the experimental analysis of this organism. Outlines the use of Drosophila in the study of the development and function of the nervous system. (RT)
Chordate betagamma-crystallins and the evolutionary developmental biology of the vertebrate lens.

PubMed

Riyahi, Kumars; Shimeld, Sebastian M

2007-07-01

Several animal lineages, including the vertebrates, have evolved sophisticated eyes with lenses that refract light to generate an image. The nearest invertebrate relatives of the vertebrates, such as the ascidians (sea squirts) and amphioxus, have only basic light detecting organs, leading to the widely-held view that the vertebrate lens is an innovation that evolved in early vertebrates. From an embryological perspective the lens is different from the rest of the eye, in that the eye is primarily of neural origin while the lens derives from a non-neural ectodermal placode which invaginates into the developing eye. How such an organ could have evolved has attracted much speculation. Recently, however, molecular developmental studies of sea squirts have started to suggest a possible evolutionary origin for the lens. First, studies of the Pax, Six, Eya and other gene families have indicated that sea squirts have areas of non-neural ectoderm homologous to placodes, suggesting an origin for the embryological characteristics of the lens. Second, the evolution and regulation of the betagamma-crystallins has been studied. These form one of the key crystallin gene families responsible for the transparency of the lens, and regulatory conservation between the betagamma-crystallin gene in the sea squirt Ciona intestinalis and the vertebrate visual system has been experimentally demonstrated. These data, together with knowledge of the morphological, physiological and gene expression similarities between the C. intestinalis ocellus and vertebrate retina, have led us to propose a hypothesis for the evolution of the vertebrate lens and integrated vertebrate eye via the co-option and combination of ancient gene regulatory networks; one controlling morphogenetic aspects of lens development and one controlling the expression of a gene family responsible for the biophysical properties of the lens, with the components of the retina having evolved from an ancestral photoreceptive organ derived from the anterior central nervous system.
Environmental Influences on Genetic Expression: Biological and Behavioral Aspects of Sexual Differentiation.

ERIC Educational Resources Information Center

Kretchmer, Norman, Ed.; Walcher, Dwain N., Ed.

A cross-disciplinary approach to the topic of sexual differentiation comprises this volume. Diverse papers are included under a variety of headings: 1) critical Periods in development; 2) embryology; 3) RNA-DNA; 4) chromosomes-growth and development; 5) physiology; 6) primates; 7) cognition; 8) cultural differences in patterns of sexual behavior;…
The choroid plexus: a comprehensive review of its history, anatomy, function, histology, embryology, and surgical considerations.

PubMed

Mortazavi, Martin M; Griessenauer, Christoph J; Adeeb, Nimer; Deep, Aman; Bavarsad Shahripour, Reza; Shahripour, Reza Bavarsad; Loukas, Marios; Tubbs, Richard Isaiah; Tubbs, R Shane

2014-02-01

The role of the choroid plexus in cerebrospinal fluid production has been identified for more than a century. Over the years, more intensive studies of this structure has lead to a better understanding of the functions, including brain immunity, protection, absorption, and many others. Here, we review the macro- and microanatomical structure of the choroid plexus in addition to its function and embryology. The literature was searched for articles and textbooks for data related to the history, anatomy, physiology, histology, embryology, potential functions, and surgical implications of the choroid plexus. All were gathered and summarized comprehensively. We summarize the literature regarding the choroid plexus and its surgical implications.
The concept of crosstalk-directed embryological target mining and its application to essential hypertension treatment failures.

PubMed

Sag, Alan Alper; Sal, Oguzhan; Kilic, Yagmur; Onal, Emine Meltem; Kanbay, Mehmet

2017-05-01

This review aims to introduce the novel concept of embryological target mining applied to interorgan crosstalk network genesis, and applies embryological target mining to multidrug-resistant essential hypertension (a prototype, complex, undertreated, multiorgan systemic syndrome) to uncover new treatment targets and critique why existing strategies fail. Briefly, interorgan crosstalk pathways represent the next frontier for target mining in molecular medicine. This is because stereotyped stepwise organogenesis presents a unique opportunity to infer interorgan crosstalk pathways that may be crucial to discovering novel treatment targets. Insights gained from this review will be applied to patient management in a clinician-directed fashion. ©2017 Wiley Periodicals, Inc.
Using the Blue Gourami in Ethological and Embryological Studies.

ERIC Educational Resources Information Center

Thompson, Theresa; Pollak, Edward I.

1981-01-01

Lists advantages in the use of the blue gourami in laboratory experiments on reproduction and embryogenesis. Materials and procedures for maintaining and spawning blue gouramis are provided. Also includes details on microscopic examination of developing embryos and histological techniques for microscope slide preparation. (CS)
Computational Embryology and Predictive Toxicology of Hypospadias (SOT)

EPA Science Inventory

Hypospadias, one of the most common birth defects in human male infants, is a condition in which the urethral opening is misplaced along ventral aspect of the penis. We developed an Adverse Outcome Pathway (AOP) framework and computer simulation that describes the pathogenesis of...
A comprehensive review of the foramina of Luschka: history, anatomy, embryology, and surgery.

PubMed

Johal, Jaspreet; Paulk, Phillip Barrett; Oakes, Peter C; Oskouian, Rod J; Loukas, Marios; Tubbs, R Shane

2017-09-01

The purpose of this review is to comprehensively review the foramina of Luschka in regard to their discovery, embryology, anatomy, and surgical relevance. This subject review of the foramina of Luschka was composed after conducting a thorough review of the available literature on this topic using PubMed and other primary sources. The foramina of Luschka are paired apertures located in the lateral recesses of the fourth ventricle, within the posterior cranial fossa. The foramina of Luschka are of importance clinically as their blockage can disrupt the flow of cerebrospinal fluid leading to the development of hydrocephalus. These apertures were first described by the German anatomist Hubert von Luschka in the nineteenth century. These foramina are thought to emerge at around the 26th week of development. The apertures project into the cerebellopontine angle at the lateral border of the pontomedullary sulcus. The foramina of Luschka may be surgically manipulated for the excision of tumors involving the fourth ventricle and surrounding structures and accessed for cochlear nucleus stimulation.
[On a contribution of Boris Balinsky to the comparative and ecological embryology of amphibians].

PubMed

Desnitskiĭ, A G

2014-01-01

The outstanding embryologist Boris Ivanovich Balinsky (1905-1997) worked in the Soviet Union up to 1941 and in South Africa since 1949. His experimental studies fulfilled during the Soviet period of his scientific career mainly on the embryos of the caudate amphibians are widely known. After moving to Africa (Johannesburg), he continued the research of amphibian development, with using those possibilities, which were offered by the diverse fauna of local Anura. Other embryologists started complex studies of tropical frog ontogenies (mainly from South and Central America) 30-40 years later than Balinsky. Unfortunately, his pioneering works on numerous African species are poorly known (with the exceptions of the description of the development of endodermal derivatives in Xenopus laevis and the analysis of limb induction in the toad genus Amietophrynus). In this paper, the works of Balinsky are analyzed (with the emphasis on comparative and ecological aspects) and his priority in using of "nonmodel" tropical and subtropical anurans in embryological studies has been shown.
Characteristics of patients with symbrachydactyly.

PubMed

De Smet, L; Fabry, G

1998-04-01

The clinical and radiologic spectrum of symbrachydactyly has been extended, on the basis of experimental embryology, into four categories: typical symbrachydactyly, atypical cleft hand, monodactyly, and adactyly. The origin of this embryologic failure is probably a vascular disruption. A series of 64 hands and 3 feet are reported, indicating associated anomalies and possible etiologic features.
Material souls and imagination in late Aristotelian embryology.

PubMed

Blank, Andreas

2010-04-01

This article explores some continuities between Late Aristotelian and Cartesian embryology. In particular, it argues that there is an interesting consilience between some accounts of the role of imagination in trait acquisition in Late Aristotelian and Cartesian embryology. Evidence for this thesis is presented using the extensive biological writings of the Padua-based philosopher and physician, Fortunio Liceti (1577-1657). Like the Cartesian physiologists, Liceti believed that animal souls are material beings and that acts of imagination result in material images that can be transmitted by means of medical spirits to the embryo. Moreover, while the Cartesian embryologists accepted such a view in a quite speculative way, one finds penetrating criticism of imagination theories of trait acquisition in the Late Aristotelian tradition. Evidence for this thesis is presented using the no less extensive biological writings of Liceti's contemporary, Emilio Parisano (1567-1643). In conclusion, the Late Aristotelian tradition itself provides the theoretical tools for excising immaterial formative forces from embryology and at the same time evinces a much more acute sense for the problems inherent in imagination theories of trait acquisition than the Cartesian tradition.
The history of female genital tract malformation classifications and proposal of an updated system.

PubMed

Acién, Pedro; Acién, Maribel I

2011-01-01

A correct classification of malformations of the female genital tract is essential to prevent unnecessary and inadequate surgical operations and to compare reproductive results. An ideal classification system should be based on aetiopathogenesis and should suggest the appropriate therapeutic strategy. We conducted a systematic review of relevant articles found in PubMed, Scopus, Scirus and ISI webknowledge, and analysis of historical collections of 'female genital malformations' and 'classifications'. Of 124 full-text articles assessed for eligibility, 64 were included because they contained original general, partial or modified classifications. All the existing classifications were analysed and grouped. The unification of terms and concepts was also analysed. Traditionally, malformations of the female genital tract have been catalogued and classified as Müllerian malformations due to agenesis, lack of fusion, the absence of resorption and lack of posterior development of the Müllerian ducts. The American Fertility Society classification of the late 1980s included seven basic groups of malformations also considering the Müllerian development and the relationship of the malformations to fertility. Other classifications are based on different aspects: functional, defects in vertical fusion, embryological or anatomical (Vagina, Cervix, Uterus, Adnex and Associated Malformation: VCUAM classification). However, an embryological-clinical classification system seems to be the most appropriate. Accepting the need for a new classification system of genitourinary malformations that considers the experience gained from the application of the current classification systems, the aetiopathogenesis and that also suggests the appropriate treatment, we proposed an update of our embryological-clinical classification as a new system with six groups of female genitourinary anomalies.
Embryologic innervation of the rat laryngeal musculature--a model for investigation of recurrent laryngeal nerve reinnervation.

PubMed

Pitman, Michael J; Berzofsky, Craig E; Alli, Opeyemi; Sharma, Sansar

2013-12-01

Optimal management of vocal fold paralysis would entail recurrent laryngeal nerve (RLN) reinnervation resulting in normal vocal fold motion. Unfortunately, RLN reinnervation currently results in a nonfunctional vocal fold due to synkinetic reinnervation. Therapeutic interventions that guide regenerating axons back to the appropriate muscle would prevent synkinesis and restore vocal fold and glottal function. The initial step toward developing these therapies is the elucidation of the embryologic innervation of the larynx. This study aimed to identify the age of occurrence, timing, and pattern of embryologic innervation of the rat larynx, hypothesizing that differences in these parameters exist between distinct laryngeal muscles. Descriptive anatomic study. The larynx of rats aged embryologic day (E) 15, 16, 17, 19, and 21 were harvested and then sectioned. Two rats were used for each age. Sections were colabeled with neuronal class III β-tubulin polyclonal antibody to identify the presence of axons and alexa 488 conjugate α-bungarotoxin to identify the presence of motor endplates. The age at which axons and motor endplates were first present was noted. The position and pattern of the axons and motor endplates was recorded in relation to each other as well as the musculoskeletal anatomy of the larynx. The time at which axons appeared to innervate the medial thyroarytenoid (MTA) muscle, lateral thyroarytenoid (LTA) muscle, and the posterior cricoarytenoid (PCA) muscle was documented. Findings in the rat suggest the RLN reaches the larynx and begins branching by E15. Axons branch dorsally first and reach the PCA muscle before the other muscles. Branching toward the MTA muscle occurs only after axons have reached the LTA muscle. By E19, RLN axons have been guided to and selected their respective muscles with formation of neuromuscular junctions (NMJs) in the PCA, LTA and MTA muscles, though the formation of NMJs in the MTA muscle was comparatively delayed. This study describes the embryologic innervation of the rat larynx and suggests that there are distinct differences in the age of occurrence, timing, and pattern of innervation of the PCA, LTA, and MTA muscles of the rat. These findings lay the foundation for studies investigating the role of guidance cues in RLN axon guidance and the utility of these cues in the treatment of RLN injury via the stimulation of functional, nonsynkinetic reinnervation. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.
Craniopagus twins: surgical anatomy and embryology and their implications.

PubMed Central

O'Connell, J E

1976-01-01

Craniopagus is of two types, partial and total. In the partial form the union is of limited extent, particularly as regards its depth, and separation can be expected to be followed by the survival of both children to lead normal lives. In the total form, of which three varieties can be recognized, the two brains can be regarded as lying within a single cranium and a series of gross intracranial abnormalities develops. These include deformity of the skull base, deformity and displacement of the cerebrum, and a gross circulatory abnormality. It is considered that these and other abnormalities, unlike the primary defect, which is defined, are secondary ones; explanations for them, based on anatomy and embryology, are put forward. The implications of the various anomalies are discussed and the ethical aspects of attempted separation in these major unions considered. Images PMID:1255206

From experimental imaging techniques to virtual embryology.

PubMed

Weninger, Wolfgang J; Tassy, Olivier; Darras, Sébastien; Geyer, Stefan H; Thieffry, Denis

2004-01-01

Modern embryology increasingly relies on descriptive and functional three dimensional (3D) and four dimensional (4D) analysis of physically, optically, or virtually sectioned specimens. To cope with the technical requirements, new methods for high detailed in vivo imaging, as well as the generation of high resolution digital volume data sets for the accurate visualisation of transgene activity and gene product presence, in the context of embryo morphology, were recently developed and are under construction. These methods profoundly change the scientific applicability, appearance and style of modern embryo representations. In this paper, we present an overview of the emerging techniques to create, visualise and administrate embryo representations (databases, digital data sets, 3-4D embryo reconstructions, models, etc.), and discuss the implications of these new methods on the work of modern embryologists, including, research, teaching, the selection of specific model organisms, and potential collaborators.
Management of acute lower extremity deep venous thrombosis in a patient with duplicated inferior vena cava and contraindication to anticoagulation: case and review of the literature.

PubMed

Patel, Shrinil; Cheema, Anmol; Karawadia, Tejas; Carson, Michael

2018-06-04

Duplication of the inferior vena cava (DIVC) is an uncommon embryological anatomic phenomenon.We report a 63-year-old woman with extensive right leg deep vein thrombosis who required an IVC filter due to contraindications for anticoagulation, but was found to have DIVC which required the placement of two IVC filters with good result. This report will review and summarise past reports of DIVC management to provide a guide for future clinicians, and review the embryological development, diagnosis and IVC filter placement options as they are based on the type of anatomic malformation encountered. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Placenta-Like Structure of the Aphid Endoparasitic Wasp Aphidius ervi: A Strategy of Optimal Resources Acquisition

PubMed Central

Sabri, Ahmed; Hance, Thierry; Leroy, Pascal D.; Frère, Isabelle; Haubruge, Eric; Destain, Jacqueline; Compère, Philippe; Thonart, Philippe

2011-01-01

Aphidius ervi (Hymenoptera: Braconidae) is an entomophagous parasitoid known to be an effective parasitoid of several aphid species of economic importance. A reduction of its production cost during mass rearing for inundative release is needed to improve its use in biological control of pests. In these contexts, a careful analysis of its entire development phases within its host is needed. This paper shows that this parasitoid has some characteristics in its embryological development rather complex and different from most other reported insects, which can be phylogenetically very close. First, its yolkless egg allows a high fecundity of the female but force them to hatch from the egg shell rapidly to the host hemocoel. An early cellularisation allowing a rapid differentiation of a serosa membrane seems to confirm this hypothesis. The serosa wraps the developing embryo until the first instar larva stage and invades the host tissues by microvilli projections and form a placenta like structure able to divert host resources and allowing nutrition and respiration of embryo. Such interspecific invasion, at the cellular level, recalls mammal's trophoblasts that anchors maternal uterine wall and underlines the high adaptation of A. ervi to develop in the host body. PMID:21526196
The Role of Platelet-Derived Growth Factor C and Its Splice Variant in Breast Cancer

DTIC Science & Technology

2012-02-01

epithelial-mesenchymal transition leading instead to apoptosis (8). Furthermore, inhibition of PDGFR signaling by the PDGFR inhibitor STI571...PDGFRs are expressed in many different cell types including endothelial, epithelial and neural cells and are necessary for embryological development (as
Minority Undergraduate Research in Prostate Cancer: Bridging Opportunities for Postbaccalaureate Education

DTIC Science & Technology

2011-04-01

Embryology Navpreet Tung DSU Robert Sikes HS-5 Bone Marrow Stromal Cell Conditioned Media may Promote Cell Cycle... Embryology Odinaka C. Anyanwu1, Deborah H. Powell2, Jia L. Song3 and Kirk J. Czymmek2,3 1 Lincoln University
A New Dynamic 3D Virtual Methodology for Teaching the Mechanics of Atrial Septation as Seen in the Human Heart

ERIC Educational Resources Information Center

Schleich, Jean-Marc; Dillenseger, Jean-Louis; Houyel, Lucile; Almange, Claude; Anderson, Robert H.

2009-01-01

Learning embryology remains difficult, since it requires understanding of many complex phenomena. The temporal evolution of developmental events has classically been illustrated using cartoons, which create difficulty in linking spatial and temporal aspects, such correlation being the keystone of descriptive embryology. We synthesized the…
Unusual association of congenital middle ear cholesteatoma and first branchial cleft anomaly: management and embryological concepts.

PubMed

Nicollas, R; Tardivet, L; Bourlière-Najean, B; Sudre-Levillain, I; Triglia, J M

2005-02-01

To report two cases of an undescribed association of first branchial cleft fistula and middle ear congenital cholesteatoma and to discuss management and embryological hypothesis. Retrospective study and review of the literature Both patients were young girls free of past medical or surgical history. Surgical removal of the first cleft anomaly found in the two cases a fistula routing underneath the facial nerve. Both cholesteatomas were located in the hypotympanum, mesotympanum. In one case, an anatomical link between the two malformations was clearly identified with CT scan. The main embryological theories and classification are reviewed. A connection between Aimi's and Michaels' theories (congenital cholesteatoma) and Work classification might explain the reported clinical association.
Development and application of a marine sediment pore-water toxicity test using Ulva fasciata zoospores

USGS Publications Warehouse

Hooten, Russell L.; Carr, R. Scott

1998-01-01

An acute (96 h) pore-water toxicity test protocol using germination and growth of Ulva fasciatazoospores as endpoints was developed to test the toxicity of marine and estuarine sediment pore-water samples. Tests with an organic toxicant (sodium dodecyl sulfate; SDS), three metals (Cd, Cu, and Zn), and ammonia (NH3) were conducted to determine zoospore sensitivity. Zoospore germination and gametophyte growth were as sensitive to SDS as sea urchin (Arbacia punctulata) fertilization and embryological development. Zoospore sensitivity to metals was greater than or comparable to that of adult macroalgae. Zoospores were less sensitive to NH3than were other commonly used toxicity test organisms. Test results using this algal assay with sediment pore-water samples with high NH3 concentrations were compared with results from sea urchin fertilization and embryological development tests for the same samples. Ulva fasciatazoospore germination was not affected by samples with high NH3 concentrations that were toxic in both sea urchin tests. Zoospore tolerance of NH3 and sensitivity to other contaminants indicate that their response may be useful in toxicity identification evaluation studies with pore-water samples that contain high concentrations of unionized NH3.
Tissue architecture, cell traction, deformable scaffolds, and the forces that shape the embryo during morphogenesis.

NASA Astrophysics Data System (ADS)

Davidson, Lance

2005-03-01

Morphogenesis is the process of constucting form and shape. Morphogenesis during early development of the embryo involves orchestrated movements of cells and tissues. These morphogenetic movements establish the body plan and organs of the early embryo. The rates and trajectories of these movements depend on three physical features of the early embryo: 1) the forces generated by cells, 2) the mechanical properties of the tissues, and 3) the architecture of the tissues. These three mechanical features of the embryo are some of the earliest phenotypic features generated by the genome. We are taking an interdisciplinary approach combining biophysical, cell biological, and classical embryological techniques to understand the mechanics of morphogenesis. Using nanoNewton-sensitive force transducers we can apply forces and measure time dependent elastic modulii of tissue fragments 100 micrometers across. Using traction-force microscopy we can measure forces generated by cells on their environment. We use drugs and chimeric proteins to investigate the localization and function of molecular complexes responsible for force generation and the modulus. We use microsurgery to take-apart and construct novel tissues to investigate the role of geometry and architecture in the mechanics of morphogenesis. Together with simulation techniques these quantitative approaches will provide us with a practical nuts-and-bolts understanding of how the genome encodes the shapes and forms of life.
Left Right Patterning, Evolution and Cardiac Development

PubMed Central

Dykes, Iain M.

2018-01-01

Many aspects of heart development are determined by the left right axis and as a result several congenital diseases have their origins in aberrant left-right patterning. Establishment of this axis occurs early in embryogenesis before formation of the linear heart tube yet impacts upon much later morphogenetic events. In this review I discuss the differing mechanisms by which left-right polarity is achieved in the mouse and chick embryos and comment on the evolution of this system. I then discus three major classes of cardiovascular defect associated with aberrant left-right patterning seen in mouse mutants and human disease. I describe phenotypes associated with the determination of atrial identity and venous connections, looping morphogenesis of the heart tube and finally the asymmetric remodelling of the embryonic branchial arch arterial system to form the leftward looped arch of aorta and associated great arteries. Where appropriate, I consider left right patterning defects from an evolutionary perspective, demonstrating how developmental processes have been modified in species over time and illustrating how comparative embryology can aide in our understanding of congenital heart disease. PMID:29755990
Ultrasound Biomicroscopy in Small Animal Research: Applications in Molecular and Preclinical Imaging

PubMed Central

Greco, A.; Mancini, M.; Gargiulo, S.; Gramanzini, M.; Claudio, P. P.; Brunetti, A.; Salvatore, M.

2012-01-01

Ultrasound biomicroscopy (UBM) is a noninvasive multimodality technique that allows high-resolution imaging in mice. It is affordable, widely available, and portable. When it is coupled to Doppler ultrasound with color and power Doppler, it can be used to quantify blood flow and to image microcirculation as well as the response of tumor blood supply to cancer therapy. Target contrast ultrasound combines ultrasound with novel molecular targeted contrast agent to assess biological processes at molecular level. UBM is useful to investigate the growth and differentiation of tumors as well as to detect early molecular expression of cancer-related biomarkers in vivo and to monitor the effects of cancer therapies. It can be also used to visualize the embryological development of mice in uterus or to examine their cardiovascular development. The availability of real-time imaging of mice anatomy allows performing aspiration procedures under ultrasound guidance as well as the microinjection of cells, viruses, or other agents into precise locations. This paper will describe some basic principles of high-resolution imaging equipment, and the most important applications in molecular and preclinical imaging in small animal research. PMID:22163379
Establishment of the Vertebrate Germ Layers.

PubMed

Tseng, Wei-Chia; Munisha, Mumingjiang; Gutierrez, Juan B; Dougan, Scott T

2017-01-01

The process of germ layer formation is a universal feature of animal development. The germ layers separate the cells that produce the internal organs and tissues from those that produce the nervous system and outer tissues. Their discovery in the early nineteenth century transformed embryology from a purely descriptive field into a rigorous scientific discipline, in which hypotheses could be tested by observation and experimentation. By systematically addressing the questions of how the germ layers are formed and how they generate overall body plan, scientists have made fundamental contributions to the fields of evolution, cell signaling, morphogenesis, and stem cell biology. At each step, this work was advanced by the development of innovative methods of observing cell behavior in vivo and in culture. Here, we take an historical approach to describe our current understanding of vertebrate germ layer formation as it relates to the long-standing questions of developmental biology. By comparing how germ layers form in distantly related vertebrate species, we find that highly conserved molecular pathways can be adapted to perform the same function in dramatically different embryonic environments.
Predictive Toxicology and Computer Simulation of Male Reproductive Development (Duke U KURe and PMRC research day)

EPA Science Inventory

The reproductive tract is a complex, integrated organ system with diverse embryology and unique sensitivity to prenatal environmental exposures that disrupt morphoregulatory processes and endocrine signaling. U.S. EPA’s in vitro high-throughput screening (HTS) database (ToxCastDB...
Color Microfiche: Applications to Biomedical Optometric Education.

ERIC Educational Resources Information Center

Wing, Joan Tanabe; Chronister, Connie; Whittaker, Stephen G.; Crozier, Gilda C.

1999-01-01

A color microfiche containing ocular tissue section images was developed and introduced into an ocular history and embryology course to enhance student access to such images. Students found that the materials enhanced their ability to learn. Faculty found that the materials allowed students to prepare in advance for the laboratory, freeing class…
Anatomy Education in Namibia: Balancing Facility Design and Curriculum Development

ERIC Educational Resources Information Center

Wessels, Quenton; Vorster, Willie; Jacobson, Christian

2012-01-01

The anatomy curriculum at Namibia's first, and currently only, medical school is clinically oriented, outcome-based, and includes all of the components of modern anatomical sciences i.e., histology, embryology, neuroanatomy, gross, and clinical anatomy. The design of the facilities and the equipment incorporated into these facilities were directed…
'By the work, one knows the workman': the practice and profession of the embryologist and its translation to quality in the embryology laboratory.

PubMed

Go, Kathryn J

2015-10-01

The embryologist presides over the fulfillment of a patient's treatment in the laboratory for IVF through use of assisted reproduction techniques, and is in a unique position to impart quality to the process. Although the technical skill of the embryologist is critical, the embryologist's contribution to quality is equally conveyed through a knowledge of reproductive biology, keen observation and judgment, astute decision-making, the 'grit' to work under pressure and time constraints, and a sense of mission in the provision and continual development of a safe and effective laboratory. The embryologist also ensures that the laboratory complies with the regulations of federal, state, local and institutional authorities and the recommendations and guidelines of professional associations. In these roles, the embryologist assumes unique responsibilities counterbalanced by the unique rewards of assisting patients in having a family. This article aspires to illuminate this singular profession for those who may be contemplating a career in embryology and act as a resource for those who seek insight into this amalgam of basic science, technical proficiency, and managerial skill and acumen that characterize the practice of clinical embryology and the myriad of ways that practitioners contribute to the quality of assisted reproduction techniques and patient care. Copyright © 2015 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
Embryological outcomes in cycles with human oocytes containing large tubular smooth endoplasmic reticulum clusters after conventional in vitro fertilization.

PubMed

Itoi, Fumiaki; Asano, Yukiko; Shimizu, Masashi; Honnma, Hiroyuki; Murata, Yasutaka

2016-01-01

There have been no studies analyzing the effect of large aggregates of tubular smooth endoplasmic reticulum (aSERT) after conventional in vitro fertilization (cIVF). The aim of this study was to investigate whether aSERT can be identified after cIVF and the association between the embryological outcomes of oocytes in cycles with aSERT. This is a retrospective study examining embryological data from cIVF cycles showing the presence of aSERT in oocytes 5-6 h after cIVF. To evaluate embryo quality, cIVF cycles with at least one aSERT-metaphase II (MII) oocyte observed (cycles with aSERT) were compared to cycles with normal-MII oocytes (control cycles). Among the 4098 MII oocytes observed in 579 cycles, aSERT was detected in 100 MII oocytes in 51 cycles (8.8%). The fertilization rate, the rate of embryo development on day 3 and day 5-6 did not significantly differ between cycles with aSERT and control group. However, aSERT-MII oocytes had lower rates for both blastocysts and good quality blastocysts (p < 0.05). aSERT can be detected in the cytoplasm by removing the cumulus cell 5 h after cIVF. However, aSERT-MII oocytes do not affect other normal-MII oocytes in cycles with aSERT.
When Closure Fails: What the Radiologist Needs to Know About the Embryology, Anatomy, and Prenatal Imaging of Ventral Body Wall Defects.

PubMed

Torres, Ulysses S; Portela-Oliveira, Eduardo; Braga, Fernanda Del Campo Braojos; Werner, Heron; Daltro, Pedro Augusto Nascimento; Souza, Antônio Soares

2015-12-01

Ventral body wall defects (VBWDs) are one of the main categories of human congenital malformations, representing a wide and heterogeneous group of defects sharing a common feature, that is, herniation of one or more viscera through a defect in the anterior body wall. Gastroschisis and omphalocele are the 2 most common congenital VBWDs. Other uncommon anomalies include ectopia cordis and pentalogy of Cantrell, limb-body wall complex, and bladder and cloacal exstrophy. Although VBWDs are associated with multiple abnormalities with distinct embryological origins and that may affect virtually any system organs, at least in relation to anterior body wall defects, they are thought (except for omphalocele) to share a common embryologic mechanism, that is, a failure involving the lateral body wall folds responsible for closing the thoracic, abdominal, and pelvic portions of the ventral body wall during the fourth week of development. Additionally, many of the principles of diagnosis and management are similar for these conditions. Fetal ultrasound (US) in prenatal care allows the diagnosis of most of such defects with subsequent opportunities for parental counseling and optimal perinatal management. Fetal magnetic resonance imaging may be an adjunct to US, providing global and detailed anatomical information, assessing the extent of defects, and also helping to confirm the diagnosis in equivocal cases. Prenatal imaging features of VBWDs may be complex and challenging, often requiring from the radiologist a high level of suspicion and familiarity with the imaging patterns. Because an appropriate management is dependent on an accurate diagnosis and assessment of defects, radiologists should be able to recognize and distinguish between the different VBWDs and their associated anomalies. In this article, we review the relevant embryology of VBWDs to facilitate understanding of the pathologic anatomy and diagnostic imaging approach. Features will be illustrated with prenatal US and magnetic resonance imaging and correlated with postnatal and clinical imaging. Copyright © 2015 Elsevier Inc. All rights reserved.
Learning about Heredity and Embryology. Superific Science Book II. A Good Apple Science Activity Book for Grades 5-8+.

ERIC Educational Resources Information Center

Conway, Lorraine

Designed to provide teachers with low cost laboratory exercises, project ideas, and classroom activities for individuals and groups, this document focuses on the concepts of heredity and embryology. The materials address the topics of: (1) cell division; (2) the identification of the human embryo; (3) chromosomes; (4) DNA; (5) differences in the…
Bronislawa and Mieczyslaw Konopacki - pioneers of the application of histochemistry to embryology in Poland.

PubMed

Bielanska-Osuchowska, Zofia

2008-01-01

In this paper, we review the life and work of Mieczyslaw Konopacki and his wife Bronislawa Konopacka. These Polish scientists introduced histochemical methods to embryological studies at the beginning of the XXth century; they were pioneers in this regard in Poland and among the first in the world to implement such methods in this way.

The Human Fertilisation and Embryology Act of 1990 and Assessment for Parenthood: In Whose Best Interests?

ERIC Educational Resources Information Center

Ryburn, Murray; Fleming, Annette

1993-01-01

Britain's Human Fertilisation and Embryology Act provides for the assessment of adults for parenthood on both medical and social grounds, justified by concern for the welfare of the child. Compares these assessments with those undertaken in the adoption process and questions the utility of such decisions for the welfare of the children involved.…
Vitrification in human and domestic animal embryology: work in progress.

PubMed

Vajta, Gábor

2013-01-01

According to the analysis of papers published in major international journals, rapidly increasing application of vitrification is one of the greatest achievements in domestic animal and especially human embryology during the first decade of our century. This review highlights factors supporting or hampering this progress, summarises results achieved with vitrification and outlines future tasks to fully exploit the benefits of this amazing approach that has changed or will change many aspects of laboratory (and also clinical) embryology. Supporting factors include the simplicity, cost efficiency and convincing success of vitrification compared with other approaches in all species and developmental stages in mammalian embryology, while causes that slow down the progress are mostly of human origin: inadequate tools and solutions, superficial teaching, improper application and unjustified concerns resulting in legal restrictions. Elimination of these hindrances seems to be a slower process and more demanding task than meeting the biological challenge. A key element of future progress will be to pass the pioneer age, establish a consensus regarding biosafety requirements, outline the indispensable features of a standard approach and design fully-automated vitrification machines executing all phases of the procedure, including equilibration, cooling, warming and dilution steps.
A Gift or a Waste? Quintavalle, Surplus Embryos and the Abortion Act 1967.

PubMed

Cherkassky, Lisa

2017-07-01

The destruction of an embryo must be justified in law. This is to prevent frivolous wastage and to show the respect afforded by the Warnock Report (1984). For example, embryonic destruction during pregnancy is underpinned by the Abortion Act 1967, and embryonic destruction during fertility treatment is regulated by the Human Fertilisation and Embryology Act 1990. However, following the appeal decision in R (Quintavalle) v Human Fertilisation and Embryology Authority (and Secretary of State for Health) [2005] 2 A.C. 561, embryos can now be created for a bone marrow tissue match to a sick sibling under the Human Fertility and Embryology Act 1990 according to the subjective desires of the mother. This opens the door to the first example of embryonic destruction on unique social-eugenic grounds with no clear lawful justification. It is argued that these embryos should be afforded a unique destruction provision under an amended version of section 1(1)(a) of the Abortion Act 1967 in light of their 'social-eugenic' nature. This would protect the Human Fertilisation and Embryology Authority from accusations of undercover eugenic practices and reinstate the respect shown towards embryos in law.
Spondylocostal dysostosis associated with right-sided polythelia, right-sided rib deformity and meningocoele: Case report with review of literature.

PubMed

Rai, Narendra; Thakur, Neha; Khan, Naheed Zin; Dwivedi, Akhilesh Dutt

2015-01-01

Spondylocostal dysostosis (SCD) is a rare anomaly of axial skeleton due to flawed embryological development. A newborn baby boy with right-sided polythelia, meningocoele, fan-like configuration of third and fourth rib, fused fifth and sixth rib and third thoracic hemivertebra was delivered to a second gravid mother by elective caesarean section. Baby was active, cried immediately after birth, had normal muscle tone and reflexes. He passed urine and meconium within 24 h of birth. Based on clinical examination and radiological picture, a diagnosis of SCD with meningocele with right-sided polythelia was made. Our case is the first SCD with polythelia and meningocele in newborn. SCD with right-sided polythelia and rib deformity with neural tube defect (NTD) may be due to a genetic defect with the culprit genes missing. Further genetic and embryological studies might find a link between right-sided rib defects, polythelia and NTD.
[Disciplinar thematic integration in medicine: a proposal from histology and embryology].

PubMed

Bassan, N D; D'Ottavio, A E

2013-01-01

This paper intends to clarify a concept with multiple meanings and a complex reality. It starts providing varied histological and embryological examples apt to contribute the stimulation of teacher and student imaginations in favor of a crucial skill, as thematic integration is, into the present and changing curricula in Medicine in particular and Health Sciences in general. In this sense, it offers linear and branched sequences as well as consolidation graphics which focusing in both disciplines may also include other basic ones, key for clinic diagnosis, among the competences to be developed. After registering some preliminary results revealing the need of its continuous and progressive training along the complete medical career, its own integrative value and the integrative one for their teachers due to its natural link with other basic ones is outlined, its relevance for undergraduate is reaffirmed and possible future variations for them are previewed, considering the present exponential growth of science and technology.
A glance at Spanish embryology and teratology during the XX century through the academic life of Francisco Orts-Llorca (1905-1993).

PubMed

Aréchaga, Juan; Jiménez-Collado, Juan; Ruano-Gil, Domingo

2009-01-01

Francisco Ort-Llorca (1905-1993) was one of the most outstanding Spanish embryologists of the XX century. He was disciple of Henri Rouvire in Paris (France), Alfred Fischel in Vienna (Austria), Walther Vogt in Munich (Germany) and Pedro Ara in Madrid (Spain). From 1935, he was professor of Human Anatomy at the Faculty of Medicine of Cadiz, belonged then to the University of Seville (accidentally, in the University of Valencia, during the Spanish Civil War from 1936-1939) and, later on, at the Faculty of Medicine of Madrid (Complutense University) from 1954 to 1975. He was internationally recognized in anatomical sciences and stood out for his contributions to descriptive and experimental Embryology and Teratology, particularly in those aspects connected to the normal and pathological development of the heart and visual organs.
The Epidemiological, Morphological, and Clinical Aspects of the Cervical Ribs in Humans

PubMed Central

Spadliński, Łukasz; Cecot, Tomasz; Majos, Agata; Stefańczyk, Ludomir; Pietruszewska, Wioletta; Wysiadecki, Grzegorz; Topol, Mirosław

2016-01-01

A familiarity with the anatomy of some types of bone anomalies is necessary for clinicians involved in many medical areas. The aim of this paper is to review the newest literature concerning the morphology, embryology, clinical image, and therapeutic methods of the cervical ribs in the humans. The incidence of cervical ribs has been found to vary from 0.58% in Malaysian population to 6.2% in Turkish population. Cervical ribs have clinical implications that are generally divided into neurological or vascular. This study is of particular importance for clinicians, as early identification of cervical ribs may prevent life-threatening complications. PMID:27975060
Was Aristotle the 'father' of the epigenesis doctrine?

PubMed

Goy, Ina

2018-04-04

Was Aristotle the 'father' and founder of the epigenesis doctrine? Historically, I will argue, this question must be answered with 'no'. Aristotle did not initiate and had no access to a debate that described itself in terms of 'epigenesis' and 'preformation', and thus cannot be considered the 'father' or founder of the epigenesis-preformation controversy in a literal sense. But many ancient accounts of reproduction and embryological development contain analogies to what early modern scientist called 'epigenesis' and 'preformation', and, in this analogous sense, Aristotle can be considered a precursor of the epigenesis-preformation controversy. But is Aristotle's position actually epigenetic (in this analogous sense), as most of the traditional interpreters hold, or preformationist, as some of the recent scholars believe? I will argue against the one-sidedness of both readings that Aristotle's account of reproduction and heredity contains mainly epigenetic, but also a few preformationist characteristics. Whereas, for instance, Aristotle's idea of a successive development of the embryo's parts is doubtlessly epigenetic, Aristotle's idea that the development of the embryo is an actualization and enlargement of potential parts, which are simultaneously present in the semen, can be considered a preformationist feature.
Perspectives on the use of the baboon in embryology and teratology research.

PubMed

Hendrickx, A G; Peterson, P E

1997-01-01

This paper summarizes the developmental stages of the baboon during the period of organ formation and provides comparative information for other primates, including the human. Special attention is directed to the early development of the nervous system, eye, ear and nose/palate. The similarity in development of these structures with humans indicates that the baboon is a suitable model for studies of normal and abnormal neurological development. Spontaneous prenatal loss rates in the baboon (2.4-11.2%) are slightly lower than those reported in rhesus and cynomologus monkeys. The baboon, in addition to the cynomologus monkey and macaque, has been used as a model in teratology research to assess the potential risk of thalidomide, sex steroids, Bendectin and rubella virus, as well as to study the pathogenesis of malformations associated with the corticosteroid triamcinolone acetonide. The rate of spontaneous malformations (<1%) in baboons, similar to that reported for other commonly used primates, supports their continued use as a teratological model. In this regard, a sample protocol is provided for the safety evaluation of biotechnology products using nonhuman primates, which are the most appropriate model for those compounds which are bioactive in species closely related to humans.
Time-lapse evaluation of human embryo development in single versus sequential culture media--a sibling oocyte study.

PubMed

Ciray, Haydar Nadir; Aksoy, Turan; Goktas, Cihan; Ozturk, Bilgen; Bahceci, Mustafa

2012-09-01

To compare the dynamics of early development between embryos cultured in single and sequential media. Randomized, comparative study. Private IVF centre. A total of 446 metaphase II oocytes from 51 couples who underwent oocyte retrieval procedure for intracytoplasmic sperm injection. Forty-nine resulted in embryo transfer. Oocytes were split between single and sequential media produced by the same manufacturer and cultured in a time-lapse incubator. Morphokinetic parameters until the embryos reached the 5-cell stage (t5), utilization, clinical pregnancy and implantation rates. Embryos cultured in single media were advanced from the first mitosis cycle and reached 2- to 5-cell stages earlier. There was not any difference between the durations for cell cycle two (cc2 = t3-t2) and s2 (t4-t3). The utilization, clinical pregnancy and implantation rates did not differ between groups. The proportion of cryopreserved day 6 embryos to two pronuclei oocytes was significantly higher in sequential than in single media. Morphokinetics of embryo development vary between single and sequential culture media at least until the 5-cell stage. The overall clinical and embryological parameters remain similar regardless of the culture system.
Embryology of Cardiopteris (Cardiopteridaceae, Aquifoliales), with emphasis on unusual ovule and seed development.

PubMed

Tobe, Hiroshi

2016-09-01

Cardiopteris (Cardiopteridaceae), a twining herb of two or three species distributed from Southeast Asia to Northern Australia, requires an embryological study for better understanding of its reproductive features. The present study of C. quinqueloba showed that the ovule and seed development involves a number of unusual structures, most of which are unknown elsewhere in angiosperms. The ovule pendant from the apical placenta is straight (not orthotropous), ategmic, and tenuinucellate, developing a monosporic seven-celled/eight-nucleate female gametophyte with an egg apparatus on the funicular side. Fertilization occurs by a pollen tube entering from the funicular side, resulting in a zygote on the funicular side. The endosperm is formed by the cell on the funicular side in the two endosperm cell stage. While retaining a (pro)embryo/endosperm as it is, the raphe (differentiating late in pre-fertilization stages) elongates toward the antiraphal side during post-fertilization stages, resulting in an anatropous seed. The two-cell-layered nucellar epidermis (belatedly forming by periclinal divisions), along with the raphe, envelops the embryo/endosperm entirely as the seed coat. The possibility was discussed that the arrested integument development triggers a series of the subsequent unusual structures of ovule and seed development. The fertilization mode in Cardiopteris underpins the hypothesis that the Polygonum‒type female gametophyte comprises two four-celled archegonia.
ZIC2 in Holoprosencephaly.

PubMed

Barratt, Kristen S; Arkell, Ruth M

2018-01-01

The ZIC2 transcription factor is one of the most commonly mutated genes in Holoprosencephaly (HPE) probands. HPE is a severe congenital defect of forebrain development which occurs when the cerebral hemispheres fail to separate during the early stages of organogenesis and is typically associated with mispatterning of the embryonic midline. Recent study of genotype-phenotype correlations in HPE cases has defined distinctive features of ZIC2-associated HPE presentation and genetics, revealing that ZIC2 mutation does not produce the craniofacial abnormalities generally thought to characterise HPE but leads to a range of non-forebrain phenotypes. Furthermore, the studies confirm the extent of ZIC2 allelic heterogeneity and that pathogenic variants of ZIC2 are associated with both classic and middle interhemispheric variant (MIHV) HPE which arise from defective ventral and dorsal forebrain patterning, respectively. An allelic series of mouse mutants has helped to delineate the cellular and molecular mechanisms by which one gene leads to defects in these related but distinct embryological processes.
Recommended practices for the management of embryology, andrology, and endocrinology laboratories: a committee opinion.

PubMed

2014-10-01

This document provides a general overview for physicians of the qualities and conditions necessary for good management practices within the endocrinology, andrology, and embryology laboratories in the United States. It is intended as an addendum to previously published guidelines that further detail these responsibilities. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Organ culture as a technique for casual embryology and its application in radiobiology (in German)

DOE Office of Scientific and Technical Information (OSTI.GOV)

BORGHESE, ELIO

1961-11-01

The classical methods of experimental embryology in amplubia are compared with the more recently introduced technique of culture in vitro of embryonic organs of warmblooded animals. Some isolation and recombination experiments carried out by means of organ culture are described. It is shown, by examples taken from research in progress, how this technique is applicable radiobiological experiments.
An Eight-Year Study of Online Lecture Use in a Medical Gross Anatomy and Embryology Course

ERIC Educational Resources Information Center

Nieder, Gary L.; Borges, Nicole J.

2012-01-01

Online lectures have been used in lieu of live lectures in our gross anatomy and embryology course for the past eight years. We examined patterns of online lecture use by our students and related that use to academic entry measures, gender and examination performance. Detailed access records identified by student were available from server logs.…
Current issues in medically assisted reproduction and genetics in Europe: research, clinical practice, ethics, legal issues and policy.

PubMed

Harper, Joyce; Geraedts, Joep; Borry, Pascal; Cornel, Martina C; Dondorp, Wybo J; Gianaroli, Luca; Harton, Gary; Milachich, Tanya; Kääriäinen, Helena; Liebaers, Inge; Morris, Michael; Sequeiros, Jorge; Sermon, Karen; Shenfield, Françoise; Skirton, Heather; Soini, Sirpa; Spits, Claudia; Veiga, Anna; Vermeesch, Joris Robert; Viville, Stéphane; de Wert, Guido; Macek, Milan

2014-08-01

How has the interface between genetics and assisted reproduction technology (ART) evolved since 2005? The interface between ART and genetics has become more entwined as we increase our understanding about the genetics of infertility and we are able to perform more comprehensive genetic testing. In March 2005, a group of experts from the European Society of Human Genetics and European Society of Human Reproduction and Embryology met to discuss the interface between genetics and ART and published an extended background paper, recommendations and two Editorials. An interdisciplinary workshop was held, involving representatives of both professional societies and experts from the European Union Eurogentest2 Coordination Action Project. In March 2012, a group of experts from the European Society of Human Genetics, the European Society of Human Reproduction and Embryology and the EuroGentest2 Coordination Action Project met to discuss developments at the interface between clinical genetics and ART. As more genetic causes of reproductive failure are now recognized and an increasing number of patients undergo testing of their genome prior to conception, either in regular health care or in the context of direct-to-consumer testing, the need for genetic counselling and PGD may increase. Preimplantation genetic screening (PGS) thus far does not have evidence from RCTs to substantiate that the technique is both effective and efficient. Whole genome sequencing may create greater challenges both in the technological and interpretational domains, and requires further reflection about the ethics of genetic testing in ART and PGD/PGS. Diagnostic laboratories should be reporting their results according to internationally accepted accreditation standards (ISO 15189). Further studies are needed in order to address issues related to the impact of ART on epigenetic reprogramming of the early embryo. The legal landscape regarding assisted reproduction is evolving, but still remains very heterogeneous and often contradictory. The lack of legal harmonization and uneven access to infertility treatment and PGD/PGS fosters considerable cross-border reproductive care in Europe, and beyond. This continually evolving field requires communication between the clinical genetics and IVF teams and patients to ensure that they are fully informed and can make well-considered choices. Funding was received from ESHRE, ESHG and EuroGentest2 European Union Coordination Action project (FP7 - HEALTH-F4-2010-26146) to support attendance at this meeting. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Congenital neck masses.

PubMed

Rosa, Peter A; Hirsch, David L; Dierks, Eric J

2008-08-01

Congenital neck lesions reflect abnormal embryogenesis in head and neck development. A thorough knowledge of embryology and anatomy is critical in the diagnosis and treatment of these lesions. The appropriate diagnosis of these lesions is necessary to provide appropriate treatment and long-term follow up, because some of these lesions may undergo malignant transformation or be harbingers of malignant disease.
An Update on the Status of Anatomical Sciences Education in United States Medical Schools

ERIC Educational Resources Information Center

Drake, Richard L.; McBride, Jennifer M.; Pawlina, Wojciech

2014-01-01

Curricular changes continue at United States medical schools and directors of gross anatomy, microscopic anatomy, neuroscience/neuroanatomy, and embryology courses continue to adjust and modify their offerings. Developing and supplying data related to current trends in anatomical sciences education is important if informed decisions are going to…
An unusual presentation of presentation of a branchial cleft cyst.

PubMed

Vemula, Rahul; Greco, Gregory

2012-05-01

Branchial cleft cysts are congenital anomalies that arise from the aberrant embryological development of the branchial apparatus. The location of a branchial cleft cyst is determined by which branchial cleft failed to obliterate during embryological development, with the second branchial cleft cyst being the most commonly recognized lesion. Although the most common location for branchial cleft cysts is between the external auditory canal and the level of the clavicle, the literature does describe unusual locations. We present a case a 15-year-old boy who had an enlarging lesion on his back that had been present since birth. A presumptive radiologic diagnosis of lymphangioma circumscriptum was made. Upon excision of the lesion and pathologic examination, it was determined to be a branchial cleft cyst. The patient had an uneventful postoperative course, and no recurrence was noted after a 2-year follow-up. Our clinical report demonstrates a lesion on the posterior thorax that proved to be a branchial cleft cyst and should always be part of the differential diagnosis for soft tissue masses of the thorax.
The neuropsychology of development hemispheric laterality, limbic language, and the origin of thought.

PubMed

Joseph, R

1982-01-01

Discussed evidence and assumptions that concern hemispheric laterality and asymmetrical functional representation. It is hypothesized that the asymmetrical linguistic-motor vs. sensory-spatial-affective representation of function may be a result of differential rates of cortical, subcortical and spinal motor-sensory maturation. Evidence with regard to embryological and early postnatal neurological development is reviewed. It is argued that motor areas mature before sensory and that the left hemisphere develops prior to the right, such that the left hemisphere gains a competitive advantage in the acquisition of motor representation, whereas the later maturing right has an advantage in the establishment of sensory-affective synaptic representation, including that of limbic mediation. The influences of these differing maturational events on cognitive and psychic functioning are examined, particularly with regard to limbic influences on the development of language, thought, and mental imagery, and the effects of early emotional experience on later behavior. Thinking is viewed in part as a left hemisphere internalization of egocentric language, the internalization of which corresponds to the increasing maturation of intra-cortical and subcortical structures and fiber pathways, and the myelination of the callosal connections that subserve information transfer between the hemispheres. It is argued that thought is a means of organizing, interpreting, and explaining impulses that arise in the non-linguistic portions of the nervous system so that the language dependent regions may achieve understanding. In addition, the neurodynamics and mechanisms involved in the mislabeling, misinterpretation, and inhibition of impulses, desires, and emotional expression are discussed in relation to disturbances in psychic functioning.

The Veiled Chameleon (Chamaeleo calyptratus Duméril and Duméril 1851): A Model for Studying Reptile Body Plan Development and Evolution.

PubMed

Diaz, Raul E; Anderson, Christopher V; Baumann, Diana P; Kupronis, Richard; Jewell, David; Piraquive, Christina; Kupronis, Jill; Winter, Kristy; Bertocchini, Federica; Trainor, Paul A

2015-08-26

Vertebrate model organisms have facilitated the discovery and exploration of morphogenetic events and developmental pathways that underpin normal and pathological embryological events. In contrast to amniotes such as Mus musculus (Mammalia) and Gallus gallus (Aves), our understanding of early patterning and developmental events in reptiles (particularly nonavians) remains weak. Squamate reptiles (lizards, snakes, and amphisbaenians) comprise approximately one-third of all living amniotes. But studies of early squamate development have been limited because, in most members of this lineage, embryo development at the time of oviposition is very advanced (limb bud stages and older). In many cases, squamates give birth to fully developed offspring. However, in the veiled chameleon (Chamaeleo calyptratus), embryos have progressed only to a primitive pregastrula stage at the time of oviposition. Furthermore, the body plan of the veiled chameleon is highly specialized for climbing in an arboreal environment. It possesses an entire suite of skeletal and soft anatomical modifications, including cranioskeletal ornamentation, lingual anatomy and biomechanics for projection, autopodial clefting for grasping, adaptations for rapid integumental color changes, a prehensile tail with a lack of caudal autotomy, the loss of the tympanum in the middle ear, and the acquisition of turreted eyes. Thus, C. calyptratus is an important model organism for studying the role of ecological niche specialization, as well as genetic and morphological evolution within an adaptive framework. More importantly, this species is easily bred in captivity, with only a small colony (<10 individuals) needed to obtain hundreds of embryos every year. © 2015 Cold Spring Harbor Laboratory Press.
Historical Perspective of Split Cord Malformations: A Tale of Two Cords.

PubMed

Saker, Erfanul; Loukas, Marios; Fisahn, Christian; Oskouian, Rod J; Tubbs, R Shane

2017-01-01

Our appreciation and understanding of what is now known as the split cord malformation (SCM) have a long history. The oldest known example of SCM is from roughly AD 100. Other isolated examples can be found in the large body of work of the pathologists of the 1800s, where the SCMs were found incidentally during autopsies. SCM has a rich history and has intrigued physicians for over 200 years. Many well-known figures from the past such as Chiari and von Recklinghausen, both pathologists, made early postmortem descriptions of SCM. With the advent of MRI, these pathological embryological derailments can now often be detected and appreciated early and during life. Our understanding and ability to treat these congenital malformations as well as the terminology used to describe them have changed over the last several decades. © 2016 S. Karger AG, Basel.
THE HISTORY AND ENDURING CONTRIBUTIONS OF PLANARIANS TO THE STUDY OF ANIMAL REGENERATION

PubMed Central

Elliott, Sarah A.; Sánchez Alvarado, Alejandro

2012-01-01

Having an almost unlimited capacity to regenerate tissues lost to age and injury, planarians have long fascinated naturalists. In the Western hemisphere alone, their documented history spans more than 200 years. Planarians were described in the early 19th century as being “immortal under the edge of the knife,” and initial investigation of these remarkable animals was significantly influenced by studies of regeneration in other organisms and from the flourishing field of experimental embryology in the late 19th and early 20th centuries. This review strives to place the study of planarian regeneration into a broader historical context by focusing on the significance and evolution of knowledge in this field. It also synthesizes our current molecular understanding of the mechanisms of planarian regeneration uncovered since this animal’s relatively recent entrance into the molecular-genetic age. PMID:23799578
Characterizing early embryonic development of Brown Tsaiya Ducks (Anas platyrhynchos) in comparison with Taiwan Country Chicken (Gallus gallus domestics)

PubMed Central

Lumsangkul, Chompunut; Fan, Yang-Kwang; Chang, Shen-Chang; Ju, Jyh-Cherng

2018-01-01

Avian embryos are among the most convenient and the primary representatives for the study of classical embryology. It is well-known that the hatching time of duck embryos is approximately one week longer than that of chicken embryos. However, the key features associated with the slower embryonic development in ducks have not been adequately described. This study aimed to characterize the pattern and the speed of early embryogenesis in Brown Tsaiya Ducks (BTD) compared with those in Taiwan Country Chicken (TCC) by using growth parameters including embryonic crown-tail length (ECTL), primitive streak formation, somitogenesis, and other development-related parameters, during the first 72 h of incubation. Three hundred and sixty eggs from BTD and TCC, respectively, were incubated at 37.2°C, and were then dissected hourly to evaluate their developmental stages. We found that morphological changes of TCC embryos shared a major similarity with that of the Hamburger and Hamilton staging system during early chick embryogenesis. The initial primitive streak in TCC emerged between 6 and 7 h post-incubation, but its emergence was delayed until 10 to 13 h post-incubation in BTD. Similarly, the limb primordia (wing and limb buds) were observed at 51 h post-incubation in TCC embryos compared to 64 h post-incubation in BTD embryos. The allantois first appeared around 65 to 68 h in TCC embryos, but it was not observed in BTD embryos. At the 72 h post-incubation, 40 somites were clearly formed in TCC embryos while only 32 somites in BTD embryos. Overall, the BTD embryos developed approximately 16 h slower than the chicken embryo during the first 72 h of development. To our best knowledge, this is the first study to describe two distinct developmental time courses between TCC and BTD, which would facilitate future embryogenesis-related studies of the two important avian species in Taiwan. PMID:29742160
[Embryology of the heart walls].

PubMed

Tardy, M-M; Galvaing, G; Sakka, L; Garcier, J-M; Chazal, J; Filaire, M

2013-03-01

Although anatomically simple structures, the atrial septum and the ventricular septum have complex embryological origins. Recent findings in molecular biology allowed better comprehension of their formation. As soon as the heart tube is formed, cells migrate from several cardiogenic fields to take part in the septation. Elongation, ballooning, and later inflexion of the heart tube create chamber separating grooves, facing the future septa. The systemic venous tributaries conflate at the venous pole of the heart; it will partially involute while contributing to the atrial septum. The primary atrial septum grows from the atrial roof towards the atrioventricular canal. It fuses there with the atrioventricular cushions, while its upper margin breaks down to form the ostium secundum. Then a deep fold develops from the atrial roof and partly covers the ostium secundum, leaving a flap-like interatrial communication through the oval foramen. It will close at birth. The interventricular septum has three embryological origins. The ventricular septum primum, created during the ballooning process, origins from the primary heart tube. It will form the trabecular septum and the inlet septum. The interventricular ring, surrounding the interventricular foramen, will participate in the inlet septum and also form the atrioventricular conduction axis. The outflow cushions will separate the outflow tract in the aorta and pulmonary artery, and grow to create the outlet septum. After merging with the atrioventricular cushions, they will also be part of the membranous septum. Copyright © 2012 Elsevier Masson SAS. All rights reserved.
THE EFFECTS OF IONIZING RADIATIONS ON THE DEVELOPING ANIMAL WITH SPECIAL REFERENCE TO THE NERVOUS SYSTEM. Progress Report and Application of Renewal of Atomic Energy Commission Contract AT(30-1)-1454

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hicks, S.P.

1960-06-01

Findings are summarized from studies on the effects of radiation on the development of the nervous system in mammals. Radiation has been proven to be a useful tool for experimental mammalian embryology in studies of normal brain development as well as in studies of abnormalities of brain development. Manuscripts are included of papers accepted for publication. (C.H.)
Early embryonic development of the head region of Gryllus assimilis Fabricius, 1775 (Orthoptera, Insecta).

PubMed

Liu, Yu; Maas, Andreas; Waloszek, Dieter

2010-09-01

We report our investigations on the embryonic development of Gryllus assimilis, with particular attention to the head. Significant findings revealed with scanning electron microscopy (SEM) images include: (1) the pre-antennal lobes represent the anterior-most segment that does not bear any appendages; (2) each of the lobes consists of central and marginal regions; (3) the central region thereof develops into the protocerebrum and the optic lobes, whereas the marginal region thereof becomes the anterior portion of the head capsule; (4) the initial position of the antennal segment is posterior to the mouth region; (5) appendage anlagen are transitorily present in the intercalary segment, and they later vanish together with the segment itself; (6) a bulged sternum appears to develop from the ventral surface of the mandibular, maxillary and labial segments. Embryonic features are then compared across the Insecta and further extended to the embryos of a spider (Araneae, Chelicerata). Striking similarities shared by the anterior-most region of the insect and spider embryos lead the authors to conclude that such comparison should be further undertaken to cover the entire Euarthropoda. This will help us to understand the embryology and evolution of the arthropod head. Copyright © 2010 Elsevier Ltd. All rights reserved.
The Plymouth Laboratory and the institutionalization of experimental zoology in Britain in the 1920s.

PubMed

Erlingsson, Steindór J

2009-01-01

The Plymouth Laboratory of the Marine Biological Association of the United Kingdom (1884) was founded in 1888. In addition to conducting morphological and other biological research, the founders of the laboratory aimed at promoting research in experimental zoology which will be used in this paper as a synonym for e.g. experimental embryology, comparative physiology or general physiology. This dream was not fully realized until 1920. The Great War and its immediate aftermath had a positive impact on the development of the Plymouth Laboratory. The war greatly upset the operation of the Zoological Station in Naples and the ensuing crisis in its operations was closely related to the establishment of the physiological department in Plymouth in 1920. Two other key factors in the Plymouth story were the establishment of the Development Fund in 1909, which began contributing funds to the Plymouth Laboratory in 1912, and the patronage of the Cambridge zoologist George P. Bidder (1863-1954). This paper will focus on the combined influence of the Development Fund and Bidder on the development of the Plymouth Laboratory from around 1902 through the early 1920s, and the important role the laboratory played in promoting experimental zoology in Britain in the 1920s.
ANIMATED SERIAL SECTIONS, A TEACHING AID FOR ORAL HISTOLOGY AND EMBRYOLOGY.

ERIC Educational Resources Information Center

HAYDEN, JESS; AND OTHERS

THE RELATIVE EFFECTIVENESS OF TWO TYPES OF VISUAL MEDIA FOR THE DEVELOPMENT OF A THREE-DIMENSIONAL CONCEPT OF A GIVEN ANATOMICAL REGION WAS INVESTIGATED. EXPERIMENTAL AND CONTROL GROUPS WERE RANDOMLY SELECTED FROM 119 FIRST-YEAR MEDICAL AND DENTAL STUDENTS IN AN HISTOLOGY CLASS. BOTH GROUPS ATTENDED THE SAME ONE-HOUR LECTURE. FOLLOWING THE LECTURE…
Master in Oral Biology Program: A Path to Addressing the Need for Future Dental Educators

ERIC Educational Resources Information Center

Jergenson, Margaret A.; Barritt, Laura C.; O'Kane, Barbara J.; Norton, Neil S.

2017-01-01

In dental education, the anatomical sciences, which include gross anatomy, histology, embryology, and neuroanatomy, encompass an important component of the basic science curriculum. At Creighton University School of Dentistry, strength in anatomic science education has been coupled with a solid applicant pool to develop a novel Master of Science…
Update on embryology of the upper limb.

PubMed

Al-Qattan, Mohammad M; Kozin, Scott H

2013-09-01

Current concepts in the steps of upper limb development and the way the limb is patterned along its 3 spatial axes are reviewed. Finally, the embryogenesis of various congenital hand anomalies is delineated with an emphasis on the pathogenetic basis for each anomaly. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.
Bikini scientific resurvey. Volume II. Report of the technical director. Technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1947-12-01

Contents: Island and Reef Geology; Submarine Geology; Drilling Operations; Radiobiology Studies; Reef and Lagoon Fishes; Pelagic Fishes; Taxonomy and Teratology of Fishes; Invertebrate Embryology; Vertebrate Embryology; Reef and Lagoon Algae; Chemical Effects of Organisms Upon Sea Water; The Insect Population; Marine Invertebrates; Land Animals; Plankton Studies; Counter-Room Activities; Radiochemical Analyses; Soils Chemistry; Low-Level Radiation Studies; Army Engineering Studies; Aerological Data; Bacteriological Investigations; Radiological Safety; Radiological Health; Technical Director's Summary.
Importance of supply integrity for in vitro fertilization and embryo culture.

PubMed

Morbeck, Dean E

2012-06-01

The quality of in vitro culture conditions is a key component of a successful clinical embryology laboratory. Many, but not all, supplies used in the embryology laboratory are screened by the supplier with a bioassay. Embryology laboratories use a variety of approaches to verify the quality of mineral oil, protein, and disposables before clinical use; however, a best practice has not been determined. Some laboratories test every supply, even those already screened by the supplier, whereas other laboratories perform as little testing as possible. Despite screening by the supplier, recent reports of embryo toxicity, specifically with mineral oil, highlight that the integrity of the supply system has gaps. This review describes current bioassay quality control testing and discusses how it applies to screening of products with documented lot-to-lot variation. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Cancer Is to Embryology as Mutation Is to Genetics: Hypothesis of the Cancer as Embryological Phenomenon

PubMed Central

Abdelhay, Eliana

2017-01-01

Despite numerous advances in cell biology, genetics, and developmental biology, cancer origin has been attributed to genetic mechanisms primarily involving mutations. Embryologists have expressed timidly cancer embryological origin with little success in leveraging the discussion that cancer could involve a set of conventional cellular processes used to build the embryo during morphogenesis. Thus, this “cancer process” allows the harmonious and coherent construction of the embryo structural base, and its implementation as the embryonic process involves joint regulation of differentiation, proliferation, cell invasion, and migration, enabling the human being recreation of every generation. On the other hand, “cancer disease” is the representation of an abnormal state of the cell that might happen in the stem cells of an adult person, in which the mechanism for joint gene regulating of differentiation, proliferation, cell invasion, and migration could be reactivated in an entirely inappropriate context. PMID:28553657
Delayed rotation of the cerebellar vermis: a pitfall in early second-trimester fetal magnetic resonance imaging.

PubMed

Pinto, J; Paladini, D; Severino, M; Morana, G; Pais, R; Martinetti, C; Rossi, A

2016-07-01

We describe two cases in which delayed rotation of the cerebellar vermis simulated a Dandy-Walker malformation (DWM) on early second-trimester magnetic resonance imaging (MRI). Two pregnant women with suspected fetal posterior fossa anomaly on ultrasound examination underwent fetal MRI at 21 (Case 1) and 19 (Case 2) weeks' gestation. In both cases, upward rotation of the cerebellar vermis was noted; on midsagittal imaging, the brainstem-vermis angle was 28° and 43°, respectively, while cerebellar morphometry showed a reduced vermian anteroposterior diameter compared to reference data. The posterior fossa appeared to be mildly enlarged, while all other findings were normal. Follow-up MRI at 28 + 3 weeks' gestation (Case 1) and at 1 postnatal year (Case 2) showed completely normal findings. Both children had normal psychomotor development and neurological examinations at 1 year of age. Incomplete rotation of the cerebellar vermis can be a physiological finding on early second-trimester fetal MRI examination and can simulate DWM or other forms of cerebellar hypoplasia. Embryologically, delayed permeabilization of Blake's pouch could account for the delayed vermian rotation. Follow-up imaging at a later gestational age is crucial to ensure that this condition is not over-reported and to avoid the potential risk of unnecessary pregnancy interruption. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.
Selective pathologies of the head and neck in children: a developmental perspective.

PubMed

Ozolek, John A

2009-09-01

The range of pathology seen in the head and neck region is truly amazing and to a large extent probably mirrors the complex signaling pathways and careful orchestration of events that occurs between the primordial germ layers during the development of this region. As is true in general for the entire discipline of pediatric pathology, the head and neck pathology within this age group is as diverse and different as its adult counterpart. Cases that come across the pediatric head and neck surgical pathology bench are more heavily weighted toward developmental and congenital lesions such as branchial cleft anomalies, thyroglossal duct cysts, ectopias, heterotopias, choristomas, and primitive tumors. Many congenital "benign" lesions can cause significant morbidity and even mortality if they compress the airway or other vital structures. Exciting investigations into the molecular embryology of craniofacial development have begun to shed light on the pathogenesis of craniofacial developmental lesions and syndromes. Much more investigation is needed, however, to intertwine aberrations in the molecular ontogeny and development of the head and neck regions to the represented pathology. This review will integrate traditional morphologic embryology with some of the recent advances in the molecular pathways of head and neck development followed by a discussion of a variety of developmental lesions finishing with tumors presumed to be derived from pluripotent/progenitor cells and tumors that show anomalous or aborted development.
FGF signaling induces mesoderm in the hemichordate Saccoglossus kowalevskii

PubMed Central

Green, Stephen A.; Norris, Rachael P.; Terasaki, Mark; Lowe, Christopher J.

2013-01-01

FGFs act in vertebrate mesoderm induction and also play key roles in early mesoderm formation in ascidians and amphioxus. However, in sea urchins initial characterizations of FGF function do not support a role in early mesoderm induction, making the ancestral roles of FGF signaling and mechanisms of mesoderm specification in deuterostomes unclear. In order to better characterize the evolution of mesoderm formation, we have examined the role of FGF signaling during mesoderm development in Saccoglossus kowalevskii, an experimentally tractable representative of hemichordates. We report the expression of an FGF ligand, fgf8/17/18, in ectoderm overlying sites of mesoderm specification within the archenteron endomesoderm. Embryological experiments demonstrate that mesoderm induction in the archenteron requires contact with ectoderm, and loss-of-function experiments indicate that both FGF ligand and receptor are necessary for mesoderm specification. fgf8/17/18 gain-of-function experiments establish that FGF8/17/18 is sufficient to induce mesoderm in adjacent endomesoderm. These experiments suggest that FGF signaling is necessary from the earliest stages of mesoderm specification and is required for all mesoderm development. Furthermore, they suggest that the archenteron is competent to form mesoderm or endoderm, and that FGF signaling from the ectoderm defines the location and amount of mesoderm. When considered in a comparative context, these data support a phylogenetically broad requirement for FGF8/17/18 signaling in mesoderm specification and suggest that FGF signaling played an ancestral role in deuterostome mesoderm formation. PMID:23344709
Current issues in medically assisted reproduction and genetics in Europe: research, clinical practice, ethics, legal issues and policy. European Society of Human Genetics and European Society of Human Reproduction and Embryology.

PubMed

Harper, Joyce C; Geraedts, Joep; Borry, Pascal; Cornel, Martina C; Dondorp, Wybo; Gianaroli, Luca; Harton, Gary; Milachich, Tanya; Kääriäinen, Helena; Liebaers, Inge; Morris, Michael; Sequeiros, Jorge; Sermon, Karen; Shenfield, Françoise; Skirton, Heather; Soini, Sirpa; Spits, Claudia; Veiga, Anna; Vermeesch, Joris Robert; Viville, Stéphane; de Wert, Guido; Macek, Milan

2013-11-01

In March 2005, a group of experts from the European Society of Human Genetics and European Society of Human Reproduction and Embryology met to discuss the interface between genetics and assisted reproductive technology (ART), and published an extended background paper, recommendations and two Editorials. Seven years later, in March 2012, a follow-up interdisciplinary workshop was held, involving representatives of both professional societies, including experts from the European Union Eurogentest2 Coordination Action Project. The main goal of this meeting was to discuss developments at the interface between clinical genetics and ARTs. As more genetic causes of reproductive failure are now recognised and an increasing number of patients undergo testing of their genome before conception, either in regular health care or in the context of direct-to-consumer testing, the need for genetic counselling and preimplantation genetic diagnosis (PGD) may increase. Preimplantation genetic screening (PGS) thus far does not have evidence from randomised clinical trials to substantiate that the technique is both effective and efficient. Whole-genome sequencing may create greater challenges both in the technological and interpretational domains, and requires further reflection about the ethics of genetic testing in ART and PGD/PGS. Diagnostic laboratories should be reporting their results according to internationally accepted accreditation standards (International Standards Organisation - ISO 15189). Further studies are needed in order to address issues related to the impact of ART on epigenetic reprogramming of the early embryo. The legal landscape regarding assisted reproduction is evolving but still remains very heterogeneous and often contradictory. The lack of legal harmonisation and uneven access to infertility treatment and PGD/PGS fosters considerable cross-border reproductive care in Europe and beyond. The aim of this paper is to complement previous publications and provide an update of selected topics that have evolved since 2005.
Developments in medical law in the United Kingdom in 2005 and 2006.

PubMed

Gertz, Renate; Harmon, Shawn; Laurie, Graeme; Pradella, Geoff

2006-06-01

This article highlights and summarises the key developments in medical law in the jurisdictions of the United Kingdom in 2005 and to April 2006. Topics are mental health and mental capacity, data protection, freedom of information and the impact on health data, the Human Tissue Act, genetic research databanks, Human Fertilisation and Embryology Act--Review of the legislation, consultations and related case law, developments in embryo and embryonic stem cell research, clinical trials and human subject research, medical futility, and physician assisted dying.
The future of the Human Fertilisation and Embryology Authority.

PubMed

English, Veronica

2013-04-01

The UK Government has proposed that the Human Fertilisation and Embryology Authority (HFEA) should be abolished and its functions transferred to the Care Quality Commission. This commentary explores the problems with this proposal and suggests that an independent review of how the HFEA carries out its functions and a subsequent reform of some of its practices represent a better option for the UK. Copyright © 2013 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Unraveling Pancreatic Segmentation.

PubMed

Renard, Yohann; de Mestier, Louis; Perez, Manuela; Avisse, Claude; Lévy, Philippe; Kianmanesh, Reza

2018-04-01

Limited pancreatic resections are increasingly performed, but the rate of postoperative fistula is higher than after classical resections. Pancreatic segmentation, anatomically and radiologically identifiable, may theoretically help the surgeon removing selected anatomical portions with their own segmental pancreatic duct and thus might decrease the postoperative fistula rate. We aimed at systematically and comprehensively reviewing the previously proposed pancreatic segmentations and discuss their relevance and limitations. PubMed database was searched for articles investigating pancreatic segmentation, including human or animal anatomy, and cadaveric or surgical studies. Overall, 47/99 articles were selected and grouped into 4 main hypotheses of pancreatic segmentation methodology: anatomic, vascular, embryologic and lymphatic. The head, body and tail segments are gross description without distinct borders. The arterial territories defined vascular segments and isolate an isthmic paucivascular area. The embryological theory relied on the fusion plans of the embryological buds. The lymphatic drainage pathways defined the lymphatic segmentation. These theories had differences, but converged toward separating the head and body/tail parts, and the anterior from posterior and inferior parts of the pancreatic head. The rate of postoperative fistula was not decreased when surgical resection was performed following any of these segmentation theories; hence, none of them appeared relevant enough to guide pancreatic transections. Current pancreatic segmentation theories do not enable defining anatomical-surgical pancreatic segments. Other approaches should be explored, in particular focusing on pancreatic ducts, through pancreatic ducts reconstructions and embryologic 3D modelization.
A history of fish immunology and vaccination I. The early days.

PubMed

Van Muiswinkel, Willem B

2008-10-01

This historic review describes the people that were involved in studying some aspect of fish immunology and vaccination from as early as 1854. Between 1850 and 1940, most scientists were looking at fish from the angle of comparative anatomy, embryology, physiology, taxonomy and fish diseases. Most publications from this early period are describing the morphology of blood cells and hemopoietic or lymphoid organs. The first publications on specific immune responses and vaccination of fish were found in the period 1935-1938. However, the immune mechanisms behind protective immunization were largely unknown in those days. In the period after 1940, the first researchers can be found devoting their whole career to fish immunology. This paper has been organized largely by individuals and not so much by accomplishments. It is not the intent of this review to evaluate the scientific merit of the work discussed, but to provide the reader with information that was - at least in part - lost to the scientific community. Publications from before 1940 or in languages other than English (e.g. Russian) are usually not found by today's database searches on the Internet.
Spondylocostal dysostosis associated with right-sided polythelia, right-sided rib deformity and meningocoele: Case report with review of literature

PubMed Central

Rai, Narendra; Thakur, Neha; Khan, Naheed Zin; Dwivedi, Akhilesh Dutt

2015-01-01

Spondylocostal dysostosis (SCD) is a rare anomaly of axial skeleton due to flawed embryological development. A newborn baby boy with right-sided polythelia, meningocoele, fan-like configuration of third and fourth rib, fused fifth and sixth rib and third thoracic hemivertebra was delivered to a second gravid mother by elective caesarean section. Baby was active, cried immediately after birth, had normal muscle tone and reflexes. He passed urine and meconium within 24 h of birth. Based on clinical examination and radiological picture, a diagnosis of SCD with meningocele with right-sided polythelia was made. Our case is the first SCD with polythelia and meningocele in newborn. SCD with right-sided polythelia and rib deformity with neural tube defect (NTD) may be due to a genetic defect with the culprit genes missing. Further genetic and embryological studies might find a link between right-sided rib defects, polythelia and NTD. PMID:26962344
Preliminary studies of enhanced contrast radiography in anatomy and embryology of insects with Elettra synchrotron light

NASA Astrophysics Data System (ADS)

Hönnicke, M. G.; Foerster, L. A.; Navarro-Silva, M. A.; Menk, R.-H.; Rigon, L.; Cusatis, C.

2005-08-01

Enhanced contrast X-ray imaging is achieved by exploiting the real part of the refraction index, which is responsible for the phase shifts, in addition to the imaginary part, which is responsible for the absorption. Such techniques are called X-ray phase contrast imaging. An analyzer-based X-ray phase contrast imaging set-up with Diffraction Enhanced Imaging processing (DEI) were used for preliminary studies in anatomy and embryology of insects. Parasitized stinkbug and moth eggs used as control agents of pests in vegetables and adult stinkbugs and mosquitoes ( Aedes aegypti) were used as samples. The experimental setup was mounted in the SYRMEP beamline at ELETTRA. Images were obtained using a high spatial resolution CCD detector (pixel size 14×14 μm 2) coupled with magnifying optics. Analyzer-based X-ray phase contrast images (PCI) and edge detection images show contrast and details not observed with conventional synchrotron radiography and open the possibility for future study in the embryonic development of insects.
A rare congenital extrahepatic portosystemic shunt affecting the inferior mesenteric vein, inferior vena cava, and left ovarian vein.

PubMed

Takeuchi, Hajime; Takeda, Yoko; Takahashi, Miyo; Hayashi, Shogo; Fukuzawa, Yoshitaka; Nakano, Takashi

2014-09-01

To observe a case of congenital extrahepatic portosystemic shunt and discuss it from the embryological and clinical viewpoints. An 85-year-old female cadaver was employed for a dissection course at Aichi Medical University in 2009. There was no evidence of liver cirrhosis macroscopically or microscopically. A portosystemic shunt was observed that involved communication between the inferior mesenteric vein, inferior vena cava (IVC), and left ovarian vein by a single Y-shaped shunt vessel. To the best of our knowledge, this is the first reported case of the above-mentioned three veins being connected by a single Y-shaped shunt vessel. Considering the other venous diameters, the shunt appeared to flow into the splenic vein and IVC. It cannot be denied that this shunt may have led to hepatic encephalopathy, although the shunt effect may have been minimal. Embryological development of IVC appears to occur close to the plexus of anastomosing vitelline veins, forming the portal vein.
[The meninges, an anatomical point of view].

PubMed

Sakka, L; Chazal, J

2005-03-01

The meninges correspond to an anatomical concept. For the morphologist, the microscopic organization, the hypothetical presence of a subdural space, the nature of the interface between the deep meningeal layer and the nervous parenchyma in the perivascular spaces are the central issues. For the clinician, dynamic aspects of cerebrospinal fluid flow, secretion, and resorption are essential factors with practical consequences in terms of disease and patient management. Comparative anatomy, embryology, and organogenesis provide an interesting perspective for the descriptive and functional anatomy of the meninges. Usually considered as protective membranes, the meninges play a prominent role in the development and maintenance of the central nervous system. The meninges are in constant evolution, from their formation to senescence. The meninges present three layers in children and adults: the dura mater, the arachnoid and the pia mater. The cerebrospinal fluid is secreted by the choroid plexuses, flows through the ventricles and the subarachnoid space, and is absorbed by arachnoid granulations. Other sites of secretion and resorption are suggested by comparative anatomy and human embryology and organogenesis.
Construction and application of 3D model sequence to illustrate the development of the human embryo

NASA Astrophysics Data System (ADS)

Mizuta, Shinobu; Kakusho, Koh; Minekura, Yutaka; Minoh, Michihiko; Nakatsu, Tomoko; Shiota, Kohei

2002-05-01

Embryology is one of the basic subjects in medical education, to learn the process of human development especially from fertilization to birth. The shape deformation in the development of human embryo is one of the most important points to be comprehended, but it is difficult to illustrate the deformation by texts, 2D drawings, photographs and so on, because it is extremely complicated. The purpose of our research is to construct a 3D model sequence to illustrate the deformation of human embryo, and to make the model sequence into the teaching materials for medical education. Firstly, 3D images of the specimens of human embryo were acquired using MR microscopy. Next, an initial 3D model sequence was manually modified by comparing with the features of the acquired images under the supervision of medical doctors, because the images were influenced not only by the noise or limitation of resolution in MR image acquisition, but also by the variation of shape depending on the difference of subject. Using the constructed 3D model sequence, CG animations and an interactive VRML system were composed as the teaching materials for embryology. These materials were quite helpful to understand the shape deformation compared with the conventional materials.
Dental twinning anomalies: the nomenclature enigma.

PubMed

Killian, C M; Croll, T P

1990-07-01

Dental twinning results from abnormal events in the embryologic development of teeth. This paper describes the impossibility of assigning precise diagnostic terms, such as germination, fusion, macrodontia, and concrescence, to dental twinning anomalies because the entire course of odontogenesis cannot be witnessed. Traditional nomenclature is reviewed and seven cases that exemplify the principle are presented. Modification of nomenclature to describe dental twinning defects is suggested.
Learning to Lead: Self- and Peer Evaluation of Team Leaders in the Human Structure Didactic Block

ERIC Educational Resources Information Center

Chen, Laura P.; Gregory, Jeremy K.; Camp, Christopher L.; Juskewitch, Justin E.; Pawlina, Wojciech; Lachman, Nirusha

2009-01-01

Increasing emphasis on leadership in medical education has created a need for developing accurate evaluations of team leaders. Our study aimed to compare the accuracy of self- and peer evaluation of student leaders in the first-year Human Structure block (integrated gross anatomy, embryology, and radiology). Forty-nine first-year medical students…
[Head and neck paragangliomas. Embryological origin and anatomical characteristics: topographic distribution and vascularization pattern].

PubMed

Carretero González, José; Blanco Pérez, Pedro; Vázquez Osorio, María Teresa; Benito González, Fernando; Sañudo Tejedo, José Ramón

2009-02-01

Paragangliomas are tumors that arise in the extraadrenal paraganglia and result from migration of neural crest cells during embryonic development. Based on their anatomical distribution, innervation and microscopic structure, these tumors can be classified into interrelated families: branchiomeric paraganglia (related to the branchial clefts and arches), intravagal, aortic-sympathetic and visceral-autonomic. Head and neck paragangliomas belong mainly to the first two of these families. The present article is divided into two parts. The first part reviews the embryological origin of these tumors. Special emphasis is placed on the process of neurulation or neural tube formation, neurosegmentation (with a summary of the mechanisms involved in the initial segmentation of the neural tube and of the hindbrain and spinal medulla), and the development of the sensory placodes and secondary inductions in the cranial region. Subsequently, the neural crest is analyzed, with special attention paid to the cranial neural crest. The embryonogenesis of paragangliomas is also described. The second part describes the topographical distribution of head and neck paragangliomas according to their localization: jugulotympanic, orbit, intercarotid, subclavian and laryngeal. The embryonogenesis and most important anatomical characteristics are described for each type.
Glycan antagonists and inhibitors: a fount for drug discovery.

PubMed

Brown, Jillian R; Crawford, Brett E; Esko, Jeffrey D

2007-01-01

Glycans, the carbohydrate chains of glycoproteins, proteoglycans, and glycolipids, represent a relatively unexploited area for drug development compared with other macromolecules. This review describes the major classes of glycans synthesized by animal cells, their mode of assembly, and available inhibitors for blocking their biosynthesis and function. Many of these agents have proven useful for studying the biological activities of glycans in isolated cells, during embryological development, and in physiology. Some are being used to develop drugs for treating metabolic disorders, cancer, and infection, suggesting that glycans are excellent targets for future drug development.
The ventricular system of the brain: a comprehensive review of its history, anatomy, histology, embryology, and surgical considerations.

PubMed

Mortazavi, M M; Adeeb, N; Griessenauer, C J; Sheikh, H; Shahidi, S; Tubbs, R I; Tubbs, R S

2014-01-01

The cerebral ventricles have been recognized since ancient medical history. Their true function started to be realized more than a thousand years later. Their anatomy and function are extremely important in the neurosurgical panorama. The literature was searched for articles and textbooks of different topics related to the history, anatomy, physiology, histology, embryology and surgical considerations of the brain ventricles. Herein, we summarize the literature about the cerebral ventricular system.
[The scientific works of the teachers of human anatomy in the "Université Libre de Bruxelles" (ULB)].

PubMed

Louryan, S

2014-06-01

The "Université Libre de Bruxelles" was founded in 1834. Between this year and 1904, the teachers of human anatomy were essentially clinicians and surgeons. Their works were mainly practical. Until 1904 (arrival of Albert Brachet) since present, the researches of the anatomical laboratory were devoted to embryology, and included the beginning of causal embryology. More recently, biomechanics appeared in the field of activity of the laboratory. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Revised guidelines for good practice in IVF laboratories (2015).

PubMed

De los Santos, Maria José; Apter, Susanna; Coticchio, Giovanni; Debrock, Sophie; Lundin, Kersti; Plancha, Carlos E; Prados, Fernando; Rienzi, Laura; Verheyen, Greta; Woodward, Bryan; Vermeulen, Nathalie

2016-04-01

Which recommendations can be provided by the European Society of Human Reproduction and Embryology Special Interest Group (ESHRE SIG) Embryology to support laboratory specialists in the organization and management of IVF laboratories and the optimization of IVF patient care? Structured in 13 sections, the guideline development group formulated recommendations for good practice in the organization and management of IVF laboratories, and for good practice of the specific procedures performed within the IVF laboratory. NA. The guideline was produced by a group of 10 embryologists representing different European countries, settings and levels of expertise. The group evaluated the document of 2008, and based on this assessment, each group member rewrote one or more sections. Two 2-day meetings were organized during which each of the recommendations was discussed and rewritten until consensus within the guideline group was reached. After finalizing the draft, the members of the ESHRE SIG embryology were invited to review the guideline. NA. The guideline provides recommendations on the general organization of an IVF laboratory (staffing and direction, quality management, laboratory safety), and on the specific aspects of the procedures performed in IVF laboratories (Identification of patients and traceability of their reproductive cells, consumables, handling of biological material, oocyte retrieval, sperm preparation, insemination of oocytes, scoring for fertilization, embryo culture and transfer, and cryopreservation). A last section provides recommendations regarding an Emergency plan for IVF laboratories. Evidence on most of the issues described is scarce, and therefore it was decided not to perform a formal search for and assessment of scientific evidence. However, recommendations published in the EUTCD and relevant and recent documents, manuals and consensus papers were taken into account when formulating the recommendations. Despite the limitations, the guideline group is confident that this document will be helpful to directors and managers involved in the management and organization of IVF laboratories, but also to embryologists and laboratory technicians performing daily tasks. The guideline was developed and funded by ESHRE, covering expenses associated with the guideline meetings. The guideline group members did not receive payment. Dr Coticchio reports speaker's fees from IBSA and Cook, outside the submitted work; Dr Lundin reports grants from Vitrolife, personal fees from Merck Serono, non-financial support from Unisense, outside the submitted work; Dr. Rienzi reports personal fees from Merck Serono, personal fees from MSD, grants from GFI, outside the submitted work; the other authors had nothing to disclose. NA. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Cox-1 Suppression and Follicle Depletion in the Etiology of Menopause- Associated Ovarian Cancer

DTIC Science & Technology

2008-04-01

follicular function (2). Most oocytes are progressively lost by atresia, or apoptosis (3), and the ovary may develop a number of atrophic features...the risk of ovarian epithelial cancers, by far the most predominant form (14), and cause growth inhibition and apoptosis in ovarian cancer cell lines...1990;4:390-400. 8. Mintz B. Embryological development of primordial germ-cells in the mouse: influence of a new mutation, Wj. J Embryol Exp
[Cyto-embryologic investigation of super dwarf wheat grown on board of the Mir orbital complex

NASA Technical Reports Server (NTRS)

Veselova, T. D.; Il'ina, G. M.; Dzhaliova, Kh Kh; Levinskikh, M. A.; Sychev, V. N.; Salisbury, F. B.; Campbell, W. F.

1999-01-01

The cytoembryologic analysis of wet and dry samples of super dwarf wheat cultivated in greenhouse SVET aboard the MIR station over the whole cycle of vegetation was made with the use of light microscopy. Characteristic features of wheat development in space flight are plentiful early tillering, and formation and rapid growth of side shoots. Elementary spikelets in the composite head were more numerous but the top spikelets were rudimentary and, therefore, the ripe head contained less of these spikelets as compared with the ground controls (9-13 and 14, respectively). The number of florets in a spike was also higher reaching 14-16 vs. 7-8 in the control. Typically, no more than 4 to 5 florets vs. 3 in the control were fully differentiated while the others died off earlier in development. The fact that there were no caryopses found in the flight crop is explained by absolute male sterility appearing at different stages of staminal development: before archesporium formation, on the stage of differentiated archesporium, during meiosis, on the stage of microspores or uninucleate "pollen". The female generative system developed mainly without abnormalities. An assumption was made that elevated ethylene concentrations in the MIR atmosphere at the time of the wheat experiment were the cause for abnormal development of the male generative system which led to barrenness of the super dwarf wheat crop.
Obstructed uteri with a cervix and vagina.

PubMed

Wright, Kelly Nicole; Okpala, Ogochukwu; Laufer, Marc R

2011-01-01

To describe a rare anomaly of the female reproductive tract and review the embryology associated with the defect. Case report and review of the literature. Major academic medical center. A 14-year-old girl with two hemiuteri lacking any communication with a single normal midline cervix and vagina. Diagnostic laparoscopy with chromopertubation to identify the anomaly and subsequent bilateral supracervical hemihysterectomies. Incidence, pathogenesis, fertility implications, and treatment options for patients with congenital defects in the upper vagina, cervix, and uterus. Based on classic embryology, the lower vagina forms from the urogenital sinus while the upper vagina, cervix, and uterus form from the müllerian ducts. If a cervix is present, then the upper vagina and uterus are also usually present and should communicate. This anomaly cannot be fully explained by traditional embryologic developmental theory. It is likely that an insult occurred between 9 weeks, when the uterovaginal canal is formed, and 12 weeks, when the müllerian ducts fuse. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
American Catholic Responses to Evolutionary Theories, 1845-75

DTIC Science & Technology

1990-01-01

embryology invalid, observing that even if the embryos of higher animls pass through lower stages of life as they develop, there was no possibility...Its Constitution, Tendencies, and Destiny , which he published in 1865 but which was essentially an elaboration of his political thought circa 1843...between Jan. - Feb. 1865). _ The American Republic: Its Constitution, Tendencies and Destiny . New York: 1865; reprinted in Masterworks of Literature
Prenatal cranial ossification of the humpback whale (Megaptera novaeangliae).

PubMed

Hampe, Oliver; Franke, Helena; Hipsley, Christy A; Kardjilov, Nikolay; Müller, Johannes

2015-05-01

Being descendants of small terrestrial ungulate mammals, whales underwent enormous transformations during their evolutionary history, that is, extensive changes in anatomy, physiology, and behavior were evolved during secondary adaptations to life in water. However, still only little is known about whale ontogenetic development, which help to identify the timing and sequence of critical evolutionary events, such as modification of the cetacean ear. This is particularly true for baleen whales (Mysticeti), the group including the humpback whale Megaptera novaeangliae. We use high-resolution X-ray computed tomography to reinvestigate humpback whale fetuses from the Kükenthal collection at the Museum für Naturkunde, Berlin, thus, extending historic descriptions of their skeletogenesis and providing for the first time sequences of cranial ossification for this species. Principally, the ossification sequence of prenatal Megaptera follows a typical mammalian pattern with the anterior dermal bones being the first ossifying elements in the skull, starting with the dentary. In contrast to other mammals, the ectotympanic bone ossifies at an early stage. Alveolar structure can be observed in both the maxillae and dentaries in these early prenatal specimens but evidence for teeth is lacking. Although the possibility of obtaining new embryological material is unlikely due to conservation issues, our study shows that reexamination of existing specimens employing new technologies still holds promise for filling gaps in our knowledge of whale evolution and ontogeny. © 2015 Wiley Periodicals, Inc.
Becoming organisms: the organisation of development and the development of organisation.

PubMed

de la Rosa, Laura Nuño

2010-01-01

Despite the radical importance of embryology in the development of organicism, developmental biology remains philosophically underexplored as a theoretical and empirical resource to clarify the nature of organisms. This paper discusses how embryology can help develop the organisational definition of the organism as a differentiated, functionally integrated, and autonomous system. I distinguish two conceptions of development in the organisational tradition that yield two different conceptions of the organism: the life-history view claims that organisms can be considered as such during their whole ontogeny; the constitutive view distinguishes two periods in the life history, a period of generation and a period of self-maintenance of a constitutive organisation. Arguing in favour of the constitutive view, it will be claimed that the organisational criteria for the definition of organism (i.e., differentiation, functional integration, and autonomy) can only be applied to the developmental system when it has entered the period of self-maintenance of a constitutive organisation. Under the light of current research in developmental biology, it is possible to make explicit how organisms come to be as organisms. To this end, I explore key ontogenetic events that help us clarify the core aspects of animal organisation and allow us to identify the developmental stage that marks the ontological transition between an organism in potency and an organism in actuality. The structure of this ontogenetic unfolding parallels the conceptual structure of the very notion of organism; the generation of the being of a particular organism parallels its definition.

Mechanical control of tissue and organ development

PubMed Central

Mammoto, Tadanori; Ingber, Donald E.

2010-01-01

Many genes and molecules that drive tissue patterning during organogenesis and tissue regeneration have been discovered. Yet, we still lack a full understanding of how these chemical cues induce the formation of living tissues with their unique shapes and material properties. Here, we review work based on the convergence of physics, engineering and biology that suggests that mechanical forces generated by living cells are as crucial as genes and chemical signals for the control of embryological development, morphogenesis and tissue patterning. PMID:20388652
On recent advances in human engineering Provocative trends in embryology, genetics, and regenerative medicine.

PubMed

Anton, Roman

2016-01-01

Advances in embryology, genetics, and regenerative medicine regularly attract attention from scientists, scholars, journalists, and policymakers, yet implications of these advances may be broader than commonly supposed. Laboratories culturing human embryos, editing human genes, and creating human-animal chimeras have been working along lines that are now becoming intertwined. Embryogenic methods are weaving traditional in vivo and in vitro distinctions into a new "in vivitro" (in life in glass) fabric. These and other methods known to be in use or thought to be in development promise soon to bring society to startling choices and discomfiting predicaments, all in a global effort to supply reliably rejuvenating stem cells, to grow immunologically non-provocative replacement organs, and to prevent, treat, cure, or even someday eradicate diseases having genetic or epigenetic mechanisms. With humanity's human-engineering era now begun, procedural prohibitions, funding restrictions, institutional controls, and transparency rules are proving ineffective, and business incentives are migrating into the most basic life-sciences inquiries, wherein lie huge biomedical potentials and bioethical risks. Rights, health, and heritage are coming into play with bioethical presumptions and formal protections urgently needing reassessment.
Congenital lesions of epithelial origin.

PubMed

Hills, Susannah E; Maddalozzo, John

2015-02-01

Defects of embryologic development give rise to a variety of congenital lesions arising from the epithelium and are among the most common congenital lesions of the head and neck in the pediatric population. This article presents several congenital lesions of epithelial origin, including congenital midline cervical cleft, pilomatrixoma, dermoid, foregut duplication cysts, and preauricular sinuses and pits. In addition, the management of these lesions is reviewed. Copyright © 2015 Elsevier Inc. All rights reserved.
Mathematics Ab Ovo: Hans Driesch and Entwicklungsmechanik.

PubMed

Priven, Silvia Waisse; Alfonso-Goldfarb, Ana M

2009-01-01

One of the factors leading to the creation of embryology as a modern discipline at the end of the 19th century was Wilhelm Roux's formulation of the program of Entwicklungsmechanik (developmental mechanics). A look into the work of Hans Driesch, an equal contributor to developmental mechanics, may shed further light on this process. For Roux, developmental mechanics was an anatomical science, but for Driesch it was associated with a mathematical and physical approach to the natural world. Likewise, Roux used the concept of mechanics as an analogy, but Driesch used it literally. Driesch's generation had been trained in a pedagogic context that emphasized mathematics and physics, which may explain why he went a step further than Roux to state that a true "mechanics" of development required the reduction of morphogenetic problems to the known laws of physics. It is argued here that this difference in background is behind the enthusiastic adoption and further development of Roux's program by Driesch's generation, a generation that conceived Entwicklungsmechanik to be the reduction of embryological processes to "the laws of matter in motion." This same mathematical and physical mindset would underscore Driesch's later construction of entelechy as a regulating factor in embryogenesis, through mathematical analysis grounded on the notion of mathematical functions.
Sediment porewater toxicity assessment studies in the vicinity of offshore oil and gas production platforms in the Gulf of Mexico

USGS Publications Warehouse

Carr, R.S.; Chapman, D.C.; Presley, B.J.; Biedenbach, J.M.; Robertson, L.; Boothe, P.; Kilada, R.; Wade, T.; Montagna, P.

1996-01-01

As part of a multidisciplinary program to assess the potential long-term impacts of offshore oil and gas exploration and production activities in the Gulf of Mexico, sediment chemical analyses and porewater toxicity tests were conducted in the vicinity of five offshore platforms. Based on data from sea urchin fertilization and embryological development assays, toxicity was observed near four of the five platforms sampled; the majority of the toxic samples were collected within 150 m of a platform. There was excellent agreement among the results of porewater tests with three different species (sea urchin embryological development, polychaete reproduction, and copepod nauplii survival). The sediment concentrations of several metals were well in excess of sediment quality assessment guidelines at a number of stations, and good agreement was observed between predicted and observed toxicity. Porewater metal concentrations compared with EC50, LOEC, and NOEC values generated for water-only exposures indicated that the porewater concentrations for several metals were high enough to account for the observed toxicity. Results of these studies utilizing highly sensitive toxicity tests suggest that the contaminant-induced impacts from offshore platforms are limited to a localized area in the immediate vicinity of the platforms.
Mice embryology: a microscopic overview.

PubMed

Salvadori, Maria Letícia Baptista; Lessa, Thais Borges; Russo, Fabiele Baldino; Fernandes, Renata Avancini; Kfoury, José Roberto; Braga, Patricia Cristina Baleeiro Beltrão; Miglino, Maria Angélica

2012-10-01

In this work, we studied the embryology of mice of 12, 14, and 18 days of gestation by gross observation, light microscopy, and scanning electron microscopy. Grossly, the embryos of 12 days were observed in C-shaped region of the brain, eye pigmentation of the retina, first, second, and third pharyngeal arches gill pit nasal region on the fourth ventricle brain, cervical curvature, heart, liver, limb bud thoracic, spinal cord, tail, umbilical cord, and place of the mesonephric ridge. Microscopically, the liver, cardiovascular system and spinal cord were observed. In the embryo of 14 days, we observed structures that make up the liver and heart. At 18 days of gestation fetuses, it was noted the presence of eyes, mouth, and nose in the cephalic region, chest and pelvic region with the presence of well-developed limbs, umbilical cord, and placenta. Scanning electron microscopy in 18 days of gestation fetuses evidenced head, eyes closed eyelids, nose, vibrissae, forelimb, heart, lung, kidney, liver, small bowel, diaphragm, and part of the spine. The results obtained in this work describe the internal and external morphology of mice, provided by an integration of techniques and review of the morphological knowledge of the embryonic development of this species, as this animal is of great importance to scientific studies. Copyright © 2012 Wiley Periodicals, Inc.
Marine invertebrates, model organisms, and the modern synthesis: epistemic values, evo-devo, and exclusion.

PubMed

Love, Alan C

2009-03-01

A central reason that undergirds the significance of evo-devo is the claim that development was left out of the Modern synthesis. This claim turns out to be quite complicated, both in terms of whether development was genuinely excluded and how to understand the different kinds of embryological research that might have contributed. The present paper reevaluates this central claim by focusing on the practice of model organism choice. Through a survey of examples utilized in the literature of the Modern synthesis, I identify a previously overlooked feature: exclusion of research on marine invertebrates. Understanding the import of this pattern requires interpreting it in terms of two epistemic values operating in biological research: theoretical generality and explanatory completeness. In tandem, these values clarify and enhance the significance of this exclusion. The absence of marine invertebrates implied both a lack of generality in the resulting theory and a lack of completeness with respect to particular evolutionary problems, such as evolvability and the origin of novelty. These problems were salient to embryological researchers aware of the variation and diversity of larval forms in marine invertebrates. In closing, I apply this analysis to model organism choice in evo-devo and discuss its relevance for an extended evolutionary synthesis.
Evaluation of a modified team based learning method for teaching general embryology to 1st year medical graduate students.

PubMed

Shankar, Nachiket; Roopa, R

2009-01-01

To encourage student participation in the learning process, the authors introduced a modified team based learning (TBL) method to cover two general embryology topics in the 1st year MBBS curriculum. The aim of this study was to evaluate students' perception of this method vis-à-vis the lecture method of teaching. A questionnaire was used to survey and evaluate the perceptions of 1st year MBBS students at the Department of Anatomy at our medical college in India. A total of eight classes were allotted to cover General Embryology. Six of these classes were conducted using the traditional didactic lecture method. Two topics were covered using the modified TBL method. Five teams of students were constituted, and each team was given handouts which contained basic factual material, four clinical case histories, and previous university exam questions from the topic. On the day of the session, these were discussed in the presence of the faculty facilitator. Students evaluated these sessions through a questionnaire. A majority of students felt that the modified TBL sessions were better at fulfilling learning objectives (46 students, 85%), enabled better understanding (43 students, 79%), were more interesting (43 students, 81%), ensured greater student participation (51 students, 94%) and involved greater effort on the part of students (53 students, 98%), as compared to traditional teaching methods. Most of the students (43 students, 79%) opined that more such sessions should be organized in the future. Responses from students show that the modified TBL classes could be utilized judiciously along with the traditional didactic lectures for teaching embryology.
A comparison of the Cook single lumen immature ovum IVM needle to the Steiner-Tan pseudo double lumen flushing needle for oocyte retrieval for IVM.

PubMed

Rose, B I; Laky, D

2013-06-01

This study compared the impact of using the Steiner-Tan pseudo double lumen needle for antral follicle oocyte retrieval to using a conventional non-flushing needle. The Steiner-Tan needle has a much smaller dead space than the needles commonly used for IVM oocyte retrievals. This was a retrospective cohort study. The patient population was determined by the time period in which a patient underwent IVM in a single physician's IVF practice. The following data was abstracted from clinical and embryology records: oocytes retrieved, oocytes matured, early maturing oocytes, oocytes fertilized, embryo quality measures, retrieval time, needle punctures, clot formation, and clinical pregnancy rate. The Steiner-Tan needle did not increase the number of oocytes retrieved. It also did not increase the time required for retrieval. However, flushing of antral follicles significantly decreased clot formation in fluid aspirates. Use of the Steiner-Tan needle also significantly decreased the number of vaginal needle punctures during each case. There was a trend toward improved embryo quality, but statistical power was inadequate to show a difference. The primary benefit of the Steiner-Tan needle was on the embryological aspects of IVM. Decreased blood and blood clots in the aspirates made an IVM retrieval more like conventional IVF for the embryologist. The patient also experienced less tissue trauma without increasing anesthesia or surgical time. There was no improvement in the number of oocytes retrieved, but based on the results, we hypothesized that oocytes were more commonly retrieved from slightly large follicles than when using a routine needle.
Sex determination and disorders of sex development according to the revised nomenclature and classification in 46,XX individuals.

PubMed

Kousta, Eleni; Papathanasiou, Asteroula; Skordis, Nicos

2010-01-01

There have been considerable advances concerning understanding of the early and later stages of ovarian development; a number of genes have been implicated and their mutations have been associated with developmental abnormalities. The most important genes controlling the initial phase of gonadal development, identical in females and males, are Wilms' tumor suppressor 1 (WT1) and steroidogenic factor 1 (SF1). Four genes are likely to be involved in the subsequent stages of ovarian development (WNT4, DAX1, FOXL2 and RSPO1), but none is yet proven to be the ovarian determining factor. Changes in nomenclature and classification were recently proposed in order to incorporate genetic advances and substitute gender-based diagnostic labels in terminology. The term "disorders of sex development" (DSD) is proposed to substitute the previous term "intersex disorders". Three main categories have been used to describe DSD in the 46,XX individual: 1) disorders of gonadal (ovarian) development: ovotesticular DSD, previously named true hermaphroditism, testicular DSD, previously named XX males, and gonadal dysgenesis; 2) disorders related to androgen excess (congenital adrenal hyperplasia, aromatase deficiency and P450 oxidoreductase deficiency); and 3) other rare disorders. In this mini-review, recent advances concerning development of the genital system in 46,XX individuals and related abnormalities are discussed. Basic embryology of the ovary and molecular pathways determining ovarian development are reviewed, focusing on mutations disrupting normal ovarian development. Disorders of sex development according to the revised nomenclature and classification in 46,XX individuals are summarized, including genetic progress in the field.
Branchial cysts within the parotid salivary gland

PubMed Central

2012-01-01

Cystic lesions within the parotid gland are uncommon and clinically they are frequently misdiagnosed as tumours. Many theories have been proposed as to their embryological origin. A 20-year retrospective review was undertaken of all pathological codes (SNOMED) of all of patients presenting with any parotid lesions requiring surgery. After analysis seven subjects were found to have histopathologically proven parotid branchial cysts in the absence of HIV infection and those patients are the aim of this review. Four of the most common embryological theories are also discussed with regard to these cases, as are their management. PMID:22607735
[The mark of envy: metaphysics and embryology according to Descartes].

PubMed

Gaudemard, Lynda

2012-01-01

This paper explores the interaction between medicine and metaphysics in modern natural philosophy and especially in Descartes' philosophy. I argue that Descartes hypothetical account of birthmarks in connection with his embryology provides an argumentative proof of the metaphysical necessity of a substantial union between mind and body, which however does not threaten his doctrine of the real distinction between these two substances. It would appear that his argument relies on a temporal conception of alethic modalities and provides a new answer to Henricus Regius who in 1641 claimed that, for Descartes, the human being is an ensper accidens.
Diagnostic Approach to Pediatric Spine Disorders.

PubMed

Rossi, Andrea; Martinetti, Carola; Morana, Giovanni; Severino, Mariasavina; Tortora, Domenico

2016-08-01

Understanding the developmental features of the pediatric spine and spinal cord, including embryologic steps and subsequent growth of the osteocartilaginous spine and contents is necessary for interpretation of the pathologic events that may affect the pediatric spine. MR imaging plays a crucial role in the diagnostic evaluation of patients suspected of harboring spinal abnormalities, whereas computed tomography and ultrasonography play a more limited, complementary role. This article discusses the embryologic and developmental anatomy features of the spine and spinal cord, together with some technical points and pitfalls, and the most common indications for pediatric spinal MR imaging. Copyright © 2016 Elsevier Inc. All rights reserved.
Vertebrate limb development: moving from classical morphogen gradients to an integrated 4-dimensional patterning system.

PubMed

Bénazet, Jean-Denis; Zeller, Rolf

2009-10-01

A wealth of classical embryological manipulation experiments taking mainly advantage of the chicken limb buds identified the apical ectodermal ridge (AER) and the zone of polarizing activity (ZPA) as the respective ectodermal and mesenchymal key signaling centers coordinating proximodistal (PD) and anteroposterior (AP) limb axis development. These experiments inspired Wolpert's French flag model, which is a classic among morphogen gradient models. Subsequent molecular and genetic analysis in the mouse identified retinoic acid as proximal signal, and fibroblast growth factors (FGFs) and sonic hedgehog (SHH) as the essential instructive signals produced by AER and ZPA, respectively. Recent studies provide good evidence that progenitors are specified early with respect to their PD and AP fates and that morpho-regulatory signaling is also required for subsequent proliferative expansion of the specified progenitor pools. The determination of particular fates seems to occur rather late and depends on additional signals such as bone morphogenetic proteins (BMPs), which indicates that cells integrate signaling inputs over time and space. The coordinate regulation of PD and AP axis patterning is controlled by an epithelial-mesenchymal feedback signaling system, in which transcriptional regulation of the BMP antagonist Gremlin1 integrates inputs from the BMP, SHH, and FGF pathways. Vertebrate limb-bud development is controlled by a 4-dimensional (4D) patterning system integrating positive and negative regulatory feedback loops, rather than thresholds set by morphogen gradients.
EXPERIMENTAL STUDIES ON EMBRYOGENESIS IN HYDROZOANS (TRACHYLINA AND SIPHONOPHORA) WITH DIRECT DEVELOPMENT.

PubMed

Freeman, Gary

1983-12-01

The normal embryology of the trachymedusa Aglantha digitale and the siphonophores Nanomia cara and Muggiaea atlantica is described. Marking experiments on these embryos indicate that the site of first cleavage initiation corresponds to the oral pole of the oral-aboral axis. In Muggiaea the plane of the first cleavage corresponds to the plane of bilateral symmetry. Experiments in which presumptive aboral and oral regions are isolated from these embryos at different stages of development indicate that there is an early determination of different regions along this axis. Only the oral region of the Muggiaea embryo has the ability to regulate. These eggs have a pronounced centrolecithal organization. As a consequence of cleavage, the outer ectoplasmic layer of the egg ends up in the cells that form the ectoderm, while the inner or endoplasmic region of the egg ends up in the cells that form the endoderm. Experimentally created fragments of fertilized eggs that contain only ectoplasm differentiate to form an unorganized ectodermal cell mass, indicating that endoplasm is necessary in order to differentiate endoderm. The process of embryogenesis in these animals and the developmental mechanisms they use are very different from those used by hydrozoans with indirect development. These embryos use a suite of developmental mechanisms which are very similar to those used by ctenophores. The significance of this similarity is discussed.
Uterus didelphys associated with unilateral imperforate vagina.

PubMed

Gilliland, B; Dyck, F

1976-07-01

Two cases of uterus didelphys associated with unilateral imperforate vagina are reported with a review of the literature. In all cases investigated, ipsilateral renal agenesis was found on the affected side. A summary of the embryologic development of the female reproductive tract is included, as well as a possible explanation for this rare anomaly. The authors describe their proposed method of management to achieve freedom from symptoms and maintenance of a relatively intact reproductive tract.
Diagnosis of pediatric gastric, small-bowel and colonic volvulus.

PubMed

Garel, Charles; Blouet, Marie; Belloy, Frederique; Petit, Thierry; Pelage, Jean-Pierre

2016-01-01

Digestive volvulus affects the stomach, small bowel and mobile segments of the colon and often has a developmental cause. Reference radiologic examinations include upper gastrointestinal contrast series for gastric volvulus, possibly with ultrasonography for small-bowel volvulus, and contrast enema for colonic volvulus. Treatment is usually surgical. This pictorial essay describes the embryological development and discusses the clinical and radiologic presentation of volvulus, depending on location, and details the appropriate radiologic examinations.
Developmental and Genetic Aspects of Clefting Disorders: A Clinical Approach

PubMed Central

Hanson, James W.; Thomson, Elizabeth J.; Muilrnnuth, Snn V.; Sandra, Alexander; Coan, Joan M.; Lipcamon, Larry D.; Hill, Ed

1990-01-01

This demonstration shows an interactive videodisc program that teaches the basic embryology of craniofacial development, the developmental and genetic aspects of orofacial clefts, and the process of diagnosing a patient with a clefting disorder. This program is designed for medical students, residents, and fellows in Pediatrics and Otolaryngology. It will also be of interest to members of cleft lip/palate teams. Imagesp1020-ap1021-ap1021-bp1021-c
Malformations of Cortical Development and Epilepsy

PubMed Central

Barkovich, A. James; Dobyns, William B.; Guerrini, Renzo

2015-01-01

Malformations of cortical development (MCDs) are an important cause of epilepsy and an extremely interesting group of disorders from the perspective of brain development and its perturbations. Many new MCDs have been described in recent years as a result of improvements in imaging, genetic testing, and understanding of the effects of mutations on the ability of their protein products to correctly function within the molecular pathways by which the brain functions. In this review, most of the major MCDs are reviewed from a clinical, embryological, and genetic perspective. The most recent literature regarding clinical diagnosis, mechanisms of development, and future paths of research are discussed. PMID:25934463
Study of a fetal brain affected by a severe form of tyrosine hydroxylase deficiency, a rare cause of early parkinsonism.

PubMed

Tristán-Noguero, Alba; Díez, Héctor; Jou, Cristina; Pineda, Mercè; Ormazábal, Aida; Sánchez, Aurora; Artuch, Rafael; Garcia-Cazorla, Àngels

2016-06-01

Tyrosine hydroxylase (TH) deficiency is an inborn error of dopamine synthesis. Two clinical phenotypes have been described. The THD "B" phenotype produces a severe encephalopathy of early-onset with sub-optimal L-Dopa response, whereas the "A" phenotype has a better L-Dopa response and outcome. The objective of the study is to describe the expression of key synaptic proteins and neurodevelopmental markers in a fetal brain of THD "B" phenotype. The brain of a 16-week-old miscarried human fetus was dissected in different brain areas and frozen until the analysis. TH gene study revealed the p.R328W/p.T399M mutations, the same mutations that produced a B phenotype in her sister. After protein extraction, western blot analyses were performed to assess protein expression. The results were compared to an age-matched control. We observed a decreased expression in TH and in other dopaminergic proteins, such as VMAT 1 and 2 and dopamine receptors, especially D2DR. GABAergic and glutamatergic proteins such as GABA VT, NMDAR1 and calbindin were also altered. Developmental markers for synapses, axons and dendrites were decreased whereas markers of neuronal volume were preserved. Although this is an isolated case, this brain sample is unique and corresponds to the first reported study of a THD brain. It provides interesting information about the influence of dopamine as a regulator of other neurotransmitter systems, brain development and movement disorders with origin at the embryological state. This study could also contribute to a better understanding of the pathophysiology of THD at early fetal stages.

The evolution of the dorsal thalamus of jawed vertebrates, including mammals: cladistic analysis and a new hypothesis.

PubMed

Butler, A B

1994-01-01

The evolution of the dorsal thalamus in various vertebrate lineages of jawed vertebrates has been an enigma, partly due to two prevalent misconceptions: the belief that the multitude of nuclei in the dorsal thalamus of mammals could be meaningfully compared neither with the relatively few nuclei in the dorsal thalamus of anamniotes nor with the intermediate number of dorsal thalamic nuclei of other amniotes and a definition of the dorsal thalamus that too narrowly focused on the features of the dorsal thalamus of mammals. The cladistic analysis carried out here allows us to recognize which features are plesiomorphic and which apomorphic for the dorsal thalamus of jawed vertebrates and to then reconstruct the major changes that have occurred in the dorsal thalamus over evolution. Embryological data examined in the context of Von Baerian theory (embryos of later-descendant species resemble the embryos of earlier-descendant species to the point of their divergence) supports a new 'Dual Elaboration Hypothesis' of dorsal thalamic evolution generated from this cladistic analysis. From the morphotype for an early stage in the embryological development of the dorsal thalamus of jawed vertebrates, the divergent, sequential stages of the development of the dorsal thalamus are derived for each major radiation and compared. The new hypothesis holds that the dorsal thalamus comprises two basic divisions--the collothalamus and the lemnothalamus--that receive their predominant input from the midbrain roof and (plesiomorphically) from lemniscal pathways, including the optic tract, respectively. Where present, the collothalamic, midbrain-sensory relay nuclei are homologous to each other in all vertebrate radiations as discrete nuclei. Within the lemnothalamus, the dorsal lateral geniculate nucleus of mammals and the dorsal lateral optic nucleus of non-synapsid amniotes (diapsid reptiles, birds and turtles) are homologous as discrete nuclei; most or all of the ventral nuclear group of mammals is homologous as a field to the lemniscal somatosensory relay and motor feedback nuclei of non-synapsid amniotes; the anterior, intralaminar and medial nuclear groups of mammals are collectively homologous as a field to both the dorsomedial and dorsolateral (including perirotundal) nuclei of non-synapsid amniotes; the anterior, intralaminar, medial and ventral nuclear groups and the dorsal lateral geniculate nucleus of mammals are collectively homologous as a field to the nucleus anterior of anamniotes, as are their homologues in non-synapsid amniotes. In the captorhinomorph ancestors of extant land vertebrates, both divisions of the dorsal thalamus were elaborated to some extent due to an increase in proliferation and lateral migration of neurons during development.(ABSTRACT TRUNCATED AT 400 WORDS)
20170312 - Computer Simulation of Developmental ...

EPA Pesticide Factsheets

Rationale: Recent progress in systems toxicology and synthetic biology have paved the way to new thinking about in vitro/in silico modeling of developmental processes and toxicities, both for embryological and reproductive impacts. Novel in vitro platforms such as 3D organotypic culture models, engineered microscale tissues and complex microphysiological systems (MPS), together with computational models and computer simulation of tissue dynamics, lend themselves to a integrated testing strategies for predictive toxicology. As these emergent methodologies continue to evolve, they must be integrally tied to maternal/fetal physiology and toxicity of the developing individual across early lifestage transitions, from fertilization to birth, through puberty and beyond. Scope: This symposium will focus on how the novel technology platforms can help now and in the future, with in vitro/in silico modeling of complex biological systems for developmental and reproductive toxicity issues, and translating systems models into integrative testing strategies. The symposium is based on three main organizing principles: (1) that novel in vitro platforms with human cells configured in nascent tissue architectures with a native microphysiological environments yield mechanistic understanding of developmental and reproductive impacts of drug/chemical exposures; (2) that novel in silico platforms with high-throughput screening (HTS) data, biologically-inspired computational models of
Computer Simulation of Developmental Processes and ...

EPA Pesticide Factsheets

Rationale: Recent progress in systems toxicology and synthetic biology have paved the way to new thinking about in vitro/in silico modeling of developmental processes and toxicities, both for embryological and reproductive impacts. Novel in vitro platforms such as 3D organotypic culture models, engineered microscale tissues and complex microphysiological systems (MPS), together with computational models and computer simulation of tissue dynamics, lend themselves to a integrated testing strategies for predictive toxicology. As these emergent methodologies continue to evolve, they must be integrally tied to maternal/fetal physiology and toxicity of the developing individual across early lifestage transitions, from fertilization to birth, through puberty and beyond. Scope: This symposium will focus on how the novel technology platforms can help now and in the future, with in vitro/in silico modeling of complex biological systems for developmental and reproductive toxicity issues, and translating systems models into integrative testing strategies. The symposium is based on three main organizing principles: (1) that novel in vitro platforms with human cells configured in nascent tissue architectures with a native microphysiological environments yield mechanistic understanding of developmental and reproductive impacts of drug/chemical exposures; (2) that novel in silico platforms with high-throughput screening (HTS) data, biologically-inspired computational models of
Ethical and legal controversies in cloning for biomedical research--a South African perspective.

PubMed

Dhai, A; Moodley, J; McQuoid-Mason, D J; Rodeck, C

2004-11-01

Therapeutic embryonic stem cell research raises a number of ethical and legal issues. The promised benefits are new and important knowledge of human embryological development, gene action, and the production of transplantable tissue and organs that could be effective in reversing or curing currently irreversible disease processes. However, this research involves the deliberate production, use, and ultimate destruction of cloned embryos, hence re-awakening the debate on the moral status of the embryo. Other moral anxieties include the possibility that women (as donors of ova) would be exploited, that this research would land on the slippery slope of reproductive cloning, and that promises made too early could lead to false hope among sick patients. It also raises the question of intellectual and actual property rights in human cell lines and the techniques by which they are produced. Review of legal systems internationally reveals that there is no global consensus on therapeutic embryonic stem cell research. Legal considerations are very much influenced by ethical deliberations on the moral status of the embryo. The South African parliament is promulgating legislation permitting therapeutic cloning, thereby demonstrating a commitment by the state to act in the best interests of patients and of regenerative medicine.
Morphometric discrimination of early life stage Lampetra tridentata and L richardsoni (Petromyzonidae) from the Columbia river basin

USGS Publications Warehouse

Meeuwig, M.H.; Bayer, J.M.; Reiche, R.A.

2006-01-01

The effectiveness of morphometric and meristic characteristics for taxonomic discrimination of Lampetra tridentata and L. richardsoni (Petromyzonidae) during embryological, prolarval, and early larval stages (i.e., age class 1) were examined. Mean chorion diameter increased with time from fertilization to hatch and was significantly greater for L. tridentata than for L. richardsoni at 1, 8, and 15 days postfertilization. Lampetra tridentata larvae had significantly more trunk myomeres than L. richardsoni; however, trunk myomere numbers were highly variable within species and deviated from previously published data. Multivariate examinations of prolarval and larval L. tridentata (7.2-11.0 mm; standard length) and L. richardsoni (6.6-10.8 mm) were conducted based on standard length and truss element lengths established from eight homologous landmarks. Principal components analysis indicated allometric relationships among the morphometric characteristics examined. Changes in body shape were indicated by groupings of morphometric characteristics associated with body regions (e.g., oral hood, branchial region, trunk region, and tail region). Discriminant function analysis using morphometric characteristics was successful in classifying a large proportion (>94.7%) of the lampreys sampled.
Method of Electroporation for the Early Chick Embryo

NASA Astrophysics Data System (ADS)

Hatakeyama, Jun; Shimamura, Kenji

Chick embryos have long been one of the favored model systems in the field of embryology and developmental biology. Recent advances in the gene manipulation technologies (Muramatsu et al., 1997; Nakamura et al., 2004) make this model system even more attractive for the developmental biologists (see review by Stern, 2005). Thanks to its two dimensional geometry, easiness in accessibility and observation, and well-established fate maps (e.g. Couly and Le Douarin, 1988; Garcia-Martinez et al., 1993; Hatada and Stern, 1994; Psychoyos and Stern, 1996; Sawada and Aoyama, 1999; Cobos et al., 2001; Lopez-Sanchez et al., 2001; Redkar et al., 2001; Fernandez-Garre et al., 2002; Kimura et al., 2006; Matsushita et al., 2008), it has great advantages especially for studies at the early embryonic stages, such as the processes of gastrulation, neural induction, left-right patterning, etc. For such purposes, a whole embryo culture system, originally invented by Dennis A. T. New (New, 1955), and its derivatives (Flamme, 1987; Sundin and Eichele, 1992; Stern, 1993; Chapman et al., 2001) have been widely used.
The European embryonic stem-cell debate and the difficulties of embryological Kantianism.

PubMed

Mauron, Alexandre; Baertschi, Bernard

2004-10-01

As elsewhere, the ethical debate on embryonic stem cell research in Central Europe, especially Germany and Switzerland, involves controversy over the status of the human embryo. There is a distinctive Kantian flavor to the standard arguments however, and we show how they often embody a set of misunderstandings and argumentative shortcuts we term"embryological Kantianism."We also undertake a broader analysis of three arguments typically presented in this debate, especially in official position papers, namely the identity, continuity, and potentiality arguments. It turns out that these arguments do not support the strong, quasi-personal status accorded to the embryos in these official opinions.
Congenital cystic neck masses: embryology and imaging appearances, with clinicopathological correlation.

PubMed

Gaddikeri, Santhosh; Vattoth, Surjith; Gaddikeri, Ramya S; Stuart, Royal; Harrison, Keith; Young, Daniel; Bhargava, Puneet

2014-01-01

Congenital cystic masses of the neck are uncommon and can present in any age group. Diagnosis of these lesions can be sometimes challenging. Many of these have characteristic locations and imaging findings. The most common of all congenital cystic neck masses is the thyroglossal duct cyst. The other congenital cystic neck masses are branchial cleft cyst, cystic hygroma (lymphangioma), cervical thymic and bronchogenic cysts, and the floor of the mouth lesions including dermoid and epidermoid cysts. In this review, we illustrate the common congenital cystic neck masses including embryology, clinical findings, imaging features, and histopathological findings. Copyright © 2014 Elsevier, Inc. All rights reserved.
Graphic and movie illustrations of human prenatal development and their application to embryological education based on the human embryo specimens in the Kyoto collection.

PubMed

Yamada, Shigehito; Uwabe, Chigako; Nakatsu-Komatsu, Tomoko; Minekura, Yutaka; Iwakura, Masaji; Motoki, Tamaki; Nishimiya, Kazuhiko; Iiyama, Masaaki; Kakusho, Koh; Minoh, Michihiko; Mizuta, Shinobu; Matsuda, Tetsuya; Matsuda, Yoshimasa; Haishi, Tomoyuki; Kose, Katsumi; Fujii, Shingo; Shiota, Kohei

2006-02-01

Morphogenesis in the developing embryo takes place in three dimensions, and in addition, the dimension of time is another important factor in development. Therefore, the presentation of sequential morphological changes occurring in the embryo (4D visualization) is essential for understanding the complex morphogenetic events and the underlying mechanisms. Until recently, 3D visualization of embryonic structures was possible only by reconstruction from serial histological sections, which was tedious and time-consuming. During the past two decades, 3D imaging techniques have made significant advances thanks to the progress in imaging and computer technologies, computer graphics, and other related techniques. Such novel tools have enabled precise visualization of the 3D topology of embryonic structures and to demonstrate spatiotemporal 4D sequences of organogenesis. Here, we describe a project in which staged human embryos are imaged by the magnetic resonance (MR) microscope, and 3D images of embryos and their organs at each developmental stage were reconstructed based on the MR data, with the aid of computer graphics techniques. On the basis of the 3D models of staged human embryos, we constructed a data set of 3D images of human embryos and made movies to illustrate the sequential process of human morphogenesis. Furthermore, a computer-based self-learning program of human embryology is being developed for educational purposes, using the photographs, histological sections, MR images, and 3D models of staged human embryos. Copyright 2005 Wiley-Liss, Inc.
COX-1 Suppression and Follicle Depletion in the Etiology of Menopause-Associated Ovarian Cancer

DTIC Science & Technology

2008-10-01

form (8), and cause growth inhibition and apoptosis in ovarian cancer cell lines (9). However, the link between morphological inhibition and...of the c-kit receptor. Genes Dev 1990;4:390-400. 2. Mintz B. Embryological development of primordial germ-cells in the mouse: influence of a new...708–14. 12 Rodriguez GC, Walmer DK, Cline M, et al. Effect of progestin on the ovarian epithelium of macaques: cancer prevention through apoptosis
Embryology in the era of proteomics.

PubMed

Katz-Jaffe, Mandy G; McReynolds, Susanna

2013-03-15

Proteomic technologies have begun providing evidence that viable embryos possess unique protein profiles. Some of these potential protein biomarkers have been identified as extracellular and could be used in the development of a noninvasive quantitative method for embryo assessment. The field of assisted reproductive technologies would benefit from defining the human embryonic proteome and secretome, thereby expanding our current knowledge of embryonic cellular processes. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Penile embryology and anatomy.

PubMed

Yiee, Jenny H; Baskin, Laurence S

2010-06-29

Knowledge of penile embryology and anatomy is essential to any pediatric urologist in order to fully understand and treat congenital anomalies. Sex differentiation of the external genitalia occurs between the 7th and 17th weeks of gestation. The Y chromosome initiates male differentiation through the SRY gene, which triggers testicular development. Under the influence of androgens produced by the testes, external genitalia then develop into the penis and scrotum. Dorsal nerves supply penile skin sensation and lie within Buck's fascia. These nerves are notably absent at the 12 o'clock position. Perineal nerves supply skin sensation to the ventral shaft skin and frenulum. Cavernosal nerves lie within the corpora cavernosa and are responsible for sexual function. Paired cavernosal, dorsal, and bulbourethral arteries have extensive anastomotic connections. During erection, the cavernosal artery causes engorgement of the cavernosa, while the deep dorsal artery leads to glans enlargement. The majority of venous drainage occurs through a single, deep dorsal vein into which multiple emissary veins from the corpora and circumflex veins from the spongiosum drain. The corpora cavernosa and spongiosum are all made of spongy erectile tissue. Buck's fascia circumferentially envelops all three structures, splitting into two leaves ventrally at the spongiosum. The male urethra is composed of six parts: bladder neck, prostatic, membranous, bulbous, penile, and fossa navicularis. The urethra receives its blood supply from both proximal and distal directions.
The development of a core syllabus for the teaching of oral anatomy, histology, and embryology to dental students via an international 'Delphi Panel'.

PubMed

Moxham, Bernard John; McHanwell, Stephen; Berkovitz, Barry

2018-03-01

The formulation of core syllabuses for the biomedical sciences within medical and dental courses is partially driven by the need to cope with decreased time allocations for these subjects as a result of major curricular changes taking place worldwide. There is also a requirement to deal with the request for increased clinical relevance. In response to such demands, the International Federation of Associations of Anatomists (IFAA) is devising core syllabuses for the anatomical sciences relating to the education and training of both scientific and clinical professions. The process initially involves using Delphi Panels consisting of a team of anatomists, scientists, and clinicians who evaluate syllabus content in detail and accord each element/topic 'essential,' 'important,' 'acceptable,' or 'not required' status. Their conjectures, published on the IFAA website, provide merely a framework to enable other stakeholders to comment. The approach is international in scope, is conceptually 'democratic,' and is developmentally fluid in being readily available for amendment. The aim is to set internationally recognized standards and thus to provide guidelines concerning anatomical knowledge when engaged in course development. This article presents the deliberations of an IFAA Delphi Panel into a core syllabus for oral anatomy, histology, and embryology within the dental curriculum. Clin. Anat. 31:231-249, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
The diversification of developmental biology.

PubMed

Crowe, Nathan; Dietrich, Michael R; Alomepe, Beverly S; Antrim, Amelia F; ByrneSim, Bay Lauris; He, Yi

2015-10-01

In the 1960s, "developmental biology" became the dominant term to describe some of the research that had previously been included under the rubrics of embryology, growth, morphology, and physiology. As scientific societies formed under this new label, a new discipline took shape. Historians, however, have a number of different perspectives on what changes led to this new field of developmental biology and how the field itself was constituted during this period. Using the General Embryological Information Service, a global index of post-World War II development-related research, we have documented and visualized significant changes in the kinds of research that occurred as this new field formed. In particular, our analysis supports the claim that the transition toward developmental biology was marked by a growth in new topics and forms of research. Although many historians privilege the role of molecular biology and/or the molecularization of biology in general during this formative period, we have found that the influence of molecular biology is not sufficient to account for the wide range of new research that constituted developmental biology at the time. Overall, our work creates a robust characterization of the changes that occurred with regard to research on growth and development in the decades following World War II and provides a context for future work on the specific drivers of those changes. Copyright © 2015 Elsevier Ltd. All rights reserved.
Penile Embryology and Anatomy

PubMed Central

Yiee, Jenny H.; Baskin, Laurence S.

2010-01-01

Knowledge of penile embryology and anatomy is essential to any pediatric urologist in order to fully understand and treat congenital anomalies. Sex differentiation of the external genitalia occurs between the 7and 17 weeks of gestation. The Y chromosome initiates male differentiation through the SRY gene, which triggers testicular development. Under the influence of androgens produced by the testes, external genitalia then develop into the penis and scrotum. Dorsal nerves supply penile skin sensation and lie within Buck's fascia. These nerves are notably absent at the 12 o'clock position. Perineal nerves supply skin sensation to the ventral shaft skin and frenulum. Cavernosal nerves lie within the corpora cavernosa and are responsible for sexual function. Paired cavernosal, dorsal, and bulbourethral arteries have extensive anastomotic connections. During erection, the cavernosal artery causes engorgement of the cavernosa, while the deep dorsal artery leads to glans enlargement. The majority of venous drainage occurs through a single, deep dorsal vein into which multiple emissary veins from the corpora and circumflex veins from the spongiosum drain. The corpora cavernosa and spongiosum are all made of spongy erectile tissue. Buck's fascia circumferentially envelops all three structures, splitting into two leaves ventrally at the spongiosum. The male urethra is composed of six parts: bladder neck, prostatic, membranous, bulbous, penile, and fossa navicularis. The urethra receives its blood supply from both proximal and distal directions. PMID:20602076
Anomalous Origin of the Right Vertebral Artery: Incidence and Significance.

PubMed

Maiti, Tanmoy Kumar; Konar, Subhas Kanti; Bir, Shyamal; Nanda, Anil; Cuellar, Hugo

2016-05-01

Detailed knowledge about anatomic variations of the aortic arch and its multiple branches is extremely important to endovascular and diagnostic radiologists. It is often hypothesized that anomalous origin and distribution of large aortic vessels may alter the cerebral hemodynamics and potentially lead to a vascular pathology. In this article, we describe a case of anomalous origin of the right vertebral artery, which was detected during an intervention. We further reviewed the available literature of anomalous origin of the right vertebral artery. The probable embryologic development and clinical significance are discussed. The incidence of anomalous origin of a vertebral artery seems to be underestimated in recent literature. A careful review of the literature shows more than 100 such cases. The right vertebral artery can arise from the aortic arch or one of its branches. Dual origin of the vertebral artery is not uncommon. The embryologic developmental hypotheses are contradictory and complex. Anomalous origin of the right vertebral artery may not be the sole reason behind a disease process. However, it can certainly lead to a misdiagnosis during diagnostic vascular studies. Detailed information is essential for any surgery or endovascular intervention in this location. Copyright © 2015 Elsevier Inc. All rights reserved.
The hooked element in the pes of turtles (Testudines): a global approach to exploring primary and secondary homology

PubMed Central

Joyce, Walter G; Werneburg, Ingmar; Lyson, Tyler R

2013-01-01

The hooked element in the pes of turtles was historically identified by most palaeontologists and embryologists as a modified fifth metatarsal, and often used as evidence to unite turtles with other reptiles with a hooked element. Some recent embryological studies, however, revealed that this element might represent an enlarged fifth distal tarsal. We herein provide extensive new myological and developmental observations on the hooked element of turtles, and re-evaluate its primary and secondary homology using all available lines of evidence. Digital count and timing of development are uninformative. However, extensive myological, embryological and topological data are consistent with the hypothesis that the hooked element of turtles represents a fusion of the fifth distal tarsal with the fifth metatarsal, but that the fifth distal tarsal dominates the hooked element in pleurodiran turtles, whereas the fifth metatarsal dominates the hooked element of cryptodiran turtles. The term ‘ansulate bone’ is proposed to refer to hooked elements that result from the fusion of these two bones. The available phylogenetic and fossil data are currently insufficient to clarify the secondary homology of hooked elements within Reptilia. PMID:24102560
Reproductive medicine involving genome editing: clinical uncertainties and embryological needs.

PubMed

Ishii, Tetsuya

2017-01-01

Genome editing based on site-directed nucleases facilitated efficient and versatile genetic modifications in human cells. However, recent reports, demonstrating CRISPR/Cas9-mediated genome editing in human embryos have raised profound concerns worldwide. This commentary explores the clinical justification and feasibility of reproductive medicine using germline genome editing. Despite the perceived utility of reproductive medicine for treating intractable infertility, it is difficult to justify germline genome editing from the perspective of the prospective child. As suggested by the UK legalization regarding mitochondrial donation, the prevention of genetic disease in offspring by genome editing might be acceptable in limited cases of serious or life-threatening conditions, where no alternative medicine is available. Nonetheless, the mosaicism underlying human embryos as well as the off-target effect by artificial nucleases will likely hamper preimplantation genetic diagnosis prior to embryo transfer. Such considerations suggest that this type of reproductive medicine should not be developed toward a clinical application. However, the clinical uncertainties underscore the need for embryology that can address fundamental questions regarding germline aneuploidy and mosaicism using genome editing. Copyright © 2016 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
Review: the role of neural crest cells in the endocrine system.

PubMed

Adams, Meghan Sara; Bronner-Fraser, Marianne

2009-01-01

The neural crest is a pluripotent population of cells that arises at the junction of the neural tube and the dorsal ectoderm. These highly migratory cells form diverse derivatives including neurons and glia of the sensory, sympathetic, and enteric nervous systems, melanocytes, and the bones, cartilage, and connective tissues of the face. The neural crest has long been associated with the endocrine system, although not always correctly. According to current understanding, neural crest cells give rise to the chromaffin cells of the adrenal medulla, chief cells of the extra-adrenal paraganglia, and thyroid C cells. The endocrine tumors that correspond to these cell types are pheochromocytomas, extra-adrenal paragangliomas, and medullary thyroid carcinomas. Although controversies concerning embryological origin appear to have mostly been resolved, questions persist concerning the pathobiology of each tumor type and its basis in neural crest embryology. Here we present a brief history of the work on neural crest development, both in general and in application to the endocrine system. In particular, we present findings related to the plasticity and pluripotency of neural crest cells as well as a discussion of several different neural crest tumors in the endocrine system.
Flight feather development: its early specialization during embryogenesis.

PubMed

Kondo, Mao; Sekine, Tomoe; Miyakoshi, Taku; Kitajima, Keiichi; Egawa, Shiro; Seki, Ryohei; Abe, Gembu; Tamura, Koji

2018-01-01

Flight feathers, a type of feather that is unique to extant/extinct birds and some non-avian dinosaurs, are the most evolutionally advanced type of feather. In general, feather types are formed in the second or later generation of feathers at the first and following molting, and the first molting begins at around two weeks post hatching in chicken. However, it has been stated in some previous reports that the first molting from the natal down feathers to the flight feathers is much earlier than that for other feather types, suggesting that flight feather formation starts as an embryonic event. The aim of this study was to determine the inception of flight feather morphogenesis and to identify embryological processes specific to flight feathers in contrast to those of down feathers. We found that the second generation of feather that shows a flight feather-type arrangement has already started developing by chick embryonic day 18, deep in the skin of the flight feather-forming region. This was confirmed by shh gene expression that shows barb pattern, and the expression pattern revealed that the second generation of feather development in the flight feather-forming region seems to start by embryonic day 14. The first stage at which we detected a specific morphology of the feather bud in the flight feather-forming region was embryonic day 11, when internal invagination of the feather bud starts, while the external morphology of the feather bud is radial down-type. The morphogenesis for the flight feather, the most advanced type of feather, has been drastically modified from the beginning of feather morphogenesis, suggesting that early modification of the embryonic morphogenetic process may have played a crucial role in the morphological evolution of this key innovation. Co-optation of molecular cues for axial morphogenesis in limb skeletal development may be able to modify morphogenesis of the feather bud, giving rise to flight feather-specific morphogenesis of traits.

A genomic regulatory network for development

NASA Technical Reports Server (NTRS)

Davidson, Eric H.; Rast, Jonathan P.; Oliveri, Paola; Ransick, Andrew; Calestani, Cristina; Yuh, Chiou-Hwa; Minokawa, Takuya; Amore, Gabriele; Hinman, Veronica; Arenas-Mena, Cesar;

2002-01-01

Development of the body plan is controlled by large networks of regulatory genes. A gene regulatory network that controls the specification of endoderm and mesoderm in the sea urchin embryo is summarized here. The network was derived from large-scale perturbation analyses, in combination with computational methodologies, genomic data, cis-regulatory analysis, and molecular embryology. The network contains over 40 genes at present, and each node can be directly verified at the DNA sequence level by cis-regulatory analysis. Its architecture reveals specific and general aspects of development, such as how given cells generate their ordained fates in the embryo and why the process moves inexorably forward in developmental time.

Divided café-au-lait macule of the mouth.

PubMed

Sergay, Amanda; Silverberg, Nanette B

2007-05-01

We describe a 4-year-old, otherwise healthy boy with a congenital history of a perioral and labial segmental café-au-lait macule, who was noted to have unilateral localized gingival hyperpigmentation that aligned with the café-au-lait macule. This case is highly illustrative of the embryologic timing of the genetic event locally, which leads to café-au-lait type hyperpigmentation. Because the facial features and the ectoderm overlying the facial muscles develop around the third to fourth week of gestation, the distribution of this café-au-lait macule suggests development at the same time.
Problems in radiation embryology. Sixteenth year progress report, July 1, 1972-June 30, 1973

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1973-01-01

Progress is reported in the following areas: (1) the effect of embryonic irradiation on adult life expectancy, adult pathology and leukemia induction; (2) the effect of embryonic irradiation on biochemical and physiological processes in the adult organism; (3) attempts specifically to irradiate the developing rat yolk sac; (4) the effect of x-irradiating the rat embryo on the first day of gestation; and (5) determination of the threshold exposure for malformation induction in irradiated embryos. (ACR)
Confocal imaging of whole vertebrate embryos reveals novel insights into molecular and cellular mechanisms of organ development

NASA Astrophysics Data System (ADS)

Hadel, Diana M.; Keller, Bradley B.; Sandell, Lisa L.

2014-03-01

Confocal microscopy has been an invaluable tool for studying cellular or sub-cellular biological processes. The study of vertebrate embryology is based largely on examination of whole embryos and organs. The application of confocal microscopy to immunostained whole mount embryos, combined with three dimensional (3D) image reconstruction technologies, opens new avenues for synthesizing molecular, cellular and anatomical analysis of vertebrate development. Optical cropping of the region of interest enables visualization of structures that are morphologically complex or obscured, and solid surface rendering of fluorescent signal facilitates understanding of 3D structures. We have applied these technologies to whole mount immunostained mouse embryos to visualize developmental morphogenesis of the mammalian inner ear and heart. Using molecular markers of neuron development and transgenic reporters of neural crest cell lineage we have examined development of inner ear neurons that originate from the otic vesicle, along with the supporting glial cells that derive from the neural crest. The image analysis reveals a previously unrecognized coordinated spatial organization between migratory neural crest cells and neurons of the cochleovestibular nerve. The images also enable visualization of early cochlear spiral nerve morphogenesis relative to the developing cochlea, demonstrating a heretofore unknown association of neural crest cells with extending peripheral neurite projections. We performed similar analysis of embryonic hearts in mouse and chick, documenting the distribution of adhesion molecules during septation of the outflow tract and remodeling of aortic arches. Surface rendering of lumen space defines the morphology in a manner similar to resin injection casting and micro-CT.
Embryonic staging and external features of development of the Chimaeroid fish, Callorhinchus milii (Holocephali, Callorhinchidae).

PubMed

Didier, Dominique A; LeClair, Elizabeth E; Vanbuskirk, Dana R

1998-04-01

The development of Callorhinchus milii, a primitive chondrichthyan fish (Subclass Holocephali) is described in detail based on a complete series of embryos from stage 17 to hatching. The external features of these specimens, in comparison with other chondrichthyan embryos, are used to establish the first staging table for any chimaeroid species. Each stage of C. milii is defined by a suite of morphological characters in addition to total length, including the number of somites, extent of external pigmentation, eye size and shape, head flexure, heart morphology, and size and shape of paired and unpaired fins. Particular attention is given to features of the gill arches and associated structures, including external gill filaments and the opercular flap. Embryos of this species also possess a transient rostral bulb, a feature unique to chimaeroids. Embryological development of Callorhinchus milii is similar to that previously described for sharks and batoids (Subclass Elasmobranchii), including the spiny dogfish, Squalus acanthias, the Japanese bullshark, Heterodontus japonicus, the lesser spotted dogfish, Scyliorhinus canicula, the frill shark, Chlamydoselachus anguineus, the guitarfish, Rhinobatus halavi, and the skate, Raja brachyura. Callorhinchus milii is also similar in overall development to another holocephalan, Hydrolagus colliei. A review of previous staging schemes confirms that early morphological development in all three major chondrichthyan lineages (sharks, batoids, and chimaeras) can be correlated using a common set of stages. A uniform staging system is provided that should prove useful in continuing ontogenetic and phylogenetic studies of this entire clade of fishes. J. Morphol. 236:25-47, 1998. © 1998 Wiley-Liss, Inc. Copyright © 1998 Wiley-Liss, Inc.
Developmental and evolutionary significance of the mandibular arch and prechordal/premandibular cranium in vertebrates: revising the heterotopy scenario of gnathostome jaw evolution

PubMed Central

Kuratani, Shigeru; Adachi, Noritaka; Wada, Naoyuki; Oisi, Yasuhiro; Sugahara, Fumiaki

2013-01-01

The cephalic neural crest produces streams of migrating cells that populate pharyngeal arches and a more rostral, premandibular domain, to give rise to an extensive ectomesenchyme in the embryonic vertebrate head. The crest cells forming the trigeminal stream are the major source of the craniofacial skeleton; however, there is no clear distinction between the mandibular arch and the premandibular domain in this ectomesenchyme. The question regarding the evolution of the gnathostome jaw is, in part, a question about the differentiation of the mandibular arch, the rostralmost component of the pharynx, and in part a question about the developmental fate of the premandibular domain. We address the developmental definition of the mandibular arch in connection with the developmental origin of the trabeculae, paired cartilaginous elements generally believed to develop in the premandibular domain, and also of enigmatic cartilaginous elements called polar cartilages. Based on comparative embryology, we propose that the mandibular arch ectomesenchyme in gnathostomes can be defined as a Dlx1-positive domain, and that the polar cartilages, which develop from the Dlx1-negative premandibular ectomesenchyme, would represent merely posterior parts of the trabeculae. We also show, in the lamprey embryo, early migration of mandibular arch mesenchyme into the premandibular domain, and propose an updated version of the heterotopy theory on the origin of the jaw. PMID:22500853
Embryonic cardiac morphometry in Carnegie stages 15-23, from the Complutense University of Madrid Institute of Embryology Human Embryo Collection.

PubMed

Arráez-Aybar, L A; Turrero-Nogués, A; Marantos-Gamarra, D G

2008-01-01

We performed a morphometric study of cardiac development on human embryos to complement the scarce data on human embryonic cardiac morphometry and to attempt to establish, from these, algorithms describing cardiac growth during the second month of gestation. Thirty human embryos from Carnegie stages 15-23 were included in the study. Shrinkage and compression effects from fixation and inclusion in paraffin were considered in our calculations. Growth of the cardiac (whole heart) volume and volume of ventricular myocardium through the Carnegie stages were analysed by ANOVA. Linear correlation was used to describe the relationship between the ventricular myocardium and cardiac volumes. Comparisons of models were carried out through the R2 statistic. The relationship volume of ventricular myocardium versus cardiac volume is expressed by the equation: cardiac volume = 0.6266 + 2.4778 volume of ventricular myocardium. The relationship cardiac volume versus crown-rump length is expressed by the equation: cardiac volume = 1.3 e(0.126 CR length), where e is the base of natural logarithms. At a clinical level, these results can contribute towards the establishment of a normogram for cardiac development, useful for the design of strategies for early diagnosis of congenital heart disease. They can also help in the study of embryogenesis, for example in the discussion of ventricular trabeculation. Copyright 2007 S. Karger AG, Basel.
Three-dimensional imaging of the brain cavities in human embryos.

PubMed

Blaas, H G; Eik-Nes, S H; Kiserud, T; Berg, S; Angelsen, B; Olstad, B

1995-04-01

A system for high-resolution three-dimensional imaging of small structures has been developed, based on the Vingmed CFM-800 annular array sector scanner with a 7.5-MHz transducer attached to a PC-based TomTec Echo-Scan unit. A stepper motor rotates the transducer 180 degrees and the complete three-dimensional scan consists of 132 two-dimensional images, video-grabbed and scan-converted into a regular volumetric data set by the TomTec unit. Three normal pregnancies with embryos of gestational age 7, 9 and 10 weeks received a transvaginal examination with special attention to the embryonic/fetal brain. In all three cases, it was possible to obtain high-resolution images of the brain cavities. At 7 weeks, both hemispheres and their connection to the third ventricle were delineated. The isthmus rhombencephali could be visualized. At 9 weeks, the continuous development of the brain cavities could be followed and at 11 weeks the dominating size of the hemispheres could be depicted. It is concluded that present ultrasound technology has reached a stage where structures of only a few millimeters can be imaged in vivo in three-dimensions with a quality that resembles the plaster figures used in embryonic laboratories. The method can become an important tool in future embryological research and also in the detection of early developmental disorders of the embryo.
Evolution of the vertebrate jaw: comparative embryology and molecular developmental biology reveal the factors behind evolutionary novelty

PubMed Central

Kuratani, Shigeru

2004-01-01

It is generally believed that the jaw arose through the simple transformation of an ancestral rostral gill arch. The gnathostome jaw differentiates from Hox-free crest cells in the mandibular arch, and this is also apparent in the lamprey. The basic Hox code, including the Hox-free default state in the mandibular arch, may have been present in the common ancestor, and jaw patterning appears to have been secondarily constructed in the gnathostomes. The distribution of the cephalic neural crest cells is similar in the early pharyngula of gnathostomes and lampreys, but different cell subsets form the oral apparatus in each group through epithelial–mesenchymal interactions: and this heterotopy is likely to have been an important evolutionary change that permitted jaw differentiation. This theory implies that the premandibular crest cells differentiate into the upper lip, or the dorsal subdivision of the oral apparatus in the lamprey, whereas the equivalent cell population forms the trabecula of the skull base in gnathostomes. Because the gnathostome oral apparatus is derived exclusively from the mandibular arch, the concepts ‘oral’ and ‘mandibular’ must be dissociated. The ‘lamprey trabecula’ develops from mandibular mesoderm, and is not homologous with the gnathostome trabecula, which develops from premandibular crest cells. Thus the jaw evolved as an evolutionary novelty through tissue rearrangements and topographical changes in tissue interactions. PMID:15575882
Esophageal atresia

MedlinePlus

Madanick R, Orlando RC. Anatomy, histology, embryology, and developmental anomalies of the esophagus. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver ...
The developmental programme for genesis of the entire kidney is recapitulated in Wilms tumour.

PubMed

Fukuzawa, Ryuji; Anaka, Matthew R; Morison, Ian M; Reeve, Anthony E

2017-01-01

Wilms tumour (WT) is an embryonal tumour that recapitulates kidney development. The normal kidney is formed from two distinct embryological origins: the metanephric mesenchyme (MM) and the ureteric bud (UB). It is generally accepted that WT arises from precursor cells in the MM; however whether UB-equivalent structures participate in tumorigenesis is uncertain. To address the question of the involvement of UB, we assessed 55 Wilms tumours for the molecular features of MM and UB using gene expression profiling, immunohistochemsitry and immunofluorescence. Expression profiling primarily based on the Genitourinary Molecular Anatomy Project data identified molecular signatures of the UB and collecting duct as well as those of the proximal and distal tubules in the triphasic histology group. We performed immunolabeling for fetal kidneys and WTs. We focused on a central epithelial blastema pattern which is the characteristic of triphasic histology characterized by UB-like epithelial structures surrounded by MM and MM-derived epithelial structures, evoking the induction/aggregation phase of the developing kidney. The UB-like epithelial structures and surrounding MM and epithelial structures resembling early glomerular epithelium, proximal and distal tubules showed similar expression patterns to those of the developing kidney. These observations indicate WTs can arise from a precursor cell capable of generating the entire kidney, such as the cells of the intermediate mesoderm from which both the MM and UB are derived. Moreover, this provides an explanation for the variable histological features of mesenchymal to epithelial differentiation seen in WT.
A 3D reconstruction of pancreas development in the human embryos during embryonic period (Carnegie stages 15-23).

PubMed

Radi, M; Gaubert, J; Cristol-Gaubert, R; Baecker, V; Travo, P; Prudhomme, M; Godlewski, G; Prat-Pradal, D

2010-01-01

The goal in this paper was to rebuild a three dimensional (3D) reconstruction of the dorsal and ventral pancreatic buds, in the human embryos, at Carnegie stages 15-23. The early development of the pancreas is studied by tissue observation and reconstruction by a computer-assisted method, using a light micrograph images from consecutive serial sagittal sections (diameter 7 microm) of ten human embryos ranging from Carnegie stages 15-23, CRL 7-27 mm, fixed, dehydrated and embedded in paraffin, were stained alternately with haematoxylin-eosin or Heindenhain'Azan. The images were digitalized by Canon Camera 350 EOS D. The serial views were aligned automatically by software, manual alignment was performed, the data were analysed following segmentation and threshold. The two buds were clearly identified at stage 15. In stage 16, both pancreatic buds were in final position, and begin to merge in stage 17. From stage 18 to the stage 23, surrounding connective tissue differentiated. In the stage 23, the morphology of the pancreas was definitive. The superior portion of the anterior face of the pancreas's head was arising from the dorsal bud. The rest of the head including the uncinate process emanated from the ventral bud. The 3D computer-assisted reconstruction of the human pancreas visualized the relationships between the two pancreatic buds. This explains the disposition and the modality of the components fusion. This embryologic development permits a better understanding of congenital abnormalities.
The developmental programme for genesis of the entire kidney is recapitulated in Wilms tumour

PubMed Central

Anaka, Matthew R.; Morison, Ian M.; Reeve, Anthony E.

2017-01-01

Wilms tumour (WT) is an embryonal tumour that recapitulates kidney development. The normal kidney is formed from two distinct embryological origins: the metanephric mesenchyme (MM) and the ureteric bud (UB). It is generally accepted that WT arises from precursor cells in the MM; however whether UB-equivalent structures participate in tumorigenesis is uncertain. To address the question of the involvement of UB, we assessed 55 Wilms tumours for the molecular features of MM and UB using gene expression profiling, immunohistochemsitry and immunofluorescence. Expression profiling primarily based on the Genitourinary Molecular Anatomy Project data identified molecular signatures of the UB and collecting duct as well as those of the proximal and distal tubules in the triphasic histology group. We performed immunolabeling for fetal kidneys and WTs. We focused on a central epithelial blastema pattern which is the characteristic of triphasic histology characterized by UB-like epithelial structures surrounded by MM and MM-derived epithelial structures, evoking the induction/aggregation phase of the developing kidney. The UB-like epithelial structures and surrounding MM and epithelial structures resembling early glomerular epithelium, proximal and distal tubules showed similar expression patterns to those of the developing kidney. These observations indicate WTs can arise from a precursor cell capable of generating the entire kidney, such as the cells of the intermediate mesoderm from which both the MM and UB are derived. Moreover, this provides an explanation for the variable histological features of mesenchymal to epithelial differentiation seen in WT. PMID:29040332
The embryogenesis of the tick Rhipicephalus (Boophilus) microplus: the establishment of a new chelicerate model system.

PubMed

Santos, Vitória Tobias; Ribeiro, Lupis; Fraga, Amanda; de Barros, Cíntia Monteiro; Campos, Eldo; Moraes, Jorge; Fontenele, Marcio Ribeiro; Araújo, Helena Marcolla; Feitosa, Natalia Martins; Logullo, Carlos; da Fonseca, Rodrigo Nunes

2013-12-01

Chelicerates, which include spiders, ticks, mites, scorpions, and horseshoe crabs, are members of the phylum Arthropoda. In recent years, several molecular experimental studies of chelicerates have examined the embryology of spiders; however, the embryology of other groups, such as ticks (Acari: Parasitiformes), has been largely neglected. Ticks and mites are believed to constitute a monophyletic group, the Acari. Due to their blood-sucking activities, ticks are also known to be vectors of several diseases. In this study, we analyzed the embryonic development of the cattle tick, Rhipicephalus (Boophilus) microplus (Acari: Ixodidae). First, we developed an embryonic staging system consisting of 14 embryonic stages. Second, histological analysis and antibody staining unexpectedly revealed the presence of a population of tick cells with similar characteristics to the spider cumulus. Cumulus cell populations also exist in other chelicerates; these cells are responsible for the breaking of radial symmetry through bone morphogenetic protein signaling. Third, it was determined that the posterior (opisthosomal) embryonic region of R. microplus is segmented. Finally, we identified the presence of a transient ventral midline furrow and the formation and regression of a fourth leg pair; these features may be regarded as hallmarks of late tick embryogenesis. Importantly, most of the aforementioned features are absent from mite embryos, suggesting that mites and ticks do not constitute a monophyletic group or that mites have lost these features. Taken together, our findings provide fundamental common ground for improving knowledge regarding tick embryonic development, thereby facilitating the establishment of a new chelicerate model system. Copyright © 2013 Wiley Periodicals, Inc.
Adult mouse brain gene expression patterns bear an embryologic imprint

PubMed Central

Zapala, Matthew A.; Hovatta, Iiris; Ellison, Julie A.; Wodicka, Lisa; Del Rio, Jo A.; Tennant, Richard; Tynan, Wendy; Broide, Ron S.; Helton, Rob; Stoveken, Barbara S.; Winrow, Christopher; Lockhart, Daniel J.; Reilly, John F.; Young, Warren G.; Bloom, Floyd E.; Lockhart, David J.; Barlow, Carrolee

2005-01-01

The current model to explain the organization of the mammalian nervous system is based on studies of anatomy, embryology, and evolution. To further investigate the molecular organization of the adult mammalian brain, we have built a gene expression-based brain map. We measured gene expression patterns for 24 neural tissues covering the mouse central nervous system and found, surprisingly, that the adult brain bears a transcriptional “imprint” consistent with both embryological origins and classic evolutionary relationships. Embryonic cellular position along the anterior–posterior axis of the neural tube was shown to be closely associated with, and possibly a determinant of, the gene expression patterns in adult structures. We also observed a significant number of embryonic patterning and homeobox genes with region-specific expression in the adult nervous system. The relationships between global expression patterns for different anatomical regions and the nature of the observed region-specific genes suggest that the adult brain retains a degree of overall gene expression established during embryogenesis that is important for regional specificity and the functional relationships between regions in the adult. The complete collection of extensively annotated gene expression data along with data mining and visualization tools have been made available on a publicly accessible web site (www.barlow-lockhart-brainmapnimhgrant.org). PMID:16002470
Laparoscopic surgery for colon cancer: a review of the fascial composition of the abdominal cavity.

PubMed

Mike, Makio; Kano, Nobuyasu

2015-02-01

Laparoscopic surgery has generally been performed for digestive diseases. Many patients with colon cancer undergo laparoscopic procedures. The outcomes of laparoscopic colectomy and open colectomy are the same in terms of the long-time survival. It is important to dissect the embryological plane to harvest the lymph nodes and to avoid bleeding during colon cancer surgery. To date, descriptions of the anatomy of the fascial composition have mainly involved observations unrelated to fundamental embryological concepts, causing confusion regarding the explanations of the surgical procedures, with various vocabularies used without definitions. We therefore examined the fascia of the abdominal space using a fascia concept based on clinical anatomy and embryology. Mobilization of the bilateral sides of the colon involves dissection between the fusion fascia of Toldt and the deep subperitoneal fascia. It is important to understand that the right fusion fascia of Toldt is divided into the posterior pancreatic fascia of Treitz dorsally and the anterior pancreatic fascia ventrally at the second portion of the duodenum. A comprehensive understanding of fascia composition between the stomach and transverse colon is necessary for dissecting the splenic flexure of the colon. As a result of these considerations of the fascia, more accurate surgical procedures can be performed for the excision of colon cancer.
External quality control for embryology laboratories.

PubMed

Castilla, Jose Antonio; Ruiz de Assín, Rafael; Gonzalvo, Maria Carmen; Clavero, Ana; Ramírez, Juan Pablo; Vergara, Francisco; Martínez, Luis

2010-01-01

Participation in external quality control (EQC) programmes is recommended by various scientific societies. Results from an EQC programme for embryology laboratories are presented. This 5-year programme consisted of the annual delivery of (i) materials to test toxicity and (ii) a DVD/CD-ROM with images of zygotes and embryos on days 2 and 3, on the basis of which the participants were asked to judge the embryo quality and to take a clinical decision. A high degree of agreement was considered achieved when over 75% of the laboratories produced similar classifications. With respect to the materials analysed, the specificity was 68% and the sensitivity was 83%. Concerning embryo classification, the proportion of embryos on which a high degree of agreement was achieved increased during this period from 35% to 55%. No improvement was observed in the degree of agreement on the clinical decision to be taken. Day-3 embryos produced a higher degree of agreement (58%) than did day-2 embryos (32%) (P<0.05). Participation in EQC increased the degree of inter-laboratory agreement on embryo classification, but not the corresponding agreement on clinical decision taking. It is necessary to introduce measures aimed at standardizing decision taking procedures in embryology laboratories. Copyright (c) 2009 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
Desperately seeking donors: the 'saviour sibling' decision in Quintavalle v Human Fertilisation and Embryology Authority (UK).

PubMed

Hocking, Barbara Ann; Guy, Scott

2005-08-01

The recent House of Lords decision in Quintavalle v Human Fertilisation and Embryology Authority has raised difficult and complex issues regarding the extent to which embryo selection and reproductive technology can be used as a means of rectifying genetic disorders and treating critically ill children. This comment outlines the facts of Quintavalle and explores how the House of Lords approached the legal, ethical and policy issues that arose out of the Human Fertilisation and Embryology Authority's (UK) decision to allow reproductive and embryo technology to be used to produce a 'saviour sibling' whose tissue could be used to save the life of a critically ill child. Particular attention will be given to the implications of the decision in Quintavalle for Australian family and medical law and policy. As part of this focus, the comment explores the current Australian legislative and policy framework regarding the use of genetic and reproductive technology as a mechanism through which to assist critically ill siblings. It is argued that the present Australian framework would appear to impose significant limits on the medical uses of genetic technology and, in this context, would seem to reflect many of the principles that were articulated by the House of Lords in Quintavalle.
Pre-modern Islamic medical ethics and Graeco-Islamic-Jewish embryology.

PubMed

Ghaly, Mohammed

2014-02-01

This article examines the, hitherto comparatively unexplored, reception of Greek embryology by medieval Muslim jurists. The article elaborates on the views attributed to Hippocrates (d. ca. 375 BC), which received attention from both Muslim physicians, such as Avicenna (d. 1037), and their Jewish peers living in the Muslim world including Ibn Jumay' (d. ca. 1198) and Moses Maimonides (d. 1204). The religio-ethical implications of these Graeco-Islamic-Jewish embryological views were fathomed out by the two medieval Muslim jurists Shihāb al-Dīn al-Qarāfī (d. 1285) and Ibn al-Qayyim (d. 1350). By putting these medieval religio-ethical discussions into the limelight, the article aims to argue for a two-pronged thesis. Firstly, pre-modern medical ethics did exist in the Islamic tradition and available evidence shows that this field had a multidisciplinary character where the Islamic scriptures and the Graeco-Islamic-Jewish medical legacy were highly intertwined. This information problematizes the postulate claiming that medieval Muslim jurists were hostile to the so-called 'ancient sciences'. Secondly, these medieval religio-ethical discussions remain playing a significant role in shaping the nascent field of contemporary Islamic bioethics. However, examining the exact character and scope of this role still requires further academic ventures. © 2013 John Wiley & Sons Ltd.
Variations of the superficial middle cerebral vein: classification using three-dimensional CT angiography.

PubMed

Suzuki, Y; Matsumoto, K

2000-05-01

Classification of variations of the superficial middle cerebral vein (SMCV) remains ambiguous. We propose a new classification system based on embryologic development for preoperative examination. Three-dimensional CT angiography was used to evaluate 500 SMCVs (in 250 patients). The outflow vessels from the SMCV were classified into seven types on the basis of embryologic development. The 3D CT angiograms in axial stereoscopic and oblique views and multiple intensity projection images were evaluated by the same neurosurgeon on two occasions. Inconsistent interpretations were regarded as equivocal. Three-dimensional CT angiography clearly depicted the SMCV running along the lesser wing or the middle cranial fossa. However, the outflow vessel could not be confirmed as the sphenoparietal, cavernous, or emissary type in 39 (8%) of the sides. SMCVs running in the middle cranial fossa to join the transverse sinus or superior petrosal sinus were accurately identified. SMCVs were present in 456 sides: 62% entered the sphenoparietal sinus or the cavernous sinus and 12% joined the emissary vein. Nine vessels were the superior petrosal type, 10 the basal type, 12 the squamosal type, and 44 the undeveloped type. Three-dimensional CT angiography can depict the vessels and their anatomic relationship to the bone structure, allowing identification of the SMCV variant in individual patients. Preoperative planning for skull base surgery requires such information to reduce the invasiveness of the procedure. With the use of our classification system, 3D CT angiography can provide exact and practical information concerning the SMCV.

The embryological development of primary visual centres in the turtle Emys orbicularis.

PubMed Central

Hergueta, S; Lemire, M; Pieau, C; Ward, R; Repérant, J

1993-01-01

The development of the primary visual centres was studied in a series of embryos of the turtle, Emys orbicularis, incubated at 25 degrees C. The differentiation of both visual and nonvisual diencephalic and mesencephalic structures takes place entirely within the 2nd quarter of the period of incubation; this finding appears to be consistent with previous descriptions of the embryology of 2 other chelonian species, Lepidochelys and Chelydra. Two successive waves of migration, each dividing into internal and external sheaves, are involved in the formation of the structures of the diencephalon and mesencephalon. The primary visual centres, which comprise 2 hypothalamic, 5 thalamic and 5 pretectal zones of retinal projections, together with the 2 superficial layers of the tectum and a single tegmental projection zone, all have their origin in the external sheaf of the 1st wave of migration. The finding that the adult nucleus geniculatus lateralis dorsalis, pars ventralis arises from one of the migrations of the dorsal thalamus is discussed in the context of the debate over the possible homologues of the mammalian geniculostriate visual pathway. Images Fig. 1 (cont.) Fig. 1 Fig. 2 (cont.) Fig. 2 Fig. 3 (cont.) Fig. 3 Fig. 4 (cont.) Fig. 4 Fig. 5 (cont.) Fig. 5 Fig. 6 (cont.) Fig. 6 Fig. 7 Fig. 8 (cont.) Fig. 8 Fig. 9 (cont.) Fig. 9 Fig. 10 (cont.) Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 PMID:8300423
Triple paternal contribution to a normal/complete molar chimeric singleton placenta.

PubMed

Ariel, I; Goldman-Wohl, D; Yagel, S; Gazit, E; Loewenthal, R

2017-05-01

A comprehensive study of unusual cases of placental pathology may provide insight into mechanisms of normal human fertilization and early embryonic development by examining the exception to the rule. A gravida three para two 39-year-old woman was monitored by ultrasound from 16 weeks of gestation for cystic placenta. A female newborn was born at 36 weeks gestation. Pathologic examination of the partially cystic placenta revealed a singleton placenta comprised of 2/3 normal placenta and 1/3 complete hydatidiform mole, largely degenerated. Immunostaining for p57 was negative in stromal cells of the molar villi. Chromogenic in-situ hybridization revealed diploidy in both normal and molar parts. A total of 16 microsatellites were studied by short tandem repeat analysis, 11 of which were informative. The analysis revealed bipaternal molar tissue of dispermic origin. The paternal monospermic contribution to the normal part was different from that in the molar part, thus resulting in tripaternal contribution to the conceptus. A chimera is a single organism composed of two or more different populations of genetically distinct cells that originated from different zygotes (tetragametic) whereas mosaic is a mixture of two cell lines in one organism originating from one zygote. The possible mechanisms leading to the formation of chimeric/mosaic placenta in our case (one of the components being complete hydatidiform mole), including twinning, fusion at an early embryonic stage and diploidization of triploids, are discussed. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Palatogenesis: morphogenetic and molecular mechanisms of secondary palate development

PubMed Central

Bush, Jeffrey O.; Jiang, Rulang

2012-01-01

Mammalian palatogenesis is a highly regulated morphogenetic process during which the embryonic primary and secondary palatal shelves develop as outgrowths from the medial nasal and maxillary prominences, respectively, remodel and fuse to form the intact roof of the oral cavity. The complexity of control of palatogenesis is reflected by the common occurrence of cleft palate in humans. Although the embryology of the palate has long been studied, the past decade has brought substantial new knowledge of the genetic control of secondary palate development. Here, we review major advances in the understanding of the morphogenetic and molecular mechanisms controlling palatal shelf growth, elevation, adhesion and fusion, and palatal bone formation. PMID:22186724
Cats, frogs, and snakes: early concepts of neural tube defects.

PubMed

Obladen, Michael

2011-11-01

Disturbed neurulation fascinated scientists of all times. In Egypt, anencephalic infants were venerated as animal-headed gods. Roman law required them to be killed. The medieval world held the mother responsible, either because of assumed imagination or "miswatching," or because of suspected intercourse with animals or devils. Modern embryology and teratology began with the use of the microscope by Malpighi in 1672. Details of neural tube closure were described by Koelliker in 1861 and by His in 1874. From 1822, genetic disease and familial recurrence due to insufficient nutrition were discerned and lower social class identified as a risk factor. It took a century to define the malnutrition as insufficient folate intake. The mandatory supplementation of folate in staple foods successfully reduced the incidence of neural tube defects in the United States, Australia, Canada, and Chile, but it was not adopted by most European countries.
Unusual association of adrenal pheochromocytoma and para-aortic neurofibroma in pregnancy.

PubMed

Moretti, A; Minuto, M; Berti, P; Bernini, G P; Mannelli, M; Miccoli, P

2006-09-01

The association of pheochromocytoma (PHEO) and pregnancy is uncommon and life threatening for both the fetus and the mother. Early diagnosis and treatment is essential to decrease maternal and fetal mortality and to differentiate the disease from the more common pre-eclampsia. While medical treatment should be started immediately after diagnosis, the timing of surgical treatment is still debated. We describe the case of a 27-yr-old woman in the 18th week of pregnancy who showed a biochemical pattern typical of PHEO and, by imaging studies, 2 tumors with the same characteristics: the first localized on the right adrenal gland, the second at the right renal hilum. The patient underwent surgery because of suspicion of malignant PHEO with local metastasis, while histology revealed a rare association of a solitary PHEO and para-aortic neurofibroma, both tumors embryologically deriving from a common cell precursor.
[Cor triatriatum. Anatomical forms and surgical treatment of 6 consecutive cases].

PubMed

Bloch, G; Heurtematte, Y; Menu, P; Mesnildrey, P; Casasoprana, A; Magnier, S; Tamari, W; Seurat, M C; Aubry, P; Vernant, P

1988-01-01

Six cases of cor triatriatum documented and operated on at Henri-Mondor hospital between 1980 and 1984 are reported. Ages at the time of surgery ranged from 8 months to 57 years. Four of the 6 patients presented with pulmonary hypertension. Anatomic types consisted of 4 diaphragmatic types and 2 more complex malformations. Associated lesions were present in all but one patients. They consisted mostly of interatrial defects (depending on their position with regard to the intra-atrial membrane, they play a determinant role in the symptomatology) and of a left superior vena cava (which might play a role in the embryogenesis of the malformation). Except for one early postoperative death, results of surgery were excellent for all patients, with a mean follow-up of 5 years. This series, compared with the literature, allows precising the embryologic and anatomic aspects of the malformation and the surgical techniques in complex types.
Inner ear abnormalities in patients with Goldenhar syndrome.

PubMed

Bisdas, Sotirios; Lenarz, Minoo; Lenarz, Thomas; Becker, Hartmut

2005-05-01

The objective of this study is to investigate the inner ear malformations in patients with Goldenhar syndrome and to hypothesize the potential embryopathogenesis of these malformations. Retrospective case review. Tertiary referral center. Fourteen patients with Goldenhar syndrome. Each patient underwent hearing tests and high-resolution computed tomography (CT) of the temporal bone. In six patients, magnetic resonance imaging of the temporal bone also was performed. Among the 14 patients with Goldenhar syndrome, 13 had outer and middle ear anomalies and 5 (36%) had inner ear malformations, including one case of common cavity. Our observations regarding inner ear anomalies in Goldenhar syndrome correlate with the reported cases in the literature and may help to hypothesize the embryological origin of these malformations, which can caused by an early developmental arrest in the fourth gestational week. Specialists evaluating patients with Goldenhar syndrome should be aware of the possibility of inner ear malformations, which could be diagnosed earlier with appropriate imaging studies.
ATLAS-plus: Multimedia Instruction in Embryology, Gross Anatomy, and Histology

PubMed Central

Chapman, CM; Miller, JG; Bush, LC; Bruenger, JA; Wysor, WJ; Meininger, ET; Wolf, FM; Fischer, TV; Beaudoin, AR; Burkel, WE; MacCallum, DK; Fisher, DL; Carlson, BM

1992-01-01

ATLAS-plus [Advanced Tools for Learning Anatomical Structure] is a multimedia program used to assist in the teaching of anatomy at the University of Michigan Medical School. ATLAS-plus contains three courses: Histology, Embryology, and Gross Anatomy. In addition to the three courses, a glossary containing terms from the three courses is available. All three courses and the glossary are accessible in the ATLAS-plus environment. The ATLAS-plus environment provides a consistent set of tools and options so that the user can navigate easily and intelligently in and between the various courses and modules in the ATLAS-plus world. The program is a collaboration between anatomy and cell biology faculty, medical students, graphic artists, systems analysts, and instructional designers. PMID:1482964
Giant serous cystadenoma arising from an accessory ovary in a morbidly obese 11-year-old girl: a case report.

PubMed

Sharatz, Steven M; Treviño, Taína A; Rodriguez, Luís; West, Jared H

2008-01-18

Ectopic ovarian tissue is an unusual entity, especially if it is an isolated finding thought to be of embryological origin. An 11-year-old, morbidly obese female presented with left flank pain, nausea, and irregular menses. Various diagnostic procedures suggested a large ovarian cyst, and surgical resection was performed. Histologically, the resected mass was not of tubal origin as suspected, but a serous cystadenoma arising from ovarian tissue. The patient's two normal, eutopic ovaries were completely uninvolved and unaffected. A tumor arising from ectopic ovarian tissue of embryological origin seems the most likely explanation. We suggest refining the descriptive nomenclature so as to more precisely characterize the various presentations of ovarian ectopia.
Primary retroperitoneal seminoma - embryology, histopathology and treatment particularities.

PubMed

Gîngu, Constantin Virgil; Mihai, Mihaela; Baston, Cătălin; Crăsneanu, Mugurel Alexandru; Dick, Alexandru Vladimir; Olaru, Vlad; Sinescu, Ioanel

2016-01-01

Retroperitoneal seminoma is a very rare form of cancer, with embryological origin represented by primordial germ cells from the urogenital ridges left behind during the fetal development. Extragenital germ cell tumors can also occur in the mediastinum or the pineal gland. The aim of this paper is to outline the particularities and draw embryological, histopatological and treatment conclusions regarding extragonadal germ cell tumors. A 43-year-old patient without any additional pathology was admitted for anemia of unknown etiology. The clinical examination revealed through deep abdominal palpation a mass in the left flank, and normal testes. Thoraco-abdomino-pelvic computed tomography (CT) scan showed a large retroperitoneal tumor adjacent to the great vessels in the left lumbo-iliac region. The blood work revealed just a low hemoglobin and hematocrit. With the established diagnosis of retroperitoneal tumor, radical surgical removal was decided. During the surgery, we were required to dissect a large solid encapsulated tumor mass from the aorta and the common iliac artery, starting at the renal pedicle all the way to the left iliac bifurcation. The surgical access was obtained through a transperitoneal left subcostal incision prolonged pararectally. Histopathological and immunohistochemical studies revealed a seminoma of the usual type. After the histological findings, the patient's tumor markers were investigated (LDH - lactate dehydrogenase, βHCG - beta-human chorionic gonadotropin, αFP - alpha-fetoprotein), all values being within normal ranges. In addition, the left testicle was thoroughly reexamined, clinically, through ultrasound and magnetic resonance imaging (MRI) scans, and no abnormalities were observed. After the surgery, the patient followed three courses of chemotherapy (BEP - Bleomycin, Etoposide and Cisplatin). The CT scan done 24 months after surgery found no signs of local or distant tumor recurrence. The patient entered a follow-up schedule consisting of periodical clinical, serological and imagistic evaluations. Primary retroperitoneal seminoma is a rare entity that must be taken into account when treating a retroperitoneal tumor. It develops out of the urogenital ridge, while the testes are normal. Thorough testicular evaluation (clinical, ultrasound and serum markers) is mandatory in all retroperitoneal tumors. The histopathological analysis is crucial for an accurate diagnosis and a proper management strategy. Through radical surgery and chemotherapy, the patients that are diagnosed prior to massive visceral metastatic dissemination can be cured.
Embryological exposure to valproic acid induces social interaction deficits in zebrafish (Danio rerio): A developmental behavior analysis.

PubMed

Zimmermann, Fernanda Francine; Gaspary, Karina Vidarte; Leite, Carlos Eduardo; De Paula Cognato, Giana; Bonan, Carla Denise

2015-01-01

Changes in social behavior are associated with brain disorders, including mood disorders, stress, schizophrenia, Alzheimer's disease, and autism spectrum disorders (ASD). Autism is a complex neurodevelopmental disorder characterized by deficits in social interaction, impaired communication, anxiety, hyperactivity, and the presence of restricted interests. Zebrafish is one of the most social vertebrates used as a model in biomedical research, contributing to an understanding of the mechanisms that underlie social behavior. Valproic acid (VPA) is used as an anti-epileptic drug and mood stabilizer; however, prenatal VPA exposure in humans has been associated with an increased incidence of autism and it can also affect fetal brain development. Therefore, we conducted a behavioral screening at different periods of zebrafish development at 6, 30, 70, and 120dpf (days postfertilization) after VPA exposure in the early development stage to investigate social behavior, locomotion, aggression, and anxiety. VPA (48μM) exposure during the first 48hpf (hours postfertilization) did not promote changes on survival, morphology, and hatching rate at 24hpf, 48hpf, and 72hpf. The behavioral patterns suggest that VPA exposure induces changes in locomotor activity and anxiety at different developmental periods in zebrafish. Furthermore, a social interaction deficit is present at 70dpf and 120dpf. VPA exposure did not affect aggression in the adult stage at 70dpf and 120dpf. This is the first study that demonstrated zebrafish exposed to VPA during the first 48h of development exhibit deficits in social interaction, anxiety, and hyperactivity at different developmental periods. Copyright © 2015 Elsevier Inc. All rights reserved.
Dysregulation of the PDGFRA gene causes inflow tract anomalies including TAPVR: integrating evidence from human genetics and model organisms

PubMed Central

Bleyl, Steven B.; Saijoh, Yukio; Bax, Noortje A.M.; Gittenberger-de Groot, Adriana C.; Wisse, Lambertus J.; Chapman, Susan C.; Hunter, Jennifer; Shiratori, Hidetaka; Hamada, Hiroshi; Yamada, Shigehito; Shiota, Kohei; Klewer, Scott E.; Leppert, Mark F.; Schoenwolf, Gary C.

2010-01-01

Total anomalous pulmonary venous return (TAPVR) is a congenital heart defect inherited via complex genetic and/or environmental factors. We report detailed mapping in extended TAPVR kindreds and mutation analysis in TAPVR patients that implicate the PDGFRA gene in the development of TAPVR. Gene expression studies in mouse and chick embryos for both the Pdgfra receptor and its ligand Pdgf-a show temporal and spatial patterns consistent with a role in pulmonary vein (PV) development. We used an in ovo function blocking assay in chick and a conditional knockout approach in mouse to knock down Pdgfra expression in the developing venous pole during the period of PV formation. We observed that loss of PDGFRA function in both organisms causes TAPVR with low penetrance (∼7%) reminiscent of that observed in our human TAPVR kindreds. Intermediate inflow tract anomalies occurred in a higher percentage of embryos (∼30%), suggesting that TAPVR occurs at one end of a spectrum of defects. We show that the anomalous pulmonary venous connection seen in chick and mouse is highly similar to TAPVR discovered in an abnormal early stage embryo from the Kyoto human embryo collection. Whereas the embryology of the normal venous pole and PV is becoming understood, little is known about the embryogenesis or molecular pathogenesis of TAPVR. These models of TAPVR provide important insight into the pathogenesis of PV defects. Taken together, these data from human genetics and animal models support a role for PDGF-signaling in normal PV development, and in the pathogenesis of TAPVR. PMID:20071345
Tracheoesophageal fistula and esophageal atresia repair

MedlinePlus

Madanick R, Orlando RC. Anatomy, histology, embryology, and developmental anomalies of the esophagus. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver ...
Development of the spinal cord and peripheral nervous system in platypus (Ornithorhynchus anatinus) and short-beaked echidna (Tachyglossus aculeatus).

PubMed

Ashwell, Ken W S

2012-01-01

The modern monotremes (platypus and echidnas) are characterized by development of their young in a leathery egg that is laid into a nest or abdominal pouch. At hatching, the young are externally immature, with forelimbs capable of digitopalmar prehension, but hindlimbs little advanced beyond limb buds. The embryological collections at the Museum für Naturkunde in Berlin were used to examine the development of the spinal cord and early peripheral nervous system in developing monotremes and to correlate this with known behavioural development. Ventral root outgrowth to the bases of both the fore- and hindlimbs occurs at 6.0 mm crown-rump length (CRL), but invasion of both limbs does not happen until about 8.0-8.5 mm CRL. Differentiation of the ventral horn precedes the dorsal horn during incubation and separate medial and lateral motor columns can be distinguished before hatching. Rexed's laminae begin to appear in the dorsal horn in the first week after hatching, and gracile and cuneate fasciculi emerge during the first two post-hatching months. Qualitative and quantitative comparisons of the structure of the cervicothoracic junction spinal cord in the two monotremes with that in a diprotodont marsupial (the brush-tailed possum, Trichosurus vulpecula) of similar size at birth, did not reveal any significant structural differences between the monotremes and the marsupial. The precocious development of motor systems in the monotreme spinal cord is consistent with the behavioural requirements of the peri-hatching period, that is, rupture of embryonic membranes and egg, and digitopalmar prehension to grasp maternal hair or nest material.
Effects of salinity and sea salt type on egg activation, fertilization, buoyancy and early embryology of European eel, Anguilla anguilla.

PubMed

Sørensen, Sune Riis; Butts, Ian Anthony Ernest; Munk, Peter; Tomkiewicz, Jonna

2016-02-01

Improper activation and swelling of in vitro produced eggs of European eel, Anguilla anguilla, has been shown to negatively affect embryonic development and hatching. We investigated this phenomenon by examining the effects of salinity and sea salt type on egg dimensions, cell cleavage patterns and egg buoyancy. Egg diameter after activation, using natural seawater adjusted to different salinities, varied among female eels, but no consistent pattern emerged. Activation salinities between 30-40 practical salinity unit (psu) produced higher quality eggs and generally larger egg diameters. Chorion diameters reached maximal values of 1642 ± 8 μm at 35 psu. A positive relationship was found between egg neutral buoyancy and activation salinity. Nine salt types were investigated as activation and incubation media. Five of these types induced a substantial perivitelline space (PVS), leading to large egg sizes, while the remaining four salt types resulted in smaller eggs. All salt types except NaCl treatments led to high fertilization rates and had no effect on fertilization success as well as egg neutral buoyancies at 7 h post-fertilization. The study points to the importance of considering ionic composition of the media when rearing fish eggs and further studies are encouraged.
Restructuring a basic science course for core competencies: an example from anatomy teaching.

PubMed

Gregory, Jeremy K; Lachman, Nirusha; Camp, Christopher L; Chen, Laura P; Pawlina, Wojciech

2009-09-01

Medical schools revise their curricula in order to develop physicians best skilled to serve the public's needs. To ensure a smooth transition to residency programs, undergraduate medical education is often driven by the six core competencies endorsed by the Accreditation Council for Graduate Medical Education (ACGME): patient care, medical knowledge, practice-based learning, interpersonal skills, professionalism, and systems-based practice. Recent curricular redesign at Mayo Medical School provided an opportunity to restructure anatomy education and integrate radiology with first-year gross and developmental anatomy. The resulting 6-week (120-contact-hour) human structure block provides students with opportunities to learn gross anatomy through dissection, radiologic imaging, and embryologic correlation. We report more than 20 educational interventions from the human structure block that may serve as a model for incorporating the ACGME core competencies into basic science and early medical education. The block emphasizes clinically-oriented anatomy, invites self- and peer-evaluation, provides daily formative feedback through an audience response system, and employs team-based learning. The course includes didactic briefing sessions and roles for students as teachers, leaders, and collaborators. Third-year medical students serve as teaching assistants. With its clinical focus and competency-based design, the human structure block connects basic science with best-practice clinical medicine.
Clinicopathologic features and surgical management of primary umbilical melanoma: a case series.

PubMed

Di Monta, Gianluca; Caracò, Corrado; Marone, Ugo; Grimaldi, Antonio Maria; Anniciello, Anna Maria; Di Marzo, Massimiliano; Simeone, Ester; Mori, Stefano

2015-04-15

Primary umbilical melanoma is an uncommon tumor that is poorly described in the medical literature. The umbilical region is a particular anatomic site owing to the presence of embryonal remnants, which can be a potential metastatic pathway, as well as the braided lymphatic network drainage. Hence, primary malignant neoplasms affecting the umbilicus require a different and more radical surgical approach compared with other melanomas. In this report, we describe a series of three patients of Caucasian ethnicity who presented with primary umbilical melanoma at the National Cancer Institute of Naples, Italy. All patients underwent wide excision of the tumor including the underlying peritoneum. No surgical complications, either immediate or delayed, were observed in any of the patients. Sentinel lymph node biopsy was negative in two cases. Two of the patients developed metastatic disease and died after systemic medical therapy. The other patient is currently in follow-up, and remains disease-free after 21 months. The umbilicus has vascular and embryological connections with the underlying peritoneum, so that early visceral involvement is more likely to occur with primary umbilical melanomas. As such, tumor resection including the underlying peritoneum is required to avoid local relapse, whilst sentinel lymph node biopsy appears to be of poor diagnostic value.
FOXP2 and the neuroanatomy of speech and language.

PubMed

Vargha-Khadem, Faraneh; Gadian, David G; Copp, Andrew; Mishkin, Mortimer

2005-02-01

That speech and language are innate capacities of the human brain has long been widely accepted, but only recently has an entry point into the genetic basis of these remarkable faculties been found. The discovery of a mutation in FOXP2 in a family with a speech and language disorder has enabled neuroscientists to trace the neural expression of this gene during embryological development, track the effects of this gene mutation on brain structure and function, and so begin to decipher that part of our neural inheritance that culminates in articulate speech.
[A persistent sciatic artery revealed by acute ischemia of the right lower limb: A case report].

PubMed

Benleghib, N; Boukabache, L; Aziza, B; Boudine, L; Boulacel, A; Boussafsaf, B

2017-09-19

The Persistent Sciatic Artery (PSA) is an unusual anatomical variation due to the persistence of an embryological artery, which should disappear before the 3rd month of intrauterine life. The reported case is that of a woman who developed an acute ischemia of the right lower limb, revealing the presence of persistent sciatic artery. Diagnosis was made only belatedly by means of angio-CT. The amputation was the inevitable choice of treatment. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Appendicoumbilical Fistula: A Rare Reason for Neonatal Umbilical Mass

PubMed Central

Cevik, M.; Boleken, M. E.; Kadıoglu, E.

2011-01-01

The normal umbilicus is a simple structure, but the intrauterine development of the umbilicus is highly complex. Neonatal umbilical mass anomalies usually represent failure of obliteration of the vitelline duct or the allantois which results in persistence of remnants, which can lead to a wide variety of disorders. In this paper, we present a case of an appendicoumbilical fistula in a neonate along with the differential diagnosis and management options. Embryologic explanation of the etiology was discussed with the possible association with different forms of malpositioning and rotation of the gut. PMID:21629815

Appendicoumbilical fistula: a rare reason for neonatal umbilical mass.

PubMed

Cevik, M; Boleken, M E; Kadıoglu, E

2011-01-01

The normal umbilicus is a simple structure, but the intrauterine development of the umbilicus is highly complex. Neonatal umbilical mass anomalies usually represent failure of obliteration of the vitelline duct or the allantois which results in persistence of remnants, which can lead to a wide variety of disorders. In this paper, we present a case of an appendicoumbilical fistula in a neonate along with the differential diagnosis and management options. Embryologic explanation of the etiology was discussed with the possible association with different forms of malpositioning and rotation of the gut.
Anterior spinal and bulbar artery supply to the posterior inferior cerebellar artery revealed by a ruptured aneurysm: case report.

PubMed

Gabrieli, Joseph; Sourour, Nader-Antoine; Chauvet, Dorian; Di Maria, Federico; Chiras, Jacques; Clarençon, Frédéric

2017-02-01

The posterior inferior cerebellar artery (PICA) is a vessel located between the intra- and extracranial circulation. The artery is characterized by a complex embryological development and numerous anatomical variants. The authors present a case of the PICA supplied by both a hypertrophic anterior spinal artery and a hypoplastic bulbar artery. This unusual arrangement somehow completes the list of previously published variants, and the spontaneous rupture of a related aneurysm confirmed the fragility of this network. The authors discuss anatomical and treatment considerations.
Ontogenesis of mammals in microgravity

NASA Technical Reports Server (NTRS)

Gazenko, O. G. (Editor)

1993-01-01

This report is an English translation of a Russian report prepared by a group of authors from the USSR, Bulgaria, Hungary, the GDR, Poland, Czechoslovakia, France, and the USA. It presents results of the first microgravity experiment on mammalian embryology performed during the flight of the biosatellite Cosmos-1514 and in ground-based simulation studies. An overview is provided of the data available about the role of gravity in animal growth and development, and future studies into this problem are discussed. A new introduction has been provided for the English version.
STS-47 MS Jemison trains in SLJ module at MSFC Payload Crew Training Complex

NASA Technical Reports Server (NTRS)

1992-01-01

STS-47 Endeavour, Orbiter Vehicle (OV) 105, Mission Specialist (MS) Mae C. Jemison, wearing Autogenic Feedback Training System 2 suit, works with the Frog Embryology Experiment in a General Purpose Workstation (GPWS) in the Spacelab Japan (SLJ) module mockup at the Payload Crew Training Complex. The experiment will study the effects of weightlessness on the development of frog eggs fertilized in space. The Payload Crew Training Complex is located at the Marshall Space Flight Center (MSFC) in Huntsville, Alabama. View provided with alternate number 92P-139.
Embryology and anatomy of the vulva: the female orgasm and women's sexual health.

PubMed

Puppo, Vincenzo

2011-01-01

Sexual health is vital to overall well-being. Orgasm is a normal psycho-physiological function of human beings and every woman has the right to feel sexual pleasure. The anatomy of the vulva and of the female erectile organs (trigger of orgasm) is described in human anatomy textbooks. Female sexual physiology was first described in Dickinson's textbook in 1949 and subsequently by Masters and Johnson in 1966. During women's sexual response, changes occur in the congestive structures that are essential to the understanding of women's sexual response and specifically of their orgasm. Female and male external genital organs arise from the same embryologic structures, i.e. phallus, urogenital folds, urogenital sinus and labioscrotal swellings. The vulva is formed by the labia majora and vestibule, with its erectile apparatus: clitoris (glans, body, crura), labia minora, vestibular bulbs and corpus spongiosum. Grafenberg, in 1950, discovered no "G-spot" and did not report an orgasm of the intraurethral glands. The hypothetical area named "G-spot" should not be defined with Grafenberg's name. The female orgasm should be a normal phase of the sexual response cycle, which is possible to achieve by all healthy women with effective sexual stimulation. Knowledge of the embryology, anatomy and physiology of the female erectile organs are important in the field of women's sexual health. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.
Decreased Sperm Motility Retarded ICSI Fertilization Rate in Severe Oligozoospermia but Good-Quality Embryo Transfer Had Achieved the Prospective Clinical Outcomes.

PubMed

Zheng, Jufeng; Lu, Yongning; Qu, Xianqin; Wang, Peng; Zhao, Luiwen; Gao, Minzhi; Shi, Huijuan; Jin, Xingliang

Spermatozoa motility is the critical parameter to affect the treatment outcomes during assisted reproductive technologies (ART), but its reproductive capability remains a little informed in condition of severe male factor infertility. This retrospective cohort study aimed to evaluate the effects of reduced sperm motility on the embryological and clinical outcomes in intra-cytoplasmic sperm injection (ICSI) treatment of severe oligozoospermia. 966 cycles (812 couples) of severe oligozoospermia diagnosed by spermatozoa count ≤ 5 × 106/mL and motile spermatozoa ≤ 2 × 106/mL were divided into four groups in according to the number of motile spermatozoa in one ejaculate on the day of oocyte retrieval (Group B-E). The control (Group A) was 188 cycles of moderate oligozoospermia with spermatozoa count > 5 × 106/mL and motile spermatozoa > 2 × 106/mL. All female partners were younger than 35 years of age. Logistic regression analyzed embryological outcomes (the rates of fertilization, cleavage and good-quality embryo) and clinical outcomes (the rates of pregnancy, implantation, early miscarriage and live birth). Quality of embryo transfer (ET) was divided into three classes as continuous factor to test the effects of embryo quality on clinical outcomes. The reduction in the number of motile sperm in four groups of severe oligozoospermia gave rise to comparable inability of the fertilization (p < 0.001) and a decreased rate of good-quality embryo at Day 3 (p < 0.001) by compared to the control. The cleavage rate of the derived zygotes was similar to the control. ET classes significantly affected the clinical outcomes (p < 0.001). Class I ET gave rise to similar rates of clinical outcomes between five groups, but Class II and Class III ET retarded the rates of pregnancy, implantation and live birth and this particularly occurred in Group C, D and E. The rate of early miscarriage was not comparably different between groups. Overall rates in all groups were 41.26% clinical pregnancy, 25.74% implantation and 36.32% live birth, which gave live birth to 252 girls and 252 boys. The reduction of motile spermatozoa in severe oligozoospermia decreased the rates of fertilization and good-quality embryo. Obtaining and transfer of good-quality embryos was the good prognostic to achieve prospective clinical outcomes regardless of the severity of oligozoospermia.
Integration of microfluidics in animal in vitro embryo production.

PubMed

Wheeler, M B; Rubessa, M

2017-04-01

The in vitro production of livestock embryos is central to several areas of animal biotechnology. Further, the use of in vitro embryo manipulation is expanding as new applications emerge. ARTs find direct applications in increasing genetic quality of livestock, producing transgenic animals, cloning, artificial insemination, reducing disease transmission, preserving endangered germplasm, producing chimeric animals for disease research, and treating infertility. Whereas new techniques such as nuclear transfer and intracytoplasmic sperm injection are now commonly used, basic embryo culture procedures remain the limiting step to the development of these techniques. Research over the past 2 decades focusing on improving the culture medium has greatly improved in vitro development of embryos. However, cleavage rates and viability of these embryos is reduced compared with in vivo indicating that present in vitro systems are still not optimal. Furthermore, the methods of handling mammalian oocytes and embryos have changed little in recent decades. While pipetting techniques have served embryology well in the past, advanced handling and manipulation technologies will be required to efficiently implement and commercialize the basic biological advances made in recent years. Microfluidic systems can be used to handle gametes, mature oocytes, culture embryos, and perform other basic procedures in a microenvironment that more closely mimic in vivo conditions. The use of microfluidic technologies to fabricate microscale devices has being investigated to overcome this obstacle. In this review, we summarize the development and testing of microfabricated fluidic systems with feature sizes similar to the diameter of an embryo for in vitro production of pre-implantation mammalian embryos. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
The presentation and management of complex female genital malformations.

PubMed

Acién, Pedro; Acién, Maribel

2016-01-01

Common uterine anomalies are important owing to their impact on fertility, and complex mesonephric anomalies and certain Müllerian malformations are particularly important because they cause serious clinical symptoms and affect woman's quality of life, in addition to creating fertility problems. In these cases of complex female genital tract malformations, a correct diagnosis is essential to avoid inappropriate and/or unnecessary surgery. Therefore, acquiring and applying the appropriate embryological knowledge, management and therapy is a challenge for gynaecologists. Here, we considered complex malformations to be obstructive anomalies and/or those associated with cloacal and urogenital sinus anomalies, urinary and/or extragenital anomalies, or other clinical implications or symptoms creating a difficult differential diagnosis. A diligent and comprehensive search of PubMed and Scopus was performed for all studies published from 1 January 2011 to 15 April 2015 (then updated up to September 2015) using the following search terms: 'management' in combination with either 'female genital malformations' or 'female genital tract anomalies' or 'Müllerian anomalies'. The MeSH terms 'renal agenesis', 'hydrocolpos', 'obstructed hemivagina' 'cervicovaginal agenesis or atresia', 'vaginal agenesis or atresia', 'Herlyn-Werner-Wunderlich syndrome', 'uterine duplication' and 'cloacal anomalies' were also used to compile a list of all publications containing these terms since 2011. The basic embryological considerations for understanding female genitourinary malformations were also revealed. Based on our experience and the updated literature review, we studied the definition and classification of the complex malformations, and we analysed the clinical presentation and different therapeutic strategies for each anomaly, including the embryological and clinical classification of female genitourinary malformations. From 755 search retrieved references, 230 articles were analysed and 120 studied in detail. They were added to those included in a previous systematic review. Here, we report the clinical presentation and management of: agenesis or hypoplasia of one urogenital ridge; unilateral renal agenesis and ipsilateral blind or obstructed hemivagina or unilateral cervicovaginal agenesis; cavitated and non-communicating uterine horns and Müllerian atresias or agenesis, including Rokitansky syndrome; anomalies of the cloaca and urogenital sinus, including congenital vagino-vesical fistulas and cloacal anomalies; malformative combinations and other complex malformations. The clinical symptoms and therapeutic strategies for each complex genitourinary malformation are discussed. In general, surgical techniques to correct genital malformations depend on the type of anomaly, its complexity, the patient's symptoms and the correct embryological interpretation of the anomaly. Most anomalies can typically be resolved vaginally or by hysteroscopy, but laparoscopy or laparotomy is often required as well. We also include additional discussion of the catalogue and classification systems for female genital malformations, the systematic association between renal agenesis and ipsilateral genital malformation, and accessory and cavitated uterine masses. Knowledge of the correct genitourinary embryology is essential for the understanding, study, diagnosis and subsequent treatment of genital malformations, especially complex ones and those that lead to gynaecological and reproductive problems, particularly in young patients. Some anomalies may require complex surgery involving multiple specialties, and patients should therefore be referred to centres that have experience in treating complex genital malformations. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Pleurodeles waltl, amphibian, Urodele, is a suitable biological model for embryological and physiological space experiments on a vertebrate

NASA Astrophysics Data System (ADS)

Gualandris-Parisot, L.; Husson, D.; Foulquier, F.; Kan, P.; Davet, J.; Aimar, C.; Dournon, C.; Duprat, A. M.

2001-01-01

Pleurodeles waltl (amphibian, Urodele) is an appropriate biological model for space experiments on a vertebrate. One reason for interest in this animal concerns the study of the effects of absence of gravity on embryonic development. First, after mating (on Earth) the females retain live, functional sperm in their cloacum for up to 5 months, allowing normal in vivo fertilisation after hormonal stimulation. Second, their development is slow, which allows analyses of all the key stages of ontogenesis from the oocyte to swimming tailbud embryos or larvae. We have performed detailed studies and analyses of the effects of weightlessness on amphibian Pleurodeles embryos, fertilised and allowed to develop until the swimming larvae stage. These experiments were performed in space during three missions on the MIR-station: FERTILE I, FERTILE II and NEUROGENESIS respectively in 1996, 1998 and 1999. We show that in microgravity abnormalities appeared at specific stages of development compared to 1g-centrifuge control embryos and 1g-ground control embryos. In this report we describe abnormalities occurring in the central nervous system. These modifications occur during the neurulation process (delay in the closure of the neural tube and failure of closure of this tube in the cephalic area) and at the early tailbud stage (microcephaly observed in 40% of the microgravity-embryos). However, if acephalic and microcephalic embryos are not taken into account, these abnormalities did not disturb further morphological, biochemical and functional development and the embryos were able to regulate and a majority of normal hatching and swimming larvae were obtained in weightlessness with a developmental time-course equivalent to that of 1g-centrifuge control embryos (on the MIR station) and 1g-ground control embryos.
Pitx2c attenuation results in cardiac defects and abnormalities of intestinal orientation in developing Xenopus laevis.

PubMed

Dagle, John M; Sabel, Jaime L; Littig, Jennifer L; Sutherland, Lillian B; Kolker, Sandra J; Weeks, Daniel L

2003-10-15

The experimental manipulation of early embryologic events, resulting in the misexpression of the homeobox transcription factor pitx2, is associated with subsequent defects of laterality in a number of vertebrate systems. To clarify the role of one pitx2 isoform, pitx2c, in determining the left-right axis of amphibian embryos, we examined the heart and gut morphology of Xenopus laevis embryos after attenuating pitx2c mRNA levels using chemically modified antisense oligonucleotides. We demonstrate that the partial depletion of pitx2c mRNA in these embryos results in alteration of both cardiac morphology and intestinal coiling. The most common cardiac abnormality seen was a failure of rightward migration of the outflow tract, while the most common intestinal laterality phenotype seen was a full reversal in the direction of coiling, each present in 23% of embryos injected with the pitx2c antisense oligonucleotide. An abnormality in either the heart or gut further predisposed to a malformation in the other. In addition, a number of other cardiac anomalies were observed after pitx2c mRNA attenuation, including abnormalities of atrial septation, extracellular matrix restriction, relative atrial-ventricular chamber positioning, and restriction of ventricular development. Many of these findings correlate with cardiac defects previously reported in pitx2 null and hypomorphic mice, but can now be assigned specifically to attenuation of the pitx2c isoform in Xenopus.
The embryologic development of the human external auditory meatus. Preliminary report.

PubMed

Nishimura, Y; Kumoi, T

1992-01-01

During the final period of embryogenesis, a funnel-shaped tube continues medially into the mesenchymal tissue forming a curved path. Although this may sound simple, the development occurring during early fetal life is in fact very complex. At first, ectodermal cells proliferate to fill the lumen of the meatus, forming the meatal plug, and then at 10 weeks the bottom of the plug extends in a disc-like fashion, so that in the horizontal plane the meatus is boot-shaped with a narrow neck and the sole of the meatal plug spreading widely to form the future tympanic membrane medially. At the same time, the plug in the proximal portion of the neck starts to be resorbed. In the 13-week fetus, the disc-like plug begins to show signs of its final destiny; the innermost surface of the plug in contact with the anlage of the malleus is ready to contribute to the formation of the tympanic membrane. In the 15-week fetus, the innermost portion of the disc-like plug splits, leaving a thin ectodermal cell layer of immature tympanic membrane. The neck of the boot forms the border between the primary and secondary meatus, and is the last part to split. In the 16.5-week fetus, the meatus is fully patent throughout its entire length, although the lumen is still narrow and curved. In the 18-week fetus, the meatus is already fully expanded to its complete form.
Distinct development of the trigeminal sensory nuclei in platypus and echidna.

PubMed

Ashwell, Ken W S; Hardman, Craig D

2012-01-01

Both lineages of the modern monotremes have been reported to be capable of electroreception using the trigeminal pathways and it has been argued that electroreception arose in an aquatic platypus-like ancestor of both modern monotreme groups. On the other hand, the trigeminal sensory nuclear complex of the platypus is highly modified for processing tactile and electrosensory information from the bill, whereas the trigeminal sensory nuclear complex of the short-beaked echidna (Tachyglossus aculeatus) is not particularly specialized. If the common ancestor for both platypus and echidna were an electroreceptively and trigeminally specialized aquatic feeder, one would expect the early stages of development of the trigeminal sensory nuclei in both species to show evidence of structural specialization from the outset. To determine whether this is the case, we examined the development of the trigeminal sensory nuclei in the platypus and short-beaked echidna using the Hill and Hubrecht embryological collections. We found that the highly specialized features of the platypus trigeminal sensory nuclei (i.e. the large size of the principal nucleus and oral part of the spinal trigeminal nuclear complex, and the presence of a dorsolateral parvicellular segment in the principal nucleus) appear around the time of hatching in the platypus, but are never seen at any stage in the echidna. Our findings support the proposition that the modern echidna and platypus are derived from a common ancestor with only minimal trigeminal specialization and that the peculiar anatomy of the trigeminal sensory nuclei in the modern platypus emerged in the ornithorhynchids after divergence from the tachyglossids. Copyright © 2012 S. Karger AG, Basel.
Preliminary embryological study of the radiological concept of retroperitoneal interfascial planes: what are the interfascial planes?

PubMed

Ishikawa, Kazuo; Nakao, Shota; Murakami, Gen; Rodríguez-Vázquez, Jose Francisco; Matsuoka, Tetsuya; Nakamuro, Makoto; Shimazu, Takeshi

2014-12-01

Recently, the radiological concept of retroperitoneal interfascial planes has been widely accepted to explain the extension of retroperitoneal pathologies. This study aimed to explore embryologically based corroborative evidence, which remains to be elucidated, for this concept. Using serial or semi-serial transverse sections from 29 human fetuses at the 5th-25th week of fetal age, we microscopically observed the development of the retroperitoneal fasciae and other structures in the retroperitoneal connective tissue. A hypothesis for the formation of the interfascial planes was generated from the developmental study and analysis of retroperitoneal fasciae in computed tomography images from 224 patients. Whereas the loose connective tissue was uniformly distributed in the retroperitoneum by the 9th week, the primitive renal and transversalis fasciae appeared at the 10th-12th week, as previous research has noted. By the 23rd week, the renal fascia, transversalis fascia, and primitive adipose tissue of the flank pad emerged. In addition, the primitive lateroconal fascia, which runs parallel to and close to the posterior renal fascia, emerged between the renal fascia and the adipose tissue of the flank pad. Conversely, pre-existing loose connective tissue was sandwiched between the opposing fasciae and was compressed and narrowed by the developing organs and fatty tissues. Through this developmental study, we provided the hypothesis that the compressed loose connective tissue and both opposed fasciae compose the interfascial planes. Analysis of the thickened retroperitoneal fasciae in computed tomography images supported this hypothesis. Further developmental or histological studies are required to verify our hypothesis.
The anatomy, affinity, and phylogenetic significance of Markuelia.

PubMed

Dong, Xi-Ping; Donoghue, Philip C J; Cunningham, John A; Liu, Jian-Bo; Cheng, Hong

2005-01-01

The fossil record provides a paucity of data on the development of extinct organisms, particularly for their embryology. The recovery of fossilized embryos heralds new insight into the evolution of development but advances are limited by an almost complete absence of phylogenetic constraint. Markuelia is an exception to this, known from cleavage and pre-hatchling stages as a vermiform and profusely annulated direct-developing bilaterian with terminal circumoral and posterior radial arrays of spines. Phylogenetic analyses have hitherto suggested assignment to stem-Scalidophora (phyla Kinorhyncha, Loricifera, Priapulida). We test this assumption with additional data and through the inclusion of additional taxa. The available evidence supports stem-Scalidophora affinity, leading to the conclusion that scalidophorans, cyclonerualians, and ecdysozoans are primitive direct developers, and the likelihood that scalidophorans are primitively metameric.
Skull Development, Ossification Pattern, and Adult Shape in the Emerging Lizard Model Organism Pogona vitticeps: A Comparative Analysis With Other Squamates.

PubMed

Ollonen, Joni; Da Silva, Filipe O; Mahlow, Kristin; Di-Poï, Nicolas

2018-01-01

The rise of the Evo-Devo field and the development of multidisciplinary research tools at various levels of biological organization have led to a growing interest in researching for new non-model organisms. Squamates (lizards and snakes) are particularly important for understanding fundamental questions about the evolution of vertebrates because of their high diversity and evolutionary innovations and adaptations that portrait a striking body plan change that reached its extreme in snakes. Yet, little is known about the intricate connection between phenotype and genotype in squamates, partly due to limited developmental knowledge and incomplete characterization of embryonic development. Surprisingly, squamate models have received limited attention in comparative developmental studies, and only a few species examined so far can be considered as representative and appropriate model organism for mechanistic Evo-Devo studies. Fortunately, the agamid lizard Pogona vitticeps (central bearded dragon) is one of the most popular, domesticated reptile species with both a well-established history in captivity and key advantages for research, thus forming an ideal laboratory model system and justifying his recent use in reptile biology research. We first report here the complete post-oviposition embryonic development for P. vitticeps based on standardized staging systems and external morphological characters previously defined for squamates. Whereas the overall morphological development follows the general trends observed in other squamates, our comparisons indicate major differences in the developmental sequence of several tissues, including early craniofacial characters. Detailed analysis of both embryonic skull development and adult skull shape, using a comparative approach integrating CT-scans and gene expression studies in P. vitticeps as well as comparative embryology and 3D geometric morphometrics in a large dataset of lizards and snakes, highlights the extreme adult skull shape of P. vitticeps and further indicates that heterochrony has played a key role in the early development and ossification of squamate skull bones. Such detailed studies of embryonic character development, craniofacial patterning, and bone formation are essential for the establishment of well-selected squamate species as Evo-Devo model organisms. We expect that P. vitticeps will continue to emerge as a new attractive model organism for understanding developmental and molecular processes underlying tissue formation, morphology, and evolution.
Skull Development, Ossification Pattern, and Adult Shape in the Emerging Lizard Model Organism Pogona vitticeps: A Comparative Analysis With Other Squamates

PubMed Central

Ollonen, Joni; Da Silva, Filipe O.; Mahlow, Kristin; Di-Poï, Nicolas

2018-01-01

The rise of the Evo-Devo field and the development of multidisciplinary research tools at various levels of biological organization have led to a growing interest in researching for new non-model organisms. Squamates (lizards and snakes) are particularly important for understanding fundamental questions about the evolution of vertebrates because of their high diversity and evolutionary innovations and adaptations that portrait a striking body plan change that reached its extreme in snakes. Yet, little is known about the intricate connection between phenotype and genotype in squamates, partly due to limited developmental knowledge and incomplete characterization of embryonic development. Surprisingly, squamate models have received limited attention in comparative developmental studies, and only a few species examined so far can be considered as representative and appropriate model organism for mechanistic Evo-Devo studies. Fortunately, the agamid lizard Pogona vitticeps (central bearded dragon) is one of the most popular, domesticated reptile species with both a well-established history in captivity and key advantages for research, thus forming an ideal laboratory model system and justifying his recent use in reptile biology research. We first report here the complete post-oviposition embryonic development for P. vitticeps based on standardized staging systems and external morphological characters previously defined for squamates. Whereas the overall morphological development follows the general trends observed in other squamates, our comparisons indicate major differences in the developmental sequence of several tissues, including early craniofacial characters. Detailed analysis of both embryonic skull development and adult skull shape, using a comparative approach integrating CT-scans and gene expression studies in P. vitticeps as well as comparative embryology and 3D geometric morphometrics in a large dataset of lizards and snakes, highlights the extreme adult skull shape of P. vitticeps and further indicates that heterochrony has played a key role in the early development and ossification of squamate skull bones. Such detailed studies of embryonic character development, craniofacial patterning, and bone formation are essential for the establishment of well-selected squamate species as Evo-Devo model organisms. We expect that P. vitticeps will continue to emerge as a new attractive model organism for understanding developmental and molecular processes underlying tissue formation, morphology, and evolution. PMID:29643813
The Sea Urchin Embryo: A Remarkable Classroom Tool.

ERIC Educational Resources Information Center

Oppenheimer, Steven B.

1989-01-01

Discussed are the uses of sea urchins in research and their usefulness and advantages in the classroom investigation of embryology. Ideas for classroom activities and student research are presented. Lists 25 references. (CW)
Plato's Embryology.

PubMed

Wilberding, James

2015-01-01

Embryology was a subject that inspired great cross-disciplinary discussion in antiquity, and Plato's Timaeus made an important contribution to this discussion, though Plato's precise views have remained a matter of controversy, especially regarding three key questions pertaining to the generation and nature of the seed: whether there is a female seed; what the nature of seed is; and whether the seed contains a preformed human being. In this paper I argue that Plato's positions on these three issues can be adequately determined, even if some other aspects of his theory cannot. In particular, it is argued that (i) Plato subscribes to the encephalo-myelogenic theory of seed, though he places particular emphasis on the soul being the true seed; (ii) Plato is a two-seed theorist, yet the female seed appears to make no contribution to reproduction; and (iii) Plato cannot be an advocate of preformationism.
The intercalatus nucleus of Staderini.

PubMed

Cascella, Marco

2016-01-01

Rutilio Staderini was one of the leading Italian anatomists of the twentieth century, together with some scientists, such as Giulio Chiarugi, Giovanni Vitali, and others. He was also a member of a new generation of anatomists. They had continued the tradition of the most famous Italian scientists, which started from the Renaissance up until the nineteenth century. Although he carried out important studies of neuroanatomy and comparative anatomy, as well as embryology, his name is rarely remembered by most medical historians. His name is linked to the nucleus he discovered: the Staderini nucleus or intercalated nucleus, a collection of nerve cells in the medulla oblongata located lateral to the hypoglossal nucleus. This article focuses on the biography of the neuroanatomist as well as the nucleus that carries his name and his other research, especially on comparative anatomy and embryology.
Keratinous inclusion cyst of oesophagus: unusual finding

PubMed Central

Wan Abdul Rahman, Wan Faiziah; Mutum, Samarendra Singh; Fauzi, Mohd Hashairi

2013-01-01

Cysts of the oesophagus are unusual findings and they are classified according to the embryological site of origin. It may represent inclusion cysts, retention cysts and developmental cysts. We present a case of keratinous inclusion cyst of the lower oesophagus in a 71-year-old Malay woman who presented with dyspepsia and severe epigastric pain. An oesophago-gastro-duodenoscopy demonstrated a sliding hiatus hernia with whitish ulcer-like lesion at the lower oesophagus. Biopsy from the lesion revealed a keratinous inclusion cyst. The patient was given pantoprazole and put on regular follow-up for monitoring any other development. PMID:23878290

Complete dorsal pancreatic agenesis and unilateral renal agenesis.

PubMed

Moreira, Adriana; Carvalho, André; Portugal, Inês; Jesus, José Miguel

2018-02-01

Dorsal pancreatic agenesis is a very rare congenital anomaly. Unilateral renal agenesis, on the other hand, is a relatively common congenital anomaly, although its etiology is not fully understood. Renal and pancreatic embryologic development appears to be nonrelated. We report a case of a 34-year-old man who was referred to our hospital for evaluation of cholestasis and microalbuminuria. Ultrasound and magnetic resonance imaging examinations showed empty right renal fossa and absence of the pancreatic neck, body, and tail. Our case report is the second case of a dorsal pancreatic agenesis and unilateral renal agenesis in a young male patient.
Atlas of neuroanatomy with radiologic correlation and pathologic illustration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dublin, A.B.; Dublin, W.B.

1982-01-01

This atlas correlates gross neuroanatomic specimens with radiographs and computed tomographic scans. Pathologic specimens and radiographs are displayed in a similar manner. The first chapter, on embryology, shows the development of the telencephalon, diencephalon, mesencephalon, and metencephalon through a series of overlays. The anatomical section shows the surface of the brain, the ventricles and their adjacent structures, and the vascular system. CT anatomy is demonstrated by correlating CT scans with pathologic brain specimens cut in the axial plane. Pathologic changes associated with congenital malformations, injections, injuries, tumors, and other causes are demonstrated in the last six chapters.
The evolution of dorsal-ventral patterning mechanisms in insects.

PubMed

Lynch, Jeremy A; Roth, Siegfried

2011-01-15

The gene regulatory network (GRN) underpinning dorsal-ventral (DV) patterning of the Drosophila embryo is among the most thoroughly understood GRNs, making it an ideal system for comparative studies seeking to understand the evolution of development. With the emergence of widely applicable techniques for testing gene function, species with sequenced genomes, and multiple tractable species with diverse developmental modes, a phylogenetically broad and molecularly deep understanding of the evolution of DV axis formation in insects is feasible. Here, we review recent progress made in this field, compare our emerging molecular understanding to classical embryological experiments, and suggest future directions of inquiry.
Nasal dermoid sinus cysts: an unusual presentation, computed tomographic scan findings, and surgical results.

PubMed

Posnick, J C; Bortoluzzi, P; Armstrong, D C

1994-05-01

Midline nasal dermoid cysts are congenital lesions resulting from aberrant embryological development. Accurate diagnosis and effective treatment are essential to avoid craniofacial skeletal deformations, cyst rupture, and infection that could cause cutaneous, ocular, or intracranial complications. We report an unusual case of congenital midline nasal dermoid cysts in which an 18-month-old child presented to a hospital emergency department with periorbital cellulitis. It resulted from multiple midline nasal dermoid cysts involving the nasal, forehead, and both orbital regions but without intracranial extension. The patient was successfully managed with a craniofacial approach.
The Vienna consensus: report of an expert meeting on the development of ART laboratory performance indicators.

PubMed

2017-11-01

This proceedings report presents the outcomes from an international workshop supported by the European Society of Human Reproduction and Embryology (ESHRE) and Alpha Scientists in Reproductive Medicine, designed to establish consensus on definitions and recommended values for Indicators for the assisted reproductive technology (ART) laboratory. Minimum performance-level values ('competency') and aspirational ('benchmark') values were recommended for a total of 19 Indicators, including 12 Key Performance Indicators (KPIs), five Performance Indicators (PIs), and two Reference Indicators (RIs). Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Using Web-Based Tools for Teaching Embryology

EPA Science Inventory

Computers, imaging technologies, and the worldwide web have assumed an important role in augmenting traditional learning. Resources to disseminate multimedia information across platforms, and the emergence of communal knowledge environments, facilitate the visualization of diffi...
Predictive Models and Computational Embryology

EPA Science Inventory

EPA’s ‘virtual embryo’ project is building an integrative systems biology framework for predictive models of developmental toxicity. One schema involves a knowledge-driven adverse outcome pathway (AOP) framework utilizing information from public databases, standardized ontologies...
Greater Growth of Proximal Metatarsals in Bird Embryos and the Evolution of Hallux Position in the Grasping Foot.

PubMed

Botelho, João Francisco; Smith-Paredes, Daniel; Soto-Acuña, Sergio; Núñez-León, Daniel; Palma, Verónica; Vargas, Alexander O

2017-01-01

In early theropod dinosaurs-the ancestors of birds-the hallux (digit 1) had an elevated position within the foot and had lost the proximal portion of its metatarsal. It no longer articulated with the ankle, but was attached at about mid-length of metatarsal 2 (mt2). In adult birds, the hallux is articulated closer to the distal end of mt2 at ground level with the other digits. However, on chick embryonic day 7, its position is as in early theropods at half-length of mt2. The adult distal location is acquired during embryonic days 8-10. To assess how the adult phenotype is acquired, we produced fate maps of the metatarsals of day 6 chicken embryos injecting the lipophilic tracer DiI. The fates of these marks indicate a larger expansion of the metatarsals at their proximal end, which creates the illusory effect that d1 moves distally. This larger proximal expansion occurs concomitantly with growth and early differentiation of cartilage. Histological analysis of metatarsals shows that the domains of flattened and prehypertrophic chondrocytes are larger toward the proximal end. The results suggest that the distal position of the hallux in the avian foot evolved as a consequence of an embryological period of expansion of the metatarsus toward the proximal end. It also brings attention to the developmental mechanisms leading to differential growth between epiphyses and their evolutionary consequences. © 2016 Wiley Periodicals, Inc.
[The gastrulation in Cnidaria: A key to understanding phylogeny or the chaos of secondary modifications?].

PubMed

Kraus, Yu A; Markov, A V

2016-01-01

The data revealed by comparative embryology of the basal (diploblastic) metazoans is traditionally considered a valuable potential source of information on the origin and early evolution of the animal kingdom and its major clades. Special attention is paid to the fundamental morphogenetic process of gastrulation during which the cells of the early embryo differentiate into the germ layers and the primary body plan is formed. Comparative analysis of gastrulation in different cnidarian taxa reveals high level of intergroup, intragroup, and individual variation. With few exceptions, there is no robust correlation between the type of gastrulation and the taxon. Current data do not support the idea that morphogenetic processes underlying cnidarian gastrulation can be divided into several distinct types. Rather, there is a continuum of equifinal ontogenetic trajectories. In cnidarians, the mode of gastrulation apparently depends less on the macroevolutionary history of the species than on various evolutionary plastic features, such as the oocyte size, the amount of yolk, the number of cells at the blastula (or morula) stage, the presence of phototrophic symbionts, or the ecology of the larva. Thus, in cnidarians, morphogenetic basis of gastrulation contains only a very weak phylogenetic signal and can have only limited application in phylogenetic reconstructions. On the other hand, comparative studies of the ontogeny of the basal metazoans shed light on the general rules of the evolution of morphogenetic processes that is crucial for understanding the early history of the animal kingdom.
Stable isotope evidence for an amphibious phase in early proboscidean evolution

PubMed Central

Liu, Alexander G. S. C.; Seiffert, Erik R.; Simons, Elwyn L.

2008-01-01

The order Proboscidea includes extant elephants and their extinct relatives and is closely related to the aquatic sirenians (manatees and dugongs) and terrestrial hyracoids (hyraxes). Some analyses of embryological, morphological, and paleontological data suggest that proboscideans and sirenians shared an aquatic or semiaquatic common ancestor, but independent tests of this hypothesis have proven elusive. Here we test the hypothesis of an aquatic ancestry for advanced proboscideans by measuring δ18O in tooth enamel of two late Eocene proboscidean genera, Barytherium and Moeritherium, which are sister taxa of Oligocene-to-Recent proboscideans. The combination of low δ18O values and low δ18O standard deviations in Barytherium and Moeritherium matches the isotopic pattern seen in aquatic and semiaquatic mammals, and differs from that of terrestrial mammals. δ13C values of these early proboscideans suggest that both genera are likely to have consumed freshwater plants, although a component of C3 terrestrial vegetation cannot be ruled out. The simplest explanation for the combined evidence from isotopes, dental functional morphology, and depositional environments is that Barytherium and Moeritherium were at least semiaquatic and lived in freshwater swamp or riverine environments, where they grazed on freshwater vegetation. These results lend new support to the hypothesis that Oligocene-to-Recent proboscideans are derived from amphibious ancestors. PMID:18413605
Stable isotope evidence for an amphibious phase in early proboscidean evolution.

PubMed

Liu, Alexander G S C; Seiffert, Erik R; Simons, Elwyn L

2008-04-15

The order Proboscidea includes extant elephants and their extinct relatives and is closely related to the aquatic sirenians (manatees and dugongs) and terrestrial hyracoids (hyraxes). Some analyses of embryological, morphological, and paleontological data suggest that proboscideans and sirenians shared an aquatic or semiaquatic common ancestor, but independent tests of this hypothesis have proven elusive. Here we test the hypothesis of an aquatic ancestry for advanced proboscideans by measuring delta(18)O in tooth enamel of two late Eocene proboscidean genera, Barytherium and Moeritherium, which are sister taxa of Oligocene-to-Recent proboscideans. The combination of low delta(18)O values and low delta(18)O standard deviations in Barytherium and Moeritherium matches the isotopic pattern seen in aquatic and semiaquatic mammals, and differs from that of terrestrial mammals. delta(13)C values of these early proboscideans suggest that both genera are likely to have consumed freshwater plants, although a component of C(3) terrestrial vegetation cannot be ruled out. The simplest explanation for the combined evidence from isotopes, dental functional morphology, and depositional environments is that Barytherium and Moeritherium were at least semiaquatic and lived in freshwater swamp or riverine environments, where they grazed on freshwater vegetation. These results lend new support to the hypothesis that Oligocene-to-Recent proboscideans are derived from amphibious ancestors.
Craniofacial embryology and postnatal development of relevant parts of the upper respiratory system.

PubMed

Halewyck, S; Louryan, S; Van Der Veken, P; Gordts, F

2012-01-01

To compare historical and current knowledge relating to the development of the paranasal sinuses, the nose and face, the Eustachian tube and temporal bones, particularly with respect to chronic inflammation during childhood. Traditional literature data, mainly emanating from text books, were supplemented with information based on a non-structured PubMed search covering the last two decades. Historical knowledge has most often been confirmed, sometimes supplemented and only rarely challenged by present-day studies. Recent studies focus mainly on the clinical application of modern imaging techniques. Interest in the development of relevant parts of the upper respiratory system remains as lively as ever. Imaging techniques with low or absent radiation exposure may give rise to a novel field of research, especially with respect to paediatric rhinosinusitis.
Pitt-Hopkins Syndrome: A Review of Current Literature, Clinical Approach, and 23-Patient Case Series.

PubMed

Goodspeed, Kimberly; Newsom, Cassandra; Morris, Mary Ann; Powell, Craig; Evans, Patricia; Golla, Sailaja

2018-03-01

Pitt-Hopkins syndrome (PTHS) is a rare, genetic disorder caused by a molecular variant of TCF4 which is involved in embryologic neuronal differentiation. PTHS is characterized by syndromic facies, psychomotor delay, and intellectual disability. Other associated features include early-onset myopia, seizures, constipation, and hyperventilation-apneic spells. Many also meet criteria for autism spectrum disorder. Here the authors present a series of 23 PTHS patients with molecularly confirmed TCF4 variants and describe 3 unique individuals. The first carries a small deletion but does not exhibit the typical facial features nor the typical pattern of developmental delay. The second exhibits typical facial features, but has attained more advanced motor and verbal skills than other reported cases to date. The third displays typical features of PTHS, however inherited a large chromosomal duplication involving TCF4 from his unaffected father with somatic mosaicism. To the authors' knowledge, this is the first chromosomal duplication case reported to date.
Teleomechanism redux? Functional physiology and hybrid models of life in early modern natural philosophy.

PubMed

Wolfe, Charles T

2014-01-01

The distinction between 'mechanical' and 'teleological' has been familiar since Kant; between a fully mechanistic, quantitative science of Nature and a teleological, qualitative approach to living beings, namely 'organisms' understood as purposive or at least functional entities. The beauty of this distinction is that it apparently makes intuitive sense and maps onto historico-conceptual constellations in the life sciences, regarding the status of the body versus that of the machine. I argue that the mechanism-teleology distinction is imprecise and flawed using examples including the 'functional' features present even in Cartesian physiology, the Oxford Physiologists' work on circulation and respiration, the fact that the model of the 'body-machine' is not a mechanistic reduction of organismic properties to basic physical properties but is focused on the uniqueness of organic life; and the concept of 'animal economy' in vitalist medicine, which I present as a 'teleomechanistic' concept of organism (borrowing a term of Lenoir's which he applied to nineteenth-century embryology)--neither mechanical nor teleological.
The road to embryologically based dose-response models.

PubMed Central

Kavlock, R J; Setzer, R W

1996-01-01

The goal of researchers working in the area of developmental toxicology is to prevent adverse reproductive outcomes (early pregnancy loss, birth defects, reduced birth weight, and altered functional development) in humans due to exposures to environmental contaminants, therapeutic drugs, and other factors. To best achieve that goal, it is important that relevant information be gathered and assimilated in the risk assessment process. One of the major challenges of improved risk assessment is to better use all pertinent biological and mechanistic information. This may be done qualitatively (e.g., demonstrating that the experimental model is not appropriate for extrapolation purposes); semiquantitatively (using information to reduce the degree of uncertainty present under default extrapolation procedures), or quantitatively (formally describing the relationships between exposure and adverse outcome in mathematical forms, including components that directly reflect individual steps in the overall progression of toxicity). In this paper we review the recent advances in the risk assessment process for developmental toxicants and hypothesize on future directions that may revolutionize our thinking in this area. The road to these changes sometimes appears to be a well-mapped course on a relatively smooth surface; at other times the path is bumpy and obscure, while at still other times it is only a wish in the eye of the engineer to cross an uncharted and rugged environment. Images Figure 11. A Figure 11. B PMID:8722115
Human embryonic stem cells express a unique set of microRNAs.

PubMed

Suh, Mi-Ra; Lee, Yoontae; Kim, Jung Yeon; Kim, Soo-Kyoung; Moon, Sung-Hwan; Lee, Ji Yeon; Cha, Kwang-Yul; Chung, Hyung Min; Yoon, Hyun Soo; Moon, Shin Yong; Kim, V Narry; Kim, Kye-Seong

2004-06-15

Human embryonic stem (hES) cells are pluripotent cell lines established from the explanted inner cell mass of human blastocysts. Despite their importance for human embryology and regenerative medicine, studies on hES cells, unlike those on mouse ES (mES) cells, have been hampered by difficulties in culture and by scant knowledge concerning the regulatory mechanism. Recent evidence from plants and animals indicates small RNAs of approximately 22 nucleotides (nt), collectively named microRNAs, play important roles in developmental regulation. Here we describe 36 miRNAs (from 32 stem-loops) identified by cDNA cloning in hES cells. Importantly, most of the newly cloned miRNAs are specifically expressed in hES cells and downregulated during development into embryoid bodies (EBs), while miRNAs previously reported from other human cell types are poorly expressed in hES cells. We further show that some of the ES-specific miRNA genes are highly related to each other, organized as clusters, and transcribed as polycistronic primary transcripts. These miRNA gene families have murine homologues that have similar genomic organizations and expression patterns, suggesting that they may operate key regulatory networks conserved in mammalian pluripotent stem cells. The newly identified hES-specific miRNAs may also serve as molecular markers for the early embryonic stage and for undifferentiated hES cells.
[Obstructed hemivagina and ipsilateral renal anomaly: unusual cause of piocolpos. Report a case and review of literature ].

PubMed

Cortés-Contreras, Diana Karen; Juárez-Cruz, Patricio Manuel; Vázquez-Flores, José; Vázquez-Flores, Al David

2014-10-01

OHVIRA (Obstructed hemivagina and ipsilateral renal anomaly) by acronym and abbreviations in English or Herlyn Werner Wunderlich syndrome is a rare congenital malformation caused by an alteration in the Mullerian ducts and Wolffian Ducts. Which is characterized by a triad: uterus didelphys, obstructed and ipsilateral renal agenesis hemivagina still uncertain etiology. Patients are usually asymptomatic until menarche where the most common clinical presentation is pelvic pain, followed by a vaginal or abdominal mass, normal menstrual periods, infertility, and vaginal discharge rarely appears. The case of a female patient of 15 years, nubile with chronic fetid vaginal discharge, initially diagnosed and treated as pelvic inflammatory disease occurs, however because it is an exceptional condition with the background of the patient, by complementary studies were conducted where pelvic ultrasound revealed pyocolpos and absence of left kidney, uterus didelphys, blind hemivagina by other imaging studies, where we could integrate Herlyn-Werner-Wunderlich syndrome. In conclusion, abnormalities in the development of the Miillerian ducts are difficult to diagnose early, so you must have the embryological knowledge, conduct thorough clinical assessment and detailed picture in whom the coridition is suspected to identify malformations coexisting urinary tract and vaginal defects with the importance of preserving reproductive success through appropriate planning of surgical approach, given that the fertility rate in these patients is comparable to the average.
EMBRYOLOGY OF AUTISM. (R824758)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...
Publications of the space biology program for 1975-1977: A special bibliography

NASA Technical Reports Server (NTRS)

Felt, J. C. (Compiler); Halstead, T. W. (Compiler)

1978-01-01

Documents cited represent research encompassing several disciplines of space biology: botany and plant pathology, physiology and biophysics, agricultural and environmental sciences, anatomy and embryology, cellular and comparative biology, horticulture and aerospace biology.
Could Revision of the Embryology Influence Our Cesarean Delivery Technique: Towards an Optimized Cesarean Delivery for Universal Use

PubMed Central

Stark, Michael; Mynbaev, Ospan; Vassilevski, Yuri; Rozenberg, Patrick

2016-01-01

Until today, there is no standardized Cesarean Section method and many variations exist. The main variations concern the type of abdominal incision, usage of abdominal packs, suturing the uterus in one or two layers, and suturing the peritoneal layers or leaving them open. One of the questions is the optimal location of opening the uterus. Recently, omission of the bladder flap was recommended. The anatomy and histology as results from the embryological knowledge might help to solve this question. The working thesis is that the higher the incision is done, the more damage to muscle tissue can take place contrary to incision in the lower segment, where fibrous tissue prevails. In this perspective, a call for participation in a two-armed prospective study is included, which could result in an optimal, evidence-based Cesarean Section for universal use. PMID:28078171

Parapharyngeal cyst: considerations on embryology, clinical evaluation, and surgical management.

PubMed

Dallan, Iacopo; Seccia, Veronica; Bruschini, Luca; Ciancia, Eugenio; Franceschini, Stefano Sellari

2008-11-01

Branchial cleft anomalies represent a common cause of cervical mass in adults. Describing a case report, we reviewed embryology, clinical elements, and treatment options for parapharyngeal congenital cysts. A case of a parapharyngeal cyst mimicking a tonsillar abscess is presented. A second branchial cleft cyst was hypothesized on a clinical and radiologic basis and then confirmed by histologic data. Magnetic resonance imaging provided fundamental information for the study of the parapharyngeal mass and its relationship with surrounding structures. In literature, surgical excision is the recommended therapy. We removed the cyst through a transcervical approach, with no complications or recurrence after 3 years. In our opinion, cervicotomy should be considered the gold standard approach, even for lesions not palpable in the cervical area. When dealing with a parapharyngeal cyst, second branchial cleft anomalies should be considered. Our experience confirms that cervicotomy is a safe approach to parapharyngeal congenital lesions.
Toxicological and chemical assessment of ordnance compounds in marine sediments and porewaters

USGS Publications Warehouse

Nipper, M.; Carr, R.S.; Biedenbach, J.M.; Hooten, R.L.; Miller, K.

2002-01-01

Toxicological and chemical studies were performed with a silty and a sandy marine sediment spiked with 2,6-dinitrotoluene (2,6-DNT), 2,4,6-trinitrophenylmethylnitramine (tetryl), or 2,4,6-trinitrophenol (picric acid). Whole sediment toxicity was analyzed by the 10-day survival test with the amphipod Ampelisca abdita, and porewater toxicity tests assessed macro-algae (Ulva fasciata) zoospore germination and germling growth, sea urchin (Arbacia punctulata) embryological development, and polychaete (Dinophilus gyrociliatus) survival and reproduction. Whole sediments spiked with 2,6-DNT were not toxic to amphipods. The fine-grained sediment spiked with tetryl was also not acutely toxic. The tetryl and picric acid LC50 values in the sandy sediment were 3.24 and 144 mg/kg dry weight, respectively. The fine-grained sediment spiked with picric acid generated a U-shaped concentration-response curve in the amphipod test, with increased survival both in the lowest and highest concentration. Grain-size distribution and organic carbon content strongly influenced the behavior of ordnance compounds in spiked sediments. Very low concentrations were measured in some of the treatments and irreversible binding and biodegradation are suggested as the processes responsible for the low measurements. Porewater toxicity varied with its sedimentary origin and with ordnance compound. The sea urchin embryological development test tended to be the least sensitive. Tetryl was the most toxic chemical in all porewater tests, and picric acid the least toxic. Samples spiked with 2,6-DNT contained a degradation product identified as 2-methyl-3-nitroaniline (also known as 2-amino-6-nitrotoluene), and unidentified peaks, possibly degradation products, were also seen in some of the picric acid- and tetryl-spiked samples. Degradation products may have played a role in observed toxicity. ?? 2002 Elsevier Science Ltd. All rights reserved.
Adult Rat Bones Maintain Distinct Regionalized Expression of Markers Associated with Their Development

PubMed Central

Rawlinson, Simon C. F.; McKay, Ian J.; Ghuman, Mandeep; Wellmann, Claudia; Ryan, Paul; Prajaneh, Saengsome; Zaman, Gul; Hughes, Francis J.; Kingsmill, Virginia J.

2009-01-01

The incidence of limb bone fracture and subsequent morbidity and mortality due to excessive bone loss is increasing in the progressively ageing populations of both men and women. In contrast to bone loss in the weight-bearing limb, bone mass in the protective skull vault is maintained. One explanation for this could be anatomically diverse bone matrix characteristics generated by heterogeneous osteoblast populations. We have tested the hypothesis that adult bones demonstrate site-specific characteristics, and report differences at the organ, cell and transcriptome levels. Limb bones contain greater amounts of polysulphated glycosaminoglycan stained with Alcian Blue and have significantly higher osteocyte densities than skull bone. Site-specific patterns persist in cultured adult bone-derived cells both phenotypically (proliferation rate, response to estrogen and cell volumes), and at the level of specific gene expression (collagen triple helix repeat containing 1, reelin and ras-like and estrogen-regulated growth inhibitor). Based on genome-wide mRNA expression and cluster analysis, we demonstrate that bones and cultured adult bone-derived cells segregate according to site of derivation. We also find the differential expression of genes associated with embryological development (Skull: Zic, Dlx, Irx, Twist1 and Cart1; Limb: Hox, Shox2, and Tbx genes) in both adult bones and isolated adult bone-derived cells. Together, these site-specific differences support the view that, analogous to different muscle types (cardiac, smooth and skeletal), skull and limb bones represent separate classes of bone. We assign these differences, not to mode of primary ossification, but to the embryological cell lineage; the basis and implications of this division are discussed. PMID:20027296
Clinical practice guidelines for the care of girls and women with Turner syndrome: proceedings from the 2016 Cincinnati International Turner Syndrome Meeting.

PubMed

Gravholt, Claus H; Andersen, Niels H; Conway, Gerard S; Dekkers, Olaf M; Geffner, Mitchell E; Klein, Karen O; Lin, Angela E; Mauras, Nelly; Quigley, Charmian A; Rubin, Karen; Sandberg, David E; Sas, Theo C J; Silberbach, Michael; Söderström-Anttila, Viveca; Stochholm, Kirstine; van Alfen-van derVelden, Janielle A; Woelfle, Joachim; Backeljauw, Philippe F

2017-09-01

Turner syndrome affects 25-50 per 100,000 females and can involve multiple organs through all stages of life, necessitating multidisciplinary approach to care. Previous guidelines have highlighted this, but numerous important advances have been noted recently. These advances cover all specialty fields involved in the care of girls and women with TS. This paper is based on an international effort that started with exploratory meetings in 2014 in both Europe and the USA, and culminated with a Consensus Meeting held in Cincinnati, Ohio, USA in July 2016. Prior to this meeting, five groups each addressed important areas in TS care: 1) diagnostic and genetic issues, 2) growth and development during childhood and adolescence, 3) congenital and acquired cardiovascular disease, 4) transition and adult care, and 5) other comorbidities and neurocognitive issues. These groups produced proposals for the present guidelines. Additionally, four pertinent questions were submitted for formal GRADE (Grading of Recommendations, Assessment, Development and Evaluation) evaluation with a separate systematic review of the literature. These four questions related to the efficacy and most optimal treatment of short stature, infertility, hypertension, and hormonal replacement therapy. The guidelines project was initiated by the European Society for Endocrinology and the Pediatric Endocrine Society, in collaboration with The European Society for Pediatric Endocrinology, The Endocrine Society, European Society of Human Reproduction and Embryology, The American Heart Association, The Society for Endocrinology, and the European Society of Cardiology. The guideline has been formally endorsed by the European Society for Endocrinology, the Pediatric Endocrine Society, the European Society for Pediatric Endocrinology, the European Society of Human Reproduction and Embryology and the Endocrine Society. Advocacy groups appointed representatives who participated in pre-meeting discussions and in the consensus meeting. © 2017 European Society of Endocrinology.
Anatomical variations in the origins of the celiac axis and the superior mesenteric artery: MDCT angiographic findings and their probable embryological mechanisms.

PubMed

Wang, Yi; Cheng, Cheng; Wang, Lu; Li, Ran; Chen, Jin-hua; Gong, Shui-gen

2014-08-01

To identify the spectrum and prevalence of anatomical variations in the origin of the celiac axis (CA), the superior mesenteric artery (SMA) and their major branches by using multidetector computed tomographic (MDCT) angiography. A retrospective evaluation was carried out on 1,500 abdominal MDCT angiography images. The aortic origins of the CA, the SMA and their major branch patterns were investigated. Normal aortic origins of CA and SMA were noted in 1,347 (89.8%) patients. Seven types of CA and SMA origin variants were identified in 153 (10.2%) patients. The three most common variations were hepatomesenteric trunk (67 patients, 4.47%), celiomesenteric trunk (CMT) (51 patients, 3.4%) and splenomesenteric trunk (18 patients, 1.2%). An evaluation of CMT was classified as long (34 patients, 66.7%) or short (17 patients, 33.3%) subtypes, compared with the length of the common trunk. Further CMT classification was based on the origin of the left gastric artery: subtype I, 26 patients (53.1%); subtype II, 5 patients (10.2%); subtype III, 15 patients (30.6%); subtype IV, 3 patients (6.1%). Dislocation interruption, incomplete interruption and persistence of the longitudinal anastomosis could be the embryological mechanisms of the variant origins of the CA, the SMA and their major branches. • Aortic origins of CA, SMA and their major branches were investigated. • Celiomesenteric trunk includes several different subtypes and configurations. • Probable embryological mechanisms of origin variants in these observed arteries were discussed. • Origin variants in these observed arteries have wide-ranging health implications.
Nonlinear dimension reduction and clustering by Minimum Curvilinearity unfold neuropathic pain and tissue embryological classes.

PubMed

Cannistraci, Carlo Vittorio; Ravasi, Timothy; Montevecchi, Franco Maria; Ideker, Trey; Alessio, Massimo

2010-09-15

Nonlinear small datasets, which are characterized by low numbers of samples and very high numbers of measures, occur frequently in computational biology, and pose problems in their investigation. Unsupervised hybrid-two-phase (H2P) procedures-specifically dimension reduction (DR), coupled with clustering-provide valuable assistance, not only for unsupervised data classification, but also for visualization of the patterns hidden in high-dimensional feature space. 'Minimum Curvilinearity' (MC) is a principle that-for small datasets-suggests the approximation of curvilinear sample distances in the feature space by pair-wise distances over their minimum spanning tree (MST), and thus avoids the introduction of any tuning parameter. MC is used to design two novel forms of nonlinear machine learning (NML): Minimum Curvilinear embedding (MCE) for DR, and Minimum Curvilinear affinity propagation (MCAP) for clustering. Compared with several other unsupervised and supervised algorithms, MCE and MCAP, whether individually or combined in H2P, overcome the limits of classical approaches. High performance was attained in the visualization and classification of: (i) pain patients (proteomic measurements) in peripheral neuropathy; (ii) human organ tissues (genomic transcription factor measurements) on the basis of their embryological origin. MC provides a valuable framework to estimate nonlinear distances in small datasets. Its extension to large datasets is prefigured for novel NMLs. Classification of neuropathic pain by proteomic profiles offers new insights for future molecular and systems biology characterization of pain. Improvements in tissue embryological classification refine results obtained in an earlier study, and suggest a possible reinterpretation of skin attribution as mesodermal. https://sites.google.com/site/carlovittoriocannistraci/home.
Embryological Research.

ERIC Educational Resources Information Center

Oppenheimer, Steven B.

1989-01-01

To integrate a research/discovery component into one course, an experiment using the sea urchin embryo system is introduced because the teacher manages only one organism and students provide the variables. The materials, handling methods, and experimental methods of the experiment are described. (YP)
The head problem. The organizational significance of segmentation in head development.

PubMed

Horder, Tim J; Presley, Robert; Slípka, Jaroslav

2010-01-01

This review argues for the segmental basis of chordate head organization which, like somite-based segmental organization in the trunk, takes its origin from early mesodermal development. The review builds on, and brings up to date, Goodrich's well-known scheme of head organization. It surveys recent data in support of this scheme and shows how evidence and arguments supposedly in conflict with it can be accommodated. Many of the arguments revolve around matters of methodology; the limitations of older LM, SEM (on which the concept of "somitomeres" is based) and recent molecular evidence (which has sometimes been seen as allocating the central role in head organization to the CNS and the neural crest) are highlighted and shown to explain a number of claims contrary to Goodrich's. We provide (in Part 2) a new, comparative survey of the best available evidence most directly relevant to the Goodrich Bauplan, with a special emphasis on stem chordates. The postotic region has commonly been seen as segmentally organized: the critical issues concern the preotic region. There are many reasons why Goodrich's three preotic segments may become specialized during evolution and why the underlying initial segmental organization may be overridden in later stages during embryonic development; we refer to a number of these. We conclude that the preotic segmental Bauplan is remarkably conserved and most explicitly demonstrated among stem forms, but we also suggest that the concept of the prechordal plate requires careful reexamination. Central to our overall analysis is the importance of the epigenetic nature of embryogenesis; its implications are made clear. Finally we speculate on evolutionary implications for the origin of the head and its specialized features. The review is intended to serve as a resource giving access to references to a wealth of now neglected, older data on anamniote embryology.
Human female meiosis revised: new insights into the mechanisms of chromosome segregation and aneuploidies from advanced genomics and time-lapse imaging.

PubMed

Capalbo, Antonio; Hoffmann, Eva R; Cimadomo, Danilo; Ubaldi, Filippo Maria; Rienzi, Laura

2017-11-01

The unbalanced transmission of chromosomes in human gametes and early preimplantation embryos causes aneuploidy, which is a major cause of infertility and pregnancy failure. A baseline of 20% of human oocytes are estimated to be aneuploid and this increases exponentially from 30 to 35 years, reaching on average 80% by 42 years. As a result, reproductive senescence in human females is predominantly determined by the accelerated decline in genetic quality of oocytes from 30 years of age. Understanding mechanisms of chromosome segregation and aneuploidies in the female germline is a crucial step towards the development of new diagnostic approaches and, possibly, for the development of therapeutic targets and molecules. Here, we have reviewed emerging mechanisms that may drive human aneuploidy, in particular the maternal age effect. We conducted a systematic search in PubMed Central of the primary literature from 1990 through 2016 following the PRISMA guidelines, using MeSH terms related to human aneuploidy. For model organism research, we conducted a literature review based on references in human oocytes manuscripts and general reviews related to chromosome segregation in meiosis and mitosis. Advances in genomic and imaging technologies are allowing unprecedented insight into chromosome segregation in human oocytes. This includes the identification of a novel chromosome segregation error, termed reverse segregation, as well as sister kinetochore configurations that were not predicted based on murine models. Elucidation of mechanisms that result in errors in chromosome segregation in meiosis may lead to therapeutic developments that could improve reproductive outcomes by reducing aneuploidy. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com
Paramagnetic Beads and Magnetically Mediated Strain Enhance Cardiomyogenesis in Mouse Embryoid Bodies

PubMed Central

Geuss, Laura R.; Wu, Douglas C.; Ramamoorthy, Divya; Alford, Corinne D.; Suggs, Laura J.

2014-01-01

Mechanical forces play an important role in proper embryologic development, and similarly such forces can directly impact pluripotency and differentiation of mouse embryonic stem cells (mESC) in vitro. In addition, manipulation of the embryoid body (EB) microenvironment, such as by incorporation of microspheres or microparticles, can similarly influence fate determination. In this study, we developed a mechanical stimulation regimen using permanent neodymium magnets to magnetically attract cells within an EB. Arginine-Glycine-Aspartic Acid (RGD)-conjugated paramagnetic beads were incorporated into the interior of the EBs during aggregation, allowing us to exert force on individual cells using short-term magnetization. EBs were stimulated for one hour at different magnetic field strengths, subsequently exerting a range of force intensity on the cells at different stages of early EB development. Our results demonstrated that following exposure to a 0.2 Tesla magnetic field, ESCs respond to magnetically mediated strain by activating Protein Kinase A (PKA) and increasing phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2) expression. The timing of stimulation can also be tailored to guide ESC differentiation: the combination of bone morphogenetic protein 4 (BMP4) supplementation with one hour of magnetic attraction on Day 3 enhances cardiomyogenesis by increasing contractile activity and the percentage of sarcomeric α-actin-expressing cells compared to control samples with BMP4 alone. Interestingly, we also observed that the beads alone had some impact on differentiation by increasingly slightly, albeit not significantly, the percentage of cardiomyocytes. Together these results suggest that magnetically mediated strain can be used to enhance the percentage of mouse ESC-derived cardiomyocytes over current differentiation protocols. PMID:25501004
The C.E.B.A. Mini Module on the STS-107 Mission: Data of Ground Experiments and Preliminary Results of the third Spaceflight of an Artificial Aquatic Ecosystem

NASA Astrophysics Data System (ADS)

Bluem, V.; Paris, F.; Bungart, S.

The C.E.B.A.S MINI MODULE is the miniaturized version of an artificial aquatic ecosystem consisting of four subcomponents: a ZOOLOGICAL COMPONENT (aquarium for animals), a BOTANICAL COMPONENT (higher water plant bioreactor), a MICROBIAL COMPONENT (bacteria filter) and an ELECTRONICAL COMPONENT (data acquisition, control unit). It has a total volume of 8.6 liters and contains the ovoviviparous teleost Xiphophorus helleri (swordtail), larvae of the ovuliparous cichlid fish Oreochromis mossambicus, the pulmonate water snail Biomphalaria glabrata, the rootless (non-graivitropic) higher water plant Ceratophyllum demersum (hornweed) and special strains of ammonia oxidizing bacteria. This device was already flown twice successfully in space with the space shuttle missions STS- 89 and STS-90 (NEUROLAB) in 1998. It will fly a third time with the STS-107-mission the launch of which has been repeatedly shifted December 222, April 2001, October 2001) and is now finally scheduled for June 2002. The main focus of scientific interest in the past missions were system performance, reproductive biology (reproductive function of adult females including endocrine system, fertilization, gonadal development in juveniles), vestibular and immunological research in X. helleri, embryology and shell formation in B. glabrata, general morphology and physiology of C. demersum and groth rates of the bacteria. The standard load of the system were 4 adult and 200 neonate X. helleri, 30 adult B. glabrata and 30 g of C. demersum. The evaluation of these experiments showed that all reproductive functions and the immune system of the fishes snails remained undisturbed in space, that the snails developed normally and exhibited no disturbance of shell formation and that the plants showed growth and photosynthesis rates comparable to those on Earth. So, as a logical continuation, the main topics for the STS-107 mission are the remaining important questions in X. helleri biology: puberty, male sexual behavior and function, embryology and skeleton formation. According to the scientific questions the biological load has to be modified to meet the requirements and to ensure the undisturbed function of the C.E.B.A.S. MINI MODULE for a possible mission duration of more than 20 days. So, 3 freshly pregnant females and one mature male will be inserted into the "Large Animal Compartment" of the ZOOLOGICAL COMPONENT and 12 to 14 half-grown fishes of both sexes just before sexual maturation into the "Small Animal Compartment". Fifty larvae of the Cichlid fish Oreochromis mossambicus will be placed into a special perfused container within the "Large Animal Compartment" which serve for vestibular research. Although no further investigations will be performed in B. glabrata about 30 adult snails will be implemented into the system functioning as "biological vacuum cleaners". The starting plant biomass of C. demersum is reduced to 20 to 25 g to minimize self- shadowing of the plants in the last days of the mission. This setup was already successfully tested in a "Ship and Shoot Test" lasting 26 days including the transportation of the C.E.B.A.S. MINI MODULE from Germany to Kennedy Space Center (KSC) and back thus demonstrating the high biological stability of the system. The "Ship and Shot Scenario" was a test only and will not be used for the space flight by reasons of possible transportation delays when using planes of commercial airlines. Therefore, for spaceflight the C.E.B.A.S. MINI MODULE will be filled with biological material and recovered after the mission at KSC. Preliminary ground investigations ensure a broad basis of comparison for control purposes. All relevant parameters of X. helleri puberty (gonopodial and sword growth, gonadal status, changes in brain gonadotropin releasing hormone (GnRH) centers and in hypophyseal gonadotropin (GtH) sources), embryology (total embryonic development) and skeleton formation (main focus on axial skeleton and fins) were collected and evaluated. It turned out that in the male sex the gonopodial development is an excellent parameter in combination with defined morphological changes in the testis as the onset of meiosis. In females the formation of oocytes and the start of vitellogenesis allow a safe definition of puberty. In both sexes the sexual maturation is accompanied my marked morphological changes of the GnRH system and the GtH cells in the pituitary gland. The male sexual behavior was recorded in a comprehensive quantitative ethogram so that possible alterations can be easily detected. In the field of embryology all possible "marker organs" were selected which enable a direct correlation of developmental stage and duration of gestation. The most important of those are eye and skin pigmentation, eye development, circulatory system, pericardial sac and otoliths. The axial skeleton development has been found to be extremely suitable to study the biomineralization process in chronology which will be used to detect possible alterations during the time of space flight. The lecture will present the latest results of ground experiments in embryology and skeleton research as well as the first results of the STS-107 spaceflifht including system performance data. Moreover, the possible further development of the C.E.B.A.S. and the utizitation of its basic biotechnology for the construction of aquatic modules für bioregenerative life support systems will be discussed.
Generation of a Three-Dimensional Kidney Structure from Pluripotent Stem Cells.

PubMed

Yoshimura, Yasuhiro; Taguchi, Atsuhiro; Nishinakamura, Ryuichi

2017-01-01

The kidney is a vital organ that has an important role in the maintenance of homeostasis by fluid volume regulation and waste product excretion. This role cannot be performed without the three-dimensional (3D) structure of the kidney. Therefore, it is important to generate the 3D structure of the kidney when inducing functional kidney tissue or the whole organ from pluripotent stem cells. In this chapter, we describe the detailed methods to induce kidney progenitor cells from pluripotent stem cells, which are based on embryological development. We also provide a method to generate 3D kidney tissue with vascularized glomeruli upon transplantation.
Surgical implications of portal venous system malformation

PubMed Central

Marks, Charles

1974-01-01

The significance of congenital abnormalities in predisposing to portal hypertension and variceal haemorrhage needs to be remembered when these effects manifest in childhood, as portal venography will permit elucidation of the complicated congenital developmental abnormalities underlying the pathological condition and permit rational surgical amelioration. In the presence of portal hypertension the development of a collateral venous circulation may be represented by a hepatopetal or hepatofugal circulatory pattern and will closely parallel the developmental areas where portal and systemic venous circulations meet, being representative of the embryological anastomosis between the vitelloumbilical system and the posterior cardinal system of veins. ImagesFig. 3Fig. 5Fig. 6 PMID:4614690
TIPS treatment in a patient with severe lower gastrointestinal bleeding with a misdiagnosis of cirrhotic portal hypertension.

PubMed

Laborda, Alicia; Guirola, José Andrés; Medrano, Joaquín; Simón, Miguel Ángel; Ioakeim, Ignatios; de-Gregorio, Miguel Ángel

2015-12-01

Abernethy malformation is a rare abnormal embryological development of splanchnic venous system characterised by the presence of a congenital extrahepatic portosystemic shunt. We present a rare case of an adult male patient that was admitted with severe lower gastrointestinal bleeding, requiring multiple blood transfusions. The patient's medical history and the laboratory tests performed led to the misdiagnosis of a congenital Abernethy malformation. We present a rare case, discussing the reasons for the misdiagnosis and we conclude that management of clinical data and imaging are highly important to discard these types of congenital malformations that can mimic a portal hypertension condition.
Multi-detector thoracic CT findings in cerebro-costo-mandibular syndrome: rib gaps and failure of costo-vertebral separation.

PubMed

Watson, Tom Anthony; Arthurs, Owen John; Muthialu, Nagarajan; Calder, Alistair Duncan

2014-02-01

Cerebro-costo-mandibular syndrome (CCMS) describes a triad of mandibular hypoplasia, brain dysfunction and posterior rib defects ("rib gaps"). We present the CT imaging for a 2-year-old girl with CCMS that highlights the rib gap defects and shows absent transverse processes with abnormal fusion of the ribs directly to the vertebral bodies. We argue that this is likely to relate to abnormal lateral sclerotome development in embryology, with the failure of normal costo-vertebral junctions compounding impaired thoracic function. The case also highlights the use of CT for specific indications in skeletal dysplasia.
Congenital Median Upper Lip Fistula

PubMed Central

al Aithan, Bandar

2012-01-01

Congenital median upper lip fistula (MULF) is an extremely rare condition resulting from abnormal fusion of embryologic structures. We present a new case of congenital medial upper lip fistula located in the midline of the philtrum of a 6 year old girl. PMID:22953305
Computational Embryology and Predictive Toxicology of Cleft Palate

EPA Science Inventory

Capacity to model and simulate key events in developmental toxicity using computational systems biology and biological knowledge steps closer to hazard identification across the vast landscape of untested environmental chemicals. In this context, we chose cleft palate as a model ...
Clinical radiology of the small intestine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herlinger, H.; Maglinte, D.

1989-01-01

This book discussed embryology, anatomy, physiology, and immunology of the small intestine. Radiographic procedures in the small intestine especially enterolysis are presented. Focus is on the role of other types of imaging techniques including sonography, computed tomography, radionuclide imaging, angiography, biopsy, and enteroscopy.
20180129 - Computational Embryology: Translational Tools for Modeling in vitro Data (Toxicology Forum)

EPA Science Inventory

Integrative models are needed to "decode the toxicological blueprint of active substances that interact with living systems" (Systems toxicology). Computational biology is uniquely positioned to capture this connectivity and help shift decision-making to mechanistic pre...
[Parental genome imprinting].

PubMed

Babinet, C

1993-01-01

Genetical as well as experimental embryology methods have permitted, in recent years, to uncover a very important feature of mammalian embryonic development: it has been shown that female and male genomic complements are differentially imprinted in such a way that contribution of both a maternally and a paternally derived genome are absolutely necessary for the embryo to complete its normal development. Differential genomic imprinting seems therefore to impose some new and essential kind of information to the one already contained in the genomic sequences. The differential imprinting should be imposed on the genetic material during gametogenesis and persist throughout somatic development after fertilization. It should then be erased in the germ cell line and be established again in sperm and egg genomes. The recent discovery of several mouse genes which are imprinted should permit to address the question of the molecular mechanisms of imprinting.

Biological Concerns on the Selection of Animal Models for Teratogenic Testing.

PubMed

Alves-Pimenta, Sofia; Colaço, Bruno; Oliveira, Paula A; Venâncio, Carlos

2018-01-01

During pregnancy fetus can be exposed to a variety of chemicals which may induce abortion and malformations. Due to the amounts of new substances coming into the market every year, a high demand for a rapid, reliable, and cost-effective method to detect potential toxicity is necessary. Different species have been used as animal models for teratogen screening, most of them sharing similar development processes with humans. However, the application of embryology knowledge to teratology is hampered by the complexity of the reproduction processes.The present chapter outlines the essential development periods in different models, and highlights the similarities and differences between species, advantages and disadvantages of each group, and specific sensitivities for teratogenic tests. These models can be organized into the following categories: (1) invertebrate species such Caenorhabditis elegans and Drosophila melanogaster, which have become ideal for screening simple mechanisms in the early periods of reproductive cycle, allowing for rapid results and minor ethical concerns; (2) vertebrate nonmammalian species such Xenopus laevis and Danio rerio, important models to assess teratogenic potential in later development with fewer ethical requirements; and (3) the mammalian species Mus musculus, Rattus norvegicus, and Oryctolagus cuniculus, phylogenetically more close to humans, essential to assess complex specialized processes, that occur later in development.Rules for development toxicology tests require the use of mammalian species. However, ethical concerns and costs limit their use in large-scale screening. By contrast, invertebrate and vertebrate nonmammalian species are increasing as alternative animal models, as these organisms combine less ethical requirements, low costs and culture conditions compatible with large-scale screening. In contrast to the in vitro techniques, their main advantage is to allow for high-throughput screening in a whole-animal context, not dependent on the prior identification of a target. In this chapter, the biological development of the animals most used in teratogenic tests is adressed with the aims of maximizing human translation, reducing the number of animals used, and the time to market for new drugs.
Development and Flight of the NASA-Ames Research Center Payload on Spacelab-J

NASA Technical Reports Server (NTRS)

Schmidt, Gregory K.; Ball, Sally M.; Stolarik, Thomas M.; Eodice, Michael T.

1993-01-01

Spacelab-J was an international Spacelab mission with numerous innovative Japanese and American materials and life science experiments. Two of the Spacelab-J experiments were designed over a period of more than a decade by a team from NASA-Ames Research Center. The Frog Embryology Experiment investigated and is helping to resolve a century-long quandary on the effects of gravity on amphibian development. The Autogenic Feedback Training Experiment, flown on Spacelab-J as part of a multi-mission investigation, studied the effects of Autogenic Feedback Therapy on limiting the effects of Space Motion Sickness on astronauts. Both experiments employed the use of a wide variety of specially designed hardware to achieve the experiment objectives. This paper reviews the development of both experiments, from the initial announcement of opportunity in 1978, through selection on Spacelab-J and subsequent hardware and science procedures development, culminating in the highly successful Spacelab-J flight in September 1992.
Studying the effects of microgravity on lower vertebrate development and behavior

NASA Technical Reports Server (NTRS)

Wassersug, Richard J.; Pronych, Scott; Souza, Kenneth A.

1991-01-01

Lower vertebrates have been used in space research for at least 3 decades, and have a number of advantages such as the ability to be maintained safely in space conditions, high development rates, easy observability, and small size. Several major investigations with lower vertebrates are in the flight queue in various countries, and some of this research with amphibians that has Canadian Space Agency sponsorship is reviewed. In connection with NASA's frog embryology experiment, Canadian scientists will conduct postflight experiments on live tadpoles brought back from space to determine whether larvae that develop from these embryos are behaviorally normal. Swimming kinematics in particular will be examined, since a distinctive looping behavior of Xenopus tadpoles under microgravity has been noted. A collaborative study with the Institute of Biomedical Problems in Moscow is designed to elucidate the relationship between buoyancy regulation and lung development in tadpoles, and is scheduled to fly on a Biocosmos satellite in 1992.
Optimized ex-ovo culturing of chick embryos to advanced stages of development.

PubMed

Cloney, Kellie; Franz-Odendaal, Tamara Anne

2015-01-24

Research in anatomy, embryology, and developmental biology has largely relied on the use of model organisms. In order to study development in live embryos model organisms, such as the chicken, are often used. The chicken is an excellent model organism due to its low cost and minimal maintenance, however they present observational challenges because they are enclosed in an opaque eggshell. In order to properly view the embryo as it develops, the shell must be windowed or removed. Both windowing and ex ovo techniques have been developed to assist researchers in the study of embryonic development. However, each of the methods has limitations and challenges. Here, we present a simple, optimized ex ovo culture technique for chicken embryos that enables the observation of embryonic development from stage HH 19 into late stages of development (HH 40), when many organs have developed. This technique is easy to adopt in both undergraduate classes and more advanced research laboratories where embryo manipulations are conducted.
[Ocular surface system integrity].

PubMed

Safonova, T N; Pateyuk, L S

2015-01-01

The interplay of different structures belonging to either the anterior segment of the eye or its accessory visual apparatus, which all share common embryological, anatomical, functional, and physiological features, is discussed. Explanation of such terms, as ocular surface, lacrimal functional unit, and ocular surface system, is provided.
Computer Simulation of Developmental Processes and Toxicities (SOT)

EPA Science Inventory

Rationale: Recent progress in systems toxicology and synthetic biology have paved the way to new thinking about in vitro/in silico modeling of developmental processes and toxicities, both for embryological and reproductive impacts. Novel in vitro platforms such as 3D organotypic ...
Teaching Evolution & the Nature of Science.

ERIC Educational Resources Information Center

Farber, Paul

2003-01-01

The theory of evolution provides direction in many fields, such as ecology, genetics, and embryology. Examines issues concerning the teaching of the subject in the United States. Presents a case study approach to teach about the nature of science using the theory of evolution. (SOE)
20180312 - Mechanistic Modeling of Developmental Defects through Computational Embryology (SOT)

EPA Science Inventory

Significant advances in the genome sciences, in automated high-throughput screening (HTS), and in alternative methods for testing enable rapid profiling of chemical libraries for quantitative effects on diverse cellular activities. While a surfeit of HTS data and information is n...
High-throughput screening, predictive modeling and computational embryology - Abstract

EPA Science Inventory

High-throughput screening (HTS) studies are providing a rich source of data that can be applied to chemical profiling to address sensitivity and specificity of molecular targets, biological pathways, cellular and developmental processes. EPA’s ToxCast project is testing 960 uniq...
The association of maternal thyroid function with placental hemodynamics.

PubMed

Barjaktarovic, M; Korevaar, T I M; Chaker, L; Jaddoe, V W V; de Rijke, Y B; Visser, T J; Steegers, E A P; Peeters, R P

2017-03-01

What is the clinical association of maternal thyroid function with placental hemodynamic function? A higher free thyroxine (FT4) concentration in early pregnancy is associated with higher placental vascular resistance. Suboptimal placental function is associated with preeclampsia (which, in turn, further deteriorates placental hemodynamics and impairs the fetal blood supply), fetal growth restriction and premature delivery. Studies have suggested that thyroid hormone (TH) has a role in placental development through effects on trophoblast proliferation and invasion. This study was embedded in The Generation R cohort, a population-based prospective study from early fetal life onwards in Rotterdam, the Netherlands. In total, 7069 mothers with expected delivery date between April 2002 and January 2006 were enrolled during early pregnancy. Thyroid-stimulating hormone (TSH) and free thyroxine (FT4) concentrations were measured during early pregnancy (median 13.4 weeks, 95% range 9.7-17.6 weeks). Placental function was assessed by Doppler ultrasound via measurement of arterial vascular resistance, i.e. umbilical artery pulsatility index (PI) and uterine artery resistance index (RI) (both measured twice, between 18-25th and after 25th gestational weeks) and the presence of uterine artery notching (once after the 25th gestational week) in 5184 pregnant women. FT4 was positively linearly associated with umbilical artery PI in the second and third trimesters as well as with uterine artery RI in the second trimester and the risk of uterine artery notching in the third trimester (P < 0.05 for all). The association of thyroid function with preeclampsia and birth weight was partially mediated through changes in placental function, with the percentages of mediated effects being 10.4% and 12.5%, respectively. A potential limitation is the availability of only a single time point for TH measurements and different numbers of missing placental ultrasound measurements for the adverse outcomes. A higher FT4 concentration in early pregnancy is associated with higher vascular resistance in the second and third trimesters in both the maternal and fetal placental compartment. These effects on placental function might explain the association of FT4 with adverse pregnancy outcomes, including preeclampsia and fetal growth restriction. This work was supported by a fellowship from ERAWEB, a project funded by the European Commission (to M.B.) and by clinical fellowship from The Netherlands Organization for Health Research and Development (ZonMw), Project 90700412 (to R.P.P.). The authors have no conflict of interest. N/A. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com
Ernst Haeckel's ontogenetic recapitulation: irritation and incentive from 1866 to our time.

PubMed

Sander, Klaus

2002-11-01

Ernst Haeckel (1834-1919) must count among the most widely known biologists of his time. His monographs on radiolarian skeletons, sponges and medusae immediately became standard works, owing partly to lavish illustrations that later on culminated in his "Art Forms in Nature", which markedly influenced the "art nouveau" of the early 20th century. Haeckel's main impact, however, came from his numerous popular books that were crucial in transferring Darwin's ideas to continental Europe. Haeckel's main addition was his claim that ontogeny recapitulates phylogeny. It was partly founded on pre-Darwinian observations by J.F. Meckel and K.E. v. Baer who noticed that vertebrate embryos of different species resemble each other more strongly during early ontogenesis than later on. Wishing to illustrate this clearly, Haeckel clandestinely generalized some figures showing early embryos of animals and Man. This "fraud" provided ammunition for his many adversaries, most of whom felt provoked by his antireligious campaigns. The resulting controversies continued well into the 20th century but then subsided. Quite recently, however, they have flared up again, perhaps in connection with progress in molecular embryology that revealed an amazing evolutionary conservation of genes and their cooperation in signal transduction chains. The scientific publications that triggered this flare, and a selection of "Letters to the Editor" in both international science magazines and the German popular press, serve here to show that Haeckel's idea of recapitulation, while having proven its heuristic value, is still causing considerable irritation. This results from the widespread intuition that the marvels of ontogenesis and other biological phenomena must reflect some "intelligent design" rather than Darwinian evolution.
Marshall Barber and the century of microinjection: from cloning of bacteria to cloning of everything.

PubMed

Korzh, Vladimir; Strähle, Uwe

2002-08-01

A hundred years ago, Dr. Marshall A. Barber proposed a new technique - the microinjection technique. He developed this method initially to clone bacteria and to confirm the germ theory of Koch and Pasteur. Later on, he refined his approach and was able to manipulate nuclei in protozoa and to implant bacteria into plant cells. Continuous improvement and adaptation of this method to new applications dramatically changed experimental embryology and cytology and led to the formation of several new scientific disciplines including animal cloning as one of its latest applications. Interestingly, microinjection originated as a method at the crossroad of bacteriology and plant biology, demonstrating once again the unforeseen impact that basic research in an unrelated field can have on the development of entirely different disciplines.
A new classification system for congenital laryngeal cysts.

PubMed

Forte, Vito; Fuoco, Gabriel; James, Adrian

2004-06-01

A new classification system for congenital laryngeal cysts based on the extent of the cyst and on the embryologic tissue of origin is proposed. Retrospective chart review. The charts of 20 patients with either congenital or acquired laryngeal cysts that were treated surgically between 1987 and 2002 at the Hospital for Sick Children, Toronto were retrospectively reviewed. Clinical presentation, radiologic findings, surgical management, histopathology, and outcome were recorded. A new classification system is proposed to better appreciate the origin of these cysts and to guide in their successful surgical management. Fourteen of the supraglottic and subglottic simple mucous retention cysts posed no diagnostic or therapeutic challenge and were treated successfully by a single endoscopic excision or marsupialization. The remaining six patients with congenital cysts in the study were deemed more complex, and all required open surgical procedures for cure. On the basis of the analysis of the data of these patients, a new classification of congenital laryngeal cysts is proposed. Type I cysts are confined to the larynx, the cyst wall composed of endodermal elements only, and can be managed endoscopically. Type II cysts extend beyond the confines of the larynx and require an external approach. The Type II cysts are further subclassified histologically on the basis of the embryologic tissue of origin: IIa, composed of endoderm only and IIb, containing endodermal and mesodermal elements (epithelium and cartilage) in the wall of the cyst. A new classification system for congenital laryngeal cysts is proposed on the basis of the extent of the cyst and the embryologic tissue of origin. This classification can help guide the surgeon with initial management and help us better understand the origin of these cysts.
Unfolding a chordate developmental program, one cell at a time: invariant cell lineages, short-range inductions and evolutionary plasticity in ascidians.

PubMed

Lemaire, Patrick

2009-08-01

Ascidians were historically the first metazoans in which experimental embryology was carried out. These early works by Chabry and Conklin [Chabry, L., 1887. Embryologie normale et tératologique des Ascidie. Felix Alcan Editeur, Paris; Conklin, E., 1905. The organization and cell lineage of the ascidian egg. J. Acad., Nat. Sci. Phila. 13, 1], in particular, led to the idea that the developmental program of these animals was driven by the cell-autonomous inheritance of localised maternal determinants, rendered precise by the stereotyped pattern of invariant cell cleavages. Work in the past 20 years indeed identified several localised maternal determinants of the position of cleavage planes or of some early cell fates. The overwhelming majority of cells in the three germ layers, however, do not follow a cell-autonomous differentiation program. Instead, they respond to short-range signals, as described in this review. Careful analysis of cell-cell contacts suggests that a major function of the invariant position of cleavage plans, besides segregating competence factors, is to control the relative positions of inducing cells and those competent to respond. Surprisingly, while the cell lineage is very well conserved between the divergent species Halocynthia roretzi and Ciona intestinalis, the molecular nature of inducing signals can vary. The constraints on embryo anatomy thus appear stronger than those on the choice of individual regulatory molecules.
Hearing, speech, language, and vestibular disorders in the fetal alcohol syndrome: a literature review.

PubMed

Church, M W; Kaltenbach, J A

1997-05-01

Fetal alcohol syndrome (FAS) is characterized in part by mental impairment, as well as craniofacial and ocular anomalies. These conditions are traditionally associated with childhood hearing disorders, because they all have a common embryonic origin in malformations of the first and second branchial arches, and have similar critical periods of vulnerability to toxic insult. A review of human and animal research indicates that there are four types of hearing disorders associated with FAS. These are: (1) a developmental delay in auditory maturation, (2) sensorineural hearing loss, (3) intermittent conductive hearing loss due to recurrent serous otitis media, and (4) central hearing loss. The auditory and vestibular systems share the same peripheral apparatuses (the inner ear and eighth cranial nerve) and are embryologically and structurally similar. Consequently, vestibular disorders in FAS children might be expected. The evidence for vestibular dysfunction in FAS is ambiguous, however. Like other syndromes associated with craniofacial anomalies, hearing disorders, and mental impairment, FAS is also characterized by a high prevalence of speech and language pathology. Hearing disorders are a form of sensory deprivation. If present during early childhood, they can result in permanent hearing, language, and mental impairment. Early identification and intervention to treat hearing, language, and speech disorders could therefore result in improved outcome for the FAS child. Specific recommendations are made for intervention and future research.
EMBRYOLOGICAL ORIGIN FOR AUTISM: DEVELOPMENTAL ANOMALIES OF THE CRANIAL NERVE MOTOR NUCLEI. (R824758)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...
Multiscale Systems Modeling of Male Reproductive Tract Defects: from Genes to Populations (SOT)

EPA Science Inventory

The reproductive tract is a complex, integrated organ system with diverse embryology and unique sensitivity to prenatal environmental exposures that disrupt morphoregulatory processes and endocrine signaling. U.S. EPA’s in vitro high-throughput screening (HTS) database (ToxCastDB...
Mechanistic modeling of developmental defects through computational embryology (WC10th)

EPA Science Inventory

Abstract: An important consideration for 3Rs is to identify developmental hazards utilizing mechanism-based in vitro assays (e.g., ToxCast) and in silico predictive models. Steady progress has been made with agent-based models that recapitulate morphogenetic drivers for angiogen...
Textbook of Uroradiology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dunnick, N.R.; McCallum, R.W.; Sandler, C.M.

1991-01-01

This book provides the practicing radiologist and the radiology resident with a comprehensive text of manageable size that integrates all aspects of adult uroradiology. Topics covered include: anatomy, embryology, and cogenital anomalies of the urinary tract; techniques for imaging of the urinary tract; contrast material; pathologies; and interventional uroradiology.
Unravelling the ambiguous reproductive biology of Paspalum malacophyllum: a decades old story clarified

USDA-ARS?s Scientific Manuscript database

A recent a manuscript was published by our group that analyzed the reproductive biology of the grass species Paspalum malacophyllum using traditional embryological techniques combined with current cytological and molecular methods. Our findings confirmed apparent contradictions regarding the reprod...

High-throughput screening, predictive modeling and computational embryology

EPA Science Inventory

High-throughput screening (HTS) studies are providing a rich source of data that can be applied to profile thousands of chemical compounds for biological activity and potential toxicity. EPA’s ToxCast™ project, and the broader Tox21 consortium, in addition to projects worldwide,...
Homologies of the meningeal-orbital arteries of humans: a reappraisal.

PubMed Central

Diamond, M K

1991-01-01

Two arteries connect the anterior branch of the middle meningeal artery to the lacrimal artery. One vessel, the sphenoidal artery, passes through the superior orbital fissure. The other vessel, the meningolacrimal artery, passes through the cranio-orbital foramen. An analysis of data derived from embryology, comparative anatomy, and patterns of adult variation indicates that the meningolacrimal artery is homologous with the ramus superior of the stapedial artery, an embryologically and phylogenetically primitive vessel. The sphenoidal artery probably forms late in human ontogeny and represents an evolutionary novelty. Its distribution is probably restricted to hominoids and may be exclusive to humans and orangutans (Pongo pygmaeus). The sphenoidal artery is associated with three other derived features: the sphenoparietal sinus and sulcus and a laterally expanded superior orbital fissure. The high frequency of the sphenoidal artery in Homo and Pongo probably represents a case of parallelism. The earliest paleontological evidence of an enlarged sphenoidal artery in the Hominidae occurs in Indonesian Homo erectus (Sangiran VI). PMID:1810930
Cryopreservation of animal oocytes and embryos: Current progress and future prospects.

PubMed

Mandawala, A A; Harvey, S C; Roy, T K; Fowler, K E

2016-10-15

Cryopreservation describes techniques that permit freezing and subsequent warming of biological samples without loss of viability. The application of cryopreservation in assisted reproductive technology encompasses the freezing of gametes, embryos, and primordial germ cells. Whilst some protocols still rely on slow-freezing techniques, most now use vitrification, or ultra-rapid freezing, for both oocytes and embryos due to an associated decreased risk of damage caused by the lack of ice crystal formation, unlike in slow-freezing techniques. Vitrification has demonstrated its use in many applications, not only following IVF procedures in human embryology clinics but also following in vitro production of embryos in agriculturally important, or endangered animal species, before embryo transfer. Here, we review the various cryopreservation and vitrification technologies that are used in both humans and other animals and discuss the most recent innovations in vitrification with a particular emphasis on their applicability to animal embryology. Copyright © 2016 Elsevier Inc. All rights reserved.
The zebrafish as a model system to study cardiovascular development.

PubMed

Stainier, D Y; Fishman, M C

1994-01-01

The zebrafish, Brachydanio rerio, is rapidly becoming a system of choice for vertebrate developmental biologists. It presents unique embryological attributes and is amenable to saturation style mutagenesis, a powerful approach that, in invertebrates, has already led to the identification of a large number of key developmental genes. Since fertilization is external, the zebrafish embryo develops in the dish and is thus accessible for continued observation and manipulation at all stages of development. Furthermore, because the embryo is transparent, the developing heart and vessels can be resolved at the single-cell level. A large number of mutations that affect the development of cardiovascular form and function have recently been isolated from large-scale genetic screens for zygotic embryonic lethals. Our further understanding of the development of the cardiovascular system is important not only because of the high incidence, and familial inheritance, of congenital abnormalities, but also because it should lead to novel, differentiation-based strategies for the analysis and therapy of the diseased state. Copyright © 1994. Published by Elsevier Inc.
The Megameatus, Intact Prepuce Variant of Hypospadias: Use of the Inframeatal Vascularized Flap for Surgical Correction.

PubMed

Cendron, Marc

2018-01-01

The megameatus intact prepuce (MIP) variant of hypospadias is a rare variant of hypospadias that is diagnosed either early at the time of circumcision or later as the foreskin is retracted. The true incidence of the anomaly is difficult to determine precisely as some patient never come to medical attention but is felt to under 5% of all cases of hypospadias. The purposes of this study are to review the embryology and clinical findings of MIP and then, in light of a personal experience, present a series of patients evaluated for MIP who were treated with a modification of the Mathieu technique. A PubMed search of all articles in the MIP variant of hypospadias was carried out followed by an exhaustive review of the literature. The charts of all patients evaluated and treated at Boston Children's Hospital by MC between 2007 and 2017 were reviewed retrospectively. The patients were divided into two groups: those who underwent the standard procedure and those who underwent a repair using a modification of the Mathieu procedure using an inframeatal flap. The embryologic explanation of the MIP variant is not clear but failure of the distal, glanular portion of the urethra to tubularize results in spectrum of abnormality characterized by a deep glanular groove and an abnormal opening of the urethra anywhere from the mid-glans to a subcoronal location. Surgical repair is complicated by a wide distal urethra which may be injured if not properly identified. Overall good outcomes were noted with one patient experiencing a urethra cutaneous fistula in the first group and one patient having a mild glans dehiscence in the second. The MIP variant of hypospadias is a rare variant of hypospadias that presents as a spectrum of urethral anomaly. Surgical repair may not always be necessary but if surgical repair is carried out, the Mathieu technique modification may offer better anatomic delineation of the urethra and will provide an extra layer of tissue to cover the reconstructed urethra. Low complication rates should be expected with adequate functional outcome such as a normal urinary stream. In addition, criteria for selecting patients for surgical repair are provided.
Aquinas's account of human embryogenesis and recent interpretations.

PubMed

Eberl, Jason T

2005-08-01

In addressing bioethical issues at the beginning of human life, such as abortion, in vitro fertilization, and embryonic stem cell research, one primary concern regards establishing when a developing human embryo or fetus can be considered a person. Thomas Aquinas argues that an embryo or fetus is not a human person until its body is informed by a rational soul. Aquinas's explicit account of human embryogenesis has been generally rejected by contemporary scholars due to its dependence upon medieval biological data, which has been far surpassed by current scientific research. A number of scholars, however, have attempted to combine Aquinas's basic metaphysical account of human nature with current embryological data to develop a contemporary Thomistic account of a human person's beginning. In this article, I discuss two recent interpretations in which it is argued that a human person does not begin to exist until a fetus has developed a functioning cerebral cortex.
The endoskeletal origin of the turtle carapace

PubMed Central

Hirasawa, Tatsuya; Nagashima, Hiroshi; Kuratani, Shigeru

2013-01-01

The turtle body plan, with its solid shell, deviates radically from those of other tetrapods. The dorsal part of the turtle shell, or the carapace, consists mainly of costal and neural bony plates, which are continuous with the underlying thoracic ribs and vertebrae, respectively. Because of their superficial position, the evolutionary origins of these costo-neural elements have long remained elusive. Here we show, through comparative morphological and embryological analyses, that the major part of the carapace is derived purely from endoskeletal ribs. We examine turtle embryos and find that the costal and neural plates develop not within the dermis, but within deeper connective tissue where the rib and intercostal muscle anlagen develop. We also examine the fossils of an outgroup of turtles to confirm that the structure equivalent to the turtle carapace developed independently of the true osteoderm. Our results highlight the hitherto unravelled evolutionary course of the turtle shell. PMID:23836118
Anatomy and development of the meninges: implications for subdural collections and CSF circulation.

PubMed

Mack, Julie; Squier, Waney; Eastman, James T

2009-03-01

The dura is traditionally viewed as a supportive fibrous covering of the brain containing the dural venous sinuses but otherwise devoid of vessels and lacking any specific function. However, review of the embryology and anatomy reveals the dura to be a complex, vascularized and innervated structure, not a simple fibrous covering. The dura contains an inner vascular plexus that is larger in the infant than in the adult, and this plexus likely plays a role in CSF absorption. This role could be particularly important in the infant whose arachnoid granulations are not completely developed. Although subdural hemorrhage is frequently traumatic, there are nontraumatic conditions associated with subdural hemorrhage, and the inner dural plexus is a likely source of bleeding in these nontraumatic circumstances. This review outlines the development and age-specific vascularity of the dura and offers an alternative perspective on the role of the dura in homeostasis of the central nervous system.
A Three Dimension Model to Demonstrate Head and Tail Fold Formation in Mammalian Embryos

ERIC Educational Resources Information Center

Bressler, Robert S.

1977-01-01

Many students have difficulty visualizing the delineation of the embryonic body from the flat germ disc. An easily-constructed model is described that has been used successfully to convey the dynamics of embryological events at Mount Sinai School of Medicine. (LBH)
The Role of DN-GSK3beta in Mammary Tumorigenesis

DTIC Science & Technology

2006-07-01

factors and dramatically increases their transcriptional activity. Genes up- regulated by TCF/LEF include embryologic genes, such as siamois and engrailed...and increased apoptosis occurs in the mammary epithelia (33). Overexpression of the regulator CK2a also promotes mammary tumorigenesis (34). In this
An H-shaped complete ureteric duplication: embryology or erosion

PubMed Central

Jayasekera, Ashan; Tempest, Heidi; Kumar, Sunil

2011-01-01

The authors report the case of a duplex urinary collecting system that forms a single chamber about 2 cm proximal to the bladder with distal bifurcation and drainage into the bladder via distinct ureteric orifices. This anatomical variant has not been described before. PMID:22691584
Posterior Circulation Moyamoya Disease versus Primitive Vertebral-Basilar Artery System Moyamoya Disease: New Classification of Moyamoya Disease from the Perspective of Embryology.

PubMed

Tan, Cunxin; Duan, Ran; Ye, Xun; Zhang, Dong; Wang, Rong

2016-12-01

Moyamoya disease (MMD) is a chronic cerebrovascular disorder with little known etiology. We aim to propose a new classification system for MMD from the perspective of embryology. MMD patients' digital subtraction angiograms were retrospectively analyzed. Every angiogram was analyzed to find the abnormal vessels and from which part of the posterior cerebral artery (PCA) the lesions begin. In 262 MMD cases, 32 pediatric patients had PCA involvement, of which 17 were male and 15 were female; 68 adults had PCA involvement, of which 33 were male and 35 were female. The initially affected part of the PCA was compared between sexes and between pediatric and adult patients, and the findings are not statistically significant (P = 0.233, P = 0.855, P = 0.343, respectively). However, of the 100 cases with PCA involvement, only 4 had the lesions begin from the first part of the PCA, and all of the 4 cases had the basilar artery lesions. All the other 96 cases had the lesions begin from the second part of the PCA or from the posterior communication artery, which is derived from the caudal ramus of the primitive intracarotid artery, leaving the first part of the PCA and basilar artery excluded from affection. MMD should be classified into primitive intracarotid artery system-involved type and primitive vertebral basilar artery system-involved type. The reason that the vertebral basilar artery is so rarely involved in MMD might be because of its late development in the brain. Copyright Â© 2016 Elsevier Inc. All rights reserved.
Reasonable classical concepts in human lower limb anatomy from the viewpoint of the primitive persistent sciatic artery and twisting human lower limb.

PubMed

Kawashima, Tomokazu; Sasaki, Hiroshi

2010-11-01

The main aim of this review is (1) to introduce the two previous studies we published human lower limb anatomy based on the conventional macroscopic anatomical [corrected] criteria with hazardous recognition of this description, (2) to activate the discussion whether the limb homology exists, and (3) to contribute to future study filling the gap between the gross anatomy and embryology. One of the topics we discussed was the human persistent sciatic artery. To date, numerous human cases of persistent sciatic artery have been reported in which the anomalous artery was present in the posterior compartment of the thigh alongside the sciatic nerve. As one of the important criteria for assessing the human primitive sciatic artery, its ventral arterial position with respect to the sciatic nerve is reasonable based on the initial positional relationship between ventral arterial and dorsal nervous systems and comparative anatomical findings. We also discuss ways of considering the topography of muscles of the lower limb and their innervations compared to those of the upper limb. We propose a schema of the complex anatomical characteristics of the lower limb based on the vertebrate body plan. According to this reasonable schema, the twisted anatomy of the lower limb can be understood more easily. These two main ideas discussed in this paper will be useful for further understanding of the anatomy of the lower limb and as a first step for future. We hope that the future study in lower limb will be further developed by both viewpoints of the classical gross anatomy and recent embryology.
[Contribution of pelvic echography to the diagnosis of malformations of the utero-vaginal tract].

PubMed

Ellart, D; Houze de l'Aulnoit, H; Corette, L; Delcroix, M; Brabant, G

1990-01-01

Pelvic ultrasound has become very important in the diagnostic planning of utero-vaginal malformations. Having studies 93 congenital malformations of the utero-vaginal tract, the authors used ultrasound investigations as a first or second line of approach. They are able to describe the way ultrasound can be used for each type of malformation. Ultrasound is undeniably reliable for diagnosing bilateral incomplete aplasia of the uterus; so avoiding the need for laparoscopy. When failure of the uterus to develop on one side occurs it is possible to look for a closed or canalized rudimentary uterine nodule to confirm the diagnosis of a pseudo-unicorn uterus. The diagnosis by ultrasound of a bifid uterus shows up by the appearance of a "V" shape on the bladder. An intra-uterine septum can be diagnosed according to how serious the embryological abnormality is on ultrasound. Similarly the difference between a bicornuate uterus that is really just arcuate or partially septate cannot always be made with ultrasound because the embryological defect is a relatively minor one. Ultrasound examination is able to give a lot of information in diagnosing and calculating how much of the menstrual fluid is held back either on one side or completely. Its value is less when the two sides of the uterus communicate with one another. Although this way of examining patients may make it possible quite often to avoid carrying out hysterosalpingogram and laparoscopy, its greatest value is found when all methods of diagnosis are combined and interpreted in the context of a clinical situation.
Semi-thin sections of epoxy resin-embedded mouse embryos in morphological analysis of whole mount in situ RNA hybridization.

PubMed

Mitrecić, D; Cunko, V F; Gajović, S

2008-12-01

Descriptive morphological studies are often combined with gene expression pattern analyses. Unembedded vibratome or cryotome sections are compatible with in situ RNA hybridization, but spatial resolution is rather low for precise microscopic studies necessary in embryology. Therefore, use of plastic embedding media, which allow semi-thin and ultra-thin sectioning for light and electron microscopy, could be an important advantage. This work suggested a new approach based on the whole mount hybridization of mouse embryos and subsequent epoxy resin embedding. Epoxy resin allowed serial sectioning of semi-thin sections with preserved in situ RNA hybridization signal, which was a necessary prerequisite for precise morphological analysis of embryo development.
[Right-side aortic arch with aberrant left subclavian artery and Kommerell's diverticulum. A cause of vascular ring].

PubMed

Tamayo-Espinosa, Tania; Erdmenger-Orellana, Julio; Becerra-Becerra, Rosario; Balderrabano-Saucedo, Norma; Segura-Standford, Begoña

The right-side aortic arch may be associated with aberrant left subclavian artery, in some cases this artery originates from an aneurismal dilation of the aorta called Kommerell's diverticulum. A report is presented on 2 cases of vascular ring formed by a right-side aortic arch, anomalous left subclavian artery, Kommerell's diverticulum and left patent ductus arteriosus. A review the literature was also performed as regards the embryological development and the imaging methods used to help in the diagnosis of this rare vascular anomaly. Copyright © 2017 Instituto Nacional de Cardiología Ignacio Chávez. Publicado por Masson Doyma México S.A. All rights reserved.
Congenital hemangioma in spondylocostal dysostosis: a novel association*

PubMed Central

Salinas-Torres, Victor Michael

2016-01-01

Congenital hemangioma is a benign tumor caused by dysfunction in embryogenesis and vasculogenesis, which progresses during fetal life to manifest as fully developed at birth. Although hemangiomas are the most common tumor of infancy, rapidly involuting congenital hemangioma has not been described in spondylocostal dysostosis. I report the novel association of congenital hemangioma and spondylocostal dysostosis in a Mexican newborn female patient with neural tube defects. Given the embryological relationship between skin and nervous system, I surmise that this association is not coincidental. I also propose that these morphologic alterations be incorporated to the spondylocostal dysostosis phenotype and specifically looked for in other affected children, in order to provide appropriate medical management and genetic counseling. PMID:28300884
Congenital hemangioma in spondylocostal dysostosis: a novel association.

PubMed

Salinas-Torres, Victor Michael

2016-01-01

Congenital hemangioma is a benign tumor caused by dysfunction in embryogenesis and vasculogenesis, which progresses during fetal life to manifest as fully developed at birth. Although hemangiomas are the most common tumor of infancy, rapidly involuting congenital hemangioma has not been described in spondylocostal dysostosis. I report the novel association of congenital hemangioma and spondylocostal dysostosis in a Mexican newborn female patient with neural tube defects. Given the embryological relationship between skin and nervous system, I surmise that this association is not coincidental. I also propose that these morphologic alterations be incorporated to the spondylocostal dysostosis phenotype and specifically looked for in other affected children, in order to provide appropriate medical management and genetic counseling.
Lumbar Facet Tropism: A Comprehensive Review.

PubMed

Alonso, Fernando; Kirkpatrick, Christina M; Jeong, William; Fisahn, Christian; Usman, Sameera; Rustagi, Tarush; Loukas, Marios; Chapman, Jens R; Oskouian, Rod J; Tubbs, R Shane

2017-06-01

Scattered reports exist in the medical literature regarding facet tropism. However, this finding has had mixed conclusions regarding its origin and impact on the normal spine. We performed a literature review of the anatomy, embryology, biomechanics, and pathology related to lumbar facet tropism. Facet tropism is most commonly found at L4-L5 vertebral segments and there is some evidence that this condition may lead to facet degenerative spondylolisthesis, intervertebral disc disease, and other degenerative conditions. Long-term analyses of patients are necessary to elucidate relationships between associated findings and facet tropism. In addition, a universally agreed definition that is more precise should be developed for future investigative studies. Copyright © 2017 Elsevier Inc. All rights reserved.
The evolutionary origin of the vertebrate body plan: the problem of head segmentation.

PubMed

Onai, Takayuki; Irie, Naoki; Kuratani, Shigeru

2014-01-01

The basic body plan of vertebrates, as typified by the complex head structure, evolved from the last common ancestor approximately 530 Mya. In this review, we present a brief overview of historical discussions to disentangle the various concepts and arguments regarding the evolutionary development of the vertebrate body plan. We then explain the historical transition of the arguments about the vertebrate body plan from merely epistemological comparative morphology to comparative embryology as a scientific treatment on this topic. Finally, we review the current progress of molecular evidence regarding the basic vertebrate body plan, focusing on the link between the basic vertebrate body plan and the evolutionarily conserved developmental stages (phylotypic stages).

New developmental evidence supports a homeotic frameshift of digit identity in the evolution of the bird wing

PubMed Central

2014-01-01

Background The homology of the digits in the bird wing is a high-profile controversy in developmental and evolutionary biology. The embryonic position of the digits cartilages with respect to the primary axis (ulnare and ulna) corresponds to 2, 3, 4, but comparative-evolutionary morphology supports 1, 2, 3. A homeotic frameshift of digit identity in evolution could explain how cells in embryonic positions 2, 3, 4 began developing morphologies 1, 2, 3. Another alternative is that no re-patterning of cell fates occurred, and the primary axis shifted its position by some other mechanism. In the wing, only the anterior digit lacks expression of HoxD10 and HoxD12, resembling digit 1 of other limbs, as predicted by 1, 2, 3. However, upon loss of digit 1 in evolution, the most anterior digit 2 could have lost their expression, deceitfully resembling a digit 1. To test this notion, we observed HoxD10 and HoxD12 in a limb where digit 2 is the most anterior digit: The rabbit foot. We also explored whether early inhibition of Shh signalling in the embryonic wing bud induces an experimental homeotic frameshift, or an experimental axis shift. We tested these hypotheses using DiI injections to study the fate of cells in these experimental wings. Results We found strong transcription of HoxD10 and HoxD12 was present in the most anterior digit 2 of the rabbit foot. Thus, we found no evidence to question the use of HoxD expression as support for 1, 2, 3. When Shh signalling in early wing buds is inhibited, our fate maps demonstrate that an experimental homeotic frameshift is induced. Conclusion Along with comparative morphology, HoxD expression provides strong support for 1, 2, 3 identity of wing digits. As an explanation for the offset 2, 3, 4 embryological position, the homeotic frameshift hypothesis is consistent with known mechanisms of limb development, and further proven to be experimentally possible. In contrast, the underlying mechanisms and experimental plausibility of an axis shift remain unclear. PMID:24725625
New developmental evidence supports a homeotic frameshift of digit identity in the evolution of the bird wing.

PubMed

Salinas-Saavedra, Miguel; Gonzalez-Cabrera, Cristian; Ossa-Fuentes, Luis; Botelho, Joao F; Ruiz-Flores, Macarena; Vargas, Alexander O

2014-04-12

The homology of the digits in the bird wing is a high-profile controversy in developmental and evolutionary biology. The embryonic position of the digits cartilages with respect to the primary axis (ulnare and ulna) corresponds to 2, 3, 4, but comparative-evolutionary morphology supports 1, 2, 3. A homeotic frameshift of digit identity in evolution could explain how cells in embryonic positions 2, 3, 4 began developing morphologies 1, 2, 3. Another alternative is that no re-patterning of cell fates occurred, and the primary axis shifted its position by some other mechanism. In the wing, only the anterior digit lacks expression of HoxD10 and HoxD12, resembling digit 1 of other limbs, as predicted by 1, 2, 3. However, upon loss of digit 1 in evolution, the most anterior digit 2 could have lost their expression, deceitfully resembling a digit 1. To test this notion, we observed HoxD10 and HoxD12 in a limb where digit 2 is the most anterior digit: The rabbit foot. We also explored whether early inhibition of Shh signalling in the embryonic wing bud induces an experimental homeotic frameshift, or an experimental axis shift. We tested these hypotheses using DiI injections to study the fate of cells in these experimental wings. We found strong transcription of HoxD10 and HoxD12 was present in the most anterior digit 2 of the rabbit foot. Thus, we found no evidence to question the use of HoxD expression as support for 1, 2, 3. When Shh signalling in early wing buds is inhibited, our fate maps demonstrate that an experimental homeotic frameshift is induced. Along with comparative morphology, HoxD expression provides strong support for 1, 2, 3 identity of wing digits. As an explanation for the offset 2, 3, 4 embryological position, the homeotic frameshift hypothesis is consistent with known mechanisms of limb development, and further proven to be experimentally possible. In contrast, the underlying mechanisms and experimental plausibility of an axis shift remain unclear.
Proposal of a model of mammalian neural induction

PubMed Central

Levine, Ariel J.; Brivanlou, Ali H.

2009-01-01

How does the vertebrate embryo make a nervous system? This complex question has been at the center of developmental biology for many years. The earliest step in this process – the induction of neural tissue – is intimately linked to patterning of the entire early embryo, and the molecular and embryological basis these processes are beginning to emerge. Here, we analyze classic and cutting-edge findings on neural induction in the mouse. We find that data from genetics, tissue explants, tissue grafting, and molecular marker expression support a coherent framework for mammalian neural induction. In this model, the gastrula organizer of the mouse embryo inhibits BMP signaling to allow neural tissue to form as a default fate – in the absence of instructive signals. The first neural tissue induced is anterior and subsequent neural tissue is posteriorized to form the midbrain, hindbrain, and spinal cord. The anterior visceral endoderm protects the pre-specified anterior neural fate from similar posteriorization, allowing formation of forebrain. This model is very similar to the default model of neural induction in the frog, thus bridging the evolutionary gap between amphibians and mammals. PMID:17585896
TRANSITIONAL CELL CANCER OF THE ANUS AND RECTUM

PubMed Central

Grodsky, Lewis

1961-01-01

A study was made of all cases of transitional cell cancer of the anus or rectum in the records of the University of California Medical Center, San Francisco. None was listed until 1945, then an additional seven between 1954 and 1960. During the latter period there were 192 cases of adenocarcinoma of the rectum, six cases of squamous cell or epidermoid rectal cancer and 12 cases of squamous cell cancer of the anus. Distinctive and highly malignant anal and rectal epithelial tumors will occasionally arise at or near the anorectal junction from inconstant embryologic entodermal cloacal vestiges. These atypical nonkeratinizing lesions are very similar microscopically to transitional cell tumors found in the cloacogenic portions of the lower genitourinary tract. Review of the literature indicates that the prognosis of cloacogenic anal and rectal lesions appears to be relatively graver than that for the more common adenocarcinomas and keratinizing squamous cell epitheliomas. Early diagnosis and prompt, radical excision seem to offer the only hope for survival. ImagesFigure 1.Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7 PMID:13902070
Mitogenomics and phylogenomics reveal priapulid worms as extant models of the ancestral Ecdysozoan.

PubMed

Webster, Bonnie L; Copley, Richard R; Jenner, Ronald A; Mackenzie-Dodds, Jacqueline A; Bourlat, Sarah J; Rota-Stabelli, Omar; Littlewood, D T J; Telford, Maximilian J

2006-01-01

Research into arthropod evolution is hampered by the derived nature and rapid evolution of the best-studied out-group: the nematodes. We consider priapulids as an alternative out-group. Priapulids are a small phylum of bottom-dwelling marine worms; their tubular body with spiny proboscis or introvert has changed little over 520 million years and recognizable priapulids are common among exceptionally preserved Cambrian fossils. Using the complete mitochondrial genome and 42 nuclear genes from Priapulus caudatus, we show that priapulids are slowly evolving ecdysozoans; almost all these priapulid genes have evolved more slowly than nematode orthologs and the priapulid mitochondrial gene order may be unchanged since the Cambrian. Considering their primitive bodyplan and embryology and the great conservation of both nuclear and mitochondrial genomes, priapulids may deserve the popular epithet of "living fossil." Their study is likely to yield significant new insights into the early evolution of the Ecdysozoa and the origins of the arthropods and their kin as well as aiding inference of the morphology of ancestral Ecdysozoa and Bilateria and their genomes.
What are Head Cavities? - A History of Studies on Vertebrate Head Segmentation.

PubMed

Kuratani, Shigeru; Adachi, Noritaka

2016-06-01

Motivated by the discovery of segmental epithelial coeloms, or "head cavities," in elasmobranch embryos toward the end of the 19th century, the debate over the presence of mesodermal segments in the vertebrate head became a central problem in comparative embryology. The classical segmental view assumed only one type of metamerism in the vertebrate head, in which each metamere was thought to contain one head somite and one pharyngeal arch, innervated by a set of cranial nerves serially homologous to dorsal and ventral roots of spinal nerves. The non-segmental view, on the other hand, rejected the somite-like properties of head cavities. A series of small mesodermal cysts in early Torpedo embryos, which were thought to represent true somite homologs, provided a third possible view on the nature of the vertebrate head. Recent molecular developmental data have shed new light on the vertebrate head problem, explaining that head mesoderm evolved, not by the modification of rostral somites of an amphioxus-like ancestor, but through the polarization of unspecified paraxial mesoderm into head mesoderm anteriorly and trunk somites posteriorly.
The role of tumor microenvironment in development and progression of malignant melanomas - a systematic review.

PubMed

Gurzu, Simona; Beleaua, Marius Alexandru; Jung, Ioan

2018-01-01

To reveal the particular aspects of the tumor microenvironment of malignant melanomas, a systematic review including 34 representative papers was performed. The review took into account the aspects related the Wnt/β-catenin pathway-related epithelial-mesenchymal transition (EMT) versus mesenchymal-epithelial transition (MET) of keratinocytes, fibroblasts and melanoma cells, as possible tools for understanding genesis and evolution of malignant melanoma. The possible reversible features of EMT and the role of tumor microenvironment in the metastatic process were also analyzed. A particular issue was related on the cancer stem cells that include melanocyte stem cells (McSCs) and multipotent mesenchymal stem/stromal cells (MSCs). As the McSCs embryological development in mouse is not similar to human development, the role of stem cells in genesis and development of human melanoma should be proved in human melanoma cells only. For further development of targeted therapy, a better understanding of melanomagenesis pathways and its microenvironment particularities is necessary.
A heterozygous microdeletion of 20p12.2-3 encompassing PROKR2 and BMP2 in a patient with congenital hypopituitarism and growth hormone deficiency.

PubMed

Parsons, Samuel J H; Wright, Neville B; Burkitt-Wright, Emma; Skae, Mars S; Murray, Phillip G

2017-08-01

Congenital growth hormone deficiency is a rare disorder with an incidence of approximately 1 in 4,000 live births. Pituitary development is under the control of a multitude of spatiotemporally regulated signaling molecules and transcription factors. Mutations in the genes encoding these molecules can result in hypopituitarism but for the majority of children with congenital hypopituitarism, the aetiology of their disease remains unknown. The proband is a 5-year-old girl who presented with neonatal hypoglycaemia and prolonged jaundice. No definitive endocrine cause of hypoglycaemia was identified in the neonatal period. She was born of normal size at 42 weeks but demonstrated growth failure with a progressive reduction in height to -3.2 SD by age 4.5 years and failed a growth hormone stimulation test with a peak growth hormone of 4.2 mcg/L. MRI of the pituitary gland demonstrated a hypoplastic anterior lobe and ectopic posterior lobe. Array CGH demonstrated an inherited 0.2 Mb gain at 1q21.1 and a de novo 4.8 Mb heterozygous deletion at 20p12.2-3. The deletion contained 17 protein coding genes including PROKR2 and BMP2, both of which are expressed during embryological development of the pituitary gland. PROKR2 mutations have been associated with hypopituitarism but a heterozygous deletion of this gene with hypopituitarism is a novel observation. In conclusion, congenital hypopituitarism can be present in individuals with a 20p12.3 deletion, observed with incomplete penetrance. Array CGH may be a useful investigation in select cases of early onset growth hormone deficiency, and patients with deletions within this region should be evaluated for pituitary hormone deficiencies. © 2017 Wiley Periodicals, Inc.
Invertebrate predation on egg masses of the European cuttlefish, Sepia officinalis: An experimental approach

NASA Astrophysics Data System (ADS)

Martins, Catarina P. P.; Fernández-Álvarez, Fernando Á.; Villanueva, Roger

2018-01-01

The eggs of the European cuttlefish, Sepia officinalis, develop attached to the seafloor in shallow water habitats and possess a relatively thick black capsule that protects them from the surrounding environment. Since embryological development may take several months, eggs are vulnerable to a variety of threats present in shallow waters, including predation. This study investigates predation of S. officinalis eggs by benthic invertebrates. Twenty-eight invertebrate species from 6 different phyla and with diverse feeding habits were tested as potential predators under laboratory conditions. We also investigated how the feeding traits of these species are related to the mechanical ability to break the egg capsule and prey upon cuttlefish embryos. Species that fed on cuttlefish eggs were the sea snail Bolinus brandaris, the crab Cancer pagurus, the hermit crab Dardanus arrosor, the lobster Homarus gammarus, the invasive blue crab Callinectes sapidus, the shrimp Squilla mantis, the sea urchins Echinus melo, Cidaris sp. and Paracentrotus lividus and the starfish Astropecten aranciacus. It is of note that C. sapidus is a potential predatory crab, which raises the concern that this invasive species may constitute a novel threat for cuttlefish eggs as more populations become established in NE Atlantic waters. Of the biological traits examined, prey capture tools in the tested species best explained the experimental feeding results, suggesting that predation of S. officinalis eggs was determined generally by a mechanical factor and highlighting the importance of the protective egg capsule against predators. However, chemosensory factors are likely to be implicated as well. Thus, this work contributes to the understanding of the ecology of early life stages of cuttlefish and the factors that can affect offspring survival and subsequently impact the recruitment of this species.
A Contribution of the Computer to Biology Education at the University.

ERIC Educational Resources Information Center

Anxolabehere, D.; And Others

1980-01-01

Described is part of the O.P.E. laboratory computer-based biology program designed for undergraduate medical and biology students. Described is an embryology dialogue in which the student proceeds through three stages in the knowledge and understanding of the concept of competence. (Author/DS)
European view of subspecialty training on behalf of the European Society of Human Reproduction and Embryology (ESHRE).

PubMed

Calhaz-Jorge, Carlos; Feki, Anis; Farquharson, Roy

2015-07-01

Specialist training in reproductive medicine within Europe continues to evolve. Recent revisions, updates, and initiatives have helped to refine the core educational needs for the specialist trainee. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
The Theory of Evolution: An Educational Perspective.

ERIC Educational Resources Information Center

Johnson, William L.; Johnson, Annabel M.

The article's thesis is that evolution's intellectual foundations have been steadily eroding, and that few new findings in embryology, taxonomy, fossil remains, and molecular biology are bringing us very near to a formal, logical disproof of Darwinian claims. The paper begins by discussing the evidence of a prehistoric world, then they discuss…
Concluding remarks

NASA Astrophysics Data System (ADS)

Bjørnholm, S.

1991-03-01

Viewing cluster science as the embryology of the full-grown forms of matter we encounter in our surroundings, makes it appear to a relative newcomer as a highly dynamic discipline. Lines of attack showing marked progress or potential promise are briefly reviewed, and a sketch of the vast field of still-open problems is presented.
Computational embryology as an integrative platform for predictive DART (45th Conf of Europ Teratology Society)

EPA Science Inventory

Chemical regulation is challenged by the large number of chemicals requiring assessment for potential human health and environmental impacts. For example, the USEPA lists more than 85,000 chemicals on its inventory of substances that fall under the Toxic Substances Control Act (T...
Source Book of Educational Materials for Diagnostic Medical Ultrasound. Radiological Health Series.

ERIC Educational Resources Information Center

Pijar, Mary Lou, Comp; And Others

This report is a compilation of educational materials that are available in the field of diagnostic medical ultrasound. Materials, which include publications, audiovisual aids, and teaching aids, are listed under the following categories: abdominal imaging; anatomy and physiology; anatomy and embryology; bioeffects; cardiology and vasculature;…
Anatomists Debate the Value of a Teaching Credential

ERIC Educational Resources Information Center

Rizzolo, Lawrence J.; Drake, Richard L.

2008-01-01

Fewer and fewer programs are training graduate students and postdoctoral fellows in the classical anatomical disciplines. Nonetheless, there remains a need at all levels of clinical and basic science education for skilled instructors of anatomy, histology, and embryology. Two sessions at the 2006 annual meeting of the American Association of…
Life Science, A Process Approach, Second Edition: Revised, 1970.

ERIC Educational Resources Information Center

Phare, Wayne; And Others

Seventeen scientific processes are identified and annotated; some suggestions for activities to demonstrate them are given. These processes are used as headings in the teacher's guide to succeeding units on biological classifications, microbiology, physiology of plants and animals, chick embryology and ecology. Similar headings are usually used in…
[Arachnoid cysts: Embriology and pathology].

PubMed

García-Conde, Mario; Martín-Viota, Lucia

2015-01-01

There is still great controversy surrounding the origin of the arachnoid cyst. The most accepted theory in the case of congenital cysts explains how they are formed from an anomalous development of the arachnoid membrane, which is unfolded allowing the accumulation of cerebrospinal fluid inside and creating a cyst. This theory seems to explain the origin of convexity and sylvian cistern arachnoid cysts, whereas those in other locations might be due to other mechanisms. In the anatomopathological analysis, the arachnoid cyst wall can be seen as having few differences from normal, although thickened due to an increase quantity of collagenous material. A description of the embryological development of the arachnoid layer and cyst formation is presented, describing the main anatomopathological findings. Copyright © 2015 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.
Bone Morphogenetic Protein 15 (BMP15) Acts as a BMP and Wnt Inhibitor during Early Embryogenesis*

PubMed Central

Di Pasquale, Elisa; Brivanlou, Ali H.

2009-01-01

Bone morphogenetic protein 15 (BMP15) belongs to an unusual subgroup of the transforming growth factor β (TGFβ) superfamily of signaling ligands as it lacks a key cysteine residue in the mature region required for proper intermolecular dimerization. Naturally occurring BMP15 mutation leads to early ovarian failure in humans, and BMP15 has been shown to activate the Smad1/5/8 pathway in that context. Despite its important role in germ cell specification, the embryological function of BMP15 remains unknown. Surprisingly, we find that during early Xenopus embryogenesis BMP15 acts solely as an inhibitor of the Smad1/5/8 pathway and the Wnt pathway. BMP15 gain-of-function leads to embryos with secondary ectopic heads and to direct neural induction in intact explants. BMP15 inhibits BMP4-mediated epidermal induction in dissociated explants. BMP15 strongly inhibits BRE response induced by BMP4 and blocks phosphorylation and activation of Smad1/5/8 MH2-domain. Mechanistically, BMP15 protein specifically interacts with BMP4 protein, suggesting inhibition upstream of receptor binding. Loss-of-function experiments using morpholinos or a naturally occurring human BMP15 dominant-negative mutant (BMP15-Y235C) leads to embryos lacking head. BMP15-Y235C also eliminates the inhibitory activity of BMP15 on BRE (BMP-responsive element). Finally, we show that BMP15 inhibits the canonical branch of the Wnt pathway, upstream of β-catenin. We, thus, demonstrate that BMP15 is necessary and sufficient for the specification of dorso-anterior structures and highlight novel mechanisms of BMP15 function that strongly suggest a reinterpretation of its function in ovaries specially for ovarian failure. PMID:19553676
[Disorders of sex development and proximal hypospadias].

PubMed

Oswald, J

2016-01-01

Children with ambiguous genitalia due to different chromosome or gonadal sex are a particular challenge concerning the diagnostic and therapeutic implications. Proximal hypospadias patients with normal gonadal development should be distinguished from children with DSD (disorders of sex development) to guarantee normal gender identity and the best possible surgical therapy. This paper focuses on the terminology, embryology, and pathophysiology of the different manifestations of DSD. The state of knowledge about this disease pattern with particular emphasis on proximal hypospadias based on national and international scientific discussions is presented. The different clinical pictures as well as therapeutic options of DSD with a special focus on recent literature and giving particular attention to patients with proximal hypospadias are presented. Because of the complexity of patients suffering from disorders of sex development an interdisciplinary DSD healthcare team including a paediatric endocrinologist as well as paediatric urologist should be provided. These specialists enable an accurate diagnosis in severe hypospadias patients without reference to DSD diseases patterns.

4-H Chickquest: Connecting Agri-Science with STEM Standards in Urban Schools

ERIC Educational Resources Information Center

Horton, Robert L.; Krieger, Jackie; Halasa, Katrina

2013-01-01

While young students are more capable of scientific inquiry than previously believed, elementary school teachers are often inexperienced in and lack confidence with teaching science. ChickQuest is a 4-H-created embryology curriculum for third-graders that meets Ohio state science standards, teaches STEM skills, and promotes ongoing interaction…
The protolobar structure of the human kidney: Its biologic and clinical significance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Inke, G.

This book depicts the uniqueness of each kidney as a result of the interaction of the process of nephronogenesis with the random variability of vascular channels within the bounds of a limited space. The fields of anatomy, developmental biology, comparative morphology, embryology, nephrology, pathology, physiology, radiology, and urologic surgery are treated.
Matter, Motion, and Man, Volume III.

ERIC Educational Resources Information Center

Montag, Betty Jo

Volume Three of the three-volume experimental program in general science attempts to provide preparation for the new approaches in biology, chemistry, and physics and to give those who will not continue in science a realistic way of understanding themselves, the world, and the role of science in society. Chapters on embryology, the body systems,…
Bronchogenic cyst presenting as a symptomatic neck mass in an adult: case report and review of the literature.

PubMed

Al-kasspooles, Mazin F; Alberico, Ronald A; Douglas, Wade G; Litwin, Alan M; Wiseman, Sam M; Rigual, Nestor R; Loree, Thom R; Hicks, Wesley L

2004-12-01

We report the unusual clinical manifestation and subsequent management of a symptomatic congenital bronchogenic cyst that connected to the trachea and presented in the neck of an adult. The embryology, clinical presentation, diagnostic evaluation, and management options of this rare aberration are discussed.
Integration of Gross Anatomy in an Organ System-Based Medical Curriculum: Strategies and Challenges

ERIC Educational Resources Information Center

Brooks, William S.; Woodley, Kristina T. C. Panizzi; Jackson, James R.; Hoesley, Craig J.

2015-01-01

The University of Alabama School of Medicine (UASOM) instituted a fully integrated, organ system-based preclinical curriculum in 2007. Gross anatomy and embryology were integrated with other basic science disciplines throughout the first two years of undergraduate medical education. Here we describe the methods of instruction and integration of…
Medical Education in the Anatomical Sciences: The Winds of Change Continue to Blow

ERIC Educational Resources Information Center

Drake, Richard L.; McBride, Jennifer M.; Lachman, Nirusha; Pawlina, Wojciech

2009-01-01

At most institutions, education in the anatomical sciences has undergone several changes over the last decade. To identify the changes that have occurred in gross anatomy, microscopic anatomy, neuroscience/neuroanatomy, and embryology courses, directors of these courses were asked to respond to a survey with questions pertaining to total course…
Otoplasty: sequencing the operation for improved results.

PubMed

Hoehn, James G; Ashruf, Salman

2005-01-01

: After studying this article, the participant should be able to: 1. Understand the anatomy and embryology of the external ear. 2. Understand the anatomic causes of the prominent ear. 3. Understand the operative maneuvers used to shape the external ear. 4. Be able to sequence the otoplasty for consistent results. 5. Understand the possible complications of the otoplasty procedure. Correction of prominent ears is a common plastic surgical procedure. Proper execution of the surgical techniques is dependent on the surgeon's understanding of the surgical procedure. This understanding is best founded on an understanding of the historical bases for the operative steps and the execution of these operative steps in a logical fashion. This article describes the concept of sequencing the operation of otoplasty to produce predictable results combining the technical contributions from many authors. The historical, embryological, and anatomic bases for the operation are also discussed. Finally, the authors' preferred techniques are presented. Sequencing the steps in the preoperative assessment, preoperative planning, patient management, operative technique, and postoperative care will produce reproducible results for the attentive surgeon. Careful attention to the details of the operation of otoplasty will avoid many postoperative problems.
ETHICS, EMBRYOS, AND EVIDENCE: A LOOK BACK AT WARNOCK.

PubMed

Hammond-Browning, Natasha

2015-01-01

The Report of the Committee of Inquiry into Human Fertilisation and Embryology, the Warnock Report, forms the basis of the UK legislation on embryo research, and its influence continues to be felt, even though over 30 years have passed since its publication. The Warnock Committee was the first of its kind to consider how advancements in human fertilisation and embryology should be regulated. This article examines the evidence submitted to the Warnock Committee, upon which its members ultimately reached their conclusions. With ongoing debate as to the status of the human embryo, it is important to recognise that the legislative position is one that was reached after extensive consultation and consideration of submitted evidence by the Warnock Committee. This article considers the differing ethical viewpoints that were expressed by organisations both prior and post-publication of the Warnock Report, and how the Committee used that evidence to reach their conclusions, and ultimately calls for a new Warnock-style committee. © The Author 2015. Published by Oxford University Press; all rights reserved. For Permissions, please email: journals.permissions@oup.com.
Vestibular morphology in the German Waltzing guinea pig.

PubMed

Kawaguchi, Sachie; Hultcrantz, Malou; Jin, Zhe; Ulfendahl, Mats; Suzuki, Mamoru

2010-04-01

The German waltzing guinea pig is a special strain of animal with a recessively inherited inner ear defect, resulting in deafness and a severe vestibular dysfunction. The hearing loss in the cochlea of the German strain is a result of a collapse of the Reissner membrane and the absence of scala media. The vestibular organ has not yet been described. German waltzing guinea pigs (homozygote and heterozygote) of different ages ranging from embryologic age 25 days to adulthood were investigated. The living animals were tested with four different vestibular tests, and the fetuses were controlled according to breeding. The morphology of the vestibular parts (ampulla, saccule, and utricle) was observed by using the light and transmission electron microscopy. Collapse of the membranous labyrinth was found already at embryologic age 50 days and progressed over time. Vestibular dysfunction was noted already from birth. Vestibular atelectasis has been shown to have the same morphology as the reported vestibular dysfunction in the German waltzing guinea pig. Owing to this similarity, this animal can be a good model for vestibular research.
Experiments and improvements of ear recognition based on local texture descriptors

NASA Astrophysics Data System (ADS)

Benzaoui, Amir; Adjabi, Insaf; Boukrouche, Abdelhani

2017-04-01

The morphology of the human ear presents rich and stable information embedded on the curved 3-D surface and has as a result attracted considerable attention from forensic scientists and engineers as a biometric recognition modality. However, recognizing a person's identity from the morphology of the human ear in unconstrained environments, with insufficient and incomplete training data, strong person-specificity, and high within-range variance, can be very challenging. Following our previous work on ear recognition based on local texture descriptors, we propose to use anatomical and embryological information about the human ear in order to find the autonomous components and the locations where large interindividual variations can be detected. Embryology is particularly relevant to our approach as it provides information on the possible changes that can be observed in the external structure of the ear. We experimented with three publicly available databases, namely: IIT Delhi-1, IIT Delhi-2, and USTB-1, consisting of several ear benchmarks acquired under varying conditions and imaging qualities. The experiments show excellent results, beyond the state of the art.
The ESHRE/ESGE consensus on the classification of female genital tract congenital anomalies.

PubMed

Grimbizis, Grigoris F; Gordts, Stephan; Di Spiezio Sardo, Attilio; Brucker, Sara; De Angelis, Carlo; Gergolet, Marco; Li, Tin-Chiu; Tanos, Vasilios; Brölmann, Hans; Gianaroli, Luca; Campo, Rudi

2013-08-01

What classification system is more suitable for the accurate, clear, simple and related to the clinical management categorization of female genital anomalies? The new ESHRE/ESGE classification system of female genital anomalies is presented. Congenital malformations of the female genital tract are common miscellaneous deviations from normal anatomy with health and reproductive consequences. Until now, three systems have been proposed for their categorization but all of them are associated with serious limitations. The European Society of Human Reproduction and Embryology (ESHRE) and the European Society for Gynaecological Endoscopy (ESGE) have established a common Working Group, under the name CONUTA (CONgenital UTerine Anomalies), with the goal of developing a new updated classification system. A scientific committee (SC) has been appointed to run the project, looking also for consensus within the scientists working in the field. The new system is designed and developed based on (i) scientific research through critical review of current proposals and preparation of an initial proposal for discussion between the experts, (ii) consensus measurement among the experts through the use of the DELPHI procedure and (iii) consensus development by the SC, taking into account the results of the DELPHI procedure and the comments of the experts. Almost 90 participants took part in the process of development of the ESHRE/ESGE classification system, contributing with their structured answers and comments. The ESHRE/ESGE classification system is based on anatomy. Anomalies are classified into the following main classes, expressing uterine anatomical deviations deriving from the same embryological origin: U0, normal uterus; U1, dysmorphic uterus; U2, septate uterus; U3, bicorporeal uterus; U4, hemi-uterus; U5, aplastic uterus; U6, for still unclassified cases. Main classes have been divided into sub-classes expressing anatomical varieties with clinical significance. Cervical and vaginal anomalies are classified independently into sub-classes having clinical significance. The ESHRE/ESGE classification of female genital anomalies seems to fulfill the expectations and the needs of the experts in the field, but its clinical value needs to be proved in everyday practice. The ESHRE/ESGE classification system of female genital anomalies could be used as a starting point for the development of guidelines for their diagnosis and treatment. None.
The Incredible, Embryological Egg: Calcium and Strontium Isotopes Recapitulate Ontogeny

NASA Astrophysics Data System (ADS)

Gordon, G. W.; Skulan, J. L.

2011-12-01

Embryological development reflects evolutionary history. Understanding the processes of fetal growth is important for curing human birth defects and predicting damage to ecosystems from environmental insults. Tracing enzymatic and hormonal gradients during development, and correlating them to genetic cues dominate modern embryology. Previous work done tracing the mass transfer of elements has generally been limited to isotope spikes in vitro. Natural mass-dependent Ca and Sr isotopic ratios and radiogenic Sr isotopes have the potential to reveal both source and biochemical mechanism information about processes in vivo, but have not previously been extensively explored. The process when a hen lays a fertilized egg that becomes a chick includes formation and dissolution of calcium phosphate (bone) and calcium carbonate (shell). Skulan and DePaolo (1999) showed that chickens have 2% δ44/42Ca between a hen's bones and an egg white; this span represents more than 80% of the entire range of natural Ca isotope variation and illustrates there is significant variation to investigate. A striking feature of archosaurian development that also occurs in many mammals, including humans, is mass transfer of calcium from mother to embryo. The yolk of the domestic hen matures over 7-9 days, but the albumen, shell membranes and shell form in less than 20 hours. Domestic laying hens are at the physiological limit of egg production and selective breeding is no longer an effective method of increasing egg production. 60-75% of the shell's ~1.5 g of calcium comes from dietary sources, while 25-40% comes from the hen's medullary bone. Medullary bone is spicules formed in the marrow of long bones, and is a store of dietary calcium rapidly available for eggshell secretion. During in ovo development, the embryo's skeleton is formed from calcium in the yolk and by bulk dissolution of the eggshell's inner aspect via carbonic anhydrase in a process that has an effect on bone density similar to that caused by osteoporosis in humans. For both mass-dependent Ca and Sr isotopes, the isotopic value of the albumen is the highest natural value yet measured. The offset between the δ88/86Sr values of the albumen and shell is 0.45%, less than half that of the δ44/42Ca offset value (1.29%), as predicted by the relative mass differences. However, the yolk is 0.35% heavier than the shell in δ44/42Ca but 0.70% lighter in δ88/86Sr. In addition, the 87Sr/86Sr value of the shell (0.70854 ±0.000012, 2σ) is statistically the same as the albumen (0.70856 ±0.000018), but slightly offset from the yolk (0.70830 ±0.000014). The apparent decoupling of Ca and Sr, and the radiogenic offset between yolk and shell, may reflect differences in the residence time of calcium and strontium in different reproductive organs, as well as the contribution of medullary bone to shell formation. In addition, it may also reflect differential discrimination against Sr versus Ca in oviduct and uterus. Further studies could extend to thinning eggshells in wild avian populations, biochemical mechanisms of bone formation, and the mechanism of strontium ranelate in the treatment of osteoporosis.
Evidence for mixed sexual and asexual reproduction in the rare European mycoheterotrophic orchid Epipogium aphyllum, Orchidaceae (ghost orchid)

PubMed Central

Krawczyk, Emilia; Rojek, Joanna; Kowalkowska, Agnieszka K.; Kapusta, Małgorzata; Znaniecka, Joanna; Minasiewicz, Julita

2016-01-01

Background and Aims Despite their significant capacity to propagate vegetatively, most orchids reproduce via seeds. Sexual reproduction via seed is commonly reported, in contrast to apomixis, whereby seeds are clones of the mother. Although insect pollination and autonomous self-pollination exist in mycoheterotrophic plants, the reproductive embryology of these plants remains under-studied. This paper provides evidence for the co-occurrence of both sexual and apomictic reproduction in a population of mycoheterotrophic plants – Epipogium aphyllum. We investigated seed formation via open pollination, induced autogamy, autogamy sensu stricto and autonomous apomixis. Methods The study was performed on a population of E. aphyllum located in northern Poland. The research included studies of the micromorphology, histochemistry and embryology of four types of reproductive systems. Scanning, fluorescence and light microscopy accompanied by graphical and statistical analyses were employed. Key Results We observed gametophyte development, from the one-nucleate stage to maturity, in unpollinated flower buds. The lack of zygotes in flower buds indicated that fertilization did not occur at this stage. Manual self-pollination led to a zygote, followed by embryo formation. Fertilization and embryo development derived from embryogenesis via open pollination is delayed compared with hand pollination. Isolation from external pollination resulted only in structures resembling zygotes that may originate either sexually or independent of fertilization. Parthenogenetic structures that resembled zygotes were observed in flowers that were emasculated and isolated from pollination. Zygotes formed at significantly higher frequencies via open pollination and induced autogamy in comparison to the parthenogenetic structures formed in other treatments. Conclusions We showed the absence of pre-zygotic barriers for autogamy in E. aphyllum. Self-pollination and self-fertilization are possible; however, natural self-pollination is unlikely or rare due to the position of the pollinia. Incidental parthenogenesis in E. aphyllum is very likely, given the biology of ovule development of this mycoheterotrophic orchid. This species therefore has the potential to produce seeds via both sexual and asexual means, although the contribution of apomixis to this process appears largely negligible. PMID:27288512
Evidence for mixed sexual and asexual reproduction in the rare European mycoheterotrophic orchid Epipogium aphyllum, Orchidaceae (ghost orchid).

PubMed

Krawczyk, Emilia; Rojek, Joanna; Kowalkowska, Agnieszka K; Kapusta, Małgorzata; Znaniecka, Joanna; Minasiewicz, Julita

2016-07-01

Despite their significant capacity to propagate vegetatively, most orchids reproduce via seeds. Sexual reproduction via seed is commonly reported, in contrast to apomixis, whereby seeds are clones of the mother. Although insect pollination and autonomous self-pollination exist in mycoheterotrophic plants, the reproductive embryology of these plants remains under-studied. This paper provides evidence for the co-occurrence of both sexual and apomictic reproduction in a population of mycoheterotrophic plants - Epipogium aphyllum We investigated seed formation via open pollination, induced autogamy, autogamy sensu stricto and autonomous apomixis. The study was performed on a population of E. aphyllum located in northern Poland. The research included studies of the micromorphology, histochemistry and embryology of four types of reproductive systems. Scanning, fluorescence and light microscopy accompanied by graphical and statistical analyses were employed. We observed gametophyte development, from the one-nucleate stage to maturity, in unpollinated flower buds. The lack of zygotes in flower buds indicated that fertilization did not occur at this stage. Manual self-pollination led to a zygote, followed by embryo formation. Fertilization and embryo development derived from embryogenesis via open pollination is delayed compared with hand pollination. Isolation from external pollination resulted only in structures resembling zygotes that may originate either sexually or independent of fertilization. Parthenogenetic structures that resembled zygotes were observed in flowers that were emasculated and isolated from pollination. Zygotes formed at significantly higher frequencies via open pollination and induced autogamy in comparison to the parthenogenetic structures formed in other treatments. We showed the absence of pre-zygotic barriers for autogamy in E. aphyllum Self-pollination and self-fertilization are possible; however, natural self-pollination is unlikely or rare due to the position of the pollinia. Incidental parthenogenesis in E. aphyllum is very likely, given the biology of ovule development of this mycoheterotrophic orchid. This species therefore has the potential to produce seeds via both sexual and asexual means, although the contribution of apomixis to this process appears largely negligible. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Cleft Lip – A Comprehensive Review

PubMed Central

Shkoukani, Mahdi A.; Chen, Michael; Vong, Angela

2013-01-01

Orofacial clefts comprise a range of congenital deformities and are the most common head and neck congenital malformation. Clefting has significant psychological and socio- economic effects on patient quality of life and require a multidisciplinary team approach for management. The complex interplay between genetic and environmental factors play a significant role in the incidence and cause of clefting. In this review, the embryology, classification, epidemiology, and etiology of cleft lip are discussed. The primary goals of surgical repair are to restore normal function, speech development, and facial esthetics. Different techniques are employed based on surgeon expertise and the unique patient presentations. Pre-surgical orthopedics are frequently employed prior to definitive repair to improve outcomes. Long term follow up and quality of life studies are discussed. PMID:24400297
Molecular biology and genetics of embryonic eyelid development.

PubMed

Rubinstein, Tal J; Weber, Adam C; Traboulsi, Elias I

2016-09-01

The embryology of the eyelid is a complex process that includes interactions between the surface ectoderm and mesenchymal tissues. In the mouse and human, the eyelids form and fuse before birth; they open prenatally in the human and postnatally in the mouse. In the mouse, cell migration is stimulated by different growth factors such as FGF10, TGF-α, Activin B, and HB-EGF. These growth factors modulate downstream BMP4 signaling, the ERK cascade, and JNK/c-JUN. Several mechanisms, such as the Wnt/β-catenin signaling pathway, may inhibit and regulate eyelid fusion. Eyelid opening, on the other hand, is driven by the BMP/Smad signaling system. Several human genetic disorders result from dysregulation of the above molecular pathways.
A chicken embryo model for the study of umbilical and supraumbilical body wall malformations.

PubMed

Ridderbusch, Ina; Bergholz, Robert; Fattouh, Miriam; Eschenburg, Georg; Roth, Beate; Appl, Birgit; Maenner, Joerg; Reinshagen, Konrad; Kluth, Dietrich

2015-06-01

BACKGROUND/PURPOSE; The embryology of ventral body wall malformations is only partially understood, although their incidence is relatively common. As only few experimental data exist on the development of those defects, the aim of our study was to compare the teratogenic effect of trypan blue (TB) and suramin (SA) in their capability to induce umbilical and supraumbilical abdominal wall malformations in a chicken egg model. A total of 255 fertilized chicken eggs were incubated at 38 °C and 75% relative humidity. Embryos were treated in ovo on incubation day 2.5 (Hamburger/Hamilton (HH) stage 13). The eggshell was windowed, and solutions of TB or SA were injected into the coelomic cavity at the region of the umbilicus. The window was closed and the embryos reincubated until examination on day 8 (HH 34). A total of 60 embryos survived in each group. The largest number of embryos presented with defects in the umbilical and supraumbilical region (25% in the SA group and 40% in the TB group). A combination of both defects (thoracoabdominoschisis) was seen in 20% of the TB and 8.3% of the SA groups, respectively. Associated anomalies found in both groups were head and eye defects, abnormal pelvic configurations, leg deformities, and mild forms of cloacal exstrophies. TB and SA have both a high potential to induce umbilical and supraumbilical ventral body wall malformations in chicken embryos. This novel animal model might help to establish a more profound understanding of the developmental steps in ventral body wall formation and the embryology for its malformations. Georg Thieme Verlag KG Stuttgart · New York.
Ciona intestinalis: chordate development made simple.

PubMed

Passamaneck, Yale J; Di Gregorio, Anna

2005-05-01

Thanks to their transparent and rapidly developing mosaic embryos, ascidians (or sea squirts) have been a model system for embryological studies for over a century. Recently, ascidians have entered the postgenomic era, with the sequencing of the Ciona intestinalis genome and the accumulation of molecular resources that rival those available for fruit flies and mice. One strength of ascidians as a model system is their close similarity to vertebrates. Literature reporting molecular homologies between vertebrate and ascidian tissues has flourished over the past 15 years, since the first ascidian genes were cloned. However, it should not be forgotten that ascidians diverged from the lineage leading to vertebrates over 500 million years ago. Here, we review the main similarities and differences so far identified, at the molecular level, between ascidian and vertebrate tissues and discuss the evolution of the compact ascidian genome. Copyright 2005 Wiley-Liss, Inc.
A veterinary anatomy tutoring system.

PubMed

Theodoropoulos, G; Loumos, V; Antonopoulos, J

1994-02-14

A veterinary anatomy tutoring system was developed by using Knowledge Pro, an object-oriented software development tool with hypermedia capabilities, and MS Access, a relational database. Communication between them is facilitated by using the Structured Query Language (SQL). The architecture of the system is based on knowledge sets, each of which covers four different descriptions of an organ, namely gross anatomy (general description), gross anatomy (comparative features), histology, and embryology, which constitute the knowledge units. These knowledge units are linked with three global variables that define the animals, the topographies, and the system to which this organ belongs, creating three data-bases. These three data-bases are interrelated through the organ field in order to establish a relational model. This system allows versatility in the student's navigation through the information space by offering different modes for information location and presentation. These include course mode, review mode, reference mode, dissection mode, and comparison mode. In addition, the system provides a self-evaluation mode.
Deep ancestry of programmed genome rearrangement in lampreys.

PubMed

Timoshevskiy, Vladimir A; Lampman, Ralph T; Hess, Jon E; Porter, Laurie L; Smith, Jeramiah J

2017-09-01

In most multicellular organisms, the structure and content of the genome is rigorously maintained over the course of development. However some species have evolved genome biologies that permit, or require, developmentally regulated changes in the physical structure and content of the genome (programmed genome rearrangement: PGR). Relatively few vertebrates are known to undergo PGR, although all agnathans surveyed to date (several hagfish and one lamprey: Petromyzon marinus) show evidence of large scale PGR. To further resolve the ancestry of PGR within vertebrates, we developed probes that allow simultaneous tracking of nearly all sequences eliminated by PGR in P. marinus and a second lamprey species (Entosphenus tridentatus). These comparative analyses reveal conserved subcellular structures (lagging chromatin and micronuclei) associated with PGR and provide the first comparative embryological evidence in support of the idea that PGR represents an ancient and evolutionarily stable strategy for regulating inherent developmental/genetic conflicts between germline and soma. Copyright © 2017 Elsevier Inc. All rights reserved.

Hymenal stenosis and fibrosis in two adult women.

PubMed

Goldstein, Andrew T; Todd, Sarah; Bedell, Sarah; Tabbarah, Abeer

2015-05-01

Hymenal abnormalities are most commonly a result of incomplete apoptosis of the urogenital sinus during embryology. Infrequently, however, noncongenital abnormalities of the hymen can occur that can cause significant sequelae such as severe introital dyspareunia. We report on two adult women who developed severe introital dyspareunia secondary to hymenal stenosis and fibrosis in the absence of other vulvovaginal pathology. Neither woman had point tenderness of the vulvar vestibule, but their symptoms of searing pain on vaginal penetration was reproduced by stretching the hymen with two fingers. In both cases, conservative treatments with vaginal dilators in combination with topical hormonal therapy failed to relieve their symptoms, but both women were subsequently successfully treated with hymenectomy. Hymenal stenosis and fibrosis can develop in the absence of identifiable vulvar dermatoses. If conservative treatment with topical hormonal therapy and vaginal dilators is unsuccessful, hymenectomy can restore normal coital function.
Cardiac Embryology and Molecular Mechanisms of Congenital Heart Disease: A Primer for Anesthesiologists.

PubMed

Kloesel, Benjamin; DiNardo, James A; Body, Simon C

2016-09-01

Congenital heart disease is diagnosed in 0.4% to 5% of live births and presents unique challenges to the pediatric anesthesiologist. Furthermore, advances in surgical management have led to improved survival of those patients, and many adult anesthesiologists now frequently take care of adolescents and adults who have previously undergone surgery to correct or palliate congenital heart lesions. Knowledge of abnormal heart development on the molecular and genetic level extends and improves the anesthesiologist's understanding of congenital heart disease. In this article, we aim to review current knowledge pertaining to genetic alterations and their cellular effects that are involved in the formation of congenital heart defects. Given that congenital heart disease can currently only occasionally be traced to a single genetic mutation, we highlight some of the difficulties that researchers face when trying to identify specific steps in the pathogenetic development of heart lesions.
Production of maternal-zygotic mutant zebrafish by germ-line replacement.

PubMed

Ciruna, Brian; Weidinger, Gilbert; Knaut, Holger; Thisse, Bernard; Thisse, Christine; Raz, Erez; Schier, Alexander F

2002-11-12

We report a generally applicable strategy for transferring zygotic lethal mutations through the zebrafish germ line. By using a morpholino oligonucleotide that blocks primordial germ cell (PGC) development, we generate embryos devoid of endogenous PGCs to serve as hosts for the transplantation of germ cells derived from homozygous mutant donors. Successful transfers are identified by the localization of specifically labeled donor PGCs to the region of the developing gonad in chimeric embryos. This strategy, which results in the complete replacement of the host germ line with donor PGCs, was validated by the generation of maternal and maternal-zygotic mutants for the miles apart locus. This germ-line replacement technique provides a powerful tool for studying the maternal effects of zygotic lethal mutations. Furthermore, the ability to generate large clutches of purely mutant embryos will greatly facilitate embryological, genetic, genomic, and biochemical studies.
Production of maternal-zygotic mutant zebrafish by germ-line replacement

PubMed Central

Ciruna, Brian; Weidinger, Gilbert; Knaut, Holger; Thisse, Bernard; Thisse, Christine; Raz, Erez; Schier, Alexander F.

2002-01-01

We report a generally applicable strategy for transferring zygotic lethal mutations through the zebrafish germ line. By using a morpholino oligonucleotide that blocks primordial germ cell (PGC) development, we generate embryos devoid of endogenous PGCs to serve as hosts for the transplantation of germ cells derived from homozygous mutant donors. Successful transfers are identified by the localization of specifically labeled donor PGCs to the region of the developing gonad in chimeric embryos. This strategy, which results in the complete replacement of the host germ line with donor PGCs, was validated by the generation of maternal and maternal-zygotic mutants for the miles apart locus. This germ-line replacement technique provides a powerful tool for studying the maternal effects of zygotic lethal mutations. Furthermore, the ability to generate large clutches of purely mutant embryos will greatly facilitate embryological, genetic, genomic, and biochemical studies. PMID:12397179
Computer Simulation of Embryonic Systems: What can a virtual embryo teach us about developmental toxicity? (LA Conference on Computational Biology & Bioinformatics)

EPA Science Inventory

This presentation will cover work at EPA under the CSS program for: (1) Virtual Tissue Models built from the known biology of an embryological system and structured to recapitulate key cell signals and responses; (2) running the models with real (in vitro) or synthetic (in silico...
Supernumerary maxillary and Mandibular Fourth Molars.

DTIC Science & Technology

1981-09-23

9-109, 1963. 11. Gorlin, R.J.; Pindborg, J.J.; and Cohen, M.M., Jr.: Syndromes of the Head and Neck , 2nd ed., New York, 1976, McGraw-Hill Book...Hyperdontia:Report of case. JADA 79: 1191-1192, 1969. 5. Sicher, H. (ed.): Orban’s Oral Histology and Embryology , ed. 5, St. Louis, 1962, The C.V. Mosby Co
Modified Use of Team-Based Learning for Effective Delivery of Medical Gross Anatomy and Embryology

ERIC Educational Resources Information Center

Vasan, Nagaswami S.; DeFouw, David O.; Holland, Bart K.

2008-01-01

Team-based learning (TBL) is an instructional strategy that combines independent out-of-class preparation for in-class discussion in small groups. This approach has been successfully adopted by a number of medical educators. This strategy allowed us to eliminate anatomy lectures and incorporate small-group active learning. Although our strategy is…
A review of supernumerary and absent limbs and digits of the upper limb.

PubMed

Klaassen, Zachary; Choi, Monica; Musselman, Ruth; Eapen, Deborah; Tubbs, R Shane; Loukas, Marios

2012-03-01

For years people have been enamored by anomalies of the human limbs, particularly supernumerary and absent limbs and digits. Historically, there are a number of examples of such anomalies, including royal families of ancient Chaldea, tribes from Arabia, and examples from across nineteenth century Europe. The development of the upper limbs in a growing embryo is still being elucidated with the recent advent of homeobox genes, but researchers agree that upper limbs develop between stages 12-23 through a complex embryological process. Maternal thalidomide intake during limb development is known to cause limb reduction and subsequent amelia or phocomelia. Additionally, a number of clinical reports have illustrated different limb anomaly cases, with each situation unique in phenotype and developmental abnormality. Supernumerary and absent limbs and digits are not unique to humans, and a number of animal cases have also been reported. This review of the literature illustrates the historical, anatomical, and clinical aspects of supernumerary and absent limbs and digits for the upper limb.
Creating a histology-embryology free digital image database using high-end microscopy and computer techniques for on-line biomedical education.

PubMed

Silva-Lopes, Victor W; Monteiro-Leal, Luiz H

2003-07-01

The development of new technology and the possibility of fast information delivery by either Internet or Intranet connections are changing education. Microanatomy education depends basically on the correct interpretation of microscopy images by students. Modern microscopes coupled to computers enable the presentation of these images in a digital form by creating image databases. However, the access to this new technology is restricted entirely to those living in cities and towns with an Information Technology (IT) infrastructure. This study describes the creation of a free Internet histology database composed by high-quality images and also presents an inexpensive way to supply it to a greater number of students through Internet/Intranet connections. By using state-of-the-art scientific instruments, we developed a Web page (http://www2.uerj.br/~micron/atlas/atlasenglish/index.htm) that, in association with a multimedia microscopy laboratory, intends to help in the reduction of the IT educational gap between developed and underdeveloped regions. Copyright 2003 Wiley-Liss, Inc.
von Baer's law for the ages: lost and found principles of developmental evolution.

PubMed

Abzhanov, Arhat

2013-12-01

In 1828, Karl Ernst von Baer formulated a series of empirically defined rules, which became widely known as the 'Law of Development' or 'von Baer's law of embryology'. This was one the most significant attempts to define the principles that connected morphological complexity and embryonic development. Understanding this relation is central to both evolutionary biology and developmental genetics. Von Baer's ideas have been both a source of inspiration to generations of biologists and a target of continuous criticism over many years. With advances in multiple fields, including paleontology, cladistics, phylogenetics, genomics, and cell and developmental biology, it is now possible to examine carefully the significance of von Baer's law and its predictions. In this review, I argue that, 185 years after von Baer's law was first formulated, its main concepts after proper refurbishing remain surprisingly relevant in revealing the fundamentals of the evolution-development connection, and suggest that their explanation should become the focus of renewed research. Copyright © 2013 Elsevier Ltd. All rights reserved.
A clinician's personal view of assisted reproductive technology over 35 years.

PubMed

Yovich, John L

2011-12-01

This invited presentation is intended to cover clinical developments in the evolution of assisted reproductive technology (ART), a process which was attempted during the 1940's and 50's and culminated in the first fruition in 1978. The first in vitro fertilisation (IVF) child ensued following the partnership by a scientist with a focussed ambition (Nobel laureate Robert Edwards) joining with the gynaecologist who introduced laparoscopy to Britain in the late 60's (Patrick Steptoe). My journey commenced in 1976 as a clinician who became immersed in the embryological and endocrinological science, whence most progress in ART emanates, and continued into a medical directorship position from which this personal view is documented. Several clinical advances have been important developments in the understanding and management of sub-fertile patients. However evolution of the various laboratory sciences has been the major key essential to meeting both the immediate as well as the long-term needs for human reproduction. The future requires a much better understanding and control over gametogenesis and a laboratory process which much more closely duplicates intrinsic reproductive physiology, avoiding gamete and embryo exposure to the atmosphere.This invited presentation is intended to cover clinical developments in the evolution of assisted reproductive technology (ART), a process which was attempted during the 1940's and 50's and culminated in the first fruition in 1978. The first in vitro fertilisation (IVF) child ensued following the partnership by a scientist with a focussed ambition (Nobel laureate Robert Edwards) joining with the gynaecologist who introduced laparoscopy to Britain in the late 60's (Patrick Steptoe). My journey commenced in 1976 as a clinician who became immersed in the embryological and endocrinological science, whence most progress in ART emanates, and continued into a medical directorship position from which this personal view is documented. Several clinical advances have been important developments in the understanding and management of sub-fertile patients. However evolution of the various laboratory sciences has been the major key essential to meeting both the immediate as well as the long-term needs for human reproduction. The future requires a much better understanding and control over gametogenesis and a laboratory process which much more closely duplicates intrinsic reproductive physiology, avoiding gamete and embryo exposure to the atmosphere.
The Hedgehog-GLI pathway in embryonic development and cancer: implications for pulmonary oncology therapy

PubMed Central

Armas-López, Leonel; Zúñiga, Joaquín; Arrieta, Oscar; Ávila-Moreno, Federico

2017-01-01

Transcriptional regulation and epigenetic mechanisms closely control gene expression through diverse physiological and pathophysiological processes. These include the development of germ layers and post-natal epithelial cell-tissue differentiation, as well as, involved with the induction, promotion and/or progression of human malignancies. Diverse studies have shed light on the molecular similarities and differences involved in the stages of embryological epithelial development and dedifferentiation processes in malignant tumors of epithelial origin, of which many focus on lung carcinomas. In lung cancer, several transcriptional, epigenetic and genetic aberrations have been described to partly arise from environmental risk factors, but ethnic genetic predisposition factors may also play a role. The classification of the molecular hallmarks of cancer has been essential to study and achieve a comprehensive view of the interaction networks between cell signaling pathways and functional roles of the transcriptional and epigenetic regulatory mechanisms. This has in turn increased understanding on how these molecular networks are involved in embryo-layers and malignant diseases development. Ultimately, a major biomedicine goal is to achieve a thorough understanding of their roles as diagnostic, prognostic and treatment response indicators in lung oncological patients. Recently, several notable cell-signaling pathways have been studied based on their contribution to promoting and/or regulating the engagement of different cancer hallmarks, among them genome instability, exacerbated proliferative signaling, replicative immortality, tumor invasion-metastasis, inflammation, and immune-surveillance evasion mechanisms. Of these, the Hedgehog-GLI (Hh) cell-signaling pathway has been identified as a main molecular contribution into several of the abovementioned functional embryo-malignancy processes. Nonetheless, the systematic study of the regulatory epigenetic and transcriptional mechanisms has remained mostly unexplored, which could identify the interaction networks between specific biomarkers and/or new therapeutic targets in malignant tumor progression and resistance to lung oncologic therapy. In the present work, we aimed to revise the most important up-to-date experimental and clinical findings in biology, embryology and cancer research regarding the Hh pathway. We explore the potential control of the transcriptional-epigenetic programming versus reprogramming mechanisms associated with its Hh-GLI cell signaling pathway members. Last, we present a summary of this information to systematically integrate the Hh signaling pathway to identify and propose novel compound strategies or better oncological therapeutic schemes for lung cancer patients. PMID:28948003
Midline cervical cleft: a rare congenital anomaly.

PubMed

Renukaswamy, Gayathri Mandya; Soma, Marlene A; Hartley, Benjamin E J

2009-11-01

A midline cervical cleft (MCC) is a rare congenital anomaly due to failure of fusion of the first and second branchial arches during embryogenesis. It may present as a midline defect of the anterior neck skin with a skin projection or sinus, or as a subcutaneous fibrous cord. This report evaluates the clinical features and surgical management of an MCC. We analyzed a series of 4 patients with an MCC successfully treated at Great Ormond Street Hospital for Children in London. Three male patients and 1 female patient between 4 and 11 months of age were found to have an MCC. Each patient presented with an erythematous, fibrous band of tissue extending between the chin and the suprasternal notch. Treatment comprised surgical excision of the lesion and Z-plasty repair. We present the embryology, common clinical presentation, investigations, differential diagnosis, and histology, along with a literature review, of this uncommon malformation of the anterior neck. An MCC is a differential diagnosis to consider when assessing a child with a midline cervical lesion. Early surgical excision with Z-plasty repair of the soft tissue defect is the treatment of choice to prevent long-term complications.
A Marble Embryo: Meanings of a Portrait from 1900

PubMed Central

Hopwood, Nick

2012-01-01

Portraits of scientists use attributes of discovery to construct identities; portraits that include esoteric accessories may fashion identities for these too. A striking example is a marble bust of the anatomist Wilhelm His by the Leipzig sculptor Carl Seffner. Made in 1900, it depicts the founder of modern human embryology looking down at a model embryo in his right hand. This essay reconstructs the design and viewing of this remarkable portrait in order to shed light on private and public relations between scientists, research objects and audiences. The bust came out of a collaboration to model the face of the composer Johann Sebastian Bach and embodies a shared commitment to anatomical exactitude in three dimensions. His’s research agendas and public character explain the contemplative pose and unprecedented embryo model, which he had laboriously constructed from material a midwife supplied. The early contexts of display in the His home and art exhibitions suggest interpretive resources for viewers and hence likely meanings. Seffner’s work remains exceptional, but has affinities to portraits of human embryologists and embryos produced since 1960. Embryo images have acquired such controversial prominence that the model may engage us more strongly now than it did exhibition visitors around 1900. PMID:22606754
Charles Darwin and the Origins of Plant Evolutionary Developmental Biology

PubMed Central

Friedman, William E.; Diggle, Pamela K.

2011-01-01

Much has been written of the early history of comparative embryology and its influence on the emergence of an evolutionary developmental perspective. However, this literature, which dates back nearly a century, has been focused on metazoans, without acknowledgment of the contributions of comparative plant morphologists to the creation of a developmental view of biodiversity. We trace the origin of comparative plant developmental morphology from its inception in the eighteenth century works of Wolff and Goethe, through the mid nineteenth century discoveries of the general principles of leaf and floral organ morphogenesis. Much like the stimulus that von Baer provided as a nonevolutionary comparative embryologist to the creation of an evolutionary developmental view of animals, the comparative developmental studies of plant morphologists were the basis for the first articulation of the concept that plant (namely floral) evolution results from successive modifications of ontogeny. Perhaps most surprisingly, we show that the first person to carefully read and internalize the remarkable advances in the understanding of plant morphogenesis in the 1840s and 1850s is none other than Charles Darwin, whose notebooks, correspondence, and (then) unpublished manuscripts clearly demonstrate that he had discovered the developmental basis for the evolutionary transformation of plant form. PMID:21515816
Charles Darwin and the origins of plant evolutionary developmental biology.

PubMed

Friedman, William E; Diggle, Pamela K

2011-04-01

Much has been written of the early history of comparative embryology and its influence on the emergence of an evolutionary developmental perspective. However, this literature, which dates back nearly a century, has been focused on metazoans, without acknowledgment of the contributions of comparative plant morphologists to the creation of a developmental view of biodiversity. We trace the origin of comparative plant developmental morphology from its inception in the eighteenth century works of Wolff and Goethe, through the mid nineteenth century discoveries of the general principles of leaf and floral organ morphogenesis. Much like the stimulus that von Baer provided as a nonevolutionary comparative embryologist to the creation of an evolutionary developmental view of animals, the comparative developmental studies of plant morphologists were the basis for the first articulation of the concept that plant (namely floral) evolution results from successive modifications of ontogeny. Perhaps most surprisingly, we show that the first person to carefully read and internalize the remarkable advances in the understanding of plant morphogenesis in the 1840s and 1850s is none other than Charles Darwin, whose notebooks, correspondence, and (then) unpublished manuscripts clearly demonstrate that he had discovered the developmental basis for the evolutionary transformation of plant form.
[Comparison of human chorionic gonadotropin (Pregnyl 10 000 IU i.m.) versus GnRH agonist (triptorelin 0,2 mg s.c.) for final oocytes maturation in the same egg donors--clinical and embryological characteristics].

PubMed

Streda, R; Mardesic, T; Sobotka, V; Koryntová, D; Hybnerová, L; Jindra, M; Paseková, V; Slámová, J; Stevíková, M; Voboril, J; Jelínková, L; Vilímová, S; Ichová, J; Mádrová, J; Tersová, H; Masata, M; Sobotková, J

2011-04-01

To compare clinical and embryological characteristics in donor cycles triggered for final oocytes maturation with Pregnyl 10 000 IU i.m. versus triptorelin 0.2 mg s.c. in the same patients in two sequential stimulation cycles. The aim of the study is to decrease the risk of the development of ovarian hyperstimulation syndrome (OHSS) at high response donors by the replacement of Pregnyl 10 000 IU i.m. vs. triptorelin 0.2 mg s.c. The administration of a single dose of gonadotropin-releasing hormone agonist (triptorelin 0.2 mg s.c.) induces release of LH from the pituitary gland similarly to a spontaneous LH surge. Prospective cross-over trial. Sanatorium Pronatal, Praha. From August 2009 to July 2010 we analysed 24 stimulation cycles in 12 egg donors treated with GnRH antagonist protocol with recombinant FSH (follitropin beta). We identified patients with more than 15 follicles during examination by transvaginal ultrasound. When at least 3 leading follicles reached 17 mm in diameter we administrated Pregnyl 10 000 IU i.m. for final oocytes maturation and triptorelin 0.2 mg s.c in the subsequent treatment cycle. The primary outcome measure was number of oocytes, proportion mature oocytes and fertilized oocytes. The secondary outcome were duration of FSH stimulation, total dose of gonadotropins and mean daily dose of gonadotropins. Data was analysed by paired t-test. We retrieved 17.2 +/- 8.6 vs. 15.8 +/- 5.3 (ns) oocytes, 12.6 +/- 7.3 vs. 13.0 +/- 5.4 (ns) metaphase II oocytes, proportion of metaphase II oocytes (%) was 73 vs. 83 (ns), number of fertilized oocytes 11.5 +/- 6.7 vs. 11.7 +/- 4.5 (ns), fertilization rate (%) 91 vs. 90 (ns) in Pregnyl's vs. triptorelin's group, resp. Duration of FSH stimulation (days) 12.2 +/- 0.8 vs. 12.4 +/- 0.7 (ns), total dose of gonadotropins (IU) 1744 +/- 277 vs. 1740 +/- 276 (ns), mean daily dose of gonadotropins (IU) 238 +/- 43 vs. 221 +/- 36 (ns), were not statistically different in both groups. Number of mature oocytes and subsequent embryonic cleavage is comparable to standard hCG treatment. There are no differences in clinical and embryological characteristics in both groups. Only one patient with administration of Pregnyl 10 000 IU i.m. was treated for OHSS grade II by vaginal paracentesis. Administration of triptorelin 0.2 mg s.c. is a safe and effective approach to achieve mature oocytes in egg donation programme, where we do not take care of implantation, which has got some limitations based on several studies.
Clefting of the Alveolus: Emphasizing the Distinction from Cleft Palate.

PubMed

Wirtz, Nicholas; Sidman, James; Block, William

2016-05-01

Oral clefting is one of the most common significant fetal abnormalities. Cleft lip and cleft palate have drastically different clinical ramifications and management from one another. A cleft of the alveolus (with or without cleft lip) can confuse the diagnostic picture and lead to a false assumption of cleft palate. The cleft alveolus should be viewed on the spectrum of cleft lip rather than be associated with cleft palate. This is made evident by understanding the embryological development of the midface and relevant terminology. Cleft alveolus carries significantly different clinical implications and treatment options than that of cleft palate. Accurately distinguishing cleft alveolus from cleft palate is crucial for appropriate discussions regarding the patient's care. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
Fetus-in-Fetu: An Unusual Cause for Abdominal Mass in Infancy

PubMed Central

Grosfeld, Jay L.; Stepita, Donald S.; Nance, Walter E.; Palmer, Catherine G.

1974-01-01

Fetus-in-fetu is an unusual cause of retroperitoneal abdominal mass in infants, which most likely arises from inclusion of a monozygotic, diamniotic twin. This entity is distinguished from teratoma by its embryological origin, its unusual location in the retroperitoneal space, its invariable benignity, and by the presence of vertebral organization with limb buds and well-developed organ systems. Diagnosis is made radiographically by the finding of a diminutive vertebral column on a plain abdominal film. The treatment of choice is total excision with special attention being given to the fetus' blood supply which may be directly from the host's superior mesenteric vessels. A well-documented example of this unusual entity that occurred in a six-week old infant male is presented. ImagesFig. 1.Fig. 2.Fig. 3. PMID:4471720
Deconstructing Pancreas Developmental Biology

PubMed Central

Benitez, Cecil M.; Goodyer, William R.

2012-01-01

The relentless nature and increasing prevalence of human pancreatic diseases, in particular, diabetes mellitus and adenocarcinoma, has motivated further understanding of pancreas organogenesis. The pancreas is a multifunctional organ whose epithelial cells govern a diversity of physiologically vital endocrine and exocrine functions. The mechanisms governing the birth, differentiation, morphogenesis, growth, maturation, and maintenance of the endocrine and exocrine components in the pancreas have been discovered recently with increasing tempo. This includes recent studies unveiling mechanisms permitting unexpected flexibility in the developmental potential of immature and mature pancreatic cell subsets, including the ability to interconvert fates. In this article, we describe how classical cell biology, genetic analysis, lineage tracing, and embryological investigations are being complemented by powerful modern methods including epigenetic analysis, time-lapse imaging, and flow cytometry-based cell purification to dissect fundamental processes of pancreas development. PMID:22587935

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