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PubMed1983

[Clinico-experimental studies on blood viscosity].

After their preponderated surgical treatment by 144 patients have been taken the blood-viscosity in dependence of some physiological and pathophysiological parameters after infusion of infucoll 6%. We have used for these compared examinations the rheo-viscometer after Höppler. So we succeeded in proving the relationship between increased blood-viscosity, maligne tumour sufferings, and illness of the respiratory system. The results of the infucoll preparation are - with regard to the coagulation, hindrance of thrombocyte aggregations, and viscosity reduction - to qualify as discreet, showing more regulating character.

Adolescent↗
PubMed1983

Studies of blood viscosity with a newly constructed rotational viscometer which operates via a desk top computer.

Increasing interest is being shown in blood viscosity and the whole field of haemorheology. This study presents a newly constructed rotational Couette type viscometer which operates via a commercially available desk top computer and a digital plotter. The influence of haematocrit on blood viscosity is shown and the study also presents blood viscosity values of six to eight healthy men at 24 degrees C and 37 degrees C. At 37 degrees C values are shown both at natural haematocrit and at haematocrit 45%.

Blood Viscosity↗
PubMed1983

[Blood viscosity and erythrocyte deformability in diabetic retinopathy].

The whole blood and plasma viscosity, hematocrit and plasma fibrinogen were studied in 26 diabetic patients (11 with and 15 without retinopathy) and in 25 non-diabetic control subjects. Blood viscosity, plasma viscosity and plasma fibrinogen were significantly higher in diabetics than in controls, but no significant differences were found when diabetics with retinopathy were compared to diabetics without retinopathy. The red cell deformability was significantly reduced in diabetics if compared with that of controls; the statistical significance of this reduction was confirmed only in the group of diabetics with retinopathy, but failed when the group of diabetics without retinopathy was considered.

Adult↗
PubMed1983

[Effect of hexobendine and pentoxifylline on the viscosity of erythrocyte suspension].

The effect of hexobendine, pentoxifylline and of the combination Instenon, containing hexobendine, on the dynamic viscosity of blood-isotonic and hyperosmolal suspensions of human and rat erythrocytes was studied. Hexobendine caused a statistically significant reduction of viscosity beginning at 10(-4) M, under hyperosmolal conditions even at 10(-5) M. Instenon was somewhat less active than hexobendine alone at a concentration equivalent to its presence in Instenon. Pentoxifylline did not decrease the viscosity under the selected conditions. The effect of hexobendine is considered due to an increase of red cell flexibility, probably caused by an elevation of the ATP content or by an alteration of the membrane structure of the erythrocytes.

Animals↗
PubMed1983

[Changes in blood viscosity after administration of vitamin E in the rabbit].

Vitamin E is an essential factor to maintain biological membranes stability and its lack may affect membranes structures and reduce erythrocyte life-span. Vitamin E also play a role in the maintenance of a normal platelet aggregation. A.A. studied the effects of a ten days supply of d-1-alpha tocopherol acetate (50 mg/Kg/die) on blood viscosity in 8 rabbits. Results obtained show a significant reduction of blood viscosity on 6th day of treatment in the male rabbits and a progressive reduction of values from the 6th till the 10th day in female rabbits. The most significant decrease of blood viscosity were obtained at the lowest shear-rates, due to an increased red cells deformability to the antioxidative action of vitamin E on the erythrocytes membrane and to a reduced red cells aggregation. Such modifications on the red blood cells caratheristics can be determined by vitamin E through different mechanism: a) inhibiting red cell membrane's polyunsaturable fatty acids oxidation; b) by removal of abnormal lipids from erythrocyte membrane; c) physical and chemical stabilization of membrane's surface.

Animals↗
PubMed1982

Modifications of embedding tissues in durcupan ACM (Fluka) based on viscosity index measurements.

Viscosity of Durcupan ACM mixtures without as well as with accelerator was measured, at temperatures of 25, 40, and 50 degrees C respectively. The time course of polymerization was expressed within first few hours following admixture of accelerator, at temperature mentioned above. On the basis of our findings a modified embedding schedule for tissues (peripheral autonomic nerves and ganglia) has been recommended: infiltration in Durupan 1 (without accelerator) could be performed at 50 degrees C, when viscosity of embedding mixture is greatly reduced, to 190 mPa. s. Further infiltration in Durcupan 2 (with accelerator added) is carrier out at 40 degrees C; the initial viscosity of embedding medium at this temperature is 440 mPa. s. and even after 4 hours it keeps below 200 mPa. s. So the infiltration time could be prolonged in contrast to that at 50 degrees C, which usually brings better embedded blocks and better ultrathin sections.

Animals↗
PubMed1982

Increased blood viscosity in a patient with sickle cell anemia.

Although intracellular viscosity is greatly increased in deoxygenated sickle cells, the viscosity of blood is not, because patients' packed cell volumes (PCV) are usually extremely low (15-25%). A young women with sickle cell anemia was admitted with a typical painful crisis, and was found to have a PCV of 39% with a reticulocyte count of 3.6%. During a hospitalization of 48 h, the PCV rose to 46%; her pain subsided but her behavior became bizarre, cardiopulmonary arrest occurred, and she could not be resuscitated. At autopsy, no abnormalities were found except for congested blood vessels containing sickle cells. It was subsequently discovered that she and her family had been exposed to carbon monoxide for a week prior to admission. Blood samples from another patient studied with a PCV of 40% showed progressively decreased viscosity if they contained 13-20% carboxyhemoglobin. It is suggested that preexisting accelerated erythropoesis was further stimulated by CO, and caused "compensatory polycythemia", but that the CO prevented most of the newly formed cells from sickling and being destroyed. Admission to hospital caused a gradual disappearance of CO but the patient's PXV continued to rise. Her death may have been due to a rare form of hyperviscosity syndrome, when the level of carboxyhemoglobin in her blood fell to more normal levels and her cells regained the ability to sickle. Treatment of sickle cell anemia with an effective non-covalently bound agent could have a similar effect, if the agent were withdrawn abruptly.

Acute Disease↗
PubMed1981

Selectively aspirated pure pancreatic secretion. Viscosity, trypsin activity, protein concentration and lactoferrin content of pancreatic juice in chronic pancreatitis.

The viscosity, trypsin activity, protein concentration and lactoferrin concentration in selectively aspirated, pure pancreatic secretion uncontaminated by bile, were determined in 46 patients with chronic pancreatitis and compared with the values obtained in 39 control subjects. The viscosity was measured using a modified capillary viscosimeter, the trypsin activity and the protein concentration using photometry, and the concentration of lactoferrin employing a new standard. It was found that in chronic pancreatitis, viscosity, trypsin activity and lactoferrin concentration was also found to be increased, but the differences were not significant. The results of this examination support the hypothesis that precipitation of protein-containing material in the pancreatic ducts, delayed outflow of secretion and premature activation of trypsin are pathogenically important factors in chronic pancreatitis.

Adult↗
PubMed1981

[Effect of incorporation and removal of cholesterol on the lipid bilayer viscosity and the rate of oxidative reactions in rat liver microsomal membranes].

The interrelationship between the lipid bilayer viscosity and the rate of oxidative reactions in rat liver microsomal membranes were investigated. The viscosity of the lipid bilayer is increased upon incorporation of cholesterol into the microsomes and is decreased upon its removal. This results in a corresponding decrease and increase of the rate of cytochrome b5 reduction by NAD(P)H. The rates of cytochrome P-450 reduction and oxidation of dimethylaniline, aniline, p-nitroanisol and NAD(P)H, as well as those of oxygen uptake and lipid peroxidation do not depend on the bilayer viscosity. Hence only the reactions of cytochrome b5 reduction by NADH- and NADPH-specific flavoproteins are diffusion-dependent processes in the microsomal oxidation chain.

Animals↗
PubMed1978

[Study of blood viscosity and fibrinogen as a guide to the therapy of atherosclerotic peripheral arteriopathy].

Of the many blood parameters now regarded as useful in the study of arteriopathy particular importance is attached to viscosity and fibrinogen levels. Changes in viscosity lead to changes in flow and the supply of O2 to the tissues, while fibrinogen alterations frequently accompany or precede atherosclerosis, since they both encourage the intravascular deposition of fibrin and help to modify viscosity. The pharmacological correction of such changes is discussed.

Adult↗
PubMed1978

[Effect of Na+ and Ca++ ion concentrations in the outer medium surrounding the erythrocyte membrane on the viscosity of blood suspensions].

A small concentration of Na+ ions (0.1 mM) causes an enlargement of the viscosity in suspensions of erythrocytes which is partial reversible by addition of Na+ ions. Ca++ ions have a conserving function. The relative viscosity is changed in the relation of concentrations of ions of Ca++:Na+ = 1:2. Changes in the viscosities are refered to change of structure of the components of membrane, especially for the part of lipids.

Blood Viscosity↗
PubMed1994

Comparing conformations at low temperature and at high viscosity. Conformational study of somatostatin and two of its analogues in methanol and in ethylene glycol.

The influence of low temperature and high viscosity on the conformation of somatostatin and two of its analogues was investigated by 1H NMR in solution. The conformation of native somatostatin, a cyclic octapeptide agonist DC13-116 and a linear octapeptide agonist were compared in ethylene glycol at 303 K and in methanol at low temperature. The first goal of this study was to investigate if either low temperature or high viscosity is the more important for the reduction of the conformational freedom. Secondly we wanted to compare the amount of information concerning the conformation present in both solvents. A larger amount of NOESY cross-peaks is observed in ethylene glycol at room temperature compared to methanol at low temperature. This indicates that the raising of the viscosity is a more important factor in reducing the flexibility of peptides than the lowering of the temperature.

Amino Acid Sequence↗
PubMed1976

Effect of bromhexine and guaiphenesine on clinical state, ventilatory capacity and sputum viscosity in chronic asthma.

Thirty-four patients, 21 male and 13 female, with chronic asthma and tenacious mucoid expectoration were studied regarding clinical parameters, PEF, airway resistance and sputum viscosity measured according to the n.m.r. method (nuclear magnetic resonance); a technique for determination of the water phase viscosity. Using double-blind cross-over technique, oral treatment with the two drugs and placebo was given during three consecutive 12-day periods with 48-h intervals free of test drug. No significant improvement in clinical state, PEF or airway resistance could be demonstrated. Nor did the sputum viscosity show any significant change after treatment with the different preparations. However, regarding the patients' own preference of drug as to mucolytic effect, a significant difference in favour of bromhexine at the 0.1% level was shown.

Airway Resistance↗
PubMedDate not supplied

Low density lipoprotein cholesterol and whole blood viscosity.

Whole blood viscosity (WBV) was measured in a normal population and was analyzed in relation to packed cell volume, (hematocrit, PCV), fibrinogen, white blood cell count (WBC), platelet count, and plasma lipids, including total cholesterol, triglycerides, high density lipoprotein cholesterol (HDLc) and low density lipoprotein cholesterol (LDLc). Conventional assays were used for all blood and lipid measurements. Whole blood viscosity was measured under disaggregating conditions with a disposable, porous bed viscometer. As expected, the strongest correlation was seen between WBV and PCV (r = 0.78, p < 0.001). Significant positive correlations also were demonstrated between WBV and cholesterol (r = 0.22, p < 0.001), triglycerides (r = 0.14, p < 0.001) and LDLc (r = 0.21, p < 0.001). A significant negative correlation was found between HDLc and WBV (r = -0.20, p < 0.001). Correlation analysis by sex showed only the correlation of LDLc was significant for both men and women. A stepwise multiple regression analysis of WBV indicated that LDLc, fibrinogen (Fbg) and platelet (Plt) counts correlated independently of PCV to WBV. The equation derived from multiple regression and partial correlation analysis was: WBV (mPa.sec) = -9.317 + 0.0047 (LDLc) + 0.381 (PCV) + 0.00152 (Plt) + 0.0021 (Fbg). The calculated mean specific contribution of PCV was 90.8 percent, LDLc 3.5 percent, and fibrinogen 3.3 percent to observed mean WBV. This study shows that LDLc is the principal lipoprotein independently influencing whole blood viscosity and its effect is similar in magnitude to fibrinogen. Further studies to elucidate the mechanism and clinical significance of the effects of LDLc on WBV are indicated.

Adult↗
PubMed1994

Dithiothreitol effects on the viscosity and quality of human semen.

OBJECTIVE: To determine the effects of treatment with dithiothreitol (DTT) on seminal viscosity, consistency, and sperm motility, motion characteristics, and morphology. DESIGN: Prospective, in vitro study. SETTING: University teaching hospital. PATIENTS: Semen donors and patients of the infertility program. Experiment 1, n = 34; experiment 2, n = 82. Sufficient seminal volume for use was the only selection criterion. INTERVENTIONS: Experiment 1: semen was combined with 5.9 mM DTT solution 1:1 (vol/vol), combined with distilled water 1:1 (vol/vol), or untreated. Experiment 2: semen was combined with 5.9 mM DTT solution 1:1 (vol/vol) or untreated. MAIN OUTCOME MEASURES: Seminal consistency and viscosity, percentage of motile sperm, sperm motion characteristics (straight line velocity, curvilinear velocity, mean linearity, and angle of lateral head displacement), sperm concentration, and sperm morphology. RESULTS: Treatment of semen with DTT reduced seminal consistency and viscosity. Treatment with DTT had no effect on sperm concentration or percentage motile sperm. Sperm velocity was reduced by DTT treatment, particularly in semen that had normal initial consistency. Morphology of sperm in semen exhibiting abnormal initial consistency was unaffected by DTT. CONCLUSION: Dithiothreitol effectively induced liquefaction of nonliquefied semen in vitro and had minimal effects on the sperm motility, motion characteristics, and morphology. Evaluation of DTT effects on the chromatin and on other functional traits of human sperm must be conducted before its use can be advocated.

Dithiothreitol↗
PubMed1975

[Clinical significance of changes in blood viscosity in cerebrovascular insufficiency (author's transl)].

In 50 patients with encephalomalacia and 50 patients with a transient cerebral ischemic attack (TIA) the risk factors and viscosity of the whole blood as well as the hematocrit were determined before the start of treatment. Compared to a control group, the blood viscosity in patients with encephalomalacia was significantly increased (p less than 0.001) in all ranges of shearing velocity tested, in patients with TIA only at that shearing velocity which may be assumed for the area of microcirculation. This increase was related to the presence of arterial hypertension, hyperlipemia, heart failure, diabetes mellitus, hyperfibrinogenemia and increased tendency of thrombocytes and erythrocytes to aggregate. From the results obtained it was concluded that increased blood viscosity in the cerebral area of microcirculation with insufficient cerebral collateral circulation may decisively favor the development of encephalomalacia.

Acute Disease↗
PubMed1993

[Gastric mucosal blood flow and blood viscosity in patients with diabetes].

For the study of the microcirculatory disturbance of the digestive tract in patients with diabetes, 41 cases with non-insulin dependent diabetes mellitus (NIDDM) were selected (mean age 53.9 Yrs., 22 male/19 female). Of these patients 9 were without complication, and 32 with complications. Gastric mucosal blood flow (GMBF) was determined at 14 points of laser and greater curvature, anterior and posterior wall of antrum, angle and corpus of stomach, pylorus and anterior wall of duodenum with laser Doppler flowmetry (PF2). Results showed that the mean value of the 14 points of GMBF in 41 patients with NIDDM was 2.81 +/- 0.15(V, mean +/- s mean), which was significantly lower than that of 11 normal subjects (4.77 +/- 0.29V, P < 0.001). The mean GMBF of 8 cases of NIDDM without gastric disease was 2.92 +/- 0.28V, which was also lower than that of normal control (61.2% of normal value, P < 0.001). The GMBF in 27 cases of diagnosed chronic superficial gastritis (CSG 2.79 +/- 0.15V) was lower than the GMBF of 63 CSG patients without NIDDM (3.23 +/- 0.12V, P < 0.05). The viscosity of blood and plasma was determined with NAAKE viscometer in 26 patients with NIDDM. It was found that the blood viscosity was significantly higher than that of the normal control, and the plasma viscosity was also increased but without statistic significance. Results showed that the GMBF of NIDDM was significantly lower than that of the normal subjects or CSG patients without diabetes. It implied that the visceral microcirculatory disturbance also involved the digestive system leading to the GMBF decrease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

[Effects of oxyfedrine on high blood viscosity and myocardial necrosis induced by epinephrine and ice water stress in rats].

Acute high blood viscosity (HBV) and myocardial necrosis was established by epinephrine (Epi) and ice water stress in rats. Effects of iv oxyfedrine (Oxy) on HBV, plasma viscosity (PV), hematocrit, erythrocyte electrophoretic time (EET), and fibrinogenic viscosity (FV) were studied in model. Results showed that Oxy 1 mg.kg-1 iv markedly decreased the arterial and venous blood HBV at shear rates of 700 s-1 and 70 s-1, respectively (P < 0.01). There were significant differences in the alleviation of HBV among 3 groups (Oxy 0.01, 0.1, and 1 mg.kg-1 iv). The above doses markedly decreased the HBV, PV, and FV, and shortened the EET. Effects of iv Oxy on the myocardial necrosis rat model were scrutinized under the light and electron microscopes. Oxy iv 1 mg.kg-1.d-1 x 1, 3, and 5 d prevented or mitigated the occurrence and development of myocardial necrosis. The structure of heart mitochondria and myofibrils were clearly discernible. This action may be related to the alleviation of HBV by Oxy.

Animals↗