scholarly journals The role of invasive trophoblast in implantation and placentation of primates

2015 ◽  
Vol 370 (1663) ◽  
pp. 20140070 ◽  
Author(s):  
Anthony M. Carter ◽  
Allen C. Enders ◽  
Robert Pijnenborg
Keyword(s):  
Basal Lamina ◽  
Common Ancestor ◽  
Great Apes ◽  
Blastocyst Stage ◽  
Trophoblast Invasion ◽  
Deep Penetration ◽  
Old World Monkeys ◽  
Non Invasive ◽  
The Common

We here review the evolution of invasive placentation in primates towards the deep penetration of the endometrium and its arteries in hominoids. The strepsirrhine primates (lemurs and lorises) have non-invasive, epitheliochorial placentation, although this is thought to be derived from a more invasive type. In haplorhine primates, there is differentiation of trophoblast at the blastocyst stage into syncytial and cellular trophoblast. Implantation involves syncytiotrophoblast that first removes the uterine epithelium then consolidates at the basal lamina before continuing into the stroma. In later stages of pregnancy, especially in Old World monkeys and apes, cytotrophoblast plays a greater role in the invasive process. Columns of trophoblast cells advance to the base of the implantation site where they spread out to form a cytotrophoblastic shell. In addition, cytotrophoblasts advance into the lumen of the spiral arteries. They are responsible for remodelling these vessels to form wide, low-resistance conduits. In human and great apes, there is additional invasion of the endometrium and its vessels by trophoblasts originating from the base of the anchoring villi. Deep trophoblast invasion that extends remodelling of the spiral arteries to segments in the inner myometrium evolved in the common ancestor of gorilla, chimp and human.

scholarly journals Role of the Digestive Gland in Ink Production in Four Species of Sea Hares: An Ultrastructural Comparison

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Jeffrey S. Prince ◽  
Paul Micah Johnson
Keyword(s):  
Digestive Gland ◽  
Common Ancestor ◽  
Aplysia Californica ◽  
Digestive Cell ◽  
Digestive Cells ◽  
Sea Hare ◽  
Red Algal ◽  
The Common ◽  
Algal Chloroplast

The ultrastructure of the digestive gland of several sea hare species that produce different colored ink (Aplysia californicaproduces purple ink,A. julianawhite ink,A. parvulaboth white and purple ink, whileDolabrifera dolabriferaproduces no ink at all) was compared to determine the digestive gland’s role in the diet-derived ink production process. Rhodoplast digestive cells and their digestive vacuoles, the site of digestion of red algal chloroplast (i.e., rhodoplast) inA. californica, were present and had a similar ultrastructure in all four species. Rhodoplast digestive cell vacuoles either contained a whole rhodoplast or fragments of one or were empty. These results suggest that the inability to produce colored ink in some sea hare species is not due to either an absence of appropriate digestive machinery, that is, rhodoplast digestive cells, or an apparent failure of rhodoplast digestive cells to function. These results also propose that the digestive gland structure described herein occurred early in sea hare evolution, at least in the common ancestor to the generaAplysiaandDolabrifera. Our data, however, do not support the hypothesis that the loss of purple inking is a synapomorphy of the white-ink-producing subgenusAplysia.

scholarly journals Presence of three mycorrhizal genes in the common ancestor of land plants suggests a key role of mycorrhizas in the colonization of land by plants

2010 ◽  
Vol 186 (2) ◽  
pp. 514-525 ◽  
Author(s):  
Bin Wang ◽  
Li Huey Yeun ◽  
Jia-Yu Xue ◽  
Yang Liu ◽  
Jean-Michel Ané ◽  
...  
Keyword(s):  
Common Ancestor ◽  
Land Plants ◽  
The Common ◽  
Colonization Of Land

scholarly journals A study of host defence peptide β-defensin 3 in primates

2003 ◽  
Vol 374 (3) ◽  
pp. 707-714 ◽  
Author(s):  
Michele BONIOTTO ◽  
Nikolinka ANTCHEVA ◽  
Igor ZELEZETSKY ◽  
Alessandro TOSSI ◽  
Valeria PALUMBO ◽  
...  
Keyword(s):  
Biological Activity ◽  
Amino Acid ◽  
Salt Bridge ◽  
Great Apes ◽  
Primate Species ◽  
Old World Monkeys ◽  
Functional Implication ◽  
Gene Coding ◽  
Microbial Action

We have investigated the molecular evolution of the gene coding for β-defensin 3 (DEFB103) in 17 primate species including humans. Unlike the DEFB4 genes (coding for β-defensin 2) [Boniotto, Tossi, Del Pero, Sgubin, Antcheva, Santon and Masters (2003) Genes Immun. 4, 251–257], DEFB103 shows a marked degree of conservation in humans, Great Apes and New and Old World monkeys. Only the Hylobates concolor defensin hcBD3 showed an amino acid variation Arg17→Trp17 that could have a functional implication, as it disrupts an intramolecular salt bridge with Glu27, which locally decreases the charge and may favour dimerization in the human congener hBD3. This is thought to involve the formation of an intermolecular salt bridge between Glu28 and Lys32 on another monomer [Schibli, Hunter, Aseyev, Starner, Wiencek, McCray, Tack and Vogel (2002) J. Biol. Chem. 277, 8279–8289]. To test the role of dimerization in mediating biological activity, we synthesized hBD3, hcBD3 and an artificial peptide in which the Lys26-Glu27-Glu28 stretch was replaced by the equivalent Phe-Thr-Lys stretch from human β-defensin 1 and we characterized their structure and anti-microbial activity. Although the structuring and dimerization of these peptides were found to differ significantly, this did not appear to affect markedly the anti-microbial potency, the broad spectrum of activity or the insensitivity of the anti-microbial action to the salinity of the medium.

scholarly journals β-Catenin–dependent mechanotransduction dates back to the common ancestor of Cnidaria and Bilateria

2018 ◽  
Vol 115 (24) ◽  
pp. 6231-6236 ◽  
Author(s):  
Ekaterina Pukhlyakova ◽  
Andrew J. Aman ◽  
Kareem Elsayad ◽  
Ulrich Technau
Keyword(s):  
Gene Expression ◽  
Common Ancestor ◽  
Marker Gene ◽  
Genetic Regulation ◽  
Regulation Of Gene Expression ◽  
Model Organism ◽  
The Common ◽  
Gene Regulatory ◽  
Ancient Gene

Although the genetic regulation of cellular differentiation processes is well established, recent studies have revealed the role of mechanotransduction on a variety of biological processes, including regulation of gene expression. However, it remains unclear how universal and widespread mechanotransduction is in embryonic development of animals. Here, we investigate mechanosensitive gene expression during gastrulation of the starlet sea anemone Nematostella vectensis, a cnidarian model organism. We show that the blastoporal marker gene brachyury is down-regulated by blocking myosin II-dependent gastrulation movements. Brachyury expression can be restored by applying external mechanical force. Using CRISPR/Cas9 and morpholino antisense technology, we also show that mechanotransduction leading to brachyury expression is β-catenin dependent, similar to recent findings in fish and Drosophila [Brunet T, et al. (2013) Nat Commun 4:1–15]. Finally, we demonstrate that prolonged application of mechanical stress on the embryo leads to ectopic brachyury expression. Thus, our data indicate that β-catenin–dependent mechanotransduction is an ancient gene regulatory mechanism, which was present in the common ancestor of cnidarians and bilaterians, at least 600 million years ago.

scholarly journals Unique Aspects of Human Placentation

2021 ◽  
Vol 22 (15) ◽  
pp. 8099
Author(s):  
Anthony M. Carter
Keyword(s):  
Common Ancestor ◽  
Placental Lactogen ◽  
Extravillous Trophoblast ◽  
Trophoblast Invasion ◽  
Placental Lactogens ◽  
Intervillous Space ◽  
Cretaceous Period ◽  
Precise Role ◽  
Extended Parental Care

Human placentation differs from that of other mammals. A suite of characteristics is shared with haplorrhine primates, including early development of the embryonic membranes and placental hormones such as chorionic gonadotrophin and placental lactogen. A comparable architecture of the intervillous space is found only in Old World monkeys and apes. The routes of trophoblast invasion and the precise role of extravillous trophoblast in uterine artery transformation is similar in chimpanzee and gorilla. Extended parental care is shared with the great apes, and though human babies are rather helpless at birth, they are well developed (precocial) in other respects. Primates and rodents last shared a common ancestor in the Cretaceous period, and their placentation has evolved independently for some 80 million years. This is reflected in many aspects of their placentation. Some apparent resemblances such as interstitial implantation and placental lactogens are the result of convergent evolution. For rodent models such as the mouse, the differences are compounded by short gestations leading to the delivery of poorly developed (altricial) young.

scholarly journals The arboreal origins of human bipedalism

Antiquity ◽  
2014 ◽  
Vol 88 (341) ◽  
pp. 906-914 ◽  
Author(s):  
Susannah K.S. Thorpe ◽  
Juliet M. McClymont ◽  
Robin H. Crompton
Keyword(s):  
Recent Work ◽  
Charles Darwin ◽  
Common Ancestor ◽  
Great Apes ◽  
Human Lineage ◽  
Terrestrial Species ◽  
The Common ◽  
Key Features ◽  
Descent Of Man

Almost a century and a half ago, Charles Darwin inThe Descent of Man(1871: 141) highlighted the evolution of bipedalism as one of the key features of the human lineage, freeing the hands for carrying and for using and making tools. But how did it arise? The famous footprints from Laetoli in Tanzania show that hominin ancestors were walking upright by at least 3.65 million years ago. Recent work, however, suggests a much earlier origin for bipedalism, in a Miocene primate ancestor that was still predominantly tree-dwelling. Here Susannah Thorpe, Juliet McClymont and Robin Crompton set out the evidence for that hypothesis and reject the notion that the common ancestor of great apes and humans was a knuckle-walking terrestrial species, as are gorillas and chimpanzees today. The article is followed by a series of comments, rounded off by a reply from the authors.

scholarly journals The Evolution of the Role of Imaging in the Diagnosis of Craniosynostosis: A Narrative Review

Children ◽  
2021 ◽  
Vol 8 (9) ◽  
pp. 727
Author(s):  
Giovanni Cacciaguerra ◽  
Monica Palermo ◽  
Lidia Marino ◽  
Filippo Andrea Salvatore Rapisarda ◽  
Piero Pavone ◽  
...  
Keyword(s):  
Imaging Techniques ◽  
Correct Choice ◽  
Therapeutic Interventions ◽  
Know How ◽  
Non Invasive ◽  
The Past ◽  
Precise Diagnosis ◽  
The Common ◽  
Technological Limitations

Craniosynostosis, the premature closure of cranial sutures, is one of the principal causes of pediatric skull deformities. It can cause aesthetic, neurological, acoustic, ophthalmological complications up to real emergencies. Craniosynostosis are primarily diagnosed with accurate physical examination, skull measurement and observation of the deformity, but the radiological support currently plays an increasingly important role in confirming a more precise diagnosis and better planning for therapeutic interventions. The clinician must know how to diagnose in the earliest and least invasive way for the child. In the past, technological limitations reduced the choices; today, however, there are plenty of choices and it is necessary to use the various types of available imaging correctly. In the future, imaging techniques will probably rewrite the common classifications we use today. We provide an updated review of the role of imaging in this condition, through the ages, to outline the correct choice for the clinician for an early and non-invasive diagnosis.

The Utility of Non-invasive Tests for Detection of Previous Proximal-vein Thrombosis

1995 ◽  
Vol 73 (04) ◽  
pp. 592-596 ◽  
Author(s):  
Sabina Villalta ◽  
Paolo Prandoni ◽  
Alberto Cogo ◽  
Paola Bagatella ◽  
Andrea Piccioli ◽  
...  
Keyword(s):  
Clinical Evaluation ◽  
Femoral Vein ◽  
Clinical Score ◽  
Diagnostic Methods ◽  
Popliteal Vein ◽  
Venous Reflux ◽  
Study Objective ◽  
Vein Thrombosis ◽  
Non Invasive ◽  
The Common

SummaryBackground. Despite the availability of several diagnostic methods for the detection of deep-vein thrombosis (DVT), the identification of previous episodes of DVT remains a diagnostic challenge.Study objective. To assess the reliability of a combination of a standardized clinical score with three non-invasive tests: compression ultrasonography (CUS), Doppler ultrasound (DUS), and photoplethysmography (PPG), in determining the presence or the absence of previous proximal DVT.Methods. One hundred consecutive unselected outpatients were identified, who had undergone contrast venography six to nine years previously because of the clinical suspicion of DVT (confirmed in 43). They were blindly reinvestigated by a panel of trained operators unaware of venography results. They underwent a clinical evaluation of the lower limb, by applying a standardized score to five symptoms and six signs (grading each item from 0 to 3); a PPG test to determine the venous refilling time; a DUS test to determine the venous reflux separately in the common femoral and the popliteal vein; and a CUS test to determine vein compressibility in the same regions.Results. An abnormal CUS test and/or the demonstration of venous reflux in the popliteal region and/or a high clinical score (≥ 8) identified twenty-four of the 43 (56%) DVT + patients with a specificity of 89%. The combination of normal CUS with the absence of venous reflux in both the common femoral and popliteal vein and a low clinical score excluded previous thrombosis in 45 (79%) of the 57 DVT- patients (negative predictive value, 78%). Abnormal venous reflux in the isolated common femoral vein did not reliably predict the presence or absence of previous DVT. However, this occurred in only 13 (13%) patients. The PPG determination of venous refilling time did not improve the results obtained with the other tests.Conclusions. The combination of a standardized clinical evaluation with the results of CUS and DUS can reliably diagnose or exclude previous proximal-vein thrombosis in almost 90% of patients with previous episodes of suspected DVT.

On everyday academic research

2017 ◽  
pp. 98-134 ◽  
Author(s):  
J. Tirole
Keyword(s):  
Common Good ◽  
Academic Research ◽  
Research Quality ◽  
Economic Research ◽  
Relevant Research ◽  
The Common ◽  
Verification Of Models ◽  
Science And Research

In the fourth chapter of the book “The economy of the common good”, the nature of economics as a science and research practices in their theoretical and empirical aspects are discussed. The author considers the processes of modeling, empirical verification of models and evaluation of research quality. In addition, the features of economic cognition and the role of mathematics in economic research are analyzed, including the example of relevant research in game theory and information theory.

Sign in / Sign up

Export Citation Format

Share Document