Naturally Occurring Tumors of the Syrian Hamster

2015 ◽  
pp. 1-12 ◽  
Author(s):  
G. L. Van Hoosier ◽  
J. J. Trentin
Keyword(s):  
Syrian Hamster ◽  
Naturally Occurring

scholarly journals Andes Virus Recognition of Human and Syrian Hamster β3 Integrins Is Determined by an L33P Substitution in the PSI Domain

2009 ◽  
Vol 84 (1) ◽  
pp. 352-360 ◽  
Author(s):  
Valery S. Matthys ◽  
Elena E. Gorbunova ◽  
Irina N. Gavrilovskaya ◽  
Erich R. Mackow
Keyword(s):  
Endothelial Cells ◽  
Syrian Hamster ◽  
Hantavirus Infection ◽  
Human Endothelial Cells ◽  
Hamster Model ◽  
High Affinity ◽  
Naturally Occurring ◽  
Andes Virus ◽  
Integrin Ligand

ABSTRACT Andes virus (ANDV) causes a fatal hantavirus pulmonary syndrome (HPS) in humans and Syrian hamsters. Human αvβ3 integrins are receptors for several pathogenic hantaviruses, and the function of αvβ3 integrins on endothelial cells suggests a role for αvβ3 in hantavirus directed vascular permeability. We determined here that ANDV infection of human endothelial cells or Syrian hamster-derived BHK-21 cells was selectively inhibited by the high-affinity αvβ3 integrin ligand vitronectin and by antibodies to αvβ3 integrins. Further, antibodies to the β3 integrin PSI domain, as well as PSI domain polypeptides derived from human and Syrian hamster β3 subunits, but not murine or bovine β3, inhibited ANDV infection of both BHK-21 and human endothelial cells. These findings suggest that ANDV interacts with β3 subunits through PSI domain residues conserved in both Syrian hamster and human β3 integrins. Sequencing the Syrian hamster β3 integrin PSI domain revealed eight differences between Syrian hamster and human β3 integrins. Analysis of residues within the PSI domains of human, Syrian hamster, murine, and bovine β3 integrins identified unique proline substitutions at residues 32 and 33 of murine and bovine PSI domains that could determine ANDV recognition. Mutagenizing the human β3 PSI domain to contain the L33P substitution present in bovine β3 integrin abolished the ability of the PSI domain to inhibit ANDV infectivity. Conversely, mutagenizing either the bovine PSI domain, P33L, or the murine PSI domain, S32P, to the residue present human β3 permitted PSI mutants to inhibit ANDV infection. Similarly, CHO cells transfected with the full-length bovine β3 integrin containing the P33L mutation permitted infection by ANDV. These findings indicate that human and Syrian hamster αvβ3 integrins are key receptors for ANDV and that specific residues within the β3 integrin PSI domain are required for ANDV infection. Since L33P is a naturally occurring human β3 polymorphism, these findings further suggest the importance of specific β3 integrin residues in hantavirus infection. These findings rationalize determining the role of β3 integrins in hantavirus pathogenesis in the Syrian hamster model.

Colchicine resistance in mammalian cell lines

1975 ◽  
Vol 17 (3) ◽  
pp. 381-396
Author(s):  
P.D. Minor ◽  
D.H. Roscoe
Keyword(s):  
Syrian Hamster ◽  
Permeability Barrier ◽  
Wild Type ◽  
Binding Properties ◽  
Ethyl Methyl ◽  
Mammalian Cell Lines ◽  
Naturally Occurring ◽  
Colchicine Resistance ◽  
Specific Permeability ◽  
Reduced Rate

Colchicine-resistant variants derived from mouse and Syrian hamster lines are described. The resistant cells do not appear to be true mutants, since they appear at a high frequency, unaffected by treatment with ethyl methyl sulphonate, and are unstable in the absence of the drug. They are cross-resistant to other drugs, show a reduced rate of binding of colchicine in monolayer, and give extracts with colchicine-binding properties identical to those of the wild type. Thus the resistance is due to a permeability barrier. The naturally occurring resistance of the Syrian hamster line is specific for colchicine, and may be due to a specific permeability barrier. The Syrian hamster line is also shown to have an extra colchicine-binding pool.

Pathology of Bone Cells in Pigs with Experimental Turbinate Osteoporosis (Atrophic Rhinitis)

1971 ◽  
Vol 29 ◽  
pp. 304-305
Author(s):  
A. W. Fetter ◽  
C. C. Capen
Keyword(s):  
Mucous Membrane ◽  
Bone Cells ◽  
Atrophic Rhinitis ◽  
Infectious Agents ◽  
Metabolic Disturbances ◽  
Progressive Reduction ◽  
Naturally Occurring ◽  
Fundamental Cause ◽  
Osteocytic Osteolysis ◽  
Uncertain Etiology

Atrophic rhinitis in swine is a disease of uncertain etiology in which infectious agents, hereditary predisposition, and metabolic disturbances have been reported to be of primary etiologic importance. It shares many similarities, both clinically and pathologically, with ozena in man. The disease is characterized by deformity and reduction in volume of the nasal turbinates. The fundamental cause for the localized lesion of bone in the nasal turbinates has not been established. Reduced osteogenesis, increased resorption related to inflammation of the nasal mucous membrane, and excessive resorption due to osteocytic osteolysis stimulated by hyperparathyroidism have been suggested as possible pathogenetic mechanisms.The objectives of this investigation were to evaluate ultrastructurally bone cells in the nasal turbinates of pigs with experimentally induced atrophic rhinitis, and to compare these findings to those in control pigs of the same age and pigs with the naturally occurring disease, in order to define the fundamental lesion responsible for the progressive reduction in volume of the osseous core.

High Resolution Replication of Organoclay Surfaces

1982 ◽  
Vol 40 ◽  
pp. 576-577
Author(s):  
W. W. Barker ◽  
W. E. Rigsby ◽  
V. J. Hurst ◽  
W. J. Humphreys
Keyword(s):  
Clay Mineral ◽  
Organic Molecule ◽  
Organic Molecules ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
X Ray ◽  
Naturally Occurring ◽  
Silicate Layers ◽  
Mineral Identification

Experimental clay mineral-organic molecule complexes long have been known and some of them have been extensively studied by X-ray diffraction methods. The organic molecules are adsorbed onto the surfaces of the clay minerals, or intercalated between the silicate layers. Natural organo-clays also are widely recognized but generally have not been well characterized. Widely used techniques for clay mineral identification involve treatment of the sample with H2 O2 or other oxidant to destroy any associated organics. This generally simplifies and intensifies the XRD pattern of the clay residue, but helps little with the characterization of the original organoclay. Adequate techniques for the direct observation of synthetic and naturally occurring organoclays are yet to be developed.

SEM study of the morphological effects of kinetin and zeatin on the growth and development of the apical meristem in wheat

1995 ◽  
Vol 53 ◽  
pp. 978-979
Author(s):  
G. M. Hutchins ◽  
J. S. Gardner
Keyword(s):  
Growth And Development ◽  
Furfuryl Alcohol ◽  
Apical Meristem ◽  
Plant Cells ◽  
Triticum Aestivum L ◽  
Morphological Development ◽  
Naturally Occurring ◽  
Chinese Spring Wheat ◽  
Sem Study ◽  
Moist Environment

Cytokinins are plant hormones that play a large and incompletely understood role in the life-cycle of plants. The goal of this study was to determine what roles cytokinins play in the morphological development of wheat. To achieve any real success in altering the development and growth of wheat, the cytokinins must be applied directly to the apical meristem, or spike of the plant. It is in this region that the plant cells are actively undergoing mitosis. Kinetin and Zeatin were the two cytokinins chosen for this experiment. Kinetin is an artificial hormone that was originally extracted from old or heated DNA. Kinetin is easily made from the reaction of adenine and furfuryl alcohol. Zeatin is a naturally occurring hormone found in corn, wheat, and many other plants.Chinese Spring Wheat (Triticum aestivum L.) was used for this experiment. Prior to planting, the seeds were germinated in a moist environment for 72 hours.

Fine structure and properties of defects in naturally occurring silicates and oxides

1990 ◽  
Vol 48 (4) ◽  
pp. 460-461
Author(s):  
David R. Veblen
Keyword(s):  
Chemical Reactions ◽  
High Resolution Electron Microscopy ◽  
Extended Defects ◽  
Single Chain ◽  
Naturally Occurring ◽  
Resolution Electron ◽  
Fine Structures ◽  
Image Simulations ◽  
Similar Crystal Structure

Extended defects and interfaces control many processes in rock-forming minerals, from chemical reactions to rock deformation. In many cases, it is not the average structure of a defect or interface that is most important, but rather the structure of defect terminations or offsets in an interface. One of the major thrusts of high-resolution electron microscopy in the earth sciences has been to identify the role of defect fine structures in reactions and to determine the structures of such features. This paper will review studies using HREM and image simulations to determine the structures of defects in silicate and oxide minerals and present several examples of the role of defects in mineral chemical reactions. In some cases, the geological occurrence can be used to constrain the diffusional properties of defects.The simplest reactions in minerals involve exsolution (precipitation) of one mineral from another with a similar crystal structure, and pyroxenes (single-chain silicates) provide a good example. Although conventional TEM studies have led to a basic understanding of this sort of phase separation in pyroxenes via spinodal decomposition or nucleation and growth, HREM has provided a much more detailed appreciation of the processes involved.

Flavonoids in adipose tissue inflammation and atherosclerosis: one arrow, two targets

2020 ◽  
Vol 134 (12) ◽  
pp. 1403-1432 ◽  
Author(s):  
Manal Muin Fardoun ◽  
Dina Maaliki ◽  
Nabil Halabi ◽  
Rabah Iratni ◽  
Alessandra Bitto ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Fruits And Vegetables ◽  
Metabolic Diseases ◽  
Therapeutic Agents ◽  
Adipose Tissue Inflammation ◽  
Cellular Mechanisms ◽  
Tissue Inflammation ◽  
Cholesterol Levels ◽  
Naturally Occurring ◽  
Pro Inflammatory Cytokines

Abstract Flavonoids are polyphenolic compounds naturally occurring in fruits and vegetables, in addition to beverages such as tea and coffee. Flavonoids are emerging as potent therapeutic agents for cardiovascular as well as metabolic diseases. Several studies corroborated an inverse relationship between flavonoid consumption and cardiovascular disease (CVD) or adipose tissue inflammation (ATI). Flavonoids exert their anti-atherogenic effects by increasing nitric oxide (NO), reducing reactive oxygen species (ROS), and decreasing pro-inflammatory cytokines. In addition, flavonoids alleviate ATI by decreasing triglyceride and cholesterol levels, as well as by attenuating inflammatory mediators. Furthermore, flavonoids inhibit synthesis of fatty acids and promote their oxidation. In this review, we discuss the effect of the main classes of flavonoids, namely flavones, flavonols, flavanols, flavanones, anthocyanins, and isoflavones, on atherosclerosis and ATI. In addition, we dissect the underlying molecular and cellular mechanisms of action for these flavonoids. We conclude by supporting the potential benefit for flavonoids in the management or treatment of CVD; yet, we call for more robust clinical studies for safety and pharmacokinetic values.

Effect of intestinal alkalinization on irinotecan (CPT-11)-induced diarrhea in the golden Syrian hamster model

2001 ◽  
Vol 120 (5) ◽  
pp. A613-A613
Author(s):  
T IKEGAMI ◽  
P LATHAM ◽  
K KOBAYASHI ◽  
K ARIMORI ◽  
B BOUSCAREL
Keyword(s):  
Syrian Hamster ◽  
Hamster Model ◽  
Golden Syrian Hamster

Molecular Mechanism of Apoptosis Induction by Resveratrol, a Natural Cancer Chemopreventive Agent

2008 ◽  
Vol 78 (1) ◽  
pp. 3-8 ◽  
Author(s):  
Fan ◽  
Jiang ◽  
Zhang ◽  
Bai
Keyword(s):  
Cancer Treatment ◽  
Molecular Mechanism ◽  
Apoptosis Induction ◽  
Protective Agents ◽  
Chemopreventive Agent ◽  
Naturally Occurring ◽  
Apoptosis Pathways ◽  
Present Understanding

In efforts to identify naturally occurring compounds that act as protective agents, resveratrol, a phytoalexin existing in wine, has attracted much interest because of its diverse pharmacological characteristics. Considering that apoptosis induction is the most potent defense approach for cancer treatment, we have tried to summarize our present understanding of apoptosis induction by resveratrol based on the two major apoptosis pathways.

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