Inorganic Polyphosphates As Storage for and Generator of Metabolic Energy in the Extracellular Matrix

Investigating the regulation of very late antigen (VLA)-mediated functions, we found that TS2/16, a mAb directed against the beta chain of the VLA group of integrins, can induce binding of resting peripheral blood lymphocytes, cloned T lymphocytes, and Epstein Barr virus-transformed B cells to extracellular matrix components, fibronectin, laminin, and collagen, but not to fibrinogen. The antibody stimulates VLA-4-, VLA-5-, and VLA-6-mediated binding. Furthermore, it induces VLA-4-mediated binding to vascular cell adhesion molecule-1 expressed by rTNF-alpha-stimulated endothelial cells, but it does not stimulate homotypic aggregation of cells as described for a number of anti-VLA-4 alpha antibodies (Bednarczyk, J.L., and B. W. McIntyre. 1990. J. Immunol. 144: 777-784; Campanero, M. R., R. Pulido, M. A. Ursa, M. Rodríguez-Moya, M. O. de Landázuri, and F. Sánchez-Madrid. 1990. J. Cell Biol. 110:2157-2165). Therefore, the stimulating activity of this anti-beta 1 antibody clearly contrasts with that of the anti-VLA-4 alpha antibodies, which induce homotypic cell aggregation, but not binding of cells to extracellular matrix components or endothelial cells, indicating that TS2/16 may generate different signals. The observation that also F(ab')2 or Fab fragments of this anti-beta 1 antibody stimulate binding to extracellular matrix components and endothelial cells excludes the possibility that binding requires receptor crosslinking, or is Fc receptor mediated. Induction of this adhesion is cation and energy dependent and requires an intact cytoskeleton. Although changes in the conformation of VLA integrins induced by this antibody may regulate their functional activity, the dependence on metabolic energy indicates that intracellular processes may also play a role.

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Cardiac myocytes cultured on a basement membrane extract of the ehs tumor

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142979 ◽

1986 ◽

Vol 44 ◽

pp. 270-271

Author(s):

L. Terracio ◽

A. Dewey ◽

K. Rubin ◽

T.K. Borg

Keyword(s):

Extracellular Matrix ◽

Basement Membrane ◽

Cardiac Myocytes ◽

Normal Tissue ◽

Cell Spreading ◽

Collagen Iv ◽

Basement Membrane Extract ◽

Membrane Extract ◽

Growth Development ◽

Multicellular Organisms

The recognition and interaction of cells with the extracellular matrix (ECM) effects the normal physiology as well as the pathology of all multicellular organisms. These interactions have been shown to influence the growth, development, and maintenance of normal tissue function. In previous studies, we have shown that neonatal cardiac myocytes specifically interacts with a variety of ECM components including fibronectin, laminin, and collagens I, III and IV. Culturing neonatal myocytes on laminin and collagen IV induces an increased rate of both cell spreading and sarcomerogenesis.

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Neutrophil migration through in vitro interstitial matrix

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124872 ◽

1992 ◽

Vol 50 (1) ◽

pp. 894-895

Author(s):

J. Roemer ◽

S.R. Simon

Keyword(s):

Extracellular Matrix ◽

Smooth Muscle ◽

Cell Migration ◽

Smooth Muscle Cells ◽

Inflammatory Cell ◽

Neutrophil Migration ◽

Culture Conditions ◽

Aortic Smooth Muscle ◽

Specific Culture

We are developing an in vitro interstitial extracellular matrix (ECM) system for study of inflammatory cell migration. Falcon brand Cyclopore membrane inserts of various pore sizes are used as a support substrate for production of ECM by R22 rat aortic smooth muscle cells. Under specific culture conditions these cells produce a highly insoluble matrix consisting of typical interstitial ECM components, i.e.: types I and III collagen, elastin, proteoglycans and fibronectin.

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Electron microscope study of the effects of radiation on insect fertility

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100157905 ◽

1990 ◽

Vol 48 (3) ◽

pp. 72-73

Author(s):

Judy Ju-Hu Chiang ◽

Robert Kuo-Cheng Chen

Keyword(s):

Electron Microscopy ◽

Germ Cell ◽

Germ Cells ◽

Electron Microscope Study ◽

Radiation Treatment ◽

Light And Electron Microscopy ◽

Stem Borer ◽

Metabolic Energy ◽

Rice Stem Borer ◽

Effects Of Radiation

Germ cells from the rice stem borer Chilo suppresalis, were examined by light and electron microscopy. Damages to organelles within the germ cells were observed. The mitochondria, which provide the cell with metabolic energy, were seen to disintegrate within the germ cell. Lysosomes within the germ cell were also seen to disintegrate. The subsequent release of hydrolytic enzymesmay be responsible for the destruction of organelles within the germ cell. Insect spermatozoa were seen to lose the ability to move because of radiation treatment. Damage to the centrioles, one of which is in contact with the tail, may be involved in causing sperm immobility.

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The extracellular matrix of echinoderm and amphibian eggs: Visualization in quick-frozen, deep-etched, and rotary-shadowed specimens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015784x ◽

1990 ◽

Vol 48 (3) ◽

pp. 60-61

Author(s):

Barry Bonnell ◽

Carolyn Larabell ◽

Douglas Chandler

Keyword(s):

Extracellular Matrix ◽

Plasma Membrane ◽

Sea Urchin ◽

Crystalline Structure ◽

Cortical Granule ◽

Two Dimensional ◽

Small Peptides ◽

Deep Etching ◽

Quick Freezing ◽

Acrosomal Reaction

Eggs of many species including those of echinoderms, amphibians and mammals exhibit an extensive extracellular matrix (ECM) that is important both in the reception of sperm and in providing a block to polyspermy after fertilization.In sea urchin eggs there are two distinctive coats, the vitelline layer which contains glycoprotein sperm receptors and the jelly layer that contains fucose sulfate glycoconjugates which trigger the acrosomal reaction and small peptides which act as chemoattractants for sperm. The vitelline layer (VL), as visualized by quick-freezing, deep-etching, and rotary-shadowing (QFDE-RS), is a fishnet-like structure, anchored to the plasma membrane by short posts. Orbiting above the VL are horizontal filaments which are thought to anchor the thicker jelly layer to the egg. Upon fertilization, the VL elevates and is transformed by cortical granule secretions into the fertilization envelope (FE). The rounded casts of microvilli in the VL are transformed into angular peaks and the envelope becomes coated inside and out with sheets of paracrystalline protein having a quasi-two dimensional crystalline structure.

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The limits of human performance

Essays in Biochemistry ◽

10.1042/bse0440011 ◽

2008 ◽

Vol 44 ◽

pp. 11-26 ◽

Cited By ~ 14

Author(s):

Ralph Beneke ◽

Dieter Böning

Keyword(s):

Human Performance ◽

Safety Margin ◽

Afferent Input ◽

Metabolic Energy ◽

Human Organism ◽

Mechanical Resistance ◽

As Doping ◽

Gene And Protein Expression ◽

Underlying Mechanisms ◽

Biochemical Research

Human performance, defined by mechanical resistance and distance per time, includes human, task and environmental factors, all interrelated. It requires metabolic energy provided by anaerobic and aerobic metabolic energy sources. These sources have specific limitations in the capacity and rate to provide re-phosphorylation energy, which determines individual ratios of aerobic and anaerobic metabolic power and their sustainability. In healthy athletes, limits to provide and utilize metabolic energy are multifactorial, carefully matched and include a safety margin imposed in order to protect the integrity of the human organism under maximal effort. Perception of afferent input associated with effort leads to conscious or unconscious decisions to modulate or terminate performance; however, the underlying mechanisms of cerebral control are not fully understood. The idea to move borders of performance with the help of biochemicals is two millennia old. Biochemical findings resulted in highly effective substances widely used to increase performance in daily life, during preparation for sport events and during competition, but many of them must be considered as doping and therefore illegal. Supplements and food have ergogenic potential; however, numerous concepts are controversially discussed with respect to legality and particularly evidence in terms of usefulness and risks. The effect of evidence-based nutritional strategies on adaptations in terms of gene and protein expression that occur in skeletal muscle during and after exercise training sessions is widely unknown. Biochemical research is essential for better understanding of the basic mechanisms causing fatigue and the regulation of the dynamic adaptation to physical and mental training.

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Extracellular matrix: the gatekeeper of tumor angiogenesis

Biochemical Society Transactions ◽

10.1042/bst20190653 ◽

2019 ◽

Vol 47 (5) ◽

pp. 1543-1555 ◽

Cited By ~ 10

Author(s):

Maurizio Mongiat ◽

Simone Buraschi ◽

Eva Andreuzzi ◽

Thomas Neill ◽

Renato V. Iozzo

Keyword(s):

Extracellular Matrix ◽

Tumor Angiogenesis ◽

Signaling Cascades ◽

Cancer Growth ◽

Cell Behavior ◽

Metastatic Progression ◽

Surface Receptors ◽

The Matrix ◽

Multiple Signaling

Abstract The extracellular matrix is a network of secreted macromolecules that provides a harmonious meshwork for the growth and homeostatic development of organisms. It conveys multiple signaling cascades affecting specific surface receptors that impact cell behavior. During cancer growth, this bioactive meshwork is remodeled and enriched in newly formed blood vessels, which provide nutrients and oxygen to the growing tumor cells. Remodeling of the tumor microenvironment leads to the formation of bioactive fragments that may have a distinct function from their parent molecules, and the balance among these factors directly influence cell viability and metastatic progression. Indeed, the matrix acts as a gatekeeper by regulating the access of cancer cells to nutrients. Here, we will critically evaluate the role of selected matrix constituents in regulating tumor angiogenesis and provide up-to-date information concerning their primary mechanisms of action.

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