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Blood Viscosity (blood + viscosity)
Kinds of Blood Viscosity Selected AbstractsPhysical Model-Based Indirect Measurements of Blood Pressure and Flow Using a Centrifugal PumpARTIFICIAL ORGANS, Issue 8 2000Tadashi Kitamura Abstract: This article describes a technique offering indirect measurements of pump pressure differential and flow with certain accuracy independent of changes in blood viscosity. This technique is based on noninvasive measurements of the motor current and rotation speed using the physical model equations of the centrifugal pump system. Blood viscosity included in the coefficients of the dynamic equations is first estimated, and then substitution of the estimated viscosity into the steady equations of the model provides pump flow and pressure differential. In vitro tests using a Capiox pump showed a sufficient linear correlation between actual values and their estimates for pressure differential and pump flow. An in vivo test using a 45 kg sheep showed that the proposed algorithm needs robustness for the convergence of estimates of viscosity. An overall evaluation, however, of the developed algorithm/model showed indications of success in terms of efficient computation and modeling. [source] Mechanisms of fibrinogen-induced microvascular dysfunction during cardiovascular diseaseACTA PHYSIOLOGICA, Issue 1 2010D. Lominadze Abstract Fibrinogen (Fg) is a high molecular weight plasma adhesion protein and a biomarker of inflammation. Many cardiovascular and cerebrovascular disorders are accompanied by increased blood content of Fg. Increased levels of Fg result in changes in blood rheological properties such as increases in plasma viscosity, erythrocyte aggregation, platelet thrombogenesis, alterations in vascular reactivity and compromises in endothelial layer integrity. These alterations exacerbate the complications in peripheral blood circulation during cardiovascular diseases such as hypertension, diabetes and stroke. In addition to affecting blood viscosity by altering plasma viscosity and erythrocyte aggregation, growing experimental evidence suggests that Fg alters vascular reactivity and impairs endothelial cell layer integrity by binding to its endothelial cell membrane receptors and activating signalling mechanisms. The purpose of this review is to discuss experimental data, which demonstrate the effects of Fg causing vascular dysfunction and to offer possible mechanisms for these effects, which could exacerbate microcirculatory complications during cardiovascular diseases accompanied by increased Fg content. [source] Decreased red blood cell aggregation subsequent to improved glycaemic control in Type 2 diabetes mellitusDIABETIC MEDICINE, Issue 4 2003B. Chong-Martinez Abstract Aims Reports of rheological changes following intensification of metabolic control are limited and not concordant. The present study was designed to test the hypothesis that intensification of management of Type 2 diabetes (T2DM) with diet, exercise and insulin improves haemorheological behaviour by reducing red blood cell (RBC) aggregation. Methods Blood was sampled from 55 subjects before and following 14 ± 3 weeks of intensified management. RBC aggregation was measured in vitro for cells in plasma or in an aggregating 70 kD dextran solution. Plasma viscosity and whole blood viscosity were also measured. Results During treatment, fasting glucose fell 27%, HbA1c fell 21%, and serum triglycerides and total cholesterol fell 28% and 12%, respectively (P < 0.0001 for each). The extent and strength of RBC aggregation in plasma fell by 10,13% (P < 0.002). Similar decreases of RBC aggregation were seen for cells suspended in dextran (P < 0.002). Plasma viscosity decreased by 3% (P < 0.02) and high shear blood viscosity by 6,7% (P < 0.0001). Changes of RBC aggregation in plasma and in dextran were significantly correlated, supporting a cellular rather than a plasmatic origin for these changes. However, there were no significant correlations between RBC aggregation changes and changes of fasting glucose, HbA1c, serum triglycerides, serum cholesterol, or plasma fibrinogen. Conclusions Intensified metabolic control results in a reduction of RBC aggregation that appears to be intrinsic to RBC. Since increased RBC aggregation can impair microcirculatory flow, it is possible that haemorheological factors may contribute to the reduction of microvascular complications resulting from improved metabolic control in T2DM. [source] Effects of phlebotomy on haemodynamic characteristics during exercise in Standardbred trotters with red cell hypervolaemiaEQUINE VETERINARY JOURNAL, Issue 4 2001P. FUNKQUIST Summary Five Standardbred trotters with red cell hypervolaemia (RCHV) were compared before and after removal of approximately 22% (36 ml/kg bwt) of the total blood volume in order to evaluate the haemodynamic responses, haemorheological alterations and oxygen transport during exercise to fatigue. Data were recorded during submaximal exercise at 4 different speeds on a treadmill and then during continued running at the highest speed step until fatigue. Oxygen uptake (V,O2), pulmonary artery pressure (PAP), systemic artery pressure (SAP), heart rate (HR), haematocrit and haemoglobin concentrations (Hb) were measured. Arteriovenous O2 content difference (C(a-v,)O2), pulmonary vascular resistance (PVR) and total systemic resistance (TSR) were calculated. Whole blood and plasma viscosity and erythrocyte aggregation tendency were determined with a rotational viscometer. Endoscopy was performed after exercise. ANOVA was used for statistical analysis. Phlebotomy resulted in a decrease in haematocrit and Hb during the course of exercise. Blood and plasma viscosity were lower and erythrocyte aggregation tendency was higher after phlebotomy. Throughout exercise, including submaximal work and continued running to fatigue, PAP, SAP, PVR, TSR and C(a-v,)O2 were lower after phlebotomy. HR was higher after phlebotomy during submaximal exercise. Oxygen delivery and VO2 were lower after phlebotomy in the period from submaximal exercise to fatigue. Run time to fatigue was shorter after phlebotomy. Four horses showed exercise-induced pulmonary haemorrhage (EIPH) before phlebotomy and the degree of bleeding was diminished but not abolished after phlebotomy. The reductions in PVR, TSR, PAP and SAP after phlebotomy were probably a result of reduced blood viscosity. In conclusion, although a 22% reduction in blood volume improved the haemodynamic and haemorheological parameters and the degree of EIPH, it was found that RCHV trotters have to rely on high oxygen delivery to the working muscles for maintenance of maximal performance. [source] Haemorheology in Gaucher diseaseEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 3 2005Bridget E. Bax Abstract:, In Gaucher disease, a deficiency of glucocerebrosidase results in the accumulation of glucocerebroside within the lysosomes of the monocyte,macrophage system. Prior to the availability of enzyme replacement therapy (ERT), splenectomy was often indicated for hypersplenism. Haemorheological abnormalities could be expected in view of the anaemia and abnormal lipid metabolism in these patients and the role of the spleen in controlling erythrocyte quality. Objectives: To investigate the effect of Gaucher disease on blood and plasma viscosity, erythrocyte aggregation and erythrocyte deformability, and to determine whether observed rheological differences could be attributed to splenectomy. Methods: Haematological and haemorheological measurements were made on blood collected from 26 spleen-intact patients with Gaucher disease, 16 splenectomised patients with Gaucher disease, 6 otherwise healthy asplenic non-Gaucher disease subjects and 15 healthy controls. Results: No haemorheological differences could be demonstrated between spleen-intact patients with Gaucher disease and the control group. Compared to controls, both asplenic Gaucher disease and asplenic non-Gaucher disease study groups had a reduced MCHC (P = 0.003 and 0.005, respectively) and increased whole blood viscosity at 45% haematocrit (Hct), relative viscosity and red cell aggregation index , all measured at low shear (P < 0.05 for all). Additionally, asplenic patients with Gaucher disease alone showed an increased MCV (P = 0.006), an increased whole blood viscosity at 45% Hct measured at high shear (P = 0.019), and a reduced relative filtration rate (P = 0.0001), compared to controls. Conclusion: These observations demonstrate a direct and measurable haemorheological abnormality in Gaucher disease only revealed when there is no functioning spleen to control erythrocyte quality. [source] Improved treatment of sudden hearing loss by specific fibrinogen aphaeresisJOURNAL OF CLINICAL APHERESIS, Issue 2 2004Heidrun Ullrich Abstract The etiology of sudden sensorineural hearing loss is still unclear and is thought to result from disturbances of microcirculation, infectious causes, or autoimmune disorders. So far standard therapy did not show clear improvement over spontaneous remission rate, which is assumed to be about 50% [Nakashima et al., Acta. Otolaryngol. Stockh. 514:14,16, 1994; Schuknecht and Donovan, Arch. Otorhinolaryngol. 243:1,15, 1986; Harris and Sharp, Laryngoscope 100:516,524, 1990; Mayot et al., Clin. Immunol. Immunopath. 68:41,45, 1993; Gussen, Ann. Otol. Rhinol. Laryngol. 85:94,100, 1976]. Elevated blood viscosity due to high fibrinogen levels is supposed to cause decreased cochlear blood flow and thus initiate sudden hearing loss. The specific lowering of fibrinogen immediately decreases plasma viscosity exactly to the desired extent and should lead to improved cochlear blood flow [Suckfüll et al., Acta. Otolaryngol 119:763,766, 1999; Suckfüll, Lancet 360:1811,1817, 2002; Walch et al., Laryngol. Rhino. Otol. 75:641,645, 1996; Suckfüll et al., Otol. Neurotol. 23:309,311, 2002]. In a prospective uncontrolled pilot study on 36 patients with unilateral sudden onset sensorineural hearing loss (SHL) we tried to establish that 1,3 specific fibrinogen aphaereses alone improve recovery of hearing and that it is possible to lower fibrinogen to the target of 80,100 mg/dl without important side effects. Pure tone audiometry was carried out immediately before and after each aphaeresis as well as at 2 and 4 weeks and 6 months after treatment. Sixteen patients recovered spontaneously before undergoing fibrinogen adsorption. All 20 aphaeresis patients improved during immunoadsorption; in 60% of patients auditory thresholds returned to normal after the first immunoadsorption and treatment could be discontinued, in another 20% of patients complete recovery was reached after 4 weeks. The mean plasma fibrinogen concentration of the 20 patients before the first aphaeresis session was 308.1 ± 51.5 mg/dl. Immediately after the first treatment session, the fibrinogen concentration was lowered to 100.7 ± 25.3 mg/dl (P < 0.001). The second and third sessions also showed highly significant reductions in plasma fibrinogen. No important side effects were seen. In conclusion, specific fibrinogen adsorption is a promising new treatment modality that should be tested in a prospective, randomized controlled trial in patients with sudden hearing loss. J. Clin. Apheresis 19:71,78, 2004. © 2004 Wiley-Liss, Inc. [source] Smoking and relation to other risk factors in postmenopausal women with coronary artery disease, with particular reference to whole blood viscosity and ,-cell functionJOURNAL OF INTERNAL MEDICINE, Issue 2 2003I. Os Abstract., Os I, Høieggen A, Larsen A, Sandset PM, Djurovic S, Berg K, Os A, Birkeland K, Westheim A (University of Oslo; Ulleval University Hospital; and Aker University Hospital, Oslo, Norway). Smoking and relation to other risk factors in postmenopausal women with coronary artery disease, with particular reference to whole blood viscosity and ,-cell function. J Intern Med 2003; 253: 232,239. Objectives., To investigate possible associations between smoking habits and other coronary risk factors in postmenopausal women with known coronary heart disease (CHD). Setting., The study was conducted at a university clinic. Subjects., A total of 118 postmenopausal women with CHD verified with angiography, consecutively recruited. Interventions., Conventional treatment for CHD. The women were randomized to hormone replacement therapy (HRT) with transdermal 17-, oestradiol and medroxyprogesterone acetate, or to a control group. Results., Smokers were younger (P = 0.005), had lower body mass index (P = 0.04) and lipoprotein Lp(a) levels (P = 0.02) compared with nonsmokers. Smokers had reduced ,-cell function (homeostasis model assessment, P = 0.006), whereas whole blood viscosity (WBV) was higher at all shear rates. WBV was not affected by HRT over a 12-month period. Oestrone levels were higher in smokers. Conclusions., Smoking adversely affects insulin secretion (,-cell function) and WBV in postmenopausal women with established CHD, which could be of importance as a mechanism for the increased risk of CHD in smokers. The importance of smoking as a risk factor, overrides the effect of Lp(a), which is lower in smokers compared with nonsmokers. [source] Favorable Impact of a Vegan Diet with Exercise on Hemorheology: Implications for Control of Diabetic NeuropathyJOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 2 2003MF McCarty A little-noticed clinical report indicates that a low-fat, whole-food vegan diet, coupled with daily walking exercise, leads to rapid remission of neuropathic pain in the majority of type 2 diabetics expressing this complication. Concurrent marked improvements in glycemic control presumably contribute to this benefit, but are unlikely to be solely responsible. Consideration should be given to the possibility that improved blood rheology , decreased blood viscosity and increased blood filterability , plays a prominent role in mediating this effect. There is considerable evidence that neural hypoxia, secondary to impaired endoneurial microcirculatory perfusion, is a crucial etiologic factor in diabetic neuropathy; the unfavorable impact of diabetes on hemorheology would be expected to exacerbate endoneurial ischemia. Conversely, measures which improve blood fluidity would likely have a beneficial impact on diabetic neuropathy. There is indeed evidence that vegan diets, as well as exercise training, tend to decrease the viscosity of both whole blood and plasma; reductions in hematocrit and in fibrinogen may contribute to this effect. The fact that vegan diets decrease the white cell count is suggestive of an improvement in blood filterability as well; filterability improves with exercise training owing to an increase in erythrocyte deformability. Whether these measures influence the activation of leukocytes in diabetics , an important determinant of blood filterability , remains to be determined. There are various reasons for suspecting that a vegan diet can reduce risk for other major complications of diabetes , retinopathy, nephropathy, and macrovascular disease , independent of its tendency to improve glycemic control in type 2 patients. The vegan diet/exercise strategy represents a safe, ,low-tech' approach to managing diabetes that deserves far greater attention from medical researchers and practitioners. [source] Neurologic Dysfunction in Hypothyroid, Hyperlipidemic Labrador RetrieversJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 6 2007Christina L. Vitale Background: Hypothyroidism has been associated with a variety of neurologic signs, but the mechanism for this association is not completely understood. Hypothyroidism also is associated with hyperlipidemia that predisposes to atherosclerosis, increased blood viscosity, and thromboembolic events. Objective: The objective is to characterize neurologic signs potentially associated with hyperlipidemia and atherosclerosis in canine hypothyroidism. Animals: This study used dogs referred to North Carolina State University Veterinary Teaching Hospital for evaluation of neurologic signs. Materials and Methods: A retrospective study was conducted in which medical records of dogs with neurologic signs and a diagnosis of hypothyroidism and hyperlipidemia were reviewed. Details of the history, presenting signs, results of routine blood tests, thyroid tests, cerebrospinal fluid (CSF) analysis and diagnostic imaging, and response to therapy were compiled. Results: Three Labrador Retrievers and one Labrador Retriever cross fit the inclusion criteria. All dogs were hypothyroid and severely hyperlipidemic. Neurologic signs included tetraparesis, central and peripheral vestibular signs, facial paralysis, and paraparesis. Two dogs had an acute history and rapid resolution of signs consistent with an infarct, the presence of which was confirmed in 1 of the dogs by magnetic resonance imaging. Two dogs had chronic histories of cranial neuropathies and paraparesis. One of these dogs had evidence of iliac thrombosis and atherosclerosis on ultrasound examination. All dogs improved with thyroid hormone supplementation. Clinical Relevance: Labrador Retrievers may be predisposed to the development of severe hyperlipidemia in association with hypothyroidism. One possible consequence of severe hyperlipidemia is the development of neurologic signs due to atherosclerosis and thromboembolic events. [source] Isoxsuprine hydrochloride in the horse: a reviewJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 2 2002R. S. ERKERT Isoxsuprine hydrochloride has been suggested for use in horses for treatment of navicular syndrome and laminitis. The drug has been shown to be a , -adrenoreceptor antagonist with , -adrenoreceptor agonistic properties, with both characteristics contributing to vasodilation and uterine relaxation. In addition, the drug is capable of decreasing blood viscosity and platelet aggregation. Studies have shown i.v. isoxsuprine to have a plasma half-life of <3 h with a large apparent volume of distribution. Cardiovascular effects resolve rapidly following i.v. administration, but are absent with oral dosing. Oral bioavailability is 2.2% with a high first pass effect. Isoxsuprine has an apparent affinity for melanin that may contribute to extended renal excretion. Clinical trials appear to support the use of isoxsuprine for treatment of navicular disease. However, poor bioavailability, lack of cardiovascular effects following oral administration, superficial support in clinical trials, and new evidence regarding the pathogenesis of navicular syndrome indicate that the use of isoxsuprine for treatment of navicular syndrome or laminitis is questionable at best. [source] Microvascular Rheology and HemodynamicsMICROCIRCULATION, Issue 1 2005HERBERT H. LIPOWSKY ABSTRACT The goal of elucidating the biophysical and physiological basis of pressure,flow relations in the microcirculation has been a recurring theme since the first observations of capillary blood flow in living tissues. At the birth of the Microcirculatory Society, seminal observations on the heterogeneous distribution of blood cells in the microvasculature and the rheological properties of blood in small bore tubes raised many questions on the viscous properties of blood flow in the microcirculation that captured the attention of the Society's membership. It is now recognized that blood viscosity in small bore tubes may fall dramatically as shear rates are increased, and increase dramatically with elevations in hematocrit. These relationships are strongly affected by blood cell deformability and concentration, red cell aggregation, and white cell interactions with the red cells and endothelium. Increasing strength of red cell aggregation may result in sequestration of clumps of red cells with either reductions or increases in microvascular hematocrit dependent upon network topography. During red cell aggregation, resistance to flow may thus decrease with hematocrit reduction or increase due to redistribution of red cells. Blood cell adhesion to the microvessel wall may initiate flow reductions, as, for example, in the case of red cell adhesion to the endothelium in sickle cell disease, or leukocyte adhesion in inflammation. The endothelial glycocalyx has been shown to result from a balance of the biosynthesis of new glycans, and the enzymatic or shear-dependent alterations in its composition. Flow-dependent reductions in the endothelial surface layer may thus affect the resistance to flow and/or the adhesion of red cells and/or leukocytes to the endothelium. Thus, future studies aimed at the molecular rheology of the endothelial surface layer may provide new insights into determinants of the resistance to flow. [source] Evaluation of Baccharis trimera and Davilla rugosa in tests for adaptogen activityPHYTOTHERAPY RESEARCH, Issue 6 2007Fúlvio Rieli Mendes Abstract Baccharis trimera (Asteraceae) and Davilla rugosa (Dilleniaceae) are used popularly as tonics, aphrodisiacs and for stomach ailments, among other uses. Hydroalcohol extracts of the aerial parts of both plants were investigated with regard to their chemical constitution and their pharmacological activity in tests that evaluate adaptogen activity. Alkaloids, flavonoids, saponins, polyphenols/tannins and coumarins were identified in both extracts, while lignans were found only in the extract of Davilla rugosa. This extract presented also a marked antioxidant activity and exerted a moderate antiulcer effect in rats submitted to cold immobilization stress. It did not, however, inhibit the increase in the levels of ACTH and corticosterone induced by stress. Moreover, the Davilla rugosa did not improve the physical performance of mice submitted to forced exercise and the learning time of old rats in the T-maze, neither did it reduce the blood viscosity of the old animals. Conversely, the Baccharis trimera extract only presented a moderate antioxidant activity, without any positive effect on the other tests. These results point to the absence of an adaptogen activity of Baccharis trimera, with some effects that could be related to such an activity as regards the Davilla rugosa. Copyright © 2007 John Wiley & Sons, Ltd. [source] Hemorheologic profile in systemic sclerosis: Role of NOS3 ,786T>C and 894G>T polymorphisms in modulating both the hemorheologic parameters and the susceptibility to the diseaseARTHRITIS & RHEUMATISM, Issue 7 2006Cinzia Fatini Objective Microvascular disorders are relevant in systemic sclerosis (SSc). Hyperviscosity, due to alterations of blood cells and plasma components, may play a role in the pathogenesis of microcirculatory disorders. An impaired availability of nitric oxide, related to polymorphisms in NOS3, the gene for endothelial cell nitric oxide synthase, might influence erythrocyte deformability. We undertook this study to investigate the hemorheologic profile in SSc and the role of NOS3 polymorphisms in modulating the hemorheologic status of SSc patients. Methods We studied 113 consecutive SSc patients (75 with limited cutaneous SSc [lcSSc] and 38 with diffuse cutaneous SSc [dcSSc]) and 113 healthy controls. The hemorheologic profile was obtained by assessing whole blood viscosity (WBV; at shear rates of 0.512 and 94.5 seconds,1), plasma viscosity (PLV; at a shear rate of 94.5 seconds,1), and erythrocyte deformability index (DI). We determined NOS3 polymorphisms by molecular analysis. Results A marked alteration of hemorheologic parameters was found both in patients with lcSSc and in those with dcSSc compared with controls (P < 0.0001). In multivariate analysis, rheologic variables were significantly associated with the disease (for WBV at a shear rate of 94.5 seconds,1, odds ratio [OR] 5.4, 95% confidence interval [95% CI] 1.4,19.9, P = 0.01; for PLV, OR 2.8, 95% CI 1.2,6.5, P = 0.01; for DI, OR 3.9, 95% CI 1.4,10.8, P = 0.007), and NOS3 ,786C and 894T alleles significantly affected the DI (for ,786C allele, OR 2.3, 95% CI 1.01,5.4, P = 0.04; for 894T allele, OR 2.2, 95% CI 1.01,4.8, P = 0.04). The simultaneous presence of the ,786C and 894T alleles represented a susceptibility factor for SSc (OR 2.8, 95% CI 1.4,5.7, P = 0.004). Conclusion Our findings document an altered rheologic profile in SSc and demonstrate a relationship between this alteration and NOS3 polymorphisms, thus shedding light on a potential novel mechanism influencing the microcirculation in this disease. [source] Development of Air Micro Bubbles in the Venous Outlet Line: An In Vitro Analysis of Various Air Traps Used for HemodialysisARTIFICIAL ORGANS, Issue 6 2007Christofer J. Stegmayr Abstract:, Venous air traps were tested in vitro with respect to presence of micro bubbles. Three types of venous air traps were measured (Bioline, Bioline GmbH, Luckenwalde, Germany; Gambro, Gambro AB, Lund, Sweden; Fresenius M.C., Fresenius Medical Care AG & Co. KGaA, Bad Homburg, Germany). Measurements (n = 10) were taken for each air trap, fluid flow (50,600 mL/min), and fluid level (high/low). A 1.5-MHz ultrasound probe was used with an analysis device. The probe was mounted on the outlet line downstream of the venous air trap. A semisynthetic fluid was used to resemble blood viscosity. Occurrences of micro bubbles, without inducing an alarm of the dialysis device, were detected in almost all measurements. The amount of bubbles increased with increasing flow. There were more bubbles with low fluid level compared with high level. The Bioline tubing released the least bubbles in high fluid level. At low level, the Gambro tubing showed the least bubbles at flows 50,400 mL/min, and the Fresenius M.C. tubing showed the least bubbles at flows 400,600 mL/min. High fluid level in the air trap reduced generation of micro bubbles compared to low level, as did lower fluid flow versus high flow. The design of the air trap was also of importance. [source] Physical Model-Based Indirect Measurements of Blood Pressure and Flow Using a Centrifugal PumpARTIFICIAL ORGANS, Issue 8 2000Tadashi Kitamura Abstract: This article describes a technique offering indirect measurements of pump pressure differential and flow with certain accuracy independent of changes in blood viscosity. This technique is based on noninvasive measurements of the motor current and rotation speed using the physical model equations of the centrifugal pump system. Blood viscosity included in the coefficients of the dynamic equations is first estimated, and then substitution of the estimated viscosity into the steady equations of the model provides pump flow and pressure differential. In vitro tests using a Capiox pump showed a sufficient linear correlation between actual values and their estimates for pressure differential and pump flow. An in vivo test using a 45 kg sheep showed that the proposed algorithm needs robustness for the convergence of estimates of viscosity. An overall evaluation, however, of the developed algorithm/model showed indications of success in terms of efficient computation and modeling. [source] Alimentary hyperlipemia of rabbits is affected by exposure to low-intensity pulsed magnetic fieldsBIOELECTROMAGNETICS, Issue 8 2007Erping Luo Abstract An experimental study was carried out in rabbits to investigate the effects of exposing rabbits to low-intensity pulsed magnetic fields (PMFs) on alimentary hyperlipemia. Thirty female white big ear rabbits were randomly divided into three groups. The normal group was fed with a standard chow diet and the other two groups (hyperlipid and magnetic) were fed with the chow diet supplemented with cholesterol, yolk powder and lard. The magnetic group was exposed to 15 Hz pulsed magnetic fields. After 8 weeks, levels of blood lipid and indices of hemorheology were examined. In addition, histomorphologic changes of hepatic and myocardial tissues were compared across the groups respectively. Compared with the hyperlipid group, hemorheology indices of the magnetic group reduced significantly from 12.80% to 38.05% (P,<,0.01) indicating lower blood viscosity. Similarly, compared with the hyperlipid group, the levels of total cholesterol and triglycerides in the magnetic group decreased 40.52% and 52.42% (P,<,0.01). On the contrary, high density lipoprotein (HDL) value obviously increased 66.67% (P,<,0.01). Furthermore, compared with the control group, the values of triglycerides and HDL of the magnetic group did not show statistical differences (P,>,0.05). The deposit of fatty material on the inner lining of thoracic aorta wall of the magnetic group was significantly lighter than that of the hyperlipid group. Numerous aggregation of lipoids emerged among myocardial myofibrils in the hyperlipid group, while no notable change was found in both the magnetic and control group. The results indicate that low-intensity PMFs could be helpful for the treatment of alimentary hyperlipemia. Bioelectromagnetics 28:608,614, 2007. © 2007 Wiley-Liss, Inc. [source] Commercial taxane formulations induce stomatocytosis and increase blood viscosityBRITISH JOURNAL OF PHARMACOLOGY, Issue 6 2001Michael Mark Taxanes are antineoplastic drugs which have cardiovascular side effects of unknown mechanism. We investigated their influence on blood viscosity and erythrocyte morphology. Whole blood was incubated in vitro with increasing concentrations of Taxol®, Taxotere®, paclitaxel (0 , 100 ,M) and the vehicles Cremophor-EL and Tween 80 (0 , 5% vol) for 1 h at 37°C. Plasma and whole blood viscosity (Haematocrit 45%) were measured and erythrocyte morphology was assessed on glutaraldehyde-fixed cells. The same investigations were performed in seven patients before and after a Taxol®-infusion. Taxol® and Taxotere® induced a dose- and time-dependent stomatocytic shape transformation of erythrocytes. Paclitaxel alone had no effect, but the vehicles cremophor-EL and Tween 80, used in Taxol® and Taxotere®, respectively, induced a comparable degree of stomatocytosis. This suggests a preferential intercalation of these substances into the inner hemileaflet of the membrane lipid bilayer. Associated with this shape change a dose-dependent increase in plasma and whole blood viscosity was observed. Neither shape nor viscosity changes were reversible upon removal of the agents. After the infusion of 130 , 300 mg Taxol® in patients a slight shift towards stomatocytosis and an increase in whole blood viscosity at high shear rate from 5.09±0.30 to 5.44±0.38 mPa.s (P<0.05) were confirmed. Commercial taxane drug formulations induce stomatocytosis and increase blood viscosity, which is due to their formulation vehicles. These findings may contribute to the understanding of the cardiovascular side effects of these drugs. British Journal of Pharmacology (2001) 134, 1207,1214; doi:10.1038/sj.bjp.0704387 [source] | |||||||||||||||||||||||||