scholarly journals The desmosomal cadherin Desmogon is necessary for the structural integrity of the Medaka notochord

2019 ◽  
Author(s):  
Ali Seleit ◽  
Karen Gross ◽  
Michaela Woelk ◽  
Camilla Autorino ◽  
Jasmin Onistschenko ◽  
...  
Keyword(s):  
Structural Integrity ◽  
Cell Formation ◽  
Cell Types ◽  
Small Scale ◽  
Outer Sheath ◽  
Notochord Cell ◽  
Crispr Screen ◽  
Vacuolated Cell ◽  
Vacuolated Cells ◽  
Early Developmental

AbstractThe notochord is an embryonic tissue that acts as a precursor to the spine. It is composed of outer sheath cells and inner vacuolated cells. Together they ensure the ability of the notochord to act as a hydrostatic skeleton until ossification begins. To date, there is still a paucity in our understanding of how the notochord cell types are specified and the molecular players controlling both their formation and maintenance remain poorly understood. Here we report that desmogon, a desmosomal cadherin, is essential for proper vacuolated cell shape and therefore correct notochord morphology. We trace desmogon+ precursors and uncover an early developmental heterogeneity that dictates the balance of vacuolated and sheath cell formation. We demonstrate that the growth of vacuolated cells occurs asynchronously and reveal the presence of distinct injury sensing mechanisms in the notochord. Additionally, using a small-scale F0 CRISPR screen we implicate uncharacterized genes in notochordal integrity.

Epididymal Interstitial (Leydig) Cell Tumors in B6C3F1 Mice

1989 ◽  
Vol 26 (1) ◽  
pp. 65-69 ◽  
Author(s):  
K. Mitsumori ◽  
F. A. Talley ◽  
M. R. Elwell
Keyword(s):  
Leydig Cell ◽  
Testicular Tumor ◽  
Cell Types ◽  
Brown Pigment ◽  
Eosinophilic Cytoplasm ◽  
Vacuolated Cell ◽  
B6c3f1 Mice ◽  
Large Round ◽  
Vacuolated Cells ◽  
Vacuolated Cytoplasm

Six primary interstitial cell tumors of the epididymis were identified from 46,752 male B6C3F1 mice used in chronic toxicity and carcinogenicity studies. Five of the tumors occurred at the end of 2-year studies; none were attributed to treatment. None of the mice with epididymal tumors had a primary testicular tumor. Histologically, tumors were characterized by a nodular or diffuse proliferation of tumor cells in the epididymal interstitium. Most cells were polygonal with highly vacuolated cytoplasm (vacuolated cells) or eosinophilic cytoplasm (eosinophilic cells). Smaller hyperchromatic cells with scant basophilic cytoplasm (basophilic cells) and cells with yellow-brown pigment characteristic of lipofuscin (pigmented cells) were less common. In each tumor two or more cell types were present. Extension of these tumors through the capsule, invasion of the testis, or metastasis did not occur. By electron microscopy both eosinophilic and vacuolated cell types had a large round or oval nucleus with sparse heterochromatin, abundant mitochondria with tubulovesicular cristae, and frequent desmosome structures between cell membranes. Vacuolated cells contained numerous lipid droplets. Morphological features of the epididymal tumors are similar to those of the testicular interstitial (Leydig) cell tumor in mice and rats.

The Morphology of Vacuolated Cells in the Liver Following Administration of Vitamin A.

1973 ◽  
Vol 31 ◽  
pp. 408-409
Author(s):  
Odell T. Minick ◽  
Hidejiro Yokoo ◽  
Fawzia Batti
Keyword(s):  
Electron Microscopy ◽  
Body Weight ◽  
Vitamin A ◽  
Light And Electron Microscopy ◽  
Liver Cells ◽  
Prominent Feature ◽  
Vascular Space ◽  
Vacuolated Cell ◽  
Vacuolated Cells ◽  
Vacuolated Cytoplasm

Vacuolated cells in the liver of young rats were studied by light and electron microscopy following the administration of vitamin A (200 units per gram of body weight). Their characteristics were compared with similar cells found in untreated animals.In rats given vitamin A, cells with vacuolated cytoplasm were a prominent feature. These cells were found mostly in a perisinusoidal location, although some appeared to be in between liver cells (Fig. 1). Electron microscopy confirmed their location in Disse's space adjacent to the sinusoid and in recesses between liver cells. Some appeared to be bordering the lumen of the sinusoid, but careful observation usually revealed a tenuous endothelial process separating the vacuolated cell from the vascular space. In appropriate sections, fenestrations in the thin endothelial processes were noted (Fig. 2, arrow).

The Florey Lecture, 1988 - From egg to embryo: the initiation of cell differentiation in Amphibia

1989 ◽  
Vol 237 (1286) ◽  
pp. 11-25 ◽  
Keyword(s):  
Muscle Cell ◽  
Gene Activation ◽  
Cell Formation ◽  
Gene Promoter ◽  
Cell Types ◽  
Specific Gene ◽  
Embryonic Induction ◽  
Differentiated Cells ◽  
Wide Range ◽  
Muscle Genes

Some of the principles by which different cell types first arise at the beginning of animal development are illustrated by muscle cell formation in Amphibia. If the nucleus of a differentiated muscle cell is transplanted to an enucleated egg, some of the resulting embryos develop into tadpoles with a wide range of normally differentiated cells. These experiments show that genes undergo major changes in activity as a response to components of egg cytoplasm. Two fundamental mechanisms account for the regional activation of genes in early embryos. One involves the effect of localized ‘determinants’ in egg cytoplasm, and the other concerns cell interactions or embryonic induction. Both these mechanisms seem to be responsible for muscle cell formation in amphibian development. The old problem of embryonic induction has recently become accessible to analysis at the molecular level, especially in the case of the mesoderm or muscle-forming induction. This has been greatly facilitated by using a sensitive and quantitative assay to detect the first transcripts of muscle genes a few hours after the start of induction. The role of early events and of interactions among like cells during response to induction is discussed. In analysing specific gene activation following induction, DNA injection into fertilized eggs has shown that a very small part of the cardiac actin gene promoter is sufficient to enable it to respond to induction. Although the experimental work summarized here has been done on amphibian embryos, which are more suitable than other embryos for embryological manipulation, the conclusions reached are believed to be generally applicable to the development of other organisms.

scholarly journals Mapping calcium dynamics in a developing tubular structure

2020 ◽  
Author(s):  
Jorgen Hoyer ◽  
Morsal Saba ◽  
Daniel Dondorp ◽  
Kushal Kolar ◽  
Riccardo Esposito ◽  
...  
Keyword(s):  
Cell Types ◽  
Feedback Mechanism ◽  
Adult Brain ◽  
Actin Dynamics ◽  
Cytoskeletal Network ◽  
Notochord Cell ◽  
Wide Range ◽  
Store Operated Calcium Entry ◽  
And Function ◽  
Cell Intercalation

AbstractCalcium is a ubiquitous and versatile second messenger that plays a central role in the development and function of a wide range of cell types, tissues and organs. Despite significant recent progress in the understanding of calcium (Ca2+) signalling in organs such as the developing and adult brain, we have relatively little knowledge of the contribution of Ca2+ to the development of tubes, structures widely present in multicellular organisms. Here we image Ca2+ dynamics in the developing notochord of Ciona intestinalis. We show that notochord cells exhibit distinct Ca2+ dynamics during specific morphogenetic events such as cell intercalation, cell elongation and tubulogenesis. We used an optogenetically controlled Ca2+ actuator to show that sequestration of Ca2+ results in defective notochord cell intercalation, and pharmacological inhibition to reveal that stretch-activated ion channels (SACs), inositol triphosphate receptor (IP3R) signalling, Store Operated Calcium Entry (SOCE), Sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) and gap junctions are required for regulating notochord Ca2+ activity during tubulogenesis. Cytoskeletal rearrangements drive the cell shape changes that accompany tubulogenesis. In line with this, we show that Ca2+ signalling modulates reorganization of the cytoskeletal network across the morphogenetic events leading up to and during tubulogenesis of the notochord. We additionally demonstrate that perturbation of the actin cytoskeleton drastically remodels Ca2+ dynamics, suggesting a feedback mechanism between actin dynamics and Ca2+ signalling during notochord development. This work provides a framework to quantitatively define how Ca2+ signalling regulates tubulogenesis using the notochord as model organ, a defining structure of all chordates.

scholarly journals Characterisation of GLUT4 trafficking in HeLa cells: comparable kinetics and orthologous trafficking mechanisms to 3T3-L1 adipocytes

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8751 ◽  
Author(s):  
Silke Morris ◽  
Niall D. Geoghegan ◽  
Jessica B.A. Sadler ◽  
Anna M. Koester ◽  
Hannah L. Black ◽  
...  
Keyword(s):  
Cell Surface ◽  
Hela Cells ◽  
Glucose Transporter ◽  
Characteristic Property ◽  
Cell Types ◽  
Model System ◽  
Human Model ◽  
Small Scale ◽  
Glucose Transporter Glut4 ◽  
Surface Fusion

Insulin-stimulated glucose transport is a characteristic property of adipocytes and muscle cells and involves the regulated delivery of glucose transporter (GLUT4)-containing vesicles from intracellular stores to the cell surface. Fusion of these vesicles results in increased numbers of GLUT4 molecules at the cell surface. In an attempt to overcome some of the limitations associated with both primary and cultured adipocytes, we expressed an epitope- and GFP-tagged version of GLUT4 (HA–GLUT4–GFP) in HeLa cells. Here we report the characterisation of this system compared to 3T3-L1 adipocytes. We show that insulin promotes translocation of HA–GLUT4–GFP to the surface of both cell types with similar kinetics using orthologous trafficking machinery. While the magnitude of the insulin-stimulated translocation of GLUT4 is smaller than mouse 3T3-L1 adipocytes, HeLa cells offer a useful, experimentally tractable, human model system. Here, we exemplify their utility through a small-scale siRNA screen to identify GOSR1 and YKT6 as potential novel regulators of GLUT4 trafficking in human cells.

scholarly journals Multiplexed 3D atlas of state transitions and immune interactions in colorectal cancer

2021 ◽  
Author(s):  
Jia-Ren Lin ◽  
Shu Wang ◽  
Shannon Coy ◽  
Madison A Tyler ◽  
Clarence Yapp ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Prognostic Significance ◽  
Tissue Microarrays ◽  
Cell Types ◽  
Tissue Imaging ◽  
State Transitions ◽  
Small Scale ◽  
Spatial Gradients ◽  
Immunosuppressive Cell ◽  
Small Fields

Advanced solid cancers are complex assemblies of tumor, immune, and stromal cells that invade adjacent tissue and spread to distant sites. Here we use highly multiplexed tissue imaging, spatial statistics, and machine learning to identify cell types and states underlying morphological features of known diagnostic and prognostic significance in colorectal cancer. We find that a thorough spatial analysis requires imaging the entire tumor region, not small fields of view (e.g. those found in tissue microarrays). When this condition is met, the data reveal frequent transitions between histological archetypes (tumor grades and morphologies) correlated with molecular gradients. At the tumor invasive margin, where tumor, normal, and immune cells compete, localized features in 2D such as tumor buds and mucin pools are seen in 3D to be large connected structures having continuously varying molecular properties. Immunosuppressive cell-cell interactions also exhibit graded variation in type and frequency. Thus, whereas scRNA-Seq emphasizes discrete changes in tumor state, whole-specimen imaging reveals the presence of large- and small-scale spatial gradients analogous to those in developing tissues.

Offloading Operability of Small Scale AG FLNG With Side-by-Side Moored Small Scale LNG Carrier in Offshore West Africa

2017 ◽  
Author(s):  
Mun-sung Kim ◽  
Eric Morilhat ◽  
X. C. Nguyen ◽  
Bo-hee Kim ◽  
Jung-moon Jang ◽  
...  
Keyword(s):  
West Africa ◽  
Relative Motion ◽  
Structural Integrity ◽  
Effective Means ◽  
Production Capacity ◽  
Cost Effective ◽  
Body Motion ◽  
Small Scale ◽  
Associated Gas ◽  
High Level

This study describes one of the technical solutions for Small Scale FLNG (SSFLNG)[1] development specifically designed to monetize Associated Gas (AG) of producing oil fields located within convenient distance of an existing LNG Plant or Port with LNG storage facility. Limited production capacity combined with short range small scale LNG carriers (SSLNGC), provide a cost effective means for LNG production. Ship to ship off-loading operation by loading arm has been considered in AG SSFLNG. Produced LNG is to be off-loaded from the SSFLNG to side-by-side moored SSLNGC. Relative motion and dynamic load acting on loading arm system in side-by-side mooring arrangement is one of key factors to estimate the offloading operability of the AG SSFLNG. In this paper, a numerical two-body motion analysis for the side-by-side moored SSFLNG in frequency- and time-domain is carried out. Also, the basic engineering work is carried out for the marine loading arms (MLA). Since the MLA reacts approximately as a linear system, it is calculated by a full spectral RAO analysis for each of the worst load cases issued from the spectral ranking. All loads and stresses inside the MLA are verified in accordance with EN1474-1[2] for the situations identified in the previous step. A high level fatigue analysis focused on the cryogenic swivel joints is carried out. Based on the numerical calculation for relative motion in side-by-side moored FLNG, we have been performed structural assessment for MLA in several environment conditions. The structural integrity of both MLA and the LNGC manifold are validated during offloading for Offshore West Africa.

Four Points Bending Tests on Large Scale Welded Pipes Containing a Through-Wall Defect: Fatigue and Fracture Analysis

2014 ◽  
Author(s):  
M. Bourgeois ◽  
T. Le Grasse ◽  
Y. Kayser
Keyword(s):  
Large Scale ◽  
Structural Integrity ◽  
Atomic Energy Commission ◽  
Electrical Potential ◽  
Potential Drop ◽  
Small Scale ◽  
Butt Weld ◽  
Bending Tests ◽  
Scale Test ◽  
Fracture Tests

Within the framework of European project STYLE (Structural integrity for lifetime management), fracture tests on two large scale pipes containing a through wall crack have been performed. Two Mock-ups have been tested: MU1 is a narrow gap Inconel Dissimilar Metals, provided and designed by AREVA France, and MU2 is a an austenitic steel butt-weld with a thermally aged weld repair austenitic weld, provided by EDF British Energy. The four-points bending tests were carried out by the French Alternative Energies and Atomic Energy Commission (CEA), in order to study the mechanical properties and integrity of component such as welding pipes. A through wall crack was machined in the both pipes. After a fatigue pre-cracking step carried out at RT, the monotonic fracture test was performed (at 300°C on MU1). Optical camera and Electrical Potential Drop Method have allowed following the crack growth during fatigue and final fracture stages. The observations made post-mortem showed ductile tearing of a few millimeters in those pipes. The first part of this paper is devoted to the four-points bending tests. The second part of this paper deals with first numerical analysis related to the Mock-up-1. Previous results concerning the mechanical characterizations of the constitutive materials are discussed. Fracture mechanics small scale specimens are interpreted using FE Analysis to obtain the fracture parameters used in global approaches. First computation is shown on the Mock-up-1 in order to predict the behavior of the large scale test mechanical and fracture behavior.

Neuropsychologist, Psychologist, 3 years’ experience, USA

2020 ◽  
pp. 59-62
Author(s):  
Markus Reuber ◽  
Gregg H. Rawlings ◽  
Steven C. Schachter
Keyword(s):  
Large Scale ◽  
Structural Integrity ◽  
Small Scale ◽  
Brain Functioning ◽  
Clear Explanation ◽  
Neurological Problem ◽  
Psychological Origin ◽  
The Brain ◽  
Connection Problems ◽  
Clinical Domain

This chapter examines how, when treating individuals with Psychogenic Non-Epileptic Events (PNEE), a neuropsychologist operates from a viewpoint of PNEE as a “psycho-neurological” problem. The distinction between a “neurological” and “psychological” origin has important implications for the training necessary to perform the services offered by each specialist, but both specialties actually refer to the same origin of the PNEE. In both cases PNEE clearly arise from the brain. The neuropsychologist views these spheres not as separate and distinct, but rather as being on a continuous spectrum, with the major difference being the scale and scope at which the brain is considered. Neurological problems are typically viewed as large scale, concretely identifiable, and dealing with fundamental functioning and structural integrity. Psychological problems are viewed as small-scale neurological connection problems, too granular for the primary attention of neurologists. This is the clinical domain of psychiatrists, psychologists, and neuropsychologists. PNEE clearly have their origins in the brain, falling within the sphere of small-scale connection problems of brain functioning. Finally this chapter considers the lack of a clear explanation for why and how PNEE manifest in the brain because their true origin remains elusive.

scholarly journals A Fresh Look at the Structure, Regulation, and Functions of Fodrin

2020 ◽  
Vol 40 (17) ◽  
Author(s):  
Jamuna S. Sreeja ◽  
Rince John ◽  
Dhrishya Dharmapal ◽  
Rohith Kumar Nellikka ◽  
Suparna Sengupta
Keyword(s):  
Posttranslational Modifications ◽  
Mammalian Cells ◽  
Structural Integrity ◽  
Cell Function ◽  
Cell Types ◽  
Erythroid Cell ◽  
Structural Variations ◽  
Neuronal Tissues ◽  
Different Cell Types ◽  
Neuronal Disorders

ABSTRACT Fodrin and its erythroid cell-specific isoform spectrin are actin-associated fibrous proteins that play crucial roles in the maintenance of structural integrity in mammalian cells, which is necessary for proper cell function. Normal cell morphology is altered in diseases such as various cancers and certain neuronal disorders. Fodrin and spectrin are two-chain (αβ) molecules that are encoded by paralogous genes and share many features but also demonstrate certain differences. Fodrin (in humans, typically a heterodimer of the products of the SPTAN1 and SPTBN1 genes) is expressed in nearly all cell types and is especially abundant in neuronal tissues, whereas spectrin (in humans, a heterodimer of the products of the SPTA1 and SPTB1 genes) is expressed almost exclusively in erythrocytes. To fulfill a role in such a variety of different cell types, it was anticipated that fodrin would need to be a more versatile scaffold than spectrin. Indeed, as summarized here, domains unique to fodrin and its regulation by Ca2+, calmodulin, and a variety of posttranslational modifications (PTMs) endow fodrin with additional specific functions. However, how fodrin structural variations and misregulated PTMs may contribute to the etiology of various cancers and neurodegenerative diseases needs to be further investigated.

Sign in / Sign up

Export Citation Format

Share Document