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INTRODUCTION: Essential thrombocythemia (ET) is an entity of classic Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs), characterized by thrombocytosis with megakaryocytic hyperplasia where in the thrombocytes are increased with abnormal function. Thrombotic events are seen frequently and represent the main cause of morbidity and mortality in patients with MPNs, mainly polycythemia vera and ET. This study has aimed to research the effects of clonally increased thrombocytes on plasma viscosity (PV) levels among patients with ET and the relationship between PV and thromboembolism history, according to the hypotheses about the effects of PV in thromboembolic events among patients with ET. METHODS: A total of 55 patients were enrolled in the study group, 18 of who had been newly diagnosed with ET according to 2016 World Health Organization criteria and had not previously been treated. 37 of them had already been diagnosed with ET and had been treated. There were 47 healthy volunteers in the control group. 5 cc blood samples were taken from the patients into tubes including an anticoagulant to measure their PV levels. RESULTS: PV of the control group was found to be lower than in the study group and both each patient groups (p

Background Plasma viscosity is an important biomarker both in diagnostics and treatment monitoring of plasma cell dyscrasias and other disorders with hyperviscosity syndrome as a clinical manifestation. Here, we investigate the performance of a new microfluidic-based viscometer for clinical use, establish a new reference range to be used with this instrument and determine the importance of sampling temperature. Methods The microVisc™ viscometer was evaluated for within-run and between-run imprecision and bias using standardized reference material (Paragon controls) and Seronorm™ control material. The reference range was established for the adult population using EDTA-plasma from 120 healthy blood donors. Sampling temperature was investigated by drawing and transporting blood at room temperature and 37°C and comparing the viscosity between the two sampling methods. Results The microfluidic-based viscometer performed well, and imprecision was comparable to ReoRox® G2 free oscillation rheometer. A new reference range for the adult Danish population was established as 1.2–1.5 mPa s at 37°C. Furthermore, sampling temperature at room temperature and 37°C was investigated, and there was no difference in results obtained. Conclusions MicroVisc™ is suitable for measuring plasma viscosity in a clinical setting and results can be evaluated using the established reference range. Blood sampling for viscosity analysis can be performed as a standard procedure at room temperature.

As the underlying mechanisms of the adverse effects of cold spells on cardiac events are not well understood, we explored the effects of cold spells on plasma viscosity, a blood parameter linked to cardiovascular disease. This cross-sectional study involved 3622 participants from the KORA S1 Study (1984-1985), performed in Augsburg, Germany. Exposure data was obtained from the Bavarian State Office for the Environment. Cold spells were defined as two or more consecutive days with daily mean temperatures below the 3rd, 5th, or 10th percentile of the distribution. The effects of cold spells on plasma viscosity were explored by generalized additive models with distributed lag nonlinear models (DLNM). We estimated cumulative effects at lags 0-1, 0-6, 0-13, 0-20, and 0-27 days separately. Cold spells (mean temperature

Objective The aim of this study was to analyse the effects of dance movement therapy exercises (DMT) on the rheological properties of blood in elderly women. Methods The study encompassed group of women (mean aged: 67 years), who were subjected to three-month dance movement therapy programme (n = 20). Blood samples from all the women were examined for their haematological, rheological, and biochemical parameters both prior to the study and three months thereafter. Results DMT did not cause statistically significant differences in the number of erythrocytes, thrombocytes, leukocytes and the haematocrit value. DMT affected the rheological parameters of the blood in elderly women, improving the erythrocyte deformability at the lowest shear stress value and reducing the half-time of the total aggregation. Plasma viscosity and concentration of fibrinogen did not change after dance therapy. Conclusions DMT modulate rheological properties of blood of older women. The results of this study suggest that physical exercise program for older women can prevent unfavorable age-related changes. Some indicators such as the haematological parameters, plasma viscosity and fibrinogen level were not affected by DMT in older women, suggesting the maintenance of homeostasis.

In this case report, we examine the behavior of plasma viscosity, explored at high and low shear rates, and erythrocyte aggregation in two patients with congenital afibrinogenemia, a clinical disorder firstly described in 1920 and that has an estimated incidence of 1 : 1-200 0000. The two hemorheological parameters examined by us showed a marked decrease in both patients, in one of whom erythrocyte aggregation was even undetectable. Keeping in mind that spontaneous thrombosis (venous and arterial) has been often described in congenital afibrinogenemia, it can be hypothesized that the decrease in plasma viscosity and erythrocyte aggregation might cause a reduction of the endothelial synthesis and release of nitric oxide through the fall of the wall shear stress.

The dromedary camel and the oryx antelope are exposed to excessive heat and solar radiation in their desert habitat. Desertification of areas with by now little rainfall may occur eventually. Well-adapted large animal species show us what is needed to survive in scorching regions.Four scimitar-horned oryx antelopes (Oryx dammah), 10 camels (Camelus dromedarius), nine South African Merino sheep, and 17 Nguni cows were tested for RBC aggregation, RBC elongation, and plasma viscosity. The temperature dependency of blood viscosity was tested in 10 camels and compared to human reference values.Unlike sheep, Nguni cow, and dromedary camel, oryx RBCs aggregate in native plasma (M0:5.2 (3.3/6.7); M1:18.1 (16.7/27.9); Myrenne MA1). Elongation indices of oryx RBCs were intermediate to low (EImax: 22.6 (19.2/25.3); SS1/2 3.67 (2.52/4.95); Rheodyn SSD). Camel RBCs did not display the typical SS/EI curve by rotational ektacytometry. In-vitro blood viscosity (Physica MCR302) was lower in camels than in human blood at equal hematocrit. A decrease of temperature had only little effect on camel blood. At 10 s−1, blood viscosity in camel increased from 2.18mPa*s (2.01/2.37) at 42◦C to 4.39mPa*s (4.22/4.51) at 12◦C. In human blood, viscosity ranged from 8.21mPa*s (6.95/8.25) at 37◦C to 15.52mPa*s (14.25/16.03) at 12◦C. At 1000 s−1, blood viscosity in camel ranged from 2.00mPa*s (1.95/2.04) at 42◦C to 3.98mPa*s (3.88/4.08) at 12◦C. In human blood, viscosity ranged from 5.35mPa*s (4.96/5.87) at 37◦C to 11.24mPa*s (10.06/11.17) at 12◦C.Desert ungulates may need RBC membranes, which are fortified to withstand changes in osmolality during dehydration-rehydration cycles. This reduces RBC deformability. Dromedary camel blood does not undergo stark changes in viscosity with changes in temperature. Therefore, blood fluidity could be rather maintained during the day and night cycle. This should reduce the need of the vascularity to rhythmically adapt to changing shear forces when camels experience heterothermy.

The hemorheological profile in multiple myeloma (MM) has been extensively studied. Our investigation regarded the behavior of whole-blood viscosity, plasma viscosity and erythrocyte deformability in MM. We enrolled 24 MM patients; 13 of them had been recently diagnosed and were at the initial stage of therapy, 6 were on consolidation/conservation therapy and 5 had achieved a complete remission. On fasting venous blood we evaluated whole-blood and plasma viscosity at high and low shear rates, haematocrit, the ratios between whole-blood viscosity (at high and low shear rate) and haematocrit×100, the ratio between plasma viscosity at low and high shear rate and the erythrocyte deformability examined by using laser diffractometry and expressed as elongation index. A significant increase in plasma viscosity at low shear rate and a marked decrease in haematocrit were observed in MM patients compared with normal controls. Also the ratio between the high shear rate whole-blood viscosity and haematocrit ×100 and the ratio between the low and high shear rate plasma viscosity were significantly increased in MM patients. A significant decrease in erythrocyte deformability, especially at low shear stresses, was found. We discuss some hypotheses that might explain the behavior of red blood cell deformability in MM, considering that its impairment, in addition to the increase of plasma viscosity, can alter the microcirculatory flow in these patients.

Background Cryotherapy is a physiotherapy method used to treat back pain in older persons. Objective This study aims to evaluate the changes in the rheological parameters of blood in older women with spondyloarthrosis, who underwent whole-body cryotherapy. Methods The experimental group comprised 69 older women with lumbar spondyloarthrosis, aged between 65 and 70 years. Due to the methodology of the procedure, the experimental group was randomly divided into three groups. Each group underwent two weeks of different types of physiotherapy: only whole-body cryotherapy (22 women); only kinesitherapy (23 women); and both cryotherapy and kinesitherapy (24 women). The control group comprised 25 women who did not undergo any form of therapy. The evaluation of the rheological properties of the blood encompassed measurements of the plasma viscosity, the erythrocyte elongation and aggregation indices, and the level of fibrinogen. Results The conducted rheological tests revealed a significant decrease in the erythrocyte elasticity and aggregation indices only in the group of women who had undergone both whole-body cryotherapy and kinesitherapy. Conclusions Applying whole-body cryotherapy to older women with spondyloarthrosis decreases the elasticity of erythrocytes and, despite favourable changes in the aggregation parameters, problems with perfusion may still appear. For this reason, the benefit of using whole-body cryotherapy in these persons is debatable.

WOS: 000400599300001, PubMed ID: 27814281, AIM: To evaluate hemorheological parameters in patients with fibromyalgia syndrome (FMS) in order to elucidate the etiology of the disease. METHODS: Twenty-three adult FMS patients and 20 healthy controls were enrolled in the study. Diabetics, hypertensives and those with any rheumatological disorder or use drugs or smoking cigarette were excluded from the study. Following parameters were analyzed in each subject; erythrocyte deformability, erythrocyte aggregation, plasma viscosity, complete blood count, fasting blood glucose, fibrinogen, albumin, globulin and lipid profile. RESULTS: Erythrocyte elongation indices indicating deformability of erythrocytes were higher in FMS patients (0.564 +/- 0.002 at 16.87mPa and 0.605 +/- 0.002 at 30mPa shear rate) than controls (0.558 +/- 0.001 at 16.87mPa and 0.600 +/- 0.003 at 30mPa shear rate). Erythrocyte aggregation speed was higher in FMS patients (2.1 +/- 0.1 s) than controls (2.3 +/- 0.2 s). Erythrocyte aggregation index was also higher in FMS patients (65.5 +/- 1.3) than controls (62.9 +/- 1.5). Erythrocyte aggregation amplitude and plasma viscosity values were similar in both groups (both p > 0.05). Among the complete blood count and biochemical parameters, only albumin levels were lower in the FM patients than controls (p < 0.05). CONCLUSION: Our results indicate higher erythrocyte deformability and quicker erythrocyte aggregation in FM patients., Hacettepe University Scientific Research Administration, This study was supported by Hacettepe University Scientific Research Administration.

Background The diagnosis of prosthetic joint infection (PJI) is challenging because no single test has consistently demonstrated an adequate discriminative potential. The combination of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) with adequate thresholds is well established. This study sought to investigate the role of plasma viscosity (PV) in the diagnosis of PJI following painful total knee arthroplasty. Methods The medical notes, and hematological and microbiology results of 310 patients who underwent revision for a painful total knee arthroplasty were evaluated. Infection was confirmed using Musculoskeletal Infection Society criteria in 102 patients (32.9%), whereas 208 patients (67.1%) were classified as noninfected. Serum investigations including ESR, CRP, and PV were analyzed using receiver observer curves and optimal cutoff points identified. Results There was a strong correlation between PV and both ESR and CRP. The area under curve was 0.814 for PV and 0.812 for ESR. Statistical analysis showed noninferiority of PV as compared to ESR in diagnosing PJI. A PV value of ≥ 1.81 mPa.s. had the best efficiency of 82.1%. Combining a CRP ≥ 13.5 mg/L with a PV ≥ 1.81 mPa.s. in a serial test approach yielded the highest specificity of 97.9% and positive likelihood ratio of 22.8. Sensitivity was 47.9% and a negative likelihood ratio of 0.53. Conclusion PV is noninferior to ESR in diagnosing PJI. Its use is justified in clinical practice. It is cheaper, quicker, more efficient, and not influenced by hematocrit levels or medication. In this cohort, a PV value ≥ 1.81 mPa.s. would be an adequate cutoff to diagnose PJI in combination with CRP ≥ 13.5 mg/L.

Background Atherosclerosis is a degenerative disease of the arterial wall. It results in the formation of progressively growing plaque lesions that can harden and narrow their host arteries. Current computational models of the inflammatory process that govern atherosclerosis growth are reliant on a number of parameters that can freely vary and whose precise values are not well known. Methods To identify the significance of variation in such parameters, a parametric sensitivity study had been conducted on the blood density, blood viscosity, plasma viscosity and bulk flow low density lipoprotein (LDL) concentration. Using computational modeling, the significance of variation in these parameters was assessed on the transport of LDL. The simulation was performed via the 2k factorial experimental design, which was conducted to identify the significance of the select parameters on the intima LDL concentration and endothelial LDL coverage area. Results Results identified the blood viscosity and bulk flow LDL concentration are the dominant parameters for the atherosclerotic lesion growth. The coverage of LDL on the arterial wall surface was strongly dependent on the blood viscosity. The significance of these findings was discussed. Conclusion This statistical study identifies two dominating blood factors, LDL concentration and blood viscosity, and how they influence atherosclerosis which will serves as a guideline for further investigation on the atherosclerosis topic.

The aim of the study is to test the influence of in vivo magnetostimulation on the rheological properties of blood in neurological patients. Blood circulation in the body depends both on the mechanical properties of the circulatory system and on the physical and physicochemical properties of blood. The main factors influencing the rheological properties of blood are as follows: hematocrit, plasma viscosity, whole-blood viscosity, red cells aggregability, deformability, and the ability of red cells to orient in the flow. The blood samples were collected from neurological patients with pain. Blood samples were collected twice from each patient, that is, before the magnetostimulation and immediately after the therapy. For each blood sample, the hematocrit value was measured using the standard method. Plasma viscosity and whole-blood viscosity were measured by means of a rotary-oscillating rheometer Contraves LS40. Magnetic field was generated by the instrument Viofor JPS® and the magnetostimulation treatments were performed using M1P2 and M1P3 programs. The analysis of the results included estimation of the hematocrit value (Hct), plasma viscosity (ηp), whole-blood viscosity and rheological parameters of Quemada's model: k0, k∞, γ'c. Plasma viscosity values were obtained from the shear rate dependence of shear stress using the linear regression method. The results obtained in the study suggest that the blood rheological properties change in accord with applied magnetostimulation program.

Background Preclinical studies report that higher plasma viscosity improves microcirculatory flow after haemorrhagic shock and resuscitation, but no clinical study has tested this hypothesis. Objective We investigated the relationship between plasma viscosity and sublingual microcirculatory flow in patients during resuscitation for traumatic haemorrhagic shock (THS). Methods Sublingual video-microscopy was performed for 20 trauma patients with THS as soon as feasible in hospital, and then at 24 h and 48 h. Values were obtained for total vessel density, perfused vessel density, proportion of perfused vessels, microcirculatory flow index (MFI), microcirculatory heterogeneity index (MHI), and Point of Care Microcirculation (POEM) scores. Plasma viscosity was measured using a Wells-Brookfield cone and plate micro-viscometer. Logistic regression analyses examined relationships between microcirculatory parameters and plasma viscosity, adjusting for covariates (systolic blood pressure, heart rate, haematocrit, rate and volume of fluids, and rate of noradrenaline). Results Higher plasma viscosity was not associated with improved microcirculatory parameters. Instead, there were weakly significant associations between higher plasma viscosity and lower (poorer) MFI (p = 0.040), higher (worse) MHI (p = 0.033), and lower (worse) POEM scores (p = 0.039). Conclusions The current study did not confirm the hypothesis that higher plasma viscosity improves microcirculatory flow dynamics in patients with THS. Further clinical investigations are warranted to determine whether viscosity is a physical parameter of importance during resuscitation of these patients.

The aim of this study was the evaluation of the erythrocyte deformability in multiple myeloma (MM). We enrolled 29 MM patients and we evaluated, on fasting venous blood, the erythrocyte deformability, expressed as elongation index, and examined using the diffractometric method. By comparing normal controls and MM patients, a significant decrease in erythrocyte deformability, especially at low shear stresses, was found. In this research paper we evaluated all the hypothesis for a possible explanation of the behaviour of red blood cell deformability in MM, even considering how the alteration of erythrocyte deformability worsens the microcirculatory flow in these patients in association with the marked increase in plasma viscosity.

Rheological blood parameters of neonates are different form those of adults. Many authors have studied changes in blood rheology in neonates in different clinical disorders. To-date, no one set the normal values for blood rheological parameters in healthy neonates. The aim of this study is to set the norm for rheological blood parameters in healthy newborns and to describe the changes in those parameters in common clinical disorders that affect the newborns. We recruited all the neonates born to mothers experiencing un eventful pregnancies, blood was taken from the umbilical cord right after the delivery. In this time period we recruited 4985 neonate. From this huge database we were able to set the standards for blood rheology in neonates, namely plasma viscosity of 1.06±0.072 mPa, erythrocyte aggregation at stasis of 2.41±2.74 s-1 and erythrocyte aggregation under low shear forces of 8.51±6.38 s-1. These values changed significantly in some diseased neonates. This is the largest study investigating normal rheological parameters and deviations from the norm in common clinical disorders occurring in this early stage of life.

Peripheral artery occlusive disease (PAOD) is associated with increased cardiovascular risk (CVR). Recently it has been reported that also the increased stiffness of lower limb arteries is associated with increased CVR. In particular, subjects with poorly compressible arteries (PCA) appear to have a CVR even higher than that of subjects with PAOD. Limited data are available on the role of hemorheological factors in determining increase in arterial stiffness. Our study aimed to investigate possible association between blood and plasma viscosity and elevated ankle brachial index (ABI).Subjects were free-living participants to a cardiovascular disease screening campaign. Sixty-two subjects with ABI ranging 1.3-1.4, and 20 with ABI1.4 were matched with 124 and 40 control subjects, respectively. Cardiovascular disease risk factors (blood pressure, blood lipids, glucose, cigarette smoking, obesity) were evaluated by routine methods. Blood and plasma viscosities were measured by a cone-plate viscometer. Ankle-brachial index was computed as measure of arterial stiffness.Compared with controls, who were carefully matched for age, sex and all cardiovascular risk factors, subjects with elevated ABI values had increased levels of plasma viscosity (1.42 ± 0.11 vs. 1.35 ± 0.10 cP, p 0.001, for subjects with ABI ranging 1.3-1.4, and 1.41 ± 0.10 vs. 1.33 ± 0.10 cP, p 0.01, for subjects with ABI1.4). No difference in blood viscosity was observed.The present investigation provides evidence that plasma viscosity is increased in subjects with elevated ABI values, independently of other cardiovascular risk factors. This finding contributes to explain the high CVR of patients with PCA.

International audience; The aim of this study was to test the accuracy of viscosimetric method to estimate the red blood cell (RBC) deformability properties. Thirty-three subjects were enrolled in this study: 6 healthy subjects (AA), 11 patients with sickle cell-hemoglobin C disease (SC) and 16 patients with sickle cell anemia (SS). Two methods were used to assess RBC deformability: 1) indirect viscosimetric method and 2) ektacytometry. The indirect viscosimetric method was based on the Dintenfass equation where blood viscosity, plasma viscosity and hematocrit are measured and used to calculate an index of RBC rigidity (Tk index). The RBC deformability/rigidity of the three groups was compared using the two methods. Tk index was not different between SS and SC patients and the two groups had higher values than AA group. When ektacytometry was used, RBC deformability was lower in SS and SC groups compared to the AA group and SS and SC patients were different. Although the two measures of RBC deformability were correlated, the association was not very high. Bland and Altman analysis demonstrated a 3.25 bias suggesting a slight difference between the two methods. In addition, the limit of agreement represented 28% (>15%) of the mean values of RBC deformability, showing no interchangeability between the two methods. In conclusion, measuring RBC deformability by indirect viscosimetry is less accurate than by ektacytometry, which is considered the gold standard.

There is scarcity of information about the hemorheological pattern in subjects with Monoclonal Gammopathy of Undetermined Significance (MGUS). This preliminary research is focused on the behaviour of whole-blood and plasma viscosity, haematocrit and erythrocyte deformability in the above clinical condition. We enrolled 21 MGUS subjects (10 women and 11 men; mean age 66.4 ± 11.6 years). In fasting venous blood we examined whole-blood and plasma viscosity at high and low shear rates, haematocrit, the ratios between whole-blood viscosity (at high and low shear rate) and haematocrit × 100, the ratio between plasma viscosity at low and high shear rate, and the erythrocyte deformability expressed as elongation index. By comparing normal controls to MGUS subjects a significant increase in whole-blood viscosity at high shear rate and in plasma viscosity at low shear rate were observed. In MGUS subjects the ratios between the high and low shear rate blood viscosity and haematocrit × 100, as well as the ratio between the low and high shear rate plasma viscosity were significantly higher. In MGUS subjects a marked decrease in erythrocyte deformability was also observed. The alteration of the hemorheological profile found in these subjects might be involved in the pathogenesis of thromboembolic events, which occur with a high frequency in MGUS.

Objective The aim of this study was to analyze the effects of dance therapy on selected hematological and rheological indicators in older women. Methods The study included 30 women (aged 71.8±7.4), and the control group comprised of 10 women of corresponding age. Women from the experimental group were subjected to a five-month dance therapy program (three 45-minute sessions per week); women from the control group were not involved in any regular physical activity. Blood samples from all the women were examined for hematological, rheological, and biochemical parameters prior to the study and five months thereafter. Results The dance therapy program was reflected by a significant improvement of erythrocyte count and hematocrit. Furthermore, the dance therapy resulted in a significant increase in the plasma viscosity, while no significant changes in glucose and fibrinogen levels were noted. Conclusions Dance therapy modulates selected hematological parameters of older women; it leads to increase in erythrocyte count and hematocrit level. Dance therapy is reflected by higher plasma viscosity. Concentrations of fibrinogen and glucose are not affected by the dance therapy in older women, suggesting maintenance of homeostasis. Those findings advocate implementation of dance therapy programs in older women.

Elevated plasma viscosity (PV) is observed in patients with vascular risk factors, such as diabetes mellitus or arterial hypertension. In this study we investigated the association of plasma viscosity and the different clinical and radiological entities of cerebral ischemia.PV of 465 consecutively admitted patients with clinical symptoms of acute cerebral ischemia without radiological signs of bleeding was measured. Data is expressed as median [range] unless stated otherwise. p0.05 was considered statistically significant.Patients with acute cerebral ischemia (TIA or Stroke) showed increased PV (TIA 1.27mPas [1.07-1.53], stroke 1.27mPas [1.07-1.56]) compared to patients without cerebral ischemia (Mimics) (1.23mPas [1.06-1.42]). The group with radiologically proven small vessel disease (SVD) had a significantly higher mean values of PV (1.29mPas [1.06-1.54]) compared to those with signs of large vessel disease or cardioembolic events (1.22mPas [1.07-1.56], p0.001). Patients with chronic heart failure (p=0.007), arterial hypertension (p0.001) and diabetes mellitus (p=0.002) had higher PV compared to patients without these cardiovascular risk factors. Hyperlipidemia or nicotine abuse showed no relation to PV.Elevated PV is not only associated TIA and Stroke but is also found in patients with radiological signs of cerebral SVD. High levels of PV could be an underestimated risk for TIA and Stroke and participate in the complex pathophysiology of SVD. Prospective observational and interventional studies are warranted for further evaluation of PV in neurological ischemic diseases.

Plasma viscosity (PV) and erythrocyte sedimentation rate (ESR) are tests which can be used as inflammation and tissue injury markers [2, 11]. ESR usage is more extended than PV in clinical laboratories. However ESR may be haematocrit (Ht) dependent and is related with red blood cell (RBC) rheological properties [1], whereas RBC are not involved in PV. We aimed to evaluate retrospectively the impact of Ht on ESR as an inflammatory marker and compare the results with those of PV in 333 outand in-patients at our hospital. Our study is a human non-interventional retrospective review and written consent is not required for human non-interventional studies. We evaluated both markers in two patient groups of i.e., the first one did not present other inflammatory components measured as C-reactive protein (CRP) below 10 mg/L and fibrinogen below 450 mg/dL (n= 211). The second one presented CRP over 10 mg/L and/or fibrinogen values higher than 450 mg/dL (n= 122). PV and ESR were determined in a capillary plasma viscosimeter (Fresenius GmbH, Germany) at 37◦C and using a Ves matic 30 Plus Analyzer (Diesse Diagnostica Senese, Siena, Italy), respectively. CRP was determined by immunoturbidity in an AU5430 autoanalyzer (Beckman Coulter, Lexington, KY, USA) and fibrinogen analysis was performed in an ACL-TOP 700 autoanalyzer (Instrumentation Laboratory, Bedford, MA, USA).

Plasma or serum hyperviscosity in plasma cell dyscrasias (PCD) has been described as a risk factor for circulatory disturbances. Whole blood viscosity (WBV) would theoretically be a better biomarker but has not been studied in PCD.Plasma viscosity (PV) and WBV were measured in 89 subjects with PCD and in 60 healthy blood donors by free oscillation rheometry. A complete blood count was obtained using an automated hematology analyzer. Plasma proteins were quantitated by immunoturbidimetry.The reference intervals for menwomen were 1.16-1.361.16-1.38 mPa for PV, and 4.9-6.34.4-6.2 mPa for WBV, respectively. Of the PCD patients, 71% had PV above the reference limit and 40% were above the WBV limit. Multivariate analysis showed that WBV was independently related to hematocrit, PV, concentration of the monoclonal protein (M-protein), plasma fibrinogen concentration and albumin concentration. This model accounted for 76% of the variance in WBV. When the same model was applied to PV, only the concentration of the M-protein was significantly related and the model accounted only for 20% of the variance in PV.PV cannot be used as a surrogate marker for WBV in PCD patients. Whole blood viscosity should replace plasma viscosity in patients with PCD.

Unhealthy dietary fats are associated with faster kidney function decline. The cell membrane composition of phospholipid fatty acids (FAs) is a determinant of membrane fluidity and rheological properties. These properties, which have been linked to kidney damage, are thought to be reflected by the lipophilic index (LI). We prospectively investigated the associations of LI with kidney function and its decline.Observational study from the Prospective Investigation of Vasculature in Uppsala Seniors including 975 men and women with plasma phospholipid FAs composition and cystatin-C estimate glomerular filtration rate (eGFR). Of these, 780 attended re-examination after 5 years, and eGFR changes were assessed. Participants with a 5-year eGFR reduction ≥30% were considered chronic kidney disease (CKD) progressors (n = 198). LI was calculated as the sum of the products of the FA proportions with the respective FAs melting points. Blood rheology/viscosity measurements were performed in a random subsample of 559 subjects at baseline. Increased LI showed a statistically significant but overall weak association with blood, plasma viscosity (both Spearman rho = 0.16, p 0.01), and erythrocyte deformability (rho = -0.09, p 0.05). In cross-sectional analyses, LI associated with lower eGFR (regression coefficient 3.00 ml/min/1.73 mA high LI was associated with lower kidney function, kidney function decline, and CKD progression.

We previously reported that low intensity endurance training in sedentary patients suffering from the metabolic syndrome improves blood rheology, mostly due to a decrease in plasma viscosity correlated with an increase in cardiorespiratory fitness. We investigated whether these findings can be extended to type-2 diabetics. 22 diabetics (11 women and 10 men, age: 52.00 ± 2.9 yr, BMI: 32.47 ± 1.17 kg/m 2 ) were tested before and after 2 months. Eight of them were trained (2 to 3 × 45 min/wk) at the power intensity where lipid oxidation reaches a maximum (LIPOX max) and thirteen served as controls. Over this period the only significant hemorheological effect of training was a decrease in RBC aggregation "M" (−1.25 ± 0.357 p = 0.01) in the trained group. Subjects who lost weight exhibited a decrease in plasma viscosity (from 1.46 ± 0.013 to 1.38 ± 0.02 p < 0.01). Changes in waist circumference are associated with changes in hematocrit (r = −0.952 p = 0.01); plasma viscosity (r = −0.91; p = 0.03); RBC aggregation ("M" r = 0.940; p = 0.02). Subjects can also be divided into those who improved their aerobic capacity VO2max and those whose VO2max decreased or remained unchanged. An increase in VO2max is associated with a decrease in whole blood viscosity (r = −0.79 p = 0.06) explained by an improvement in RBC rigidity "Tk" (r = −0.963 p = 0.002). This study suggests that in Type 2 diabetic patients: (a) viscosity factors might be less responsive to training than in non diabetic individuals; (b) visceral fat loss is the main determinant of changes in hematocrit, plasma viscosity and RBC aggregation; (c) improvements in aerobic capacity improves blood viscosity via an increase in RBC deformability.

Background: Subclinical hypothyroidism (SH) is defined as elevated serum thyroid-stimulating hormone (TSH) concentration associated with normal serum-free thyroxine levels. Effects of hypothyroidism on hemorheology had widely attracted the attention of researchers during the last decade. Objective: The purpose of this study is to determine alterations in hemorheological parameters and carotid intima-media thickness (CIMT) in children with SH. Methods: Fifty-three SH children and 31 healthy controls were enrolled. Erythrocyte deformability and aggregation were determined by an ektacytometer and plasma viscosity (PV) by a cone-plate rotational viscometer. CIMT was evaluated sonographically. Results: Erythrocyte deformability of the SH group measured at 0.53 and 1.69-30 Pa was lower than that of the control group. The erythrocyte aggregation index, aggregation half time and PV were not different between the groups. However, the aggregation amplitude and mean corpuscular hemoglobin concentration were significantly higher in SH compared to the control group. There was a negative correlation between TSH and deformability values measured at 5.33-30.0 Pa. CIMT in patients with SH was significantly higher than in the control group (p = 0.001; SH = 0.48 ± 0.04 mm, control group = 0.43 ± 0.03 mm). Conclusion: Impaired hemorheology and increased CIMT are well-known risk factors for developing cardiovascular pathologies. The results of the current study suggest the treatment of children with SH in order to avoid early circulatory problems. © 2016 S. Karger AG, Basel.

OBJECTIVE Structure and mechanical properties of red blood cells are markedly influenced by pathophysiology of many diseases which in turn potentially impair microcirculatory blood flow. The physiological association between blood rheological parameters and red blood cell indices was investigated in otherwise healthy unselected mid-age women prior to elective gynaecological surgery. METHODS Red Blood Cell-deformability (RBC 1.2, 3.0; 6.0, 12.0; 30.0, 60.0) during exposure to low (RBC 1.2, 3.0), moderate (RBC 16.0, 12.0) and high shear forces (RBC 30.0, 60.0; Rheodyn; Myrenne), -aggregation (MA1; Myrenne) during low shear (E1; 4-1 S) and in stasis (E0) and plasma viscosity (Pv; KSV 1; Fresenius) were correlated with red blood cell indices (RBC-I: MCV, MCH and MCHC) and subjects' characteristics in 286 healthy women the day before undergoing gynaecologic standard surgery. Women with known pregnancy, malign-, infective-, chronic-disease or extreme BMI ( 40 Kg/m2) were excluded from this trial. RESULTS From June 2014 to December 2014 a total of 286 healthy women (age: 46.5±17.6 y; BMI: 25.5±5.2 kg/m2) were eligible for inclusion into this prospective evaluation. Pv (mean±SD: 1.17±0.12 mPa s) and RBC aggregation (E0:12.6±6.3; E1:17.9±7.3) were not significantly correlated with RBC-I but with age and BMI. In contrast, RBC-deformability correlated significantly with MCV and MCH but significantly inversely correlated with MCHC. Deformability significantly increased with age but was unaffected by BMI of women. The correlation between RBC-I and RBC deformability was most remarkable during moderate shear force exposure. Neither haemoglobin nor haematocrit were correlated with RBC deformability or RBC-I. CONCLUSIONS Cell volume and haemoglobin content had a strong impact on deformability in apparently healthy mid age women, whereas low MCHC and large MCV were associated with an increase in deformability while high MCHC and small MCV correlated with increased rigidity of RBC. BMI had no impact on deformability while age was associated with an increase in all determinants of blood viscosity. RBC aggregability was not affected by MCV, MCHC or MCH in mid-age women.

Background: Subclinical hypothyroidism (SH) is defined as elevated serum thyroid-stimulating hormone (TSH) concentration associated with normal serum-free thyroxine levels. Effects of hypothyroidism on hemorheology had widely attracted the attention of researchers during the last decade. Objective: The purpose of this study is to determine alterations in hemorheological parameters and carotid intima-media thickness (CIMT) in children with SH. Methods: Fifty-three SH children and 31 healthy controls were enrolled. Erythrocyte deformability and aggregation were determined by an ektacytometer and plasma viscosity (PV) by a cone-plate rotational viscometer. CIMT was evaluated sonographically. Results: Erythrocyte deformability of the SH group measured at 0.53 and 1.69-30 Pa was lower than that of the control group. The erythrocyte aggregation index, aggregation half time and PV were not different between the groups. However, the aggregation amplitude and mean corpuscular hemoglobin concentration were significantly higher in SH compared to the control group. There was a negative correlation between TSH and deformability values measured at 5.33-30.0 Pa. CIMT in patients with SH was significantly higher than in the control group (p = 0.001; SH = 0.48 ± 0.04 mm, control group = 0.43 ± 0.03 mm). Conclusion: Impaired hemorheology and increased CIMT are well-known risk factors for developing cardiovascular pathologies. The results of the current study suggest the treatment of children with SH in order to avoid early circulatory problems.

Background: Hemorheological properties are important determinants of tissue oxygenation. Although hemorheological alterations in various lung diseases have been well-defined, no information is available about the effects of idiopathic interstitial pneumonia (IIP) on hemorheological parameters. Objectives: The aim of this study was to investigate hemorheological parameters (erythrocyte deformability, aggregation, and plasma viscosity-PV) and associated oxidative stress indices in patients with IIP. Methods: The study enrolled 31 patients (9 Idiopathic pulmonary fibrosis (IPF), 10 non-specific Interstitial Pneumonia (NSIP), 12 Cryptogenic Organising Pneumonia (COP) and 33 healthy controls. Erythrocyte deformability and aggregation were measured by an ektacytometer. PV was determined by a cone-plate rotational viscometer and oxidative stress via a commercial kit. Results: Erythrocyte aggregation, total oxidant status (TOS) and oxidative stress index (OSI) of IIP patients were higher than controls whereas erythrocyte deformability, PV and total antioxidant status (TAS) were unaltered. Conclusions: Increment of oxidative stress in IIP seems to depend on enhancement of oxidants, rather than alteration of antioxidants. The issue that, elevated erythrocyte aggregation may further impair tissue oxygenation by disturbing microcirculation in IIP, may be considered in the follow up and development of new treatment protocols for this disease. © Mattioli 1885.

It is well known that hemostatic-thrombotic mechanisms are influenced by hemodynamic factors, such as shear forces affecting platelets or red blood cell aggregation, in turn affecting flow in stenotic regions. Endothelial cell function is also significantly influenced by shear forces acting on the vessel wall. Further, the distribution of shear forces in the vasculature is complex and closely associated with factors determining the flow properties of blood. Therefore, there is a link among alterations in the rheological properties of blood and its elements and the risk for thrombosis, with this linkage confirmed by numerous clinical studies. After discussing relevant rheological and hemodynamic concepts, this review focuses on selected drug-induced conditions that are known to be associated with both hyperviscosity conditions and increased thrombotic risk: oral contraceptives, diuretics, intravenous immunoglobulin, erythropoiesis-stimulating agents, chemotherapy, and radio-contrast media. Alterations of relationships between blood rheology and thrombotic risk related to artificial circulatory environments and physical exercise are also briefly discussed., NA

Background: Diagnosis of giant cell arteritis (GCA) is based on criteria of the American College of Rheumatology. However, not all GCA patients meet these criteria and treatment may be delayed in individual patients, leading to an increased risk of complications. Methods: In an observational study, we investigated acute phase response markers in GCA and non-GCA patients matched for erythrocyte sedimentation rate and CRP levels. Results: Plasma viscosity (PV) was significantly elevated in all GCA patients, but normal in non-GCA patients. Conclusions: Our data suggest that PV may reflect a more specific component of the acute inflammatory response in patients with GCA. Analysis of PV may significantly contribute to a reliable diagnosis early in the course of the disease, particularly in patients with suspected GCA that do not meet current diagnostic criteria.

Objective: The primary aim of this research is to systematically sort out and analyze available documents for yang deficiency syndrome in traditional Chinese medicine, providing innovative ideas and methods for statistical study of yang deficiency syndrome. Methods: Based on the China National Knowledge Internet (CNKI) and Chongqing VIP databases, using ”yang deficiency”, ”deficiency cold”, and ”patient” as keywords, we searched literature of clinical researches and used ”ratio-comparison” and ”integration-comparison” to analyze objective data after data preprocessing. Relative importance value of physiological and biochemical parameters were reflected by P value calculated by ratio-comparison or Q value by integration-comparison. Results: With calculation of relative importance values of clinical indicators among various systems, we got the ranking of relative importance of different indexes. Triiodothyronine and urine 17-hydorxycorticosteroid of endocrine system, immunoglobulin A of immune system, and the ratio of cyclic adenosine monophosphate to cyclic guanosine monophosphate, which had great |P|(or |Q|) values and negative P (or Q) values, had a clearly lower level in yang deficiency patients than in the control; hemorheological indicators such as plasma viscosity, whole blood reduced viscosity and erythrocyte electrophoresis time had small |P| (or |Q|) values. These indicators, however, showed less importance for reflecting yang deficiency. Conclusion: Ratio-comparison method and integration-comparison method employed in this study have merits of efficiency and robustness. After detailed compiling and mining of all available data, we have made reasonable advice on the most relevant index of yang deficiency for further study of the essence of this syndrome.

Background: Markers of platelet activation and haemorrheological indices have been demonstrated to play a role in the pathophysiology of atherosclerosis and cardiovascular events. In this study, we aimed at investigate the association between plasma viscosity and platelet indices in patients undergoing coronary angiography. Materials and methods: Three hundred and eighty four consecutive patients scheduled to undergo coronary angiography were included in the study. Prior to coronary angiography, blood samples were withdrawn to determine routine biochemical markers, blood cell analyses and viscosity measurements. According to the results of coronary angiography, patients were classified either in a subgroup with coronary artery disease (CAD; 1 or more stenoses > 50%) or normal coronary arteries (NCA; no stenoses or

To ascertain the effects of environmental temperature on blood rheology, ten subjects performed two exercise trials, in random order, at approximately 60% VO 2 max for 45-min. One trial was conducted in thermoneutral environment (20 ± 1°C), while the other was performed in hot dry condition (36 ± 1°C). Venous blood was removed at rest; following exercise and recovery. Blood was measured for lactate, haematocrit, and hemoglobin, while plasma was measured for viscosity, and fibrinogen. Plasma volume changes were estimated from Hct and Hb readings. Exercise was followed by a significant (P < 0.05) reduction in plasma volume in both test trials. Lactate increased significantly (P < 0.05) following exercise with no difference being observed between trials. When post exercise raw data were not adjusted for plasma volume changes, a significant increase (P < 0.05) in plasma viscosity (PV) and plasma fibrinogen (Fb) was found with no difference between thermoneutral and hot trials. When the raw data post exercise for PV and Fb were adjusted for plasma volume changes, no significant difference between rest and post exercise was demonstrated. Rheological variables returned to the pre-exercise level at the end of recovery. In conclusion, vigorous exercise transiently increased PV and Fb, and the added heat stress did not affect these responses more than exercise alone. The mechanism responsible for the increase in PV and Fb in response to vigorous exercise appears to be related to plasma shifts from intravascular to the extravascular spaces rather than plasma volume loss.

Purpose of review: Plasma expanders are reviewed to determine their ability to restore microvascular function as a means for extending the transfusion trigger and delaying the use of blood transfusions. This outcome is currently achievable because of the emergence of a new understanding of optimal tissue function that prioritizes maintenance of functional capillary density, which results from the normalization of blood viscosity via the increase in plasma viscosity with new viscogenic colloids. Recent findings: Use of viscous plasma expanders in experimental models of extreme hemodilution, hemorrhagic shock and endotoxemia shows that the limiting factor in anemia is not oxygen-carrying capacity but the decline of microvascular function due to the lowering of functional capillary density. In support of this hypothesis, we find that viscogenic colloids including high-molecular-weight starches, dextrans, polyvinylpyrrolidone, keratin and polyethylene glycol-conjugated albumin maintain or restore microvascular function in extreme hemodilution, polyethylene glycol-conjugated albumin yielding the best results. Summary: Preclinical studies show that polyethylene glycol-conjugated albumin at concentrations in the range of 2-4% extends the transfusion trigger, providing the more extended and complete microvascular and systemic recovery from hemorrhagic shock, extreme hemodilution and endotoxemia, postponing the need of reestablish intrinsic blood oxygen-carrying capacity to hemoglobin concentrations lower than those associated with accepted transfusion triggers.

Summary The erythrocyte sedimentation rate has previously been identified as an important prognostic factor in Hodgkin's disease. The plasma viscosity has replaced the ESR measurement in many laboratories, but doubts exist about its clinical relevance. In this study plasma viscosity at presentation/diagnosis was studied in 107 patients with Hodgkin's disease. A multivariate analysis of factors influencing prognosis and relapse-free survival identified plasma viscosity and number of disease sites as being highly significant. The risk of relapse increases initially with a rise in plasma viscosity, but after a value of about 2.0 mPa.s no further increase in risk is observed. When all of the prognostic factors are made available to the proportional hazards model, treatment modality and plasma viscosity are selected as the best set for predicting time to first relapse. This study demonstrates that measurement of plasma viscosity at presentation is an important prognostic factor in Hodgkin's disease, in terms of predicting outcome or risk of relapse.

Objective To determine if the time courses of hemorheologic parameters are different between carriers of sickle cell trait (SCT) and subjects with normal hemoglobin in response to exercise. Design Observational and comparative study. Setting Testing was conducted in a laboratory of exercise physiology. Participants Nine carriers of sickle cell trait (SCT group) and 7 subjects with normal hemoglobin (CONT group) performed an exercise protocol of the repetition of 3 successive maximal ramp exercise tests. Interventions Blood was sampled at rest (TR), at the end of each of the 3 tests (T1, T2, T3), and during the immediate (T2h) and late (T24h, T48h) recovery periods. Main outcome measurements Blood and plasma viscosity (etab and etap, respectively), hematocrit (Hct), and red blood cell (RBC) rigidity (Tk and k indexes) were determined. Results In both groups, etab significantly increased in response to exercise but the SCT group had significantly higher etab at T3 and T2h. etab then returned to baseline value at T2h in the CONT group and at T24h in the SCT group. Tk and k were not changed by exercise but significantly increased above baseline value in both groups at T24h and T48h. The increase in Tk and k during late recovery was higher in the SCT group than in the CONT group, indicating that SCT carriers had significantly higher RBC rigidity than the CONT group at that time. Conclusions The hemorheologic changes induced by exercise in the SCT carriers could trigger microcirculatory disorders during the recovery.

BACKGROUND: In microcirculation, the non-Newtonian behavior of blood and the complexity of the microvessel network are responsible for the high flow resistance and the large reduction of the blood pressure. Red blood cell aggregation along with inward radial migration are two significant mechanisms determining the former. Yet, their impact on hemodynamics in non-straight vessels is not well understood. OBJECTIVE: In this study, the steady state blood flow in stenotic rigid vessels is examined, employing a sophisticated non-homogeneous constitutive law. The effect of red blood cells migration on the hydrodynamics is quantified and the constitutive model's accuracy is evaluated. METHODS: A numerical algorithm based on the two-dimensional mixed finite element method and the EVSS/SUPG technique for a stable discretization of the mass and momentum conservation equations in addition to the constitutive model is employed. RESULTS: The numerical simulations show that a cell-depleted layer develops along the vessel wall with an almost constant thickness for slow flow conditions. This causes the reduction of the drag force and the increase of the pressure gradient as the constriction ratio decreases. CONCLUSIONS: Viscoelastic effects in blood flow were found to be responsible for steeper decreases of tube and discharge hematocrits as decreasing function of constriction ratio. © 2015 - IOS Press and the authors. 52 3 183 210 Cited By :2

Rheohaemapheresis aims to normalize major rheological parameters and is used to treat patients with dry age-related macular degeneration (AMD). While effective, this approach is invasive and requires specially trained personnel. Therefore, the search for novel effective compounds with hemorheological properties that can be taken orally to treat AMD is justified. The use of a robust rodent model of AMD with high blood viscosity is crucial to test the efficacy of potential hemorheological drugs to treat this disease. The objective of this study was to investigate whether OXYS rats, generally used as an animal model of AMD, have hyperviscosity syndrome. The results of this study show that blood viscosity in OXYS rats at low (3-10 s −1 ) and high (45-300 s −1 ) shear rates were 14-20% and 7-10% higher than in Wistar rats, while hematocrit and plasma viscosity were not different. Red blood cells (RBCs) in OXYS rats were more prone to aggregation as shown by 39% shorter half-time than in Wistar rats. RBCs were also more rigid in OXYS than in Wistar rats as shown by 21-33% lower index of elongation at the shear stress of 1-7 Pa. These data indicate that OXYS rats have hyperviscosity syndrome as the result of abnormal RBC deformability and aggregation. We propose to use OXYS rats as an animal model for preclinical studies to test compounds with hemorheological properties aimed to treat AMD.

We aimed to investigate the effects of vitamin B12 deficiency on hemorheological parameters, and the changes in these parameters following vitamin B12 treatment. 33 patients (mean-age:7±5.7 years) diagnosed as nutritional vitamin B12 deficiency, and 31 age and sex matched controls (mean-age:7.1±5.2 years) were enrolled. Erythrocyte deformability and aggregation were determined by an ectacytometer, plasma and whole blood viscosities by a cone-plate rotational viscometer. The differences between patients and controls were compared. Hemorheological parameters were repeated in the patient group following vitamin B12 treatment, and the results were compared with the initial results. In vitamin B12 deficiency, erythrocyte deformability and whole blood viscosity were found to be significantly decreased, eythrocyte aggregation was found to be significantly increased compared with the controls. Plasma viscosity was found to be decreased in deficiency but this decrease was not statistically significant. In patient group, erythrocyte deformability, whole blood and plasma viscosities were found to be significantly increased and erythrocyte aggregation was significantly decreased, after treatment. This study indicates that vitamin B12 deficiency has important effects on hemorheological parameters and adequate treatment of deficiency not only corrects the hematological parameters, but also by helping to normalize the hemorheological parameters, may contribute to the regulation of microvascular perfusion. © 2015 - IOS Press and the authors. All rights reserved.

OBJECTIVE:We aimed to investigate the effects of iron deficiency anemia (IDA) and vitamin B12 deficiency coexisting with IDA which is called as mixed anemia (MA) on hemorheological parameters, to compare them with each other and healthy controls, and to assess the changes in hemorheological parameters after treatment. MATERIALS AND METHODS: 32 IDA patients (mean age:6.3±5.3 years), 30 MA patients (mean age:7.2±5.4 years), and 31 healthy controls (mean age:7.1±5.2 years) were enrolled. Erythrocyte deformability and aggregation were determined by an ectacytometer, plasma and whole blood viscosities by a cone-plate rotational viscometer. Differences between IDA and MA, and healthy controls were compared. Hemorheological parameters were repeated in the patient groups after treatment and compared with the initial results. RESULTS: In both of the patient groups, erythrocyte deformability, whole blood and plasma viscosities were found to be significantly decreased before treatment, compared with the controls. After treatment these parameters were found to be increased significantly. There were no significant differences in these parameters between the IDA and MA group. Additionally, no statistically significant alteration was found in erythrocyte aggregation measurements of both patient groups. CONCLUSION: This study indicates that IDA andMAhave similar effects on hemorheological parameters. When vitamin B12 deficiency accompanies IDA which is called as MA, no further alterations occur in hemorheological parameters. The adequate treatment of these anemias not only corrects the hematological parameters, but also by helping to normalize the hemorheological parameters, may contribute to the regulation of microvascular perfusion. © 2015 - IOS Press and the authors.

SummaryThe interactions of epilepsy and antiepileptic therapy an one hand and cardiovascular system on the other hand are multiple and complex. Antiepileptic drugs (AEDs) cause alterations of serum lipids and of the fatty acid composition of the membranes. Homocystein, known to induce vascular endothelial damage was found to be elevated in patients on valproate (VPA) and carbamazepine (CBZ) therapy. Marked coronary artherosclerosis and myocardial infarction may already occur in children treated with CBZ. Community based studies corroborated a higher incidence of myocardial infarction, peripheral vascular diseases hypercholesterinemia, left ventricle hypertrophy and stroke in patients with epilepsy. In this context, we wanted to elevate changes of microcirculation related to AEDs commonly prescribed such as VPA and CBZ.Capillary microscopy is a non-invasive technique for measuring the velocity of red blood cells and for determining nutritional blood flow in the capillaries of the skin. It can easily be performed in children.The aim of this study was to look for possible effects an antiepileptic monotherapy with carbamazepine or valproate has on the peripheral microcirculation in epileptic children.We were able to examine 14 children with CBZ and 24 children with VPA, recruited in our neuropediatric Unit. The results were compared to normative values, determined in former analyses of 207 healthy children. We found significant differences in capillary density, tortuous index of the capillaries, capillary diameter and flow rate of erythrocytes for both antiepileptic drugs. Additionally, there were changes in plasma viscosity and the aggregation of erythrocytes.These microcapillary effects could be of special interest in the relationship of a long-term antiepileptic therapy and the development of vascular diseases.We suggest that the influence of AEDs on microcirculation should also be considered in further studies on cardiovascular changes in patients with antiepileptic long-term medication.

BACKGROUND: Acute hemorheological responses to different types of aerobic exercises have never been compared in a single study in healthy people., OBJECTIVE: We aimed to compare acute effects of high intensity intermittent exercise (HIIE) and moderate intensity continuous exercise (MICE) on hemorheological parameters, in healthy young subjects., METHODS: A total of 34 sedentary young adults (12 males, 22 females) with a mean age of 20.0±2.1 years were randomly assigned to HIIE, MICE or non-exercise groups. MICE exercised at the power corresponding to 50% of heart rate reserve (HRR) continuously for 25 min. HIIE exercised at the power corresponding to 100% of HRR for 30 s followed by 30 s rest for 25 min. The non-exercise group rested. Blood samples were collected before and after exercise and studied for blood count, whole blood viscosity (WBV), plasma viscosity (PV) and red blood cell (RBC) elongation at nine different shear stresses., RESULTS: WBV, PV, RBC elongation of MICE and HIIE groups were not found to be statistically different from each other or from the non-exercise group. Compared to the non-exercise group, there was a significant increase in white blood cell (WBC) and RBC counts in the MICE group., CONCLUSIONS: Different types of aerobic exercises, namely MICE, HIIE are not different from each other in terms of hemorheological parameters immediately after exercise. © 2014-IOS Press and the authors.

Intravenous immunglobulin (IVIg) is used to treat a number of immune-deficiences and autoimmune diseases. Safety concerns related to a number of reported thromboembolic complications prompted us to review the literature. These complications happened mainly in individuals that had risk factors for thromboembolism, like advanced age, previous thromboembolic diseases, bed-ridden, and in individuals in which high doses or high infusion rates of IVIg were administered. The mechanism responsible for these events seems to be a rise in plasma viscosity that can trigger a thromboembolic event, especially in cases in which there is an underlying circulation impairment. Complications can be minimized by using IVIg only in clear-cut indications, weighting risk versus benefit in patients who are at high risk for thromboembolism and by sticking to carefully monitored slow infusion rates. IVIg for the treatment of autoimmune disorders should be administered as a five-day course of 2 g/kg of body weight. Each daily dose of 400 mg/kg should be given in not less than eight hours.

To examine the social, biological, and metabolic associations of plasma viscosity in a large epidemiological study.Plasma viscosity was measured from 4548 men and 1837 women that took part in the fifth phase of the Whitehall II Study (1997-1999). Employment grade was used as a measure of social position.A strong inverse relation between employment grade and plasma viscosity was evident (p0.0001). This employment grade gradient was apparent overall, and among non-smokers and when participants with poor health were removed from the analyses. Plasma viscosity was associated with a number of biological factors that are themselves socially determined, including fibrinogen (p0.001), triglycerides (p0.001), fasting insulin (p0.001), and height (p0.001). Associations with smoking and alcohol intake were apparent in women. In men a U-shaped curve was apparent such that those drinking between 11 and 24 units/week had the lowest plasma viscosity. Alcohol intake, physical activity, and smoking explained 18% of the grade gradient in men and 40% in women while the biological factors examined accounted for 35% in men and 40% in women.There is a grade gradient in plasma viscosity which was not fully explained by health related behaviors or measured risk factors for CHD. These data suggest that additional factors that contribute to the rheological properties of plasma may contribute to the explanation for social inequalities in cardiovascular disease.

To evaluate whether the use of transdermal hormone replacement therapy (HRT), in women within 5 years of menopause compared with women who were postmenopausal for5 years, would significantly influence thromboxane B2 levels, plasma viscosity and Doppler flow parameters at the level of the uterine, internal carotid, ophthalmic and bladder wall arteries.Thirty-five normal-weight (body mass index19 and25 kg/m(2)) postmenopausal women (age 54.6 +/- 3.9 years, mean +/- standard deviation) participated in the study and were divided into two groups (Group I: n = 19, time since menopause5 years; and Group II: n = 16, time since menopause5 years). Patients were treated with a continuous estradiol transdermal supplementation and 12-day courses of medroxyprogesterone acetate every 2 months. They were studied at baseline and after 6 months (in the estrogen-only phase of the cycle).Results showed a beneficial effect of hormone substitution after 6 months of therapy. Baseline plasma viscosity was similar in both groups, and decreased significantly after therapy in both Group I (-17.5%) and Group II (-15.6%). Plasma levels of thromboxane B(2) were similar at baseline and diminished equally in Group I and Group II (-85.6% and -85.2%, respectively) after treatment. Doppler assessment of the pulsatility index at the level of uterine, internal carotid, ophthalmic and bladder wall arteries showed no differences between groups at baseline and revealed a significant reduction of vascular impedance at the end of the treatment in both groups.Time since menopause does not affect the potential hemodynamic benefits of HRT in normal-weight women.

Plasmapheresis is a widely used alternative treatment for several diseases. Recently, synthetic plasma expanders have been used to reduce the cost of therapeutic plasma exchange (TPE). Hydroxyethyl starch (HES) is a polysaccharide colloid. Isohes and Varihes are plasma volume expanders containing 6% HES in 0.9% NaCl solution. In this study, we aimed to compare the effects of several replacement fluids used for TPE on plasma viscosity profile. At the same time, we evaluated the correlation between plasma viscosity and fibrinogen level. Twenty-nine patients were enrolled for this study. Patients were divided into four groups based on replacement fluids used: 3% HES + 4% albumin (group 1), FFP (group 2), 3% Varihes (450 000/0.7)/Isohes(200 000/0.5) (group 3), and 4% albumin (group 4). The choice of replacement fluids used was randomly assigned, as long as there were no contraindications for the patient. Seven samples were collected to determine plasma viscosity and fibrinogen level during TPE cycles. There was a positive exponential correlation between plasma viscosity and fibrinogen levels. At the second plasmapheresis procedure, plasma viscosity and fibrinogen levels decreased by 20% compared with first cycle. The effect of plasmapheresis solutions on hemorheology were roughly the same. Effects of replacement fluids on plasma viscosity were comparable.

In January 1985 an extended smog episode occurred in Central Europe. The Rhine-Ruhr area (Western Germany) was affected for 5 days with maximum concentrations of 0.8 mg/m3 SO2 and 0.6 mg/m3 TSP (24h averages). Health effects were investigated during the smog period and a control period before and after the smog. Daily mortality increased by 8%, hospital admissions (for respiratory and cardiovascular causes, RC) by 15%, outpatients (RC) by 12% and ambulance transports (RC) by 28%. Patients with chronic bronchitis from the Ruhr area cities showed more exacerbations during the episode, and in school children from the Netherlands lung function was reduced. In Augsburg (Southern Germany) the smog episode was less severe (maximum concentrations 0.2 mg/m3 SO2 and 0.1 mg/m3 TSP, 24 h averages). Here--by chance--the prospective MONICA study was ongoing. During the episode a significant increase of plasma viscosity, C-reactive protein and heart rate was observed in the participants. The highest ambient concentrations (maximum 24h average of 3.6 mg/m3 SO2) were measured in Erfurt (Eastern Germany). Surprisingly, no measurable increase of mortality occurred. This was explained by premature deaths during the period before the smog, were the concentrations had already been clearly above 1 mg/m3 SO2. An earlier episode took place in December 1962 in the Rhine-Ruhr area for 5 days with maximum concentrations of 5.0 mg/m3 SO2 and 2.4 mg/m3 TSP (24 h average). Daily mortality on average increased by 19%. In 1962 and 1985 the effects were stronger in cities with pollution mainly from traffic than in areas with pollution from industrial sources. In total, between 1962 and 1987 two major and several smaller smog episodes occurred in Central Europe. Patients with cardiovascular diseases were more severely affected than patients with respiratory diseases. Health effects were more strongly correlated with TSP than with SO2.

AIMS: Aim of the study was to investigate the association between various markers of systemic inflammation and a detailed history of smoking in a large representative sample of the general population. METHODS AND RESULTS: The effects of chronic smoking on white blood cell (WBC) count, fibrinogen, albumin, plasma viscosity (PV), and high-sensitivity C-reactive protein (CRP) were measured in 2305 men and 2211 women, age 25-74 years, participating in the third MONICA Augsburg survey 1994/95. In men, current smokers showed statistically significantly higher values for WBC count, fibrinogen, PV, and CRP, compared to never smokers, with intermediate, but only slightly increased values for ex-smokers and for occasional smokers. No consistent associations were seen with albumin. Duration of smoking was positively associated with markers of inflammation as were pack-years of smoking. Conversely, duration of abstinence from smoking was inversely related to these markers. Except for WBC count, no such associations were found in women. CONCLUSION: Data from this large representative population show strong associations between smoking and various markers of systemic inflammation in men. They also show that cessation of smoking is associated with a decreased inflammatory response, which may represent one mechanism responsible for the reduced cardiovascular risk in these subjects.