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At least 1,279 records · Page 71Linked to original sources
PubMed1990

Effect of nicergoline on platelet aggregation, plasma viscosity and erythrocyte deformability in geriatric patients with cerebral infarction. Preliminary report.

The effects of nicergoline (Sermion) on platelet aggregation, plasma viscosity and erythrocyte deformability were evaluated in 11 geriatric patients with cerebral infarction, 2 men and 9 women (ages 61-78, mean age 71.6). Nicergoline was given orally at a dose of 5 mg 3 times daily after meals for 8 weeks. Hematological variables were determined twice prior to the administration and at 4 and 8 weeks after the administration. The platelet aggregation in vitro was determined by the turbidimetric method and the level of circulating platelet aggregates was determined according to the method of Wu-Hoak. Erythrocyte deformability was determined according to the method based on the examination of passing erythrocytes through a filter containing pores smaller than the undeformed cells. Collagen-, arachidonic acid- and PAF-induced platelet aggregation was decreased after nicergoline administration. Erythrocyte deformability was increased and plasma viscosity was also decreased after the administration. Thus the improvement of platelet aggregation, plasma viscosity and erythrocyte deformability in cerebral infarction may prevent disturbing blood flow and may contribute to prevention of formation and progression of thrombosis and atherosclerosis in geriatric patients with cerebral infarction.

Aged↗
PubMed1990

[Behavior of postoperative viscosity of bile fluid from T-drainage. A contribution to cholelithogenesis].

The results obtained by the examination of the post-operative bile viscosity behaviour sampled by T-drainages of 29 patients (investigations of the relative viscosity with the help of a modified horizontal capillary viscometer from the day of operation until the 9th postoperative day) confirm the importance of the biorheological classification of bile fluid as a Maxwell fluid (investigations of the absolute dynamic viscosity of 33 bile specimens with a Contraves-Low-Shear-Viscometer and representation of flow curves for rheological characterization). The Maxwell flow behaviour is characterized--among other things--by an exponential increase in the case of prestasis. This fact is important in all "low-flow-states" of different pathophysiological genesis and offers a concept with respect to a pathogenetically orientated cholelithiasis prophylaxis.

Adult↗
PubMed1989

[Dynamics of blood viscosity indices in patients with alcoholic myocardiodystrophy].

According to I. V. Strel'chuk's classification, 120 patients with alcoholic myocardiodystrophy induced by stage I-III chronic alcoholism were examined. The control group included 25 normal men. The rheological blood parameters (fluidity limit, apparent viscosity, red blood cell aggregation ratio, and hematocrit) were examined over time: before treatment, after its discontinuance, and one month after discharge from hospital. It was shown that blood viscosity increased with the disease gravity, whereas the results of the treatment correlated well with the initial patient's status. In stages I and II chronic alcoholism, the study parameters could return to normal, while in stage III, blood viscosity remained significantly higher than normal both towards the end of the treatment at hospital and on control examination one month after discharge. The control over blood rheology performed over time may be recommended as an additional method for assessing the disease gravity and efficacy of the treatment of alcohol-induced abnormalities.

Alcoholism↗
PubMedDate not supplied

[Interconnection of the composition, physico-chemical characteristics of lipids and viscosity of the nuclear membrane after administration of diazan (1,2-bis-diazoacetylethane) in vivo].

Studies were carried out of changes in lipids composition, their antioxidative activity (AOA) and oxidizability, as well as of the viscosity of different regions of the liver cells nuclear membrane after single injection of diasan (1,2-bis-diasoacetyletan) (class of diasoketones) possessing antitumor activity in the experiment. On the basis of the results obtained the state of membrane control system was analysed. In vivo injection of diasan was found to bring about changes in AOA--membrane viscosity interaction in the system as compared to the norm. These changes are due to distortion of AOA--lipids composition--oxidizability interaction at earlier times, and of lipids composition--membrane viscosity interaction at later times. The experimental data are discussed in terms of a theoretical model of functioning of this control system in response to stimulation. A number of hypotheses are advanced concerning the role of some interactions of the system for the cell metabolism in the norm and antitumor effect of diasan from the standpoint of the control system under consideration.

Animals↗
PubMedDate not supplied

[Effect of medium viscosity on the activity of myosin ATPase].

The influence of increased medium viscosity on the activity of myosin Ca2+-ATPase has been studied in 28, 45 and 60% water-sucrose solutions at 25 degrees C. In the wide range of viscosities (10 divided by 430 mp) the rate constant of ATP hydrolysis displays the negative power-law dependence on solution viscosity with an index approximately -0,5. The obtained data confirm an idea about the existence of direct connection between the low-frequency liquid relaxations and structural dynamics of proteins and enzymes.

Adenosine Triphosphatases↗
PubMed1987

The increase in viscosity and peroxidation of sarcoplasmic reticulum membrane lipids in isadrine myocarditis.

The viscosity of membranes isolated from sarcoplasmic reticulum of rabbits with isadrine myocarditis was studied, using pyrene as a hydrophobic fluorescent probe. The increase in the viscosity of membranes from injured heart occurred at lower temperatures and was sharper than in the case of intact heart in both "free" and "bound" lipid domains. The increase in the lipid viscosity under myocarditis was associated with decreased Ca++, Mg++ -ATPase and cAMP-dependent protein kinase activities and with an elevated content of lipid peroxidation products.

Animals↗
PubMed1986

[Interrelation between the natural antioxidant content and lipid viscosity in normal organelle membranes].

Two systems regulating lipid peroxidation (LP) natural antioxidants and structural organization were studied in the liver mitochondria, microsomes and nuclear membranes, using chemiluminescent and spin labelling techniques. Mitochondrial lipids were most protected against LP and were characterized by the maximum content of effective antioxidants and high viscosity. Nuclear lipids were the least protected against the systems studied and had lower antioxidant efficiency and viscosity. Direct correlation between the content of natural antioxidants and lipid viscosity was established.

Animals↗
PubMed1987

[Whole blood viscosity in patients with acral arterial occlusive diseases and their modification by rheologically active drugs].

Measurements of the whole-blood viscosity in patients with organic and functional disturbances of the acral blood supply were performed. In comparison with the whole-blood viscosity in normal persons patients with acral occlusive diseases showed a significantly increased viscosity. On the other hand, in patients with functional disturbances of the acral blood supply no differences could be established. In a therapy study the good efficacy of rheologically effective medicaments could be demonstrated particularly as combination therapy of pentoxifylline, acetylsalicylic acid and tolazoline in patients with acral occlusive diseases. These medicaments should by all means be used together with the basic therapy. In functional disturbances of the blood supply should predominantly be maintained physiotherapeutic methods of treatment.

Adult↗
PubMed1987

[Effect of phenothiazines on the viscosity and electrical stability of model phospholipid membranes].

The effect of five phenothiazine derivatives on the viscosity of model phospholipid membranes (by eximerization of pyrene) and on their electrical stability has been studied All the phenothiazines tested (chlorpromazine, propazine, triftazin and nonachlazine), except for chloracyzine, considerably increase the viscosity of phospholipid liposome bilayer at a concentration of 10(-5)-10(-4) M. Phenothiazines have been also shown to decrease liposome break-down potential even at a concentration of 10(-7) M. No correlation between the magnitude of break-down potential and changes in liposome membrane viscosity has been revealed.

In Vitro Techniques↗
PubMed1987

Blood viscosity in primary open-angle glaucoma.

To determine whether hemorrheologic factors play a part in optic nerve cupping and visual field loss in glaucoma, blood viscosity was measured at three shear rates in 27 patients with primary open-angle glaucoma and 18 healthy control subjects matched for sex, mean arterial blood pressure and smoking habits. The study was conducted between 1984 and 1986. The mean viscosity was significantly higher in the glaucoma group than in the control group at all three shear rates. The possible relevance of raised blood viscosity as a causal factor in optic nerve cupping in patients with glaucoma is discussed.

Aged↗
PubMed1986

Increased blood viscosity in diabetic proliferative retinopathy.

Blood rheology and haemostasis were assessed in 18 diabetics with proliferative retinopathy and in 18 diabetics without proliferative retinopathy, matched for age, sex, smoking habit and type, duration and treatment of diabetes. Proliferative retinopathy was associated with significantly higher levels of blood viscosity at high and low shear rates, which were related to higher levels of plasma viscosity and fibrinogen. Blood urea, glucose, glycosylated haemoglobin and white cell count were also significantly higher, whereas haematocrit, red cell deformability and several other haematological and biochemical variables did not differ significantly in the 2 groups. In view of these findings, and of our recent demonstration that increased blood viscosity also exists in those patients with retinal vein occlusion who develop a similar proliferative retinopathy, we suggest that hyperviscosity may contribute to retinal ischaemia and hence proliferative retinopathy.

Adult↗
PubMed1985

[Various plasma components and whole blood viscosity in patients with the vascular form of vibration disease].

In 82 men suffering from vascular form of the vibration disease, divided by the degree of its advancement into two groups: I--consisting of 42 persons (average age 40 +/- 7,5 years) at an early stage of the disease and II--consisting of 40 persons (average age 49.7 +/- 5.6 years) with an advanced stage of the disease--the whole blood and plasma viscosity, the plasma fibrinogen level, the total protein level and its fractions and the total cholesterol level were determined. The control group (III) consisted of 100 men in good health (average age 41.3 +/- 8.4 years). The studies showed in both groups with the disease a significant growth of alpha 1, gamma globulins and fibrinogen. It was demonstrated that the increased blood viscosity is--among other things--a consequence of increased plasma viscosity and proteins disturbances.

Blood Proteins↗
PubMed1985

Effects of meal viscosity on serum gastrin response and gastric emptying rate in duodenal ulcer patients.

Addition of guar gum to a meal increases its viscosity. Two test meals of differing viscosities were eaten by 15 duodenal ulcer patients. Gastric emptying rates were measured over 120 minute periods after ingestion of the meals by determining the intragastric content of the polyethylene glycol which had been included in the meals. Serum gastrin levels were determined over the same period by radioimmunoassay. The gastric emptying rate was significantly (p less than 0.05) lower after the meal of higher viscosity, but there were no significant differences in serum gastrin levels at any time of measurement after the two meals.

Adult↗
PubMed1985

Effects of thermal adaptation at 40 degrees C on membrane viscosity and the sodium-potassium pump in Chinese hamster ovary cells.

We have demonstrated increased heat resistance in Chinese hamster ovary cells grown to confluence at 37 degrees C and thermally adapted at the nonlethal temperature of 40 degrees C for 24 h. Membrane viscosity, estimated by fluorescence anisotropy, was inversely related to temperature, from 5 degrees C to 45 degrees C. For a given temperature viscosity was consistently higher in thermally adapted cells than in native cells. Having demonstrated a change in membrane structure associated with thermal adaptation, we carried out a study of the Na+-K+ pump in native and thermally adapted cells as an example of a vital active transport process known to be sensitive to membrane viscosity. 86Rb uptake measured from 31 degrees C to 50 degrees C increased steadily to 46 degrees C and then decreased rapidly in both native and thermally adapted cells. Detailed measurement of ouabain-sensitive 86Rb influx demonstrated an increase in both Km and Vmax between 37 degrees C and 45 degrees C, but there was no difference between native and thermally adapted cells. We have thus demonstrated an adaptive structural change in the cell membrane of mammalian cells which may be related to the induction of thermal resistance at 40 degrees C but which is not associated with any change in this active transport system.

Adaptation, Physiological↗
PubMed1985

[Evaluation of blood viscosity and erythrocyte filterability in chronic ischemic heart disease].

In 40 patients suffering from chronic ischemic heart disease (16 with history of myocardial infarction, 10 with unstable angina and 14 with stable angina) and in an equal number of sex-and age-matched control subjects, we have determined plasma and blood viscosity according to RAND et al. using a Wells-Brookfield Micro-Viscometer, shear rate 230 sec-1, and red cell filterability according to REID et al. Significant differences were found in patients suffering from ischemic heart disease, in comparison with the control group, for blood viscosity (p less than 0.01), plasma viscosity (p less than 0.001) and red cell filterability (p less than 0.001). The changes of hemorheological parameters in ischemic heart disease, especially in patients suffering from unstable angina and in those with history of myocardial infarction, point to the opportunity of a pharmacological treatment aiming at improving the district microcirculation.

Adult↗
PubMed1985

[Method for evaluating sputum viscosity].

Continuing a study on mucolytically and secretolytically effective drugs, a viscometrically energetic principle was designed for controlling both the virtual viscosity and the adhesion of sputum. The technique used is integral in character, an amount of 2 to 4 ml of inhomogeneous purulent and foam-free sputum being sufficient for the purpose. The data are shown in a curve the characteristic of which is a piecewise e-function giving separate descriptions of the virtual viscosity and the adhesive behaviour. The curves are used to record the progress of the therapy used. "Technique and device for measuring viscosity" was registered at the Amt für Erfindungs- und Patentwesen der DDR HA Rechtsschutz in 1984 (WP G 01 N/251 817 5) the authors being Scheuler, Fischer and Felgenhauer. Details are given in.

Expectorants↗
PubMed1985

[Blood viscosity and the pressure limit of whole blood in patients with a vascular form of vibration disease].

Eighty-two men suffering from the vascular form to the vibration disease have been divided into two groups pursuant to advancement of the disease: group I consisting of 42 persons (average age 40 +/- 7.5 years) representing an early stage of the disease, and group II consisting of 40 persons (average age 49,7 +/- 5,6 years)--at an advanced stage of the disease. In both groups the variation of apparent viscosity with shear rate (rheological equations), plastic viscosity and yield stress of the whole blood have been determined. The control group consisted of 100 healthy men (average age 41.3 +/- 8.4 years), classified as medium-hard working (group III). Those afflicted with the vascular form of the vibration disease have been found to exhibit viscosity and yield stress of the whole blood, the increase varying with advancement of the disease.

Adult↗
PubMed1979

[The clinical significance of blood viscosity in degenerative angiopathies].

During an examination of a group of 63 patients with chronic ischaemic heart disease and condition after myocardial infarction the viscosities measured with the help of a rotation viscosimeter lay clearly above the values of good reference persons. There were positive correlations of the blood viscosity to the haematocrit value, fibrinogen level, globulin content as well as to the total protein, total lipid and cholesterol level. In the transition to the logarithm of the viscosity the measure for the linear dependence with the exception of the total protein level became smaller. A formation of partial correlation coefficients by means of the exclusion of the haematocrit in every case resulted in increasing coefficients r for the investigated parameters of the lipid metabolism cholesterol, total lipids and triglycerides.

Blood Proteins↗