scholarly journals Isolation of Choriomammotropin from the Ovine Placentome

1984 ◽  
Vol 37 (2) ◽  
pp. 63 ◽  
Author(s):  
CM Leach Harper ◽  
V L Ford ◽  
GD Thorburn
Keyword(s):  
Protease Inhibitors ◽  
Density Gradient ◽  
Gestational Age ◽  
Density Gradient Centrifugation ◽  
Gradient Centrifugation ◽  
Soluble Form ◽  
Sample Zone ◽  
Second Gradient ◽  
Particulate Form ◽  
Triton X

Placentomes, taken from ewes at 101-141 days gestation, were homogenized and subjected to differential and density gradient centrifugation. In the presence or absence of protease inhibitors, choriomammotropin (ovine chorionic somatomammotropin, oCS) was detected by radioimmunoassay, and banded at two positions in 30-60% w/v sucrose gradients. The first band (soluble form) eluted in the sample zone of the gradient and contained 33�6� 1 % (mean�s.e.m., n = 10) of the total oCS present in the gradient. The remainder (48� 7�6%) of the oCS (particulate form) sedimented to 37�5-43% w/v sucrose. Both these bands became sharper with decreasing protein loaded onto the gradients. 125I_oCS, pre-equilibrated with a placentome preparation, eluted in the same position as the first band of endogenous oCS. When loaded onto a second gradient the second band eluted at 38-41 % w /v sucrose, but after being subjected to ultrasonic disruption or treatment with Triton X-I00 this oCS eluted in the sample zone. There was no correlation between gestational age of the ewe and the percentage oCS in either the soluble or particulate form, the concentration of oCS, or enrichment by protein.

The Combining Ability of Glycoproteins IIb, IIIa and Ca2+ in EDTA-Treated Nonaggregable Platelets

1983 ◽  
Vol 50 (04) ◽  
pp. 848-851 ◽  
Author(s):  
Marjorie B Zucker ◽  
David Varon ◽  
Nicholas C Masiello ◽  
Simon Karpatkin
Keyword(s):  
Density Gradient ◽  
Combining Ability ◽  
Density Gradient Centrifugation ◽  
Gradient Centrifugation ◽  
Electrophoretic Pattern ◽  
Sucrose Density Gradient ◽  
Irreversible Loss ◽  
Sucrose Density Gradient Centrifugation ◽  
Crossed Immunoelectrophoresis ◽  
Triton X

SummaryPlatelets deprived of calcium and incubated at 37° C for 10 min lose their ability to bind fibrinogen or aggregate with ADP when adequate concentrations of calcium are restored. Since the calcium complex of glycoproteins (GP) IIb and IIIa is the presumed receptor for fibrinogen, it seemed appropriate to examine the behavior of these glycoproteins in incubated non-aggregable platelets. No differences were noted in the electrophoretic pattern of nonaggregable EDTA-treated and aggregable control CaEDTA-treated platelets when SDS gels of Triton X- 114 fractions were stained with silver. GP IIb and IIIa were extracted from either nonaggregable EDTA-treated platelets or aggregable control platelets with calcium-Tris-Triton buffer and subjected to sucrose density gradient centrifugation or crossed immunoelectrophoresis. With both types of platelets, these glycoproteins formed a complex in the presence of calcium. If the glycoproteins were extracted with EDTA-Tris-Triton buffer, or if Triton-solubilized platelet membranes were incubated with EGTA at 37° C for 30 min, GP IIb and IIIa were unable to form a complex in the presence of calcium. We conclude that inability of extracted GP IIb and IIIa to combine in the presence of calcium is not responsible for the irreversible loss of aggregability that occurs when whole platelets are incubated with EDTA at 37° C.

scholarly journals Release of platelet fibronectin (cold-insoluble globulin) from alpha granules induced by thrombin or collagen; lack of requirement for plasma fibronectin in ADP-induced platelet aggregation

Blood ◽  
1979 ◽  
Vol 54 (1) ◽  
pp. 8-12 ◽  
Author(s):  
MB Zucker ◽  
MW Mosesson ◽  
MJ Broekman ◽  
KL Kaplan
Keyword(s):  
Platelet Aggregation ◽  
Density Gradient ◽  
Density Gradient Centrifugation ◽  
Gradient Centrifugation ◽  
Subcellular Fractions ◽  
Plasma Fibronectin ◽  
Cold Insoluble Globulin ◽  
Triton X ◽  
Induced Aggregation

Platelets lysed with Triton X-100 contain 3.44 +/- 1.27 (SD) microgram of fibronectin (cold-insoluble globulin) per 10(9) platelets. Fibronectin was partially released from washed whole platelets by collagen or thrombin, and its release by collagen was inhibited by aspirin. Analysis of subcellular fractions obtained by density-gradient centrifugation of disrupted platelets indicated that fibronectin was contained in the alpha granules. Fibrinogen depleted of fibronectin (less than 2 microgram/mg) supported ADP-induced aggregation as effectively as fibrinogen contaminated with this protein, thus reinforcing the generally held view that fibrinogen itself is the necessary protein cofactor in this reaction.

scholarly journals Release of platelet fibronectin (cold-insoluble globulin) from alpha granules induced by thrombin or collagen; lack of requirement for plasma fibronectin in ADP-induced platelet aggregation

Blood ◽  
1979 ◽  
Vol 54 (1) ◽  
pp. 8-12 ◽  
Author(s):  
MB Zucker ◽  
MW Mosesson ◽  
MJ Broekman ◽  
KL Kaplan
Keyword(s):  
Platelet Aggregation ◽  
Density Gradient ◽  
Density Gradient Centrifugation ◽  
Gradient Centrifugation ◽  
Subcellular Fractions ◽  
Plasma Fibronectin ◽  
Cold Insoluble Globulin ◽  
Triton X ◽  
Induced Aggregation

Abstract Platelets lysed with Triton X-100 contain 3.44 +/- 1.27 (SD) microgram of fibronectin (cold-insoluble globulin) per 10(9) platelets. Fibronectin was partially released from washed whole platelets by collagen or thrombin, and its release by collagen was inhibited by aspirin. Analysis of subcellular fractions obtained by density-gradient centrifugation of disrupted platelets indicated that fibronectin was contained in the alpha granules. Fibrinogen depleted of fibronectin (less than 2 microgram/mg) supported ADP-induced aggregation as effectively as fibrinogen contaminated with this protein, thus reinforcing the generally held view that fibrinogen itself is the necessary protein cofactor in this reaction.

Uranyl Acetate and Rotary Shadowing to Increase the Contrast of Small Aggregated Virus Particles

1969 ◽  
Vol 27 ◽  
pp. 424-425
Author(s):  
Lee F. Ellis ◽  
Richard M. Van Frank ◽  
Walter J. Kleinschmidt
Keyword(s):  
Electron Microscopy ◽  
Tissue Culture ◽  
Density Gradient ◽  
Density Gradient Centrifugation ◽  
Gradient Centrifugation ◽  
Uranyl Acetate ◽  
Interferon Inducer ◽  
Virus Particles ◽  
Staining Methods ◽  
Rotary Shadowing

The extract from Penicillum stoliniferum, known as statolon, has been purified by density gradient centrifugation. These centrifuge fractions contained virus particles that are an interferon inducer in mice or in tissue culture. Highly purified preparations of these particles are difficult to enumerate by electron microscopy because of aggregation. Therefore a study of staining methods was undertaken.

scholarly journals Sperm selection of cryopreserved milt of catfish (Rhamdia quelen) by density gradient centrifugation with AllGrad® 90%

MethodsX ◽  
2021 ◽  
pp. 101422
Author(s):  
Maritza Pérez Atehortúa ◽  
Andrea Galuppo ◽  
Rômulo Batista Rodrigues ◽  
Nathalia dos Santos Teixeira ◽  
Thaiza Rodrigues de Freitas ◽  
...  
Keyword(s):  
Density Gradient ◽  
Density Gradient Centrifugation ◽  
Gradient Centrifugation ◽  
Sperm Selection ◽  
Rhamdia Quelen ◽  
Selection Of
Sign in / Sign up

Export Citation Format

Share Document