THE EFFECT OF SIALIDASE ON PIG TRANSFERRINS

1963 ◽  
Vol 41 (1) ◽  
pp. 2523-2527 ◽  
Author(s):  
F. K. Kristjansson ◽  
J. D. Cipera
Keyword(s):  
Sialic Acid ◽  
Electrophoretic Mobility ◽  
High Voltage ◽  
Migration Rates ◽  
The Difference

1. Sialidase digestion resulted in a decreased electrophoretic mobility of pig transferrins without destroying their ability to bind iron.2. The decrease in electrophoretic mobility occurred in two distinct steps.3. The migration rates of the final sialidase digestion products of TfA and TfB suggest that the difference in mobilities of TfA and TfB is not due to a difference in the amount of sialic acid which each contains.4. The mobility differences between the three zones observed for both TfA and TfB under high voltage Tris–citrate gel analyses do not appear to be due to the amount of sialic acid possessed by each.

THE EFFECT OF SIALIDASE ON PIG TRANSFERRINS

1963 ◽  
Vol 41 (12) ◽  
pp. 2523-2527 ◽  
Author(s):  
F. K. Kristjansson ◽  
J. D. Cipera
Keyword(s):  
Sialic Acid ◽  
Electrophoretic Mobility ◽  
High Voltage ◽  
Migration Rates ◽  
The Difference

1. Sialidase digestion resulted in a decreased electrophoretic mobility of pig transferrins without destroying their ability to bind iron.2. The decrease in electrophoretic mobility occurred in two distinct steps.3. The migration rates of the final sialidase digestion products of TfA and TfB suggest that the difference in mobilities of TfA and TfB is not due to a difference in the amount of sialic acid which each contains.4. The mobility differences between the three zones observed for both TfA and TfB under high voltage Tris–citrate gel analyses do not appear to be due to the amount of sialic acid possessed by each.

The role of hemorheological disorders in the pathogenesis of hemorrhagic pancreonecrosis

2021 ◽  
Author(s):  
Н.П. Александрова ◽  
В.И. Карандашов ◽  
А.В. Варданян
Keyword(s):  
Sialic Acid ◽  
Shear Rate ◽  
Electrophoretic Mobility ◽  
Blood Viscosity ◽  
Proteolytic Enzymes ◽  
Biologically Active ◽  
Erythrocyte Aggregation ◽  
Control Group ◽  
Mechanical Resistance

Введение. Вопросы патогенеза острого панкреатита и панкреонекроза до настоящего времени остаются в центре внимания исследователей и клиницистов. До сих пор до конца не выяснена роль изменений в системе гемостаза и гемореологических нарушений в развитии этого заболевания. Цель исследования: установить роль гемореологических нарушений в патогенезе геморрагического панкреонекроза и изучить специфику механизма этих расстройств. Материалы и методы. Обследовано 29 пациентов с геморрагическим панкреонекрозом (12 женщин и 17 мужчин) в возрасте от 23 до 60 лет. Исследовали вязкость крови, показатель гематокрита, количество эритроцитов и их диаметр, агрегацию, электрофоретическую подвижность, деформируемость и механическую резистентность эритроцитов, белковый состав плазмы, содержание сиаловой кислоты в плазме и в эритроцитах, параметры липидного обмена, содержание кальция и фибриногена в крови,фибринолитическую активность крови и агрегационную активность тромбоцитов, гемокоагуляционная активность исследована методом тромбоэластографии. Для определения нормальных значений исследованных показателей было обследовано 15 практически здоровых лиц (7 женщин и 8 мужчин). Результаты. У больных панкреонекрозом самым грубым нарушениям подвергаются эритроциты: их механическая резистентность снижалась в 2 раза, объем увеличивался на 18,7%, деформируемость падала на 43,8%, количество снижалось на 8,75%, показатель гематокрита при этом оставался на уровне нормальных значений по причине увеличенного объема (сферичности) клеток; в 1,8 раза возрастала агрегация эритроцитов. Вязкость крови при скорости сдвига 1 c–1 увеличивалась в 3,3 раза, а при скорости сдвига 150 c–1 — в 1,58 раза по сравнению с нормой. Причиной повышения агрегации эритроцитов являлось снижение их электрофоретической подвижности на 35,9% из-за десиализации их мембран: концентрация сиаловой кислоты в клеточных мембранах была снижена на 20,8%, а содержание конъюгированной сиаловой кислоты в плазме увеличено в 2,25 раза по сравнению с нормальными значениями. Заключение. Гемореологические расстройства, которые возникают первоначально у больных геморрагическим панкреонекрозом как результат некротических изменений поджелудочной железы, с определенного, довольно раннего этапа сами становятся фактором патогенеза данного заболевания. Доминирующим фактором прогрессивного увеличения вязкости крови у больных панкреонекрозом является нарушение морфофункциональных и физико-химических свой ств эритроцитов на фоне высокой активности протеолитических ферментов, биологически активных аминов и крайней степени токсемии. Background. The pathogenesis of acute pancreatitis and pancreonecrosis is still the focus of researchers and clinicians. The role of hemorheological disorders in these diseases remain uncertain until now. Objectives: to define the role of hemorheological disorders in the pathogenesis of hemorrhagic pancreonecrosis and to study the specifics of the mechanism of these disorders. Patients/Methods. This study included 29 patients (12 women and 17 men, age of 23 to 60 years old) with hemorrhagic pancreatic necrosis. We examined blood viscosity, hematocrit and some erythrocyte properties as count, diameter, aggregation, electrophoretic mobility, deformability and mechanical resistance; other investigated parameters were plasma protein composition, plasma and erythrocytes sialic acid concentrations, lipids, total calcium and fibrinogen concentrations, blood fibrinolytic activity, platelets aggregation activity; total hemocoagulation activity was studied with thromboelastography. Control group contained 15 practically healthy individuals (7 women and 8 men). Results. Expressed disturbances of blood rheological properties, mostly in erythrocytes were detected in patients with pancreonecrosis. Red blood cells (RBC) showed 2-times decreasing of mechanical resistance, of their volume by 18.7%, of deformability by 43.8%, of count by 8.75%. Hematocrit remained normal level due to RBC increased volume (sphericity). RBC aggregation had been increased by 1.8 times. Blood viscosity at the shear rate of 1 s–1 was increased by 3.3 times and at the shear rate of 150 s–1 by 1.58 times. Raised erythrocyte aggregation was caused by a decrease of RBC electrophoretic mobility of 35.9%. Sialic acid concentration in RBC membranes was lower of 20.8% whereas conjugated sialic acid in plasma showed increasing by 2.25 times. Conclusions. RBC morphofunctional and physicochemical disturbances cause the increase in blood viscosity in patients with pancreonecrosis. It is distinguishing feature of hemorheological disorders in hemorrhagic pancreonecrosis developing, seems, due to high activity of proteolytic enzymes and biologically active amines. Of particular importance in hemorrhagic pancreonecrosis belong to platelet involving into intravascular coagulation.

Study On The Effect Of Ddavp On Factor VIII- Related Properties In Hemophilia And VWD

1981 ◽  
Author(s):  
N Ciavarella ◽  
S Solinas ◽  
D Pilolli ◽  
P Ranieri ◽  
D Corrao ◽  
...  
Keyword(s):  
Factor Viii ◽  
Electrophoretic Mobility ◽  
Hemophilia A ◽  
The Other ◽  
Strong Response ◽  
The Difference ◽  
Classic Form ◽  
O 19

Twenty-one patients affected by mild and moderate Hemophilia A as well as 9 patients with the classic form of vonWillebrand’s disease (vWD) were given a total of 58 infusions of DDAVP. Concerning Hemophilia a three fold mean raise ( x = 3.0, sem O. 19; range of ratios post/preinfusion 1.35 - 5.55) of factor VIII : C levels was observed after the infusion of 0.3 μg/Kg b.w. A mean raise of 3.44 ( sem 0.48, range 2.20 - 6.7) after the infusion of 0.4/ug/Kg was found. The difference between the two regimens is not statistically significant (p < 0.5). As to the vWD 18 infusions were given. In 6 patients the changes of factor VI1I: C, VIIIR: Ag and VIII: vWF were roughly consensual ( ratios post/preinfusion ranging from 2.2 to 4.0 for VIII: C; from 1.8 to 3.5 for VIHR:Ag and from 3.1 to 6.2 for VIII: vWF). In the remaining 3 patients a very strong response of VIII : C ( ratios post/preinfusion 12.0, 15.1 and 6.5) was observed. Also the other properties related to factor VIII underwent to relevant increase. In one of these patients a modified electrophoretic mobility of factor VIII was found; the other two (father and doughter) had a normal factor VIII mobility after stimulation with DDAVP.

Dimensional Effects on the Measurement of Permittivity of Semiconducting Materials Used in High Voltage XLPE Cables

2008 ◽  
Vol 9 (1) ◽  
Author(s):  
Juan Juan Yang ◽  
Da Ming Zhang
Keyword(s):  
High Voltage ◽  
Partial Discharge ◽  
Semiconducting Materials ◽  
Dimensional Effect ◽  
Semiconducting Material ◽  
Dimensional Effects ◽  
Different Dimensions ◽  
The Difference ◽  
Materials Used ◽  
Set Up

The intrinsic permittivity, not apparent permittivity, of semiconducting layers of high voltage cross-linked polyethylene (XLPE) cables imposes a significant influence on the design of partial discharge detecting sensors. It has extremely high permittivity, resulting in a dimensional effect, an embodiment of the difference between the intrinsic permittivity and apparent or measurable permittivity. To investigate this dimensional effect in semiconducting material, a mathematical model is set up in this paper for a capacitor with two rectangular-shaped electrodes in parallel, between which is inserted a semi-conducting sample. First, the expression of the electric field in the semiconducting material is worked out theoretically. Then, the measurable or apparent complex permittivity is expressed as a function of intrinsic permittivity, dimensions of the sample and frequency. Next, five blocks with different dimensions are introduced to study the dimensional effect. The numerical analysis demonstrates that above 10 MHz, samples with different dimensions result in different apparent permittivity or measurable permittivity if experiments are carried out for the samples with the assumed dimensions. This implies that dimensional effects should be considered when accurate intrinsic permittivity of the semiconducting materials is needed.

scholarly journals Investigations on the oligosaccharide units of an A myeloma globulin

1968 ◽  
Vol 107 (3) ◽  
pp. 341-352 ◽  
Author(s):  
G. Dawson ◽  
J. R. Clamp
Keyword(s):  
Sialic Acid ◽  
Electrophoretic Mobility ◽  
Acid Content ◽  
Carbohydrate Content ◽  
Glycosidic Linkage ◽  
Core Oligosaccharide ◽  
Sialic Acid Content ◽  
Acetylneuraminic Acid ◽  
The Core ◽  
Polypeptide Chains

The carbohydrate content of an A myeloma globulin was investigated. The carbohydrate content was found to be unchanged when the protein was isolated from the patient over a period of 18 months. The various polymeric forms of the protein contained similar proportions of carbohydrate. The A myeloma globulin contained approx. 2 residues of 6-deoxy-l-galactose (l-fucose), 14–15 of d-mannose, 12–13 of d-galactose, 12–13 of 2-acetamido-2-deoxy-d-glucose (N-acetyl-d-glucosamine), 6 of 2-acetamido-2-deoxy-d-galactose (N-acetyl-d-galactosamine) and 5 of N-acetylneuraminic acid (sialic acid), and these were distributed between six oligosaccharide units all of which were present on the heavy polypeptide chains. The oligosaccharide units showed two kinds of heterogeneity, which have been termed central and peripheral. Central heterogeneity was shown by the presence of three completely different core units, which had the following compositions: (1) 3 residues of d-galactose and 3 of 2-acetamido-2-deoxy-d-galactose, joined to protein by an O-glycosidic linkage between acetamidohexose and serine; (2) 3 residues of d-mannose, 2 of d-galactose and 3 of 2-acetamido-2-deoxy-d-glucose, joined to protein by an N-glycosidic linkage between acetamidohexose and aspartic acid; (3) 4 residues of d-mannose and 3 of 2-acetamido-2-deoxy-d-glucose with a linkage similar to that in (2). The core oligosaccharide units showed peripheral heterogeneity in the attachment of 6-deoxy-l-galactose, 2-acetamido-2-deoxy-d-glucose and N-acetylneuraminic acid. Tentative structures are proposed for these various types of oligosaccharide unit. Glycopeptides were isolated in which the sialic acid content exceeded that of d-galactose. Explanations are given for the electrophoretic mobility and staining characteristics of the various glycopeptides.

Partial resialylation of human asialotransferrin types 1 and 2 in the rat

1984 ◽  
Vol 62 (9) ◽  
pp. 853-858 ◽  
Author(s):  
Erwin Regoeczi ◽  
Paul A. Chindemi ◽  
Maria T. Debanne
Keyword(s):  
Sialic Acid ◽  
Electrophoretic Mobility ◽  
Acid Content ◽  
Sialic Acid Content ◽  
Small Doses ◽  
Type 3 ◽  
Time Type

125I-labeled asialotransferrin types 1 and 2 were administered in small doses to rats. The protein still in the plasma after 1–12 h was partially repurified and electrophoresed at pH 8.1, together with a transferrin standard that is composed of all six forms of the protein with respect to sialic acid content. The electrophoretic mobility of both asialotransferrins increased with time, type 2 being affected sooner than type 1. The changed mobility was due to increased electronegativity that was fully reversible by treatment of the samples with neuraminidase, thus identifying the underlying cause as partial resialylation. Asialotransferrin incubated in vitro with serum, plasma, or whole blood for 16 h exhibited no change in electrophoretic mobility. In conjunction with an earlier study on asialotransferrin type 3, it was found that the apparent speeds of resialylation of the three asialotransferrins were in the same order as their affinities for the asialoglycoprotein-binding hepatic lectin. This suggests the involvement of an endo- rather than of an ecto-transferase. Transfer of 59Fe from asialotransferrins to the liver was used to monitor the frequency of hepatocyte–asialotransferrin interactions. Iron deposition in the liver took place much more rapidly than the appearance of detectable quantities of partially resialylated asialotransferrin molecules in the circulation. It is concluded that each asialotransferrin molecule probably undergoes several passages through the hepatocyte before its glycans become modified.

scholarly journals Quinine-dependent antibodies to neutrophils react with a 60-Kd glycoprotein on which neutrophil-specific antigen NB1 is located and an 85-Kd glycosyl-phosphatidylinositol-linked N-glycosylated plasma membrane glycoprotein

Blood ◽  
1993 ◽  
Vol 81 (10) ◽  
pp. 2758-2766 ◽  
Author(s):  
DF Stroncek ◽  
RA Shankar ◽  
GP Herr
Keyword(s):  
Plasma Membrane ◽  
Sialic Acid ◽  
Electrophoretic Mobility ◽  
Phorbol Myristate Acetate ◽  
Blood Cells ◽  
Specific Antigen ◽  
Membrane Glycoprotein ◽  
Myristate Acetate ◽  
Glycosyl Phosphatidylinositol ◽  
Drug Dependent

We have previously described a 24-year-old woman with quinine-dependent antibodies that reacted with neutrophils, red blood cells (RBCs), platelets, and T lymphocytes. The drug-dependent neutrophil antibody was found to react with 85- and 60-Kd neutrophil membrane molecules. In these studies, we further characterized these molecules and found that both were glycosyl-phosphatidylinositol (GPI)-linked and contained sialic acid residues and N-linked carbohydrate side chains, but neither contained O-linked carbohydrates. The protein backbone of the 60-Kd molecule was 45 Kd, and the 85 Kd glycoprotein (GP) was made up of 33- and 31-Kd proteins. While some GPI-anchored neutrophil GPs are released by stimulated neutrophils, neither the 85- nor the 60-Kd GP was released by neutrophil stimulated with C5a, f-met-leu-phe (FMLP), or phorbol myristate acetate (PMA). Neutrophil-specific antigen NB1 is located on a 58- to 64-Kd GP. To determine if the quinine-dependent antibody and anti-NB1 recognize the same GP, immunoprecipitation studies were performed with the quinine-dependent antibody using neutrophils with varying NB1 phenotypes. The 60-Kd GP was detected on NB1-positive neutrophils from 11 of 12 donors tested, but not on NB1- negative neutrophils from two donors tested. After solubilized 125I- labeled neutrophils were absorbed with anti-NB1, the quinine-dependent antibody immunoprecipitated the 85-Kd GP, but not the 60-Kd GP. These results indicate that anti-NB1 and the quinine-dependent antibody identified the same GP. The 85-Kd GP was detected on neutrophils from all 14 donors tested. The electrophoretic mobility of the 85-Kd GP was similar to the electrophoretic mobility of the major 125I-labeled neutrophil protein.

scholarly journals Role of sialic acid in erythrocyte survival

Blood ◽  
1975 ◽  
Vol 45 (1) ◽  
pp. 11-20 ◽  
Author(s):  
JR Durocher ◽  
RC Payne ◽  
ME Conrad
Keyword(s):  
Sialic Acid ◽  
Surface Charge ◽  
Electrophoretic Mobility ◽  
Polyacrylamide Gels ◽  
Membrane Glycoproteins ◽  
Atp Levels ◽  
Erythrocyte Survival ◽  
Pas Staining ◽  
Rapid Clearance

The role of membrane sialic acid in erythrocyte survival is unclear, although there is evidence for a reduction in sialic acid and surface charge in older erythrocytes. We reduced the surface charge of human, rat, and rabbit erythrocytes by removing sialic acid with neuraminidase.Reduction in sialic acid correlated with decreases in electrophoretic mobility and loss of PAS staining of membrane glycoproteins on polyacrylamide gels. No changes in ATP levels or deformability were found. 51Cr erythrocyte survivals in rats and rabbits showed rapid clearance of desialylated erythrocytes with sequestration by the liver.These results suggest that reduction in erythrocyte sialic acid is a mechanism of erythrocyte destruction and may be important in erythrocyte senescence.

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