| 1. |
- Beshara, Soheir, et al.
(author)
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Anemia associated with advanced prostatic adenocarcinoma : Effects of recombinant human erythropoietin
- 1997
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In: The Prostate. - 0270-4137 .- 1097-0045. ; 31:3, s. 153-160
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Journal article (peer-reviewed)abstract
- BACKGROUND AND METHODS: Nine patients with hormone-refractory metastatic prostatic adenocarcinoma and anemia were treated with recombinant human erythropoietin (rHuEpo) at a median dose of 150 U/kg BW 3 times a week subcutaneously. Baseline hemoglobin (Hb) ranged from 70 to 116 g/L, and the study duration was 12 weeks (median patient participation period was 8 weeks). RESULTS: Four patients demonstrated a median Hb increase of 20 g/L and were considered responders. Three patients showed a median increase of 17 g/L but required blood transfusion once, and were therefore considered as partial responders. Baseline erythropoietic status showed a significant correlation between serum Epo and Hb. Inadequate Epo production, evaluated by the observed/predicted log Epo ratio, was found in two patients. Defective bone marrow activity, demonstrated by low transferrin receptor (TfR), and hypoferremia in spite of abundant iron stores were also shown. Hemorheological investigations showed elevated plasma viscosity. CONCLUSIONS: Our results indicate that suppression of erythropoiesis can be mainly explained by the depressed marrow activity. The altered hemorheology might contribute to the anemia. This anemia could possibly be corrected with rHuEpo.
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| 2. |
- Fadul, Jamal E., et al.
(author)
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Effects of LDL apheresis on blood rheology in two patients with homozygous familial hypercholesterolaemia
- 1997
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In: Blood Purification. - 0253-5068 .- 1421-9735. ; 15:3, s. 182-187
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Journal article (peer-reviewed)abstract
- Changes in haemorheological and lipid variables were investigated in 2 patients with homozygous familial hypercholesterolaemia (FH) treated with low-density lipoprotein (LDL) apheresis using dextran sulphate adsorbent. The immediate effect of LDL apheresis was a fall in plasma fibrinogen by 50%, total and LDL cholesterol by 60%, plasma viscosity by 12% and whole blood viscosity by 17%. Before the 12th treatment session, plasma fibrinogen concentration remained reduced by 22%, whole blood viscosity by 17% and the plasma viscosity by 11% compared with the initial values. Total and LDL cholesterol in plasma also remained reduced by about 50%. We conclude that LDL apheresis, using dextran sulphate adsorbent, improves blood rheology. The decrease in plasma fibrinogen concentrations, plasma viscosity and LDL cholesterol might be factors contributing to the improved haemorheological properties.
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| 3. |
- Fadul, Jamal E. M., et al.
(author)
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Effects of extracorporeal hemapheresis therapy on blood rheology
- 1997
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In: Journal of clinical apheresis. - 0733-2459 .- 1098-1101. ; 12:4, s. 183-186
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Journal article (peer-reviewed)abstract
- The blood flow property is one of the factors determining blood perfusion and oxygen supply. The viscosity of the blood is primarily related to the hematocrit, but also to the amount of fibrinogen and other macromolecules present in the blood. Patients with ischemic heart disease have shown a rapid and safe improvement in their hemorheological state when treated with heparin-induced extracorporeal low-density lipoprotein (LDL) precipitation (HELP). In this study we used two extracorporeal hemapheresis methods, plasmapheresis (PP) and immunoadsorption (IA), in 15 patients (eight patients treated with PP and seven patients with IA) with various diseases. Hemorheological variables and plasma fibrinogen were measured before and after the first and before the third treatment performed at 3 consecutive days. The aim of our study was to investigate the immediate effects of these two treatment modalities on the flow properties of blood. Immediately after the first PP and IA session statistically significant declines in plasma fibrinogen concentration, plasma viscosity, whole blood viscosity, and erythrocyte aggregation tendency were found. These changes persisted before the third treatment session. The erythrocyte fluidity and hematocrit remained unchanged. We conclude that extracorporeal hemapheresis therapy, with plasmapheresis or immunoadsorption, affects the blood rheology by decreasing the plasma viscosity and erythrocyte aggregation tendency. The decrease in plasma fibrinogen is probably the main factor underlying that, but other factors such as a decrease in immunoglobulins may also be of importance.
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| 4. |
- Linde, Torbjörn, et al.
(author)
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Decreased blood viscosity and serum levels of erythropoietin after anti-hypertensive treatment with amlodipine or metoprolol : results of a cross-over study
- 1996
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In: Journal of Human Hypertension. - 0950-9240 .- 1476-5527. ; 10:3, s. 199-205
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Journal article (peer-reviewed)abstract
- The increased viscosity of blood of hypertensive patients can be assumed to be a risk factor for the development of cardiovascular diseases. The aim of the present study was to elucidate whether anti-hypertensive treatment has any impact on blood theology. Twenty patients with previously untreated hypertension who consecutively attended our outpatient hypertension clinic were included in this prospective, open, cross-over study. The patients were randomly selected to treatment with amlodipine or metoprolol. The antihypertensive therapy was switched after 4 months. Haemorheological and haemodynamic variables were measured with rotational viscometry and impedance cardiography, respectively. Fifteen and 16 patients could be evaluated after amlodipine or metoprolol treatment respectively. The mean blood pressure (BP) decreased from 159 +/- 22/105 +/- 7 to 139 +/- 21/91 +/- 6 mm Hg on amlodipine and from 162 +/- 22/104 +/- 5 to 145 +/- 24/90 +/- 8 mm Hg on metoprolol therapy. After amlodipine treatment, the total peripheral resistance index decreased whereas metoprolol treatment was accompanied by a decrease in the cardiac index. Decreases in whole blood viscosity, haematocrit and serum erythropoietin were found after amlodipine as well as metoprolol treatment. After amlodipine the plasma viscosity decreased and the erythrocyte deformability increased in the majority of patients. Plasma fibrinogen decreased after metoprolol treatment. Despite the differences in haemodynamic mechanisms underlying the decrease in BP, amlodipine and metoprolol exert beneficial effects on blood viscosity. Haemodilution and a decrease in serum erythropoietin may be factors underlying this decrease in blood viscosity.
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| 5. |
- Linde, Torbjörn, et al.
(author)
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The required dose of erythropoietin during renal anaemia treatment is related to the degree of impairment in erythrocyte deformability
- 1997
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In: Nephrology, Dialysis and Transplantation. - 0931-0509 .- 1460-2385. ; 12:11, s. 2375-2379
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Journal article (peer-reviewed)abstract
- BACKGROUND: Renal anaemia is rapidly corrected by recombinant human erythropoietin (rHuEpo) therapy, but the dose required varies greatly. Since impaired erythrocyte deformability may be one factor contributing to the development of renal anaemia, the interrelationship between that variable and the rHuEpo requirement was examined. METHODS: Twenty-five patients treated with hemodialysis and rHuEpo for at least 6 months were included in the study. The Hb value had been stable and the rHuEpo dose unchanged the last two months. Using a rotational viscometer, the fluidity of erythrocytes, separated from plasma and re-suspended in isotonic buffered saline to a standardized haematocrit, was taken as a measure of erythrocyte deformability. RESULTS: The average weekly dose of s.c. epoetin alpha was 186 +/- 93 U/kg body weight (range 56-370). The dose was correlated to the reticulocyte fraction (R = 0.69, P = 0.0001). When the rHuEpo dose was used as dependent variable and blood haemoglobin concentration, serum (S) albumin, S ferritin, S aluminium, S PTH, S urea, Kt/V/week, erythrocyte fluidity, and plasma viscosity were used as independent variables in a stepwise multiple regression analysis, only erythrocyte fluidity remained significantly negatively correlated to the rHuEpo dose (R = 0.5, P = 0.01). Despite a tendency towards higher doses of rHuEpo in patients with a C-reactive protein concentration exceeding 20 mg/l, the Hb was lower in these patients. CONCLUSIONS: We conclude that the interindividual differences in bone marrow response to rHuEpo were small in these patients. Impaired erythrocyte deformability and inflammation seem to be factors associated with increased rHuEpo requirement.
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| 6. |
- Metry, George, et al.
(author)
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Effect of normalization of hematocrit on brain circulation and metabolism in hemodialysis patients
- 1999
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In: Journal of the American Society of Nephrology. - 1046-6673 .- 1533-3450. ; 10:4, s. 854-863
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Journal article (peer-reviewed)abstract
- Full correction of anemia with recombinant human erythropoietin (rhEPO) has been reported to reduce the risk of cardiovascular morbidity and mortality and improve the quality of life in hemodialysis (HD) patients. Effects of normalization of hematocrit on cerebral blood flow and oxygen metabolism were investigated by positron emission tomography. Regional cerebral blood flow (rCBF), cerebral blood volume (rCBV), oxygen extraction ratio (rOER), and metabolic rate for oxygen (rCMRO2) were measured in seven HD patients before and after correction of anemia and compared with those in six healthy control subjects. In addition, blood rheology before and on rhEPO therapy was measured in HD patients, which included blood viscosity, plasma viscosity, erythrocyte fluidity, and erythrocyte aggregability. The results showed that plasma viscosity was high (1.51+/-0.19 mPa x s) and erythrocyte fluidity was low (85.8+/-4.8 Pa(-1) x s(-1)), while whole blood viscosity was within the normal range (3.72+/-0.38 mPa x s) before rhEPO therapy. After treatment, the hematocrit rose significantly from 29.3+/-3.3 to 42.4+/-2.2% (P<0.001), accompanied by a significant increase in the whole blood viscosity to 4.57+/-0.16 mPa x s, nonsignificant decrease in erythrocyte fluidity to 79.9+/-7.4 mPa(-1) x s(-1) and nonsignificant change in plasma viscosity (1.46+/-1.3 mPa x s). Positron emission tomography measurements revealed that by normalization of hematocrit, rCBF significantly decreased from 65+/-11 to 48+/-12 ml/min per 100 cm3 (P<0.05). However, arterial oxygen content (caO2) significantly increased from 5.7+/-0.7 to 8.0+/-0.4 mmol/L (P<0.0001), rOER of the hemispheres significantly increased from 44+/-3 to 51+/-6% (P<0.05) and became significantly higher than healthy control subjects (P<0.05). In addition, rCBV significantly increased from 3.5+/-0.5 to 4.6+/-0.6 ml/100 cc brain tissue. The results showed that oxygen supply to the brain tissue increased with normalization of hematocrit, but it was accompanied by increased oxygen extraction in the brain tissue. This may be assumed to be related to the decrease of erythrocyte velocity in the cerebral capillaries as a result of the decreased blood deformability and the increased plasma viscosity.
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| 7. |
- Linde, Torbjörn, et al.
(author)
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Altered flow properties of blood and increased plasma fibrinogen in cyclosporin treated renal allograft recipients
- 1999
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In: Nephrology, Dialysis and Transplantation. - 0931-0509 .- 1460-2385. ; 14:6, s. 1525-1529
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Journal article (peer-reviewed)abstract
- BACKGROUND: Abnormalities in blood rheology may be factors contributing to cardiovascular complications and the progression of renal failure in kidney allograft recipients. The haemorheological variables haematocrit, fibrinogen, whole blood viscosity, plasma viscosity, erythrocyte aggregation tendency and fluidity were measured in 27 cyclosporin A (CyA)-treated patients who had received a renal graft at least 6 months previously. Their creatinine clearance was in the range of 12-92 ml/min/1.73 m2 (mean 55+/-19). The values were compared with those obtained from a control group comprising 20 healthy subjects matched according to age, sex and smoking habits. RESULTS: The haematocrit, plasma fibrinogen, whole blood viscosity, plasma viscosity, erythrocyte aggregation tendency, body mass index (BMI), mean arterial pressure (MAP) and serum triglycerides were increased in the transplanted patients, and the serum high density lipoprotein (HDL)-cholesterol and erythrocyte fluidity decreased. The haemorheological variables were used as dependent variables in a stepwise regression analysis with age, MAP, BMI, urinary albumin excretion rate, blood CyA concentration, creatinine clearance, and serum triglycerides, cholesterol and HDL-cholesterol as independent variables. Plasma fibrinogen was positively correlated with BMI and blood CyA. The whole blood viscosity was positively correlated with blood CyA and negatively with serum HDL-cholesterol. Only serum triglycerides remained correlated with erythrocyte aggregation tendency. CONCLUSIONS: All variables with a known impact on blood viscosity were altered in the present group of renal transplant recipients. Inappropriate regulation of erythrocyte formation, overweight, the use of CyA, high triglycerides and low HDL-cholesterol levels may be factors contributing to this. The importance of impaired flow properties of blood for the development of cardiovascular diseases and transplant glomerulosclerosis needs to be examined.
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