scholarly journals Immunocytochemical studies of cardiac myofibrillogenesis in early chick embryos. III. Generation of fasciae adherentes and costameres.

1989 ◽  
Vol 108 (1) ◽  
pp. 43-53 ◽  
Author(s):  
K T Tokuyasu
Keyword(s):  
Cell Membranes ◽  
Spatial Information ◽  
De Novo ◽  
Three Dimensional ◽  
Myocardial Cell ◽  
Double Labeling ◽  
Rhodamine Phalloidin ◽  
Somite Stage ◽  
Myocardial Wall ◽  
Cell Layers

To study whether the first myofibrils are separate from or firmly bound to the myocytic cell membranes, whole mount preparations of 6-12-somite-stage chick embryonic hearts were examined by fluorescence microscopy after double labeling with antibodies to vinculin (fluorescein-conjugated) and rhodamine-phalloidin, or with antibodies to titin (rhodamine-conjugated) and nitrobenz-oxadiazole-phallacidin. When a small number of myofibrils appeared for the first time at the nine somite stage, most of them were already bound to the cell membranes through zonulae adherentes, fasciae adherentes, or costameres. In the outer of the two myocardial cell layers, in which the myocytes were closely in contact with each other along polygonal boundaries, fasciae adherentes and costameres developed at the boundaries, apparently by conversion of preexisting zonulae adherentes. On the other hand, in the inner cell layer, in which myocytes were more loosely associated with each other, both costameres and fasciae adherentes appeared to develop de novo, the former in association with the inner surface of the myocardial wall and the latter at the intercellular boundaries. The myofibrillar tracks in the inner layer followed long and smooth courses and were as a whole aligned in the circumferential direction of the tubular heart wall from the earliest stage of myofibril formation. Those in the outer layer were arranged in a pattern of two- or three-dimensional networks in the 9-10 somite stage, although many myofibrils were also circumferentially directed. The fact that the majority of the first myofibrils were already bound to the cell membranes in a directed manner suggests that myocytes at the earliest stage of myofibril formation are endowed with spatial information that directs the organization of nascent myofibrils. It is proposed that the myocyte cell membranes perform an essential role in cardiac myofibrillogenesis.

scholarly journals Immunocytochemical studies of cardiac myofibrillogenesis in early chick embryos. I. Presence of immunofluorescent titin spots in premyofibril stages.

1987 ◽  
Vol 105 (6) ◽  
pp. 2781-2793 ◽  
Author(s):  
K T Tokuyasu ◽  
P A Maher
Keyword(s):  
Scaffolding Protein ◽  
Chick Embryos ◽  
Resolution Limit ◽  
Somite Stage ◽  
Myocardial Wall ◽  
Nonionic Detergent ◽  
Cell Layers ◽  
Detergent Treatment ◽  
Uniform Labeling

Our initial attempts to immunolabel intact myocardial walls of 4-12 somite stage chick embryos were hindered by the presence of the cardiac jelly that covers the inner myocardial wall surface and prevents the access of antibodies to that surface. We overcame this difficulty by treating the specimens with hyaluronidase, which made the cardiac jelly permeable to the antibodies. An additional nonionic detergent treatment made the two or more cell layers of the myocardial wall accessible to the antibodies from both surfaces of the wall. Specimens treated in this manner were fluorescently labeled with antibodies to titin, myosin, or actin or with NBD-phallacidin for F-actin and examined as whole mount preparations or cut into semithin sections after resin embedding. These preparations and sections revealed that titin, a putative scaffolding protein of sarcomeres, is present in a punctate state and also in a diffuse form throughout the cytoplasm of cardiac myocytes in the premyofibril stages (4-7 somite stages) as well as in the early stages of myofibril formation. We interpreted the punctate and diffuse states to represent an aggregated state of several titin molecules and a dispersed state of individual titin molecules, respectively. In the 4-7 somite cardiac primodia, myosin and actin show only a uniform labeling throughout the cytoplasm of the myocytes. These observations are in contrast to a previous report that titin and myosin are tightly linked during in vitro skeletal myofibrillogenesis (Hill, C. S., S. Duran, Z. Ling, K. Weber, and H. Holtzer, 1986, J. Cell Biol., 103:2185-2196). In the 8-11 somite stage hearts, the number of individual titin spots rapidly reduces, while the number of myofibrils with periodically aligned titin spots increases, which strongly suggests that the titin spots are incorporated into the newly arising myofibrils. Titin spots were seen as doublets only after titin spots were incorporated into the first myofibrils. However, the fact that the distance between the components of the narrowest doublet was close to the resolution limit of the light microscope left open the possibility that undiscernible doublets of submicroscopic separations might exist in the premyofibril stages. The myosin labeling revealed the sarcomeric periodicity in an earlier stage of myofibril development than the F-actin labeling. In addition, we made two morphogenic observations.(ABSTRACT TRUNCATED AT 400 WORDS)

Melatonin actions in the heart; more than a hormone

2018 ◽  
Vol 1 (1) ◽  
pp. 21-26 ◽  
Author(s):  
Darío Acuña-Castroviejo ◽  
Maria T Noguiera-Navarro ◽  
Russel J Reiter ◽  
Germaine Escames
Keyword(s):  
Cell Membranes ◽  
Myocardial Cell ◽  
Rat Tissues ◽  
Dependent Manner ◽  
Broad Distribution ◽  
Multiple Organs ◽  
High Doses ◽  
Extrapineal Melatonin ◽  
Dose Dependent ◽  
Different Doses

Due to the broad distribution of extrapineal melatonin in multiple organs and tissues, we analyzed the presence and subcellular distribution of the indoleamine in the heart of rats. Groups of sham-operated and pinealectomized rats were sacrificed at different times along the day, and the melatonin content in myocardial cell membranes, cytosol, nuclei and mitochondria, were measured. Other groups of control animals were treated with different doses of melatonin to monitor its intracellular distribution. The results show that melatonin levels in the cell membrane, cytosol, nucleus, and mitochondria vary along the day, without showing a circadian rhythm. Pinealectomized animals trend to show higher values than sham-operated rats. Exogenous administration of melatonin yields its accumulation in a dose-dependent manner in all subcellular compartments analyzed, with maximal concentrations found in cell membranes at doses of 200 mg/kg bw melatonin. Interestingly, at dose of 40 mg/kg b.w, maximal concentration of melatonin was reached in the nucleus and mitochondrion. The results confirm previous data in other rat tissues including liver and brain, and support that melatonin is not uniformly distributed in the cell, whereas high doses of melatonin may be required for therapeutic purposes.

scholarly journals Virtual Archaeology of Death and Burial: A Procedure for Integrating 3D Visualization and Analysis in Archaeothanatology

2021 ◽  
Vol 7 (1) ◽  
pp. 540-555
Author(s):  
Hayley L. Mickleburgh ◽  
Liv Nilsson Stutz ◽  
Harry Fokkens
Keyword(s):  
Spatial Information ◽  
3D Visualization ◽  
Rapid Development ◽  
Three Dimensional ◽  
3D Models ◽  
The Body ◽  
Test Case ◽  
Archaeology Of Death ◽  
Human Burials ◽  
3D Information

Abstract The reconstruction of past mortuary rituals and practices increasingly incorporates analysis of the taphonomic history of the grave and buried body, using the framework provided by archaeothanatology. Archaeothanatological analysis relies on interpretation of the three-dimensional (3D) relationship of bones within the grave and traditionally depends on elaborate written descriptions and two-dimensional (2D) images of the remains during excavation to capture this spatial information. With the rapid development of inexpensive 3D tools, digital replicas (3D models) are now commonly available to preserve 3D information on human burials during excavation. A procedure developed using a test case to enhance archaeothanatological analysis and improve post-excavation analysis of human burials is described. Beyond preservation of static spatial information, 3D visualization techniques can be used in archaeothanatology to reconstruct the spatial displacement of bones over time, from deposition of the body to excavation of the skeletonized remains. The purpose of the procedure is to produce 3D simulations to visualize and test archaeothanatological hypotheses, thereby augmenting traditional archaeothanatological analysis. We illustrate our approach with the reconstruction of mortuary practices and burial taphonomy of a Bell Beaker burial from the site of Oostwoud-Tuithoorn, West-Frisia, the Netherlands. This case study was selected as the test case because of its relatively complete context information. The test case shows the potential for application of the procedure to older 2D field documentation, even when the amount and detail of documentation is less than ideal.

Free and conjugated polyamines during de novo floral and vegetative bud formation in thin cell layers of tobacco

1987 ◽  
Vol 70 (3) ◽  
pp. 453-460 ◽  
Author(s):  
Patrizia Torrigiani ◽  
Maria Maddalena Altamura ◽  
Gabriella Pasqua ◽  
Barbara Monacelli ◽  
Donatella Serafini-Fracassini ◽  
...  
Keyword(s):  
De Novo ◽  
Bud Formation ◽  
Thin Cell Layers ◽  
Conjugated Polyamines ◽  
Cell Layers ◽  
Free And Conjugated Polyamines ◽  
Vegetative Bud

Navigating in a volumetric world: Metric encoding in the vertical axis of space

2013 ◽  
Vol 36 (5) ◽  
pp. 546-547 ◽  
Author(s):  
Theresa Burt de Perera ◽  
Robert Holbrook ◽  
Victoria Davis ◽  
Alex Kacelnik ◽  
Tim Guilford
Keyword(s):  
Spatial Information ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Vertical Component ◽  
Vertical Axis ◽  
Orthogonal Axis ◽  
Experimental Protocols ◽  
Three Dimensional Space ◽  
The Way

AbstractAnimals navigate through three-dimensional environments, but we argue that the way they encode three-dimensional spatial information is shaped by how they use the vertical component of space. We agree with Jeffery et al. that the representation of three-dimensional space in vertebrates is probably bicoded (with separation of the plane of locomotion and its orthogonal axis), but we believe that their suggestion that the vertical axis is stored “contextually” (that is, not containing distance or direction metrics usable for novel computations) is unlikely, and as yet unsupported. We describe potential experimental protocols that could clarify these differences in opinion empirically.

Current view of the yesterday's medicine (review)

2021 ◽  
Vol 9-10 (219-220) ◽  
pp. 44-51
Author(s):  
Abay Zhangabylov ◽  
◽  
Bakytzhan Bimbetov ◽  
Nurlan Jainakbayev ◽  
Каramyat Zordinova ◽  
...  
Keyword(s):  
Liver Diseases ◽  
Literature Search ◽  
Cell Membranes ◽  
De Novo ◽  
Genetic System ◽  
Evidence Base ◽  
Biological Species ◽  
Current View ◽  
Native Form ◽  
Essential Phospholipids

Phospholipids (PL) – lipids that are not involved in accumulation of fatty deposits play a significant role and serve various functions. Firstly, as a component of cell membranes of all cells in the organism. In clinical practice, for the past decades, phospholipids were primarily used as hepaprotective substances, going by the name of “essential phospholipids (EPL)”. Becoming a popular, demanded, well-promoted remedy for the treatment of liver diseases. However, despite the many years of approbation, the existing and sufficientclinicalexperience, discussions regarding their benefits, effectiveness, safety and reliability are still underway and have brought up diametrically opposed views. From complete rejection of EPL as medicinal means, to full recognition of the advertised properties of EPL drugs based on the given manufacturer’s descriptions. For this reason, to clarify the issuing situation, we have conducted a literature search on the object of investigation. Purpose of the study. Search and critical analysis of modern literature sources on the topic of work using the principles of evidence-based medicine. Material and Methods. A critical online review of the literature sources chosen for the research has been carried out in the Web of Science Thompson Reuters, Springer Link and Pubmed databases, as well as in research works and online articles 10 years deep. Inclusion criteria: research papers with a high index of evidence base. Exclusion criteria: literature sources with no evidence, low quality works. Results and Discussion. The articleoutlines the natural role of proteins, lipids and the function of the cytolemma of intracellularorganoids in the restoration of damaged membranes of hepatocytes - de novo. Substantiating the obvious uselessness of using essential phospholipids in the treatment of liver diseases in general, fatty hepatosis in particular. The inability of penetration into liver cells for phospholipids in their native form and their alignment in thehepacyte membrane is indicated, since they belong to different biological species and have a mutually closed genetic system. In the literature search undertaken by us on this issue, the analytical and critical review of scientific literature have also shown that when ingested, essential phospholipids have low bioavailability, as the phospholipids in the chylomicrons do not directly enter the liver, but first the lymphatic system through which they are transported to the adipose tissue of the organism, where they are accumulated and metabolized. With parenteral administration, EPL spreading through the bloodstream can accumulate in other organs, systems, without reaching the liver tissue. For example, the largest amounts of EPL are usually found in the cell membranes of the nervous tissue and the brain. Conclusion. Essential phospholipids in the form of soy lecithin products cannot replace the endogenous phospholipids of the human body - in principle. Keywords: essentialphospholipids, liver cell membranes, hepaprotectors.

scholarly journals A three-dimensional culture model of innervated human skeletal muscle enables studies of the adult neuromuscular junction and disease modeling

2018 ◽  
Author(s):  
Mohsen Afshar Bakooshli ◽  
Ethan S Lippmann ◽  
Ben Mulcahy ◽  
Nisha R Iyer ◽  
Christine T Nguyen ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Neuromuscular Junction ◽  
Motor Neuron ◽  
Motor Neurons ◽  
Human Skeletal Muscle ◽  
Disease Modeling ◽  
De Novo ◽  
Muscle Fibers ◽  
Three Dimensional ◽  
Adult Human

SummaryTwo-dimensional (2D) human skeletal muscle fiber cultures are ill equipped to support the contractile properties of maturing muscle fibers. This limits their application to the study of adult human neuromuscular junction (NMJ) development, a process requiring maturation of muscle fibers in the presence of motor neuron endplates. Here we describe a three-dimensional (3D) co-culture method whereby human muscle progenitors mixed with human pluripotent stem cell-derived motor neurons self-organize to form functional NMJ connections within two weeks. Functional connectivity between motor neuron endplates and muscle fibers is confirmed with calcium transient imaging and electrophysiological recordings. Notably, we only observed epsilon acetylcholine receptor subunit protein upregulation and activity in 3D co-culture. This demonstrates that the 3D co-culture system supports a developmental shift from the embryonic to adult form of the receptor that does not occur in 2D co-culture. Further, 3D co-culture treatments with myasthenia gravis patient sera shows the ease of studying human disease with the system. This work delivers a simple, reproducible, and adaptable method to model and evaluate adult human NMJ de novo development and disease in culture.

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