Electrophoretic mobility of partially denatured DNA in a gel: Qualitative and semiquantitative differences between bubbles and split ends

2012 ◽  
Vol 33 (9-10) ◽  
pp. 1341-1348 ◽  
Author(s):  
David Sean ◽  
Gary W. Slater
Keyword(s):  
Electrophoretic Mobility ◽  
Split Ends

Factor VIII-Related Activities in Normal, Haemophilic and von Willebrand’s Disease Platelet Fractions

1978 ◽  
Vol 40 (02) ◽  
pp. 288-301 ◽  
Author(s):  
P Meucci ◽  
I R Peake ◽  
A L Bloom
Keyword(s):  
Factor Viii ◽  
Electrophoretic Mobility ◽  
Concanavalin A ◽  
Freezing And Thawing ◽  
Von Willebrand's Disease ◽  
Factor Viii Related Antigen ◽  
Von Willebrand’S Disease ◽  
Normal Plasma ◽  
Significant Difference ◽  
Ristocetin Cofactor

SummaryFactor VIII-related activities have been studied in platelet fractions in order to try to reconcile the conflicting findings of other workers, and to extend the studies. In platelets from 16 normal subjects procoagulant factor VIII was not detected. The amount of factor VIII-related antigen (FVIIIR: AG) in the cytosol per mg of protein was about twice that in the membrane fraction and about ten times that in the debris fraction. There was no significant difference between the amount of FVIIIR: AG and ristocetin cofactor (RistCof) activity in each fraction. The findings in haemophilic platelets were similar. In von Willebrand’s disease (vWd) one serverely affected patient had no detectable factor VIII related activities in any platelet fraction. In 5 patients with intermediate vWd results were normal. In a further 5, with more prolonged bleeding times, no FVIIIR: RistCof was detected in platelets, despite a normal amount of FVIIIR: AG in the cytosol and debris. The electrophoretic mobility of cytosol FVIIIR: AG was increased in all normals and patients, while that in the membrane and debris fractions had normal mobility. Cytosol FVIIIR: AG eluted later than normal FVIIIR: AG on gel filtration on Sepharose 2B, and also showed reduced antibody binding in an immunoradiometric assay. Precipitation of FVIIIR: AG by concanavalin A was incomplete in all platelet fractions from normals, and even more reduced in vWd platelet fractions. The results suggest the possibility of two types of platelet FVIIIR: AG.A factor VIII-related antigen was shown to be associated with normal washed platelets by immunofluorescence techniques (Bloom et al. 1973). Since then, several studies have been reported on the localisation of factor VIII related antigen (FVIIIR: AG), factor VIII procoagulant activity (FVIII: C) and factor VIII related ristocetin cofactor activity (FVIIIR: RistCof) within the platelets. Initially, Howard et al. (1974) indicated that FVIIIR: AG was firmly bound to the platelet membrane, and noted that in lysed platelets the level of FVIIIR: AG as measured by electroimmunodiffusion was higher than that in whole platelet suspensions. However, further studies by Nachman and Jaffe (1975) showed that FVIIIR: AG was also present to a considerable extent in the granules, and they detected none in the platelet cytosol. Bouma and colleagues (1975) were, however, able to find FVIIIR: AG and FVIIIR: RistCof in the cytosol upon freezing and thawing platelets. This FVIIIR: AG had an electrophoretic mobility comparable to that of normal plasma. They also noted that platelets which were air dried apparently had a granular FVIIIR:AG localisation by immunfluorescence; however, intact platelets in suspension did not stain by this method.Recently Ruggeri et al. (1977) and Sultan et al. (1977) have also found FVIIIR: AG in the cytosol, and the former authors reported it to have increased electrophoretic mobility when compared to normal plasma FVIIIR:AG. Results concerning the localisation of FVIIIR: AG in normal platelets have thus been conflicting. Similarly, in the few reports available concerning platelet FVIIIR: AG in von Willibrand’s disease variable results have also been obtained (Ruggeri et al. 1977, Howard et al. 1974, Shearn et al. 1974 and Bouma et al. 1975).In this study we report on the localisation of factor VIII-related activities in normal, haemophilic and von Willebrand’s disease platelets using available standard techniques as well as precipitation of FVIIIR: AG with the plant lectin concanavalin A, a procedure which has been shown to detect abnormal forms of FVIIIR:AG in certain types of von Willebrand’s disease (Peake and Bloom 1977).

Assessment of Damage to Human Platelets after Aggregation and Other Injuries by Microscopic Observation and Estimation of Serotonin Uptake

1970 ◽  
Vol 23 (02) ◽  
pp. 261-275 ◽  
Author(s):  
G Zbinden ◽  
J. N Mehrishi ◽  
S Tomlin
Keyword(s):  
Platelet Aggregation ◽  
Electrophoretic Mobility ◽  
Human Platelets ◽  
Freezing And Thawing ◽  
Low Degree ◽  
Microscopic Evaluation ◽  
Negative Surface ◽  
Negative Surface Charge ◽  
Charged Macromolecules ◽  
5 Ht Uptake

SummaryThe severity of platelet damage induced by hyper- and hypotonic NaCl solutions and freezing and thawing was assessed by microscopic evaluation and measuring inhibition of 5-HT uptake. The same techniques were used to quantitate the effects of aggregating agents. The positively charged macromolecules PS, Poly-L und Poly-O reduced the net negative surface charge as determined by microelectrophoresis, caused platelet aggregation and inhibited 5-HT uptake. The damaging effects of Poly-L and Poly-O were more severe and more closely related to concentration than that of PS. The negatively charged macromolecules Poly-IC and NaPS increased the anodic electrophoretic mobility. Poly-IC and heparin caused a low degree of platelet clumping and no inhibition of 5-HT uptake. NaPS produced severe platelet damage with extensive clumping and complete inhibition of 5-HT uptake. Na laurate had the same effect, but did not alter electrophoretic mobility. ADP caused concentration-dependent platelet aggregation and inhibition of 5-HT uptake. The effects of ADP and NaPS were compared in agitated and non-agitated platelet samples containing identical concentrations of the 2 compounds. Agitation was found to increase the degree of platelet clumping and to reduce 5-HT uptake.

Studies on the Degradation of Human Fibrinogen by Plasmin and Trypsin

1966 ◽  
Vol 16 (03/04) ◽  
pp. 526-540 ◽  
Author(s):  
E. A Beck ◽  
D. P Jackson
Keyword(s):  
Physicochemical Properties ◽  
Electrophoretic Mobility ◽  
Rapid Loss ◽  
Clotting System ◽  
Human Fibrinogen ◽  
Peptide Bonds ◽  
Physico Chemical ◽  
Starch Gel ◽  
Ph Stat ◽  
Rapid Appearance

SummaryThe effects of trypsin and plasmin on the functional and physicochemical properties of purified human fibrinogen were observed at various stages of proteolysis. Concentrations of plasmin and trypsin that produced fibrinogenolysis at comparable rates as measured in a pH stat produced, at similar rates, loss of precipitability of fibrinogen by heat and ammonium sulphate and alterations in electrophoretic mobility on starch gel. Trypsin produced a more rapid loss of clottability of fibrinogen and a more rapid appearance of inhibitors of the thrombin-fibrinogen clotting system than did plasmin. Consistent differences were noted between the effects of trypsin and plasmin on the immunoelectrophoretic properties of fibrinogen during the early stages of proteolysis.These results are consistent with the hypothesis that trypsin initially reacts with the same peptide bonds of fibrinogen that are split by thrombin, but these same bonds do not appear to be split initially by plasmin. Measurement of the various functional and physico-chemical changes produced by the action of trypsin and plasmin on fibrinogen can be used to recognize various stages of proteolysis.

Immunological Evidence for Prothrombin in Human Platelets

1986 ◽  
Vol 55 (02) ◽  
pp. 268-270
Author(s):  
R J Alexander
Keyword(s):  
Electrophoretic Mobility ◽  
Platelet Activation ◽  
Double Diffusion ◽  
Human Platelets ◽  
Secreted Proteins ◽  
Platelet Surface ◽  
Activated Platelets ◽  
Similar Protein ◽  
Diffusion Assay ◽  
Supernatant Solution

SummaryAn attempt was made to isolate from plasma the platelet surface substrate for thrombin, glycoprotein V (GPV), because a GPV antigen was reported to be present in plasma (3). Plasma fractionation based on procedures for purification of GPV from platelets revealed a thrombin-sensitive protein with appropriate electrophoretic mobility. The protein was purified; an antiserum against it i) reacted with detergent-solubilized platelet proteins or secreted proteins in a double diffusion assay, ii) adsorbed a protein from the supernatant solution of activated platelets, and iii) inhibited thrombin-induced platelet activation, but the antiserum did not adsorb labeled GPV. The purified protein was immunochemically related to prothrombin rather than to GPV. Other antibodies against prothrombin were also able to adsorb a protein from platelets. It is concluded that 1) plasma does not contain appreciable amounts of GPV, and 2) platelets contain prothrombin or an immunochemically similar protein.

Flocculation of Waste Waters from Petroleum Refineries

1974 ◽  
Vol 9 (1) ◽  
pp. 302-314
Author(s):  
André Hade ◽  
Acher Elcabetz
Keyword(s):  
Electrophoretic Mobility ◽  
Light Transmittance ◽  
Waste Waters ◽  
Critical Coagulation Concentration ◽  
Mobility Rate ◽  
Anionic Polymers ◽  
Petroleum Refineries ◽  
Binary Suspension

Abstract Waste waters from petroleum refineries can be considered as a ternary-like system, the components of which have been characterized. They are: the alkaline liquor, the hydrocarbon rich oil in suspension and the silica rich solid also in suspension. The parameters controlling the destabilization and the flocculation of these suspensions have been studied by light transmittance and electrophoretic mobility. Rate of flocculation, critical coagulation concentration (CCC) , critical restabilization concentration and optimum flocculation conditions have been determined for different combinations of added polyelectrolytes and/or simple electrolytes. Among eleven different polyelectrolytes, four of the cationic type were selected for their property to flocculate the suspension. It has been shown that an excess of polyelectrolyte brings about the restabilization of the particules. No flocculation has been observed for any of the anionic polymers tested. Simple electrolytes are found to obey the Schulze-Hardy rule in their flocculation capacity. Various combinations of a polyelectrolyte with a simple salt lead to a lower CCC together with a broader concentration range between destabilization and restabilization. It is concluded that this binary suspension behaved essentially like a classical lyophobic sol.

Theoretical Principles of Streaming Current Detection

1989 ◽  
Vol 21 (6-7) ◽  
pp. 443-453 ◽  
Author(s):  
S. K. Dentel ◽  
K. M. Kingery
Keyword(s):  
Velocity Profile ◽  
Electrophoretic Mobility ◽  
Double Layer ◽  
Initial Attempt ◽  
Streaming Current ◽  
Coagulant Dosage ◽  
Model Predictions ◽  
Double Layer Model ◽  
Simplifying Assumptions ◽  
Current Detection

In spite of the increased use of streaming current detectors (SCDs) as a means of monitoring and/or controlling coagulant dosage, knowledge regarding fundamental workings is incomplete. This paper provides an initial attempt at predicting and verifying functioning compared to electrophoretic mobility. The instrument's components -- the sensor and the signal processor -- are first described. Equations modelling electro-double layer behavior in its sensor are then developed. Simplifying assumptions include the use of a capacitance model of the double layer and a triangular velocity profile for fluid within the sensor's annulus. More complex modelling approaches are also suggested which incorporate the Gouy-Chapman electro-double layer model and an exact solution for the velocity profile. Experimental results confirm predictions of the simplified model under conditions of low potential. A monotonic relationship exists between streaming current electrophoretic mobility, which is required for its use as a control parameter. Deviations from model predictions are suggested to be due to charge characteristics of the sensor surfaces themselves.

scholarly journals VARIATION IN BIOCHEMICAL PROPERTIES OF ALLOZYMES OF XANTHINE DEHYDROGENASE IN DROSOPHILA PSEUDOOBSCURA

Genetics ◽  
1980 ◽  
Vol 96 (4) ◽  
pp. 927-938
Author(s):  
David R Wilcox ◽  
Satya Prakash
Keyword(s):  
Substrate Specificity ◽  
Binding Affinity ◽  
Electrophoretic Mobility ◽  
Significant Variation ◽  
Xanthine Dehydrogenase ◽  
Biochemical Properties ◽  
Variant Allele ◽  
Drosophila Pseudoobscura ◽  
Mesa Verde

ABSTRACT Twenty-six D. pseudoobscura strains isogenic for xanthine dehydrogenase alleles from Mesa Verde, Colorado, were tested for differences in the biochemical properties of different allelic forms of xanthine dehydrogenase. No significant differences in binding affinity (Km) or substrate specificity of the enzyme were found. Significant variation among strains, in activity (V  max) and among electromorphs, as well as among strains, in thermolability was found. For the few strains tested, the activity and thermolability differences were shown to co-segregate with the electrophoretic mobility of the variant allele.

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