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EPO
Kinds of EPO Terms modified by EPO Selected AbstractsSDS-PAGE of recombinant and endogenous erythropoietins: benefits and limitations of the method for application in doping controlDRUG TESTING AND ANALYSIS, Issue 1 2009Christian Reichel Abstract Doping of athletes with recombinant and genetically modified erythropoietins (EPO) is currently detected by isoelectric focusing (IEF). The application of these drugs leads to a significant change in the isoform profile of endogenous urinary erythropoietin (uhEPO). Dynepo, MIRCERA, biosimilars with variable IEF-profiles as well as active urines and effort urines have made additional testing strategies necessary. The new generation of small molecule EPO-receptor stimulating agents like Hematide will also challenge the analytical concept of detecting the abuse of erythropoiesis stimulating agents (ESA). By determining their apparent molecular masses with SDS-PAGE a clear differentiation between endogenous and exogenous substances also concerning new EPO modifications is possible. Due to the orthogonal character of IEF- and SDS-PAGE both methods complement each other. The additional benefits of SDS-PAGE especially in relation to active and effort urines as well as the detection of Dynepo were investigated. Due to significant differences between the apparent molecular masses of uhEPO/serum EPO (shEPO) and recombinant, genetically or chemically modified erythropoietins the presence of active or effort urines was easily revealed. The characteristic band shape and apparent molecular mass of Dynepo on SDS-PAGE additionally evidenced the presence of this substance in urine. A protocol for the detection of EPO-doping in serum and plasma by SDS-PAGE was developed. Blood appears to be the ideal matrix for detecting all forms ESA-doping in the future. Copyright © 2009 John Wiley & Sons, Ltd. [source] Chronic erythropoietin treatment affects different molecular pathways of diabetic cardiomyopathy in mouseEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 9 2009N. Shushakova Abstract Background, Recent studies in mice experimental models with acute ischaemic injury revealed that erythropoietin (EPO) has numerous tissue-protective effects in the heart, brain and kidneys. We therefore explored the tissue-protective properties of chronic EPO treatment in an experimental model of the db/db mouse with diabetic heart injury. Material and methods, We randomly treated 11 db/db mice with placebo (saline), 0·4 ,g of the continuous erythropoietin receptor activator (CERA) per week (n = 11) or 1·2 ,g CERA per week (n = 11) for 14 weeks, and analysed cardiac tissue. The lower CERA dose was a non-haematologically effective dose, whereas the second increased the haematocrit. Results, Compared with mice in the placebo group, CERA-treated mice had a reduction in TGF-,1 and collagen I expression in cardiac tissue (P < 0·01 vs. higher dose CERA). In addition, an increased expression of the pro-survival intracellular pathway p-AKT was observed (P < 0·05 vs. higher dose CERA). The values for the lower C.E.R.A had an intermediate nonsignificant effect. Furthermore, we were able to show that atrial natriuretic peptide (ANP) expression was increased in both CERA groups. Conclusions, Chronic treatment with CERA protects cardiac tissue in diabetic animals, i.e. it inhibits molecular pathways of cardiac fibrosis, and the effects are dose-dependent. [source] Regulation of erythropoietin productionEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 2005K.-U. Eckardt Abstract The glycoprotein hormone erythropoietin (EPO) is an essential growth and survival factor for erythroid progenitor cells, and the rate of red blood cell production is normally determined by the serum EPO concentration. EPO production is inversely related to oxygen availability, so that an effective feedback loop is established, which controls erythropoiesis. Since recombinant EPO became available as an effective therapeutic agent, significant progress has also been made in understanding the basis of this feedback control. The main determinant of EPO synthesis is the transcriptional activity of its gene in liver and kidneys, which is related to local oxygen tensions. This control is achieved by hypoxia-inducible transcription factors (HIF), consisting of a constitutive ,-subunit and one of two alternative oxygen-regulated HIF, subunits (HIF-1, and HIF-2,). In the presence of oxygen (normoxia) the HIF, subunits are hydroxylated, which targets them for proteasomal degradation. Under hypoxia, because of the lack of molecular oxygen, HIF cannot be hydroxylated and is thereby stabilized. Although HIF-1, was the first transcription factor identified through its ability to bind to an enhancer sequence of the EPO gene, more recent evidence suggests that HIF-2, is responsible for the regulation of EPO. Although EPO is a prime example for an oxygen- regulated gene, the role of the HIF system goes far beyond the regulation of EPO, because it operates widely in almost all cells and controls a broad transcriptional response to hypoxia, including genes involved in cell metabolism, angiogenesis and vascular tone. Further evidence suggests that apart from its effect as an erythropoietic hormone EPO acts as a paracrine, tissue-protective protein in the brain and possibly also in other organs. [source] Recombinant human erythropoietin suppresses symptom onset and progression of G93A-SOD1 mouse model of ALS by preventing motor neuron death and inflammationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2007Seong-Ho Koh Abstract Multifactorial pathogenic mechanisms, including inflammation, attenuated survival signals and enhanced death signals, are involved in amyotrophic lateral sclerosis (ALS). Erythropoietin (EPO) has recently been highlighted as a cytokine with various potent neuroprotective effects, including reduction of inflammation, enhancement of survival signals and prevention of neuronal cell death. This study was undertaken to evaluate the effect of recombinant human EPO (rhEPO) on ALS model mice. We treated 96 ALS model mice with vehicle only, or 1, 2.5 or 5 iµ of rhEPO/g of mouse once every other week after they were 60 days old. The treatment significantly prolonged symptom onset and life span, preserved more motor neurons, enhanced survival signals, and attenuated inflammatory signals in a dose-dependent manner. These data suggest that treatment with rhEPO represents a potential therapeutic strategy for ALS. [source] The skin as a biofactory for systemic secretion of erythropoietin: potential of genetically modified keratinocytes and fibroblastsEXPERIMENTAL DERMATOLOGY, Issue 6 2008Frank Scheidemann Abstract Background:, The skin is an interesting target tissue for gene therapy applications because of its ready accessibility. One possibility would be to utilize the genetically modified skin as a biofactory secreting a systemically needed product, such as erythropoietin (EPO). Methods:, Keratinocytes (KC) and fibroblasts (FB) were transduced with a retroviral vector encoding human EPO. Gene transfer efficiency was assessed by real-time PCR analysis and flow cytometry of transduced cells. In addition, EPO synthesis and secretion were analysed by quantifying the amount of RNA and secreted protein in both monolayer cultures and skin equivalents (SE). Results:, When cultured as a monolayer, EPO-KC synthesized significantly more EPO than EPO-FB, as shown by quantitatively measuring the amount of secreted protein and RNA. This correlated with an increased EPO-vector incorporation in KC compared with FB, demonstrated by determining both the percentage of transduced cells and the average transgene copy number per cell. In addition, in transduced cell cultures enriched to equally high percentages of EPO+ cells, KC showed a higher activity of EPO secretion than FB. Finally, when assembled in a SE, EPO-KC secreted significantly higher amounts of EPO than EPO-FB, although reduced secretory activity of EPO-KC monolayers grown in high calcium concentrations suggested that in stratified epidermis differentiated KC secrete less EPO than non-differentiated KC. Conclusion:, In summary, while both transduced KC and FB are able to synthesize and secrete human EPO, KC show higher potential in serving as possible target cells for therapeutic substitution with EPO, probably because of improved transduction rates and increased secretory activity. [source] Redox properties of the couple compound I/native enzyme of myeloperoxidase and eosinophil peroxidaseFEBS JOURNAL, Issue 19 2001Jürgen Arnhold The standard reduction potential of the redox couple compound I/native enzyme has been determined for human myeloperoxidase (MPO) and eosinophil peroxidase (EPO) at pH 7.0 and 25 °C. This was achieved by rapid mixing of peroxidases with either hydrogen peroxide or hypochlorous acid and measuring spectrophotometrically concentrations of the reacting species and products at equilibrium. By using hydrogen peroxide, the standard reduction potential at pH 7.0 and 25 °C was 1.16 ± 0.01 V for MPO and 1.10 ± 0.01 V for EPO, independently of the concentration of hydrogen peroxide and peroxidases. In the case of hypochlorous acid, standard reduction potentials were dependent on the hypochlorous acid concentration used. They ranged from 1.16 V at low hypochlorous acid to 1.09 V at higher hypochlorous acid for MPO and from 1.10 V to 1.03 V for EPO. Thus, consistent results for the standard reduction potentials of redox couple compound I/native enzyme of both peroxidases were obtained with all hydrogen peroxide and at low hypochlorous acid concentrations: possible reasons for the deviation at higher concentrations of hypochlorous acid are discussed. They include instability of hypochlorous acid, reactions of hypochlorous acid with different amino-acid side chains in peroxidases as well as the appearance of a compound I,chloride complex. [source] The relationship between fishing methods, fisheries management and the estimation of maximum sustainable yieldFISH AND FISHERIES, Issue 4 2002Mark N Maunder Abstract The allocation of effort among fishing gears is as important as controlling effort with respect to both sustainable yield and ecosystem management. Differences in age-specific vulnerability to the fishing method can modify the maximum sustainable yield (MSY) that is obtainable from a fish stock. Different gears or methods are more or less selective for the species targeted, and MSY is rarely, if ever, attainable simultaneously for all species. The different fishing methods capture different types of nontarget species. Some methods will often be more profitable than others, and different user groups will prefer different methods. In many fisheries, it is unlikely that fishing can be limited to a single gear or method, so compromises among them will be required. Global MSY is discussed as a possible reference point for fisheries management. The yellowfin tuna fishery in the eastern Pacific Ocean (EPO) shows all the above characteristics and is used to illustrate effort allocation among fishing methods. [source] Application of a habitat-based model to estimate effective longline fishing effort and relative abundance of Pacific bigeye tuna (Thunnus obesus)FISHERIES OCEANOGRAPHY, Issue 3 2002Keith A. Bigelow A new habitat-based model is developed to improve estimates of relative abundance of Pacific bigeye tuna (Thunnus obesus). The model provides estimates of `effective' longline effort and therefore better estimates of catch-per-unit-of-effort (CPUE) by incorporating information on the variation in longline fishing depth and depth of bigeye tuna preferred habitat. The essential elements in the model are: (1) estimation of the depth distribution of the longline gear, using information on gear configuration and ocean currents; (2) estimation of the depth distribution of bigeye tuna, based on habitat preference and oceanographic data; (3) estimation of effective longline effort, using fine-scale Japanese longline fishery data; and (4) aggregation of catch and effective effort over appropriate spatial zones to produce revised time series of CPUE. Model results indicate that effective effort has increased in both the western and central Pacific Ocean (WCPO) and eastern Pacific Ocean (EPO). In the WCPO, effective effort increased by 43% from the late 1960s to the late 1980s due primarily to the increased effectiveness of effort (deeper longline sets) rather than to increased nominal effort. Over the same period, effective effort increased 250% in the EPO due primarily to increased nominal effort. Nominal and standardized CPUE indices in the EPO show similar trends , a decline during the 1960s, a period of stability in the 1970s, high values during 1985,1986 and a decline thereafter. In the WCPO, nominal CPUE is stable over the time-series; however, standardized CPUE has declined by ,50%. If estimates of standardized CPUE accurately reflect relative abundance, then we have documented substantial reductions of bigeye tuna abundance for some regions in the Pacific Ocean. A decline in standardized CPUE in the subtropical gyres concurrent with stability in equatorial areas may represent a contraction in the range of the population resulting from a decline in population abundance. The sensitivity of the results to the habitat (temperature and oxygen) assumptions was tested using Monte Carlo simulations. [source] Effect of improvement in anemia on electroneurophysiological markers (P300) of cognitive dysfunction in chronic kidney diseaseHEMODIALYSIS INTERNATIONAL, Issue 3 2006Narinder P. SINGH Abstract Our aim is to study the effect of improvement in anemia on event-related potentials (ERPs; P300) as markers of cognitive dysfunction in predialysis and dialysis patients of chronic kidney disease (CKD). Thirty anemic patients of CKD (hemoglobin [Hb]<9 g%), 15 in the predialysis group (Group A), and 15 patients on biweekly hemodialysis (Group B) were recruited for the study. Patients of uremic encephalopathy, dyselectrolytemia, and those with hearing problems were excluded. Both groups were given recombinant human erythropoietin (rhuEPO) 100 IU/kg biweekly for 6 weeks by the subcutaneous route. No intervention was performed in the third control group (Group C), which consisted of 30 normal healthy volunteers. The improvement in Hb was assessed every 2 weeks, and the amplitude and latency of the P300 component of the ERPs were studied before initiating treatment and after 6 weeks of rhuEPO administration. There was a significant increase in Hb in both the study groups without any significant alteration in kidney functions. A significant reduction in P300 latency was noted in both the study groups after intervention. Similarly, the amplitude of P300 also increased in both study groups, but attained statistical significance for the dialysis group only. No significant changes were observed in the control group. Administration of EPO in patients of anemia with CKD resulted in a significant improvement in the electrophysiological markers of cognitive function in the form of increased amplitudes and decreased latencies of P300 in both predialysis and dialysis patients. [source] Correction of an anemia in patients with a terminal stage chronic renal insufficiency on haemodialysisHEMODIALYSIS INTERNATIONAL, Issue 1 2005R.Z. Ismagilov One of the basic symptoms of a terminal stage chronic renal insufficiency is anemia. From everything, used methods of correction of an anemia, it is considered the most effective application of preparations recombinant human erythropoietin (r-Hu EPO). Since 1994 in the Scientific Centre of Surgery begins application r-Hu EPO. Application r-Hu EPO in patients with a terminal stage chronic renal insufficiency in 90,95% of cases had a positive effect, but 5,10% of patients have intolerance to erythropoietin, that has induced to search of new effective methods of correction of anemia. During research were determined quantity erythrocytes, hemoglobin, reticulocyte in peripheral blood and acid-alkaline condition of blood. All hematology parameters were defined at the beginning of treatment, over 5 day and for 15 day of stimulation of a bone marrow. For 15 days after stimulation of a bone marrow by the laser there was an authentic increase of quantity erythrocyte, hemoglobin, hematocrit. The initial contents erythrocytes made 2.22 ± 0.1 10 × 12, hemoglobin 67.7 ± 3.2 g/l and hematocrit 18.2 ± 1.2%. During treatment by the laser parameters erythrocytes have increased up to 2.9 ± 0.8 10 × 12, hemoglobin up to 89.6 ± 2.9 g/l and hematocrit up to 28.2 ± 1.3%(P < 0,005). Hematology parameters in blood of control group authentically have not changed. [source] Long slow night hemodialysis and quality of lifeHEMODIALYSIS INTERNATIONAL, Issue 1 2005P. Hakkarainen Background:,Long slow hemodialysis (LS-HD) improves many biochemical parameters compared with conventional HD. However, its influences on quality of life are less well known. Aims:,The objective of this study was to examine the quality of life of patients on LS-HD performed overnight compared to the patients on standard hemodialysis. This extends the previous study, conducted in 2001, which examined the LS-HD patients, quality of life. Patients and methods:,We sent questionnaires to 12 LS-HD (overnight, treatment time 8 h × 3/wk) patients and 15 day HD (4.5 h × 3/wk) patients, all being treated using the limited care method. Data was collected using two different structured questionnaires. One was constructed for a previous study (2001) and the other one was a standardized set of questionnaires (RAND-36). Research material was collected from patient documents, such as the essential biochemical parameters, blood pressure, weight gain, and weekly EPO doses were recorded. Ten of the LS-HD patients (83%) and 13/15 (87%) of day HD patients returned the questionnaires. Three day hemodialysis patients returned empty questionnaires, which were disqualified. Results:,Based on the medical facts, the results showed that the patients of LS-HD felt better than the patients in another group. Patients on the LS-HD had higher Kt/V (2.623 vs. 1.577) and Hb (118 vs. 111) and lower Pi (1.36 vs. 1.63) and EPO dose (epoietin-beta 2667 ky/week vs. 5833 ky/week; darbepoetin 16 ky/week vs. 37 ky/week). However, their predialysis BP as well as the weight gain between treatments and salt and fluid balances caused problems furthermore. The experiences of the therapy of the LS-HD patients were more positive than of the control group: they felt their medical condition was better than of the patients on day HD. However we didn't observe significant differences in the replies showing physical or psychosocial conditions between the two groups. Conclusions:,The study suggests that when patients can themselves make the choice between treatment modalities, it improves the quality of life of the patients. Control of anemia is improved in LS-HD overnight patients with lower doses of EPO. The LS-HD gives the patients more freedom of diet. However, more attention must be paid to salt and fluid restriction. The LS-HD makes it possible for many patients to work normally. [source] Short Daily Dialysis (SDHD) Efficacy : Pilot Multicentric Study with Nine Patients from MadridHEMODIALYSIS INTERNATIONAL, Issue 1 2003G. Barril Interest in quotidian (daily) hemodialysis (HD) seems to be growing. Clinical data consistently showed improved quality of life, better control of blood pressure, less need for medications including erythropoietin (EPO) and better nutrition. We evaluate the SDHD efficacy in 9 patients in conventional HD (3 weekly sesions/4 hours), mean age 57,78 years range (33,75), 6 males and 3 females who needed increased dialysis efficiency by different medical indications: 5 cases with hypertensive miocardiopathy and severe LVH, 2 of them with EFLV 26% and 27%. 2 cases with ischemic cardiopathy symptoms, one of them with anger and restless dysnea with a non resvascularizable coronary lesion, and other with cardiac insufficiency episodes requiring hospitalization once a month. 1 patient with big body surface area and elevated phosphorus levels although without control, with conventional three times/week HD. 1 patient indication was made by 12 years on HD with multiple vascular accesses failed needing a Tessio cathéter being into infradialysis regimen for his malnutrition status. The schedule in all of them was 6 days per week sessions between 2.15 hrs till 3 hours depending of body surface area to obtain a weekly kt/v nearest to 4. HD session were realized in the Hospital (4 pts) or in satellite unit (5 pts) due to the characteristics of the patients. The time remaining in this schedule was between 5 months to 2 years and 9 months. All the patients showed clinical improvement, subjective and objective, since the first weeks of starting SDHD. Sleep symptoms were the first to improve. All patients showing good coping with this HD alternative. Blood pressure levels were controlled without need for antihypertensive drugs, although the dry weight increased significantly in all cases. Albumin serum levels increased as nutrition parameter, controlling also the osteodystrophy and phosphorus. In a patient the EFLV was normalized from 6 months (26%,50%) improving in other. Two patients could be included in Tx waiting list. Again, anemia improved and decreasing EPO was required. No vascular access (autologous AVF) malfunction was detected in relation to daily procedure. Conclusion: Our pilot experience shows a clinical and biochemical improvement in the patients and quality of life as well. Prospective studies to demonstrate the financial benefits of these modalities are needed. [source] Low dose erythropoietin-beta improves anemia and maintains ribavirin dose in chronic hepatitis C patients receiving combination therapy with ribavirin plus pegylated interferon Alfa-2bHEPATOLOGY RESEARCH, Issue 6 2009Kuo-Chih Tseng Aim:, Anemia during combination therapy with pegylated interferon alfa-2b plus ribavirin (RBV) for chronic hepatitis C virus (HCV) patients usually leads to RBV dose reduction or discontinuation. This study evaluated the effect of erythropoietin-beta (EPO-,) to maintain RBV dose and hemoglobin (Hb) level in chronic HCV patients treated with antiviral combination therapy. Methods:, Eighty-eight chronic HCV patients who developed anemia during therapy were enrolled into this retrospective study: 55 in the EPO-, group and 33 in the untreated group. The study endpoints were to assess the RBV maintenance and the changes in Hb. Results:, A higher percentage of patients with RBV maintenance was observed in the EPO-, group compared with the untreated group (nadir Hb level <10.5 g/dL; 70% vs. 38%, P = 0.020; nadir Hb < 10 g/dL; 62% vs. 27%, P = 0.046). The mean Hb change from week 12 to week 20 was higher in the EPO-, group when compared with the untreated group, especially for patients receiving a total EPO-, dose of more than 16 000 U (+0.70 g/dL vs. ,0.32 g/dL, P = 0.023) and of 10 000 U-14 000 U (+0.60 g/dL vs. ,0.32 g/dL, P = 0.023). Conclusions:, Low-dose EPO-, can maintain RBV dose and increase Hb levels in anemic chronic HCV patients receiving combination therapy. [source] Anaemia in heart failure: a common interaction with renal insufficiency called the cardio-renal anaemia syndromeINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 2 2008A. Palazzuoli Summary Background:, Although many studies have found a high prevalence of anaemia in patients with congestive heart failure (CHF), few have carefully examined the relationship between the CHF and the prevalence of anaemia and chronic renal insufficiency (CRI). Patients with advanced renal failure, significant anaemia, diffuse atherosclerosis, respiratory disease and more elderly patients have been systematically excluded from the great majority of the randomised clinical trials. Discussion:, Both anaemia and renal insufficiency are very common associated diseases associated with increased mortality, morbidity and rate of hospitalisation in CHF patients. Impaired renal function is associated with adverse outcomes because it represents a marker of coexistent disease and more diffuse atherosclerosis. In patients with CHF, progressive renal dysfunction leads to a decrease in erythropoietin (EPO) levels with reduced erythrocyte production from bone marrow. This may explain the common association between CHF, anaemia and CRI in clinical practice. The normalisation of haemoglobin concentration by EPO in patients with CHF and CRI results in improved exercise capacity by increasing oxygen delivery and improving cardiac function. Conclusion:, In this review, we describe the mechanisms linking anaemic status, CRI and CHF, the prognostic relevance of each disease, treatment implications, and potential benefit of EPO administration. [source] Property changes and cholesterol-lowering effects in evening primrose oil-enriched and cholesterol-reduced yogurtINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 1 2007SU-JEONG LEE The present study was carried out to investigate the changes in chemical and sensory properties and the cholesterol-lowering effect of evening primrose oil (EPO) addition to cholesterol-reduced yogurt. The rate of cholesterol removal reached 93.5% by ,-cyclodextrin in yogurt before EPO addition. pH, viscosity and microbial counts decreased with amounts of EPO added. The thiobarbituric acid value of cholesterol-reduced and EPO-enriched yogurt increased proportionally to length of storage period and amount of EPO addition, and it was significantly different between the EPO-enriched groups than in unenriched groups in all storage periods. The production of short-chain free fatty acids (FFA) increased with longer periods of storage. From 6 days' storage, the amounts of short-chain FFA in 6 and 10% EPO-enriched groups were significantly different from other groups. Most sensory scores of 2% EPO-enriched group were not significantly different from those of the control, whereas 6 and 10% EPO addition showed an adverse effect on sensory analysis. In blood analysis, the total cholesterol increase after 8 weeks' feeding was dramatically lowered to 39.2% in the 10% EPO-enriched group from 57.7% in the control. In addition, the concentration of blood triglyceride increased in the control, whereas it decreased in the 10% EPO-enriched group. The above results indicated that EPO addition resulted in a profound lowering effect in blood lipids, although it adversely affected some sensory properties. [source] The utility of immature reticulocyte fraction as an indicator of erythropoietic response to altitude training in elite cyclistsINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1p2 2010V. S. NADARAJAN Summary Altitude training is sometimes employed by elite endurance athletes to improve their sea level performance. This improvement results from the increased red cell mass consequent upon the boost in erythropoietin (EPO) level that occurs as a response to the relatively hypoxic environment at high altitudes. We measured serum EPO levels together with various red cell and reticulocyte parameters including immature reticulocyte fraction (IRF) in eight national track-endurance cyclists, resident at sea-level, prior to and upon return from an altitude of approximately 1905 m. Reticulocytes and soluble transferrin receptor (sTfR) were significantly increased with reduction in ferritin levels immediately on return from high altitude indicating increased erythropoietic activity. IRF in particular showed a significant peak immediately on return but decline to sub-baseline levels by day 9, and recovery to baseline by day 16. Our results indicate that IRF is a sensitive marker of erythropoietic status in athletes undergoing altitude training and subsequent loss of EPO stimuli on return to sea level. [source] A sample distribution programme for erythropoietinINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 4 2006J. T. MARSDEN Summary A survey was sent to laboratories participating in the United Kingdom External Quality Assessment Service (UKNEQAS) Haematinics Scheme about the measurement of serum erythropoietin (EPO). Six laboratories, from a total of 120 that returned the survey, were measuring serum EPO concentrations by commercially available immunoassays on site in the United Kingdom. The workload of the laboratories varied from up to 100 specimens per month to more than 100 specimens analysed per week. All laboratories included control material in the assays and none of the laboratories was participating in an external quality assessment scheme for serum EPO. Four laboratories agreed to take part in the first sample distribution programme, with five and six laboratories participating in distributions 2 and 3 respectively. The results from eight kits were compared from the three distributions over a 2-year period. The serum EPO concentrations for the methods showed some variation across the range of 2.9,200 U/l when the serum EPO concentrations for each method were compared with the whole method mean. The results from this scheme have identified a role for an external quality assessment scheme for serum EPO measurements. [source] Hydroxyurea therapy increases plasma erythropoietin in patients with essential thrombocythaemia or polycythaemia veraINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 4 2006P. JOHANSSON Summary The determination of serum/plasma erythropoietin (EPO) concentration has gained widespread use in the diagnosis of polycythaemia vera (PV). A reduced EPO concentration in a newly diagnosed essential thrombocythaemia (ET) seems to be a risk factor for thromboembolic events. In this study plasma EPO concentration was determined before and after initiated hydroxyurea (HU) therapy, 14 patients with PV or ET were included. After 1 month on HU therapy 11 of 14 patients had increased their EPO concentration compared with prior to medication. The plasma EPO was increased in all, except one patient, after 4 months HU therapy. If EPO is incorporated in the diagnostic or prognostic procedures it should be determined before myelosuppressive therapy is initiated. [source] Erythropoietin-producing renal cell carcinoma in chronic hemodialysis patients: A report of two casesINTERNATIONAL JOURNAL OF UROLOGY, Issue 1 2003SHINICHI SAKAMOTO Abstract Erythropoietin (EPO)-producing renal cell carcinomas in two hemodialysis patients are reported. Despite deteriorated kidney function, these patients did not manifest anemia at diagnosis and their elevated serum EPO levels rapidly returned to within the normal range after nephrectomy. Immunohistochemical staining of the resected specimens showed production of erythropoietin in the tumor cells in one case and in the lining cells of the cyst wall in the other case. Renal cell carcinoma could cause an increase of blood hematocrit level in dialysis patients. [source] Cloning and molecular dissection of the 8.8 kb pig uroplakin II promoter using transgenic mice and RT4 cellsJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2006Deug-Nam Kwon Abstract Uroplakin II (UPII) gene expression is highly tissue and cell specific, with mRNA present in the suprabasal cell layers of the bladder and urethra. Previous reports described the mouse UPII (mUPII) promoter as primarily urothelium selective. However, ectopic expression of a transgene under the 3.6 kb mUPII promoter was also detected in brain, kidney, and testis in some transgenic mouse lines. Here, we have cloned an 8.8 kb pig UPII (pUPII) promoter region and investigated which cells within the bladder and urethra express a transgene consisting of the pUPII promoter fused to human erythropoietin (hEPO) or a luciferase gene. pUPII-luciferase expression vectors with various deletions of the promoter region were introduced into mouse fibroblast (NIH3T3), Chinese hamster ovary (CHO), and human bladder transitional carcinoma (RT4). A 2.1 kb pUPII promoter fragment displayed high levels of luciferase activity in transiently transfected RT4 cells, whereas the 8.8 kb pUPII promoter region displayed only low levels of activity. The pUPII-hEPO expression vector was injected into the pronucleus of zygotes to make transgenic mice. To elucidate the in vivo molecular mechanisms controlling the tissue- and cell-specific expression of the pUPII promoter gene, transgenic mice containing 2.1 and 8.8 kb pUPII promoter fragments linked to the genomic hEPO gene were generated. An erythropoietin (EPO) assay showed that all nine transgenic lines carrying the 8.8 kb construct expressed recombinant human erythropoietin (rhEPO) only in their urethra and bladder, whereas two transgenic lines carrying the 2.1 kb pUPII promoter displayed hEPO expression in several organs including bladder, kidney, spleen, heart, and brain. These studies demonstrate that the 2.1 kb promoter contains the DNA elements necessary for high levels of expression, but lacks critical sequences necessary for tissue-specific expression. We compared binding sites in the 2.1 and 8.8 kb promoter sequences and found five peroxisome proliferator responsive elements (PPREs) in the 8.8 kb promoter. Our data demonstrated that proliferator-activated receptor (PPAR)-, activator treatment in RT4 cells induced the elevated expression of hEPO mRNA under the control of the 8.8 kb pUPII promoter, but not the 2.1 kb promoter. Collectively, our data suggested that all the major trans-regulatory elements required for bladder- and urethra-specific transcription are located in the 8.8 kb upstream region and that it may enhance tissue-specific protein production and be of interest to clinicians who are searching for therapeutic modalities with high efficacy and low toxicity. J. Cell. Biochem. 99: 462,477, 2006. © 2006 Wiley-Liss, Inc. [source] Expression of signal transduction proteins during the differentiation of primary human erythroblastsJOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2005Viviana di Giacomo The high number (>108,10) of primary human pro-erythroblasts (CD36high/CD235alow) obtainable in HEMA culture (Migliaccio et al., 2002) is exploited here to analyse the expression of proteins implicated in erythropoietin (EPO)-signalling (STATs, PI-3K, and PLCs) during the process of erythroid maturation. Human pro-erythroblasts progressed in 4 days of culture with EPO into basophilic- (CD36high/CD235amedium, 24 h), polychromatic-(CD36high/CD235ahigh, 48 h), and, finally, orthochromatic-(CD36low/CD235ahigh, 72,96 h) erythroblasts. During this maturation, STAT-1 was expressed up to the orthochromatic stage, expression of STAT-5, as well as of its target proteins BclxL and IRF1, remained constant up to 48 h (polychromatic-erythroblasts) but decreased by 96 h (orthochromatic-erythroblasts), while that of STAT-3 decreased constantly from 24 h on and became undetectable by 96 h. Expression of PI-3K rapidly decreased with differentiation since only 50% of original protein levels were detected by 48 h. On the other hand, among the members of PLC families investigated, PLC ,4 was not expressed, PLC ,2, ,1, and ,2 were expressed at constant levels throughout the maturation process, while expression of PLC ,3 and of PLC ,1 decreased, as PI-3K, by 24 h and that of PLC ,1 was induced by 6 h and became undetectable by 24 h. In conclusion, these data depict the dynamic signalling scenario associated with the maturation of erythroid cells and provide the first indication that members of PLC families (PLC ,1, ,3, and ,1) might e involved in the control of erythroid differentiation in humans. © 2004 Wiley-Liss, Inc. [source] Erythropoietin-mediated tissue protection: reducing collateral damage from the primary injury responseJOURNAL OF INTERNAL MEDICINE, Issue 5 2008M. Brines Abstract. In its classic hormonal role, erythropoietin (EPO) is produced by the kidney and regulates the number of erythrocytes within the circulation to provide adequate tissue oxygenation. EPO also mediates other effects directed towards optimizing oxygen delivery to tissues, e.g. modulating regional blood flow and reducing blood loss by promoting thrombosis within damaged vessels. Over the past 15 years, many unexpected nonhaematopoietic functions of EPO have been identified. In these more recently appreciated nonhormonal roles, locally-produced EPO signals through a different receptor isoform and is a major molecular component of the injury response, in which it counteracts the effects of pro-inflammatory cytokines. Acutely, EPO prevents programmed cell death and reduces the development of secondary, pro-inflammatory cytokine-induced injury. Within a longer time frame, EPO provides trophic support to enable regeneration and healing. As the region immediately surrounding damage is typically relatively deficient in endogenous EPO, administration of recombinant EPO can provide increased tissue protection. However, effective use of EPO as therapy for tissue injury requires higher doses than for haematopoiesis, potentially triggering serious adverse effects. The identification of a tissue-protective receptor isoform has facilitated the engineering of nonhaematopoietic, tissue-protective EPO derivatives, e.g. carbamyl EPO, that avoid these complications. Recently, regions within the EPO molecule mediating tissue protection have been identified and this has enabled the development of potent tissue-protective peptides, including some mimicking EPO's tertiary structure but unrelated in primary sequence. [source] Intrinsic and extrinsic erythropoietin enhances neuroprotection against ischemia and reperfusion injury in vitroJOURNAL OF NEUROCHEMISTRY, Issue 4 2006Ruiqin Liu Abstract This study was designed to investigate the neuroprotective effect of intrinsic and extrinsic erythropoietin (EPO) against hypoxia/ischemia, and determine the optimal time-window with respect to the EPO-induced neuroprotection. Experiments were conducted using primary mixed neuronal/astrocytic cultures and neuron-rich cultures. Hypoxia (2%) induces hypoxia-inducible factor-1, (HIF-1,) activity followed by strong EPO expression in mixed cultures and weak expression in neuron-rich cultures as documented by both western blot and RT,PCR. Immunoreactive EPO was strongly detected in astrocytes, whereas EPOR was only detected in neurons. Neurons were significantly damaged in neuron-rich cultures but were distinctly rescued in mixed cultures. Application of recombinant human EPO (rhEPO) (0.1 U/mL) within 6 h before or after hypoxia significantly increased neuronal survival compared with no rhEPO treatment. Application of rhEPO after onset of reoxygenation achieved the maximal neuronal protection against ischemia/reperfusion injury (6 h hypoxia followed 24 h reoxygenation). Our results indicate that HIF-1, induces EPO gene released by astrocytes and acts as an essential mediator of neuroprotection, prove the protective role of intrinsic astrocytic-neuronal signaling pathway in hypoxic/ischemic injury and demonstrate an optimal therapeutic time-window of extrinsic rhEPO in ischemia/reperfusion injury in vitro. The results point to the potential beneficial effects of HIF-1, and EPO for the possible treatment of stroke. [source] Quantitative EEG in Patients With Alcohol-Related SeizuresALCOHOLISM, Issue 10 2010Trond Sand Background:, To investigate whether quantitative electroencephalography (QEEG) recorded within a few days after a generalized seizure can improve the discrimination between alcohol-related seizures (ARSs), seizures in epilepsy and other seizures. In addition, we wanted to evaluate the influence of various external factors on QEEG, e.g., drug use, time from seizure occurrence, and alcohol intake. Methods:, An ARS was defined by (i) scores ,8 in the Alcohol Use Disorders Identification Test (AUDIT) and (ii) no history of epilepsy. Twenty-two ARS patients, 21 epileptic patients with seizures (ES), 30 AUDIT-negative patients with seizures (OS), and 37 well-controlled epileptic outpatients (EPO) were included. EEG from 79 sciatica patients (SC) served as an additional control group. EEG was recorded in relaxed wakefulness with eyes closed. Spectral analysis of ongoing resting EEG activity was performed. For the main analysis, spectral band amplitudes were averaged across 14 electrodes. Results:, Major quantitative EEG abnormalities were mainly seen in the ES group. AUDIT score correlated negatively with QEEG band amplitudes in patients with seizures unrelated to alcohol, but not in the ARS group. Recent alcohol intake correlated negatively with delta and theta amplitude. We could not confirm that beta activity is increased in ARS subjects. Conclusions:, A QEEG with slightly reduced alpha amplitude supports a clinical diagnosis of ARS. An abnormally slow QEEG profile and asymmetry in the temporal regions indicates ES. QEEG predicted the clinical diagnosis better than standard EEG. [source] Intraepidermal innervation and tail nerve conduction velocity in neurotoxicity models: results of a correlation study in normal and pathological conditionsJOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 2 2004M Borgna Animal models of human diseases affecting the peripheral nervous system are widely used to assess the pathogenesis of neurotoxicity and to compare the effect of new agents. Several behavioural, pathological and neurophysiological methods have been used, and each has advantages and disadvantages. A major goal in the study of neurotoxicity would be to assess the damage in the same way in animal models and in humans. In this study we correlated the neurophysiological results obtained in normal rats and in rats treated with cisplatin 2 mg/kg q3d × 8 with the density of intraepidermal fibers (IEF) obtained in skin biopsy specimens. The aim was to investigate the possible role of a minimally invasive procedure such as skin biopsy as an alternative method to assess the peripheral neurotoxicity of antineoplastic drugs. The nerve conduction velocity (NCV) in the tail nerve was assessed in thirty-six young adult female Wistar rats which were left untreated, or treated with erythropoietin (EPO), cisplatin (CDDP) or EPO + CDDP. CDDP and CDDP + EPO-treated rats had a significantly reduced NCV vs. age-matched untreated rats. At sacrifice, skin specimens were obtained. The density of IEF was calculated by 2 independent blinded examiners and the correlation existing between NCV and IEF was highly significant (r = 0.670, p < 0.001). This preliminary result suggests that IEF should be evaluated in other animal models and might represent a useful tool to study peripheral neurotoxicity also in humans. [source] Abstracts of the 8th Meeting of the Italian Peripheral Nerve Study Group: 21JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2003R Bianchi Erythropoietin (EPO) has neurotrophic and neuroprotective effects and its efficacy and safety has been demonstrated in patients with ischemic stroke. We investigated its efficacy in preventing and reversing established nerve disorders in streptozotocin (STZ) diabetes. After STZ injection (60 mg/kg/ip), EPO (5000 units/kg b.w. i.p. three times a week) was started in a group of rats and continued for five weeks (prevention schedule). In another group of diabetic rats, EPO was started six weeks after STZ, continued for five weeks (therapeutic schedule). Groups of non-diabetic control rats were similarly treated. Antidromic nerve conduction velocity (NCV) in the tail was assessed at five weeks for all groups and at 11 weeks for the therapeutic schedule. Compared to non-diabetic rats, NCV was 21% lower (P < 0.001) at five weeks in the STZ group, EPO partially prevented this decrease (14% lower than with non-diabetic controls), with a significant difference from the untreated-diabetic group (P < 0.01). After six weeks of uncontrolled diabetes, at the beginning of therapeutic EPO, NCV was reduced by 23% and after 11 weeks by 40%, EPO efficacy was confirmed. Thermal (hot plate method) and mechanical (Randall-Selitto method) nociceptive thresholds were monitored weekly throughout the study. In addition, in all groups, the density of intra-epidermal nerve fibers, which reflects possible degeneration of somatic unmyelinated fibers, was assessed in the hindpaw using protein-gene-product 9.5 immunostaining. Rats developed mechanical hyperalgesia within two weeks after STZ injection. Both the prevention and therapeutic schedules of EPO reduced diabetic hyperalgesia after two weeks of treatment, reaching statistical significance at fur, and five weeks of treatment, with no such effect in non-diabetic controls. Hindpaw thermal response latencies were significantly (P < 0.001) increased in untreated diabetic rats compared with untreated controls. EPO had no effect on these latencies in control rats but partially prevented the increase in diabetic rats, so the values were still different from controls, but significantly different from untreated diabetics at four and five weeks in both the prevention and therapeutic studies (P < 0.05). These observations extend the therapeutic utility of EPO and highlight its potential for treating established diabetic neuropathies. [source] Serum eosinophil granule proteins predict asthma risk in allergic rhinitisALLERGY, Issue 5 2009L. P. Nielsen Background:, Allergic rhinitis is a common disease, in which some patients will deteriorate or develop asthma. It is important to characterize these patients, thereby offering the possibility for prevention. This study evaluated eosinophil parameters as potential indicators of deteriorating allergic airway disease. Methods:, The subjects of the study included all patients who suffered seasonal allergic rhinitis and had participated in a study 6 years earlier, in which blood eosinophils, serum eosinophil cationic protein (ECP) serum eosinophil peroxidase (EPO), nasal lavage ECP and nasal lavage EPO levels were measured. Patients in the present study were interviewed on occurrence of rhinitis symptoms during the last season, rhinitis outside season, asthma-like symptoms and asthma diagnosis, and were skin-prick tested for common aeroallergens. Eosinophil parameters from the study 6 years earlier were then tested for the ability to predict occurrence of new allergies, worsening of rhinitis and occurrence of asthma. Results:, Forty-four patients participated in the study. In four patients seasonal rhinitis symptoms had deteriorated, 10 had experienced perennial rhinitis symptoms, 14 reported asthma-like symptoms and seven had been diagnosed with asthma. Thirteen had developed additional sensitization. Patients developing asthma-like symptoms compared with patients with no such symptoms had significantly higher serum ECP (16.7 ,g/l vs 8.2 ,g/l; P , 0.01) and serum EPO (17.9 ,g/l vs 8.8 ,g/l; P , 0.05). Results were similar, considering patients diagnosed with asthma. Blood eosinophils and nasal lavage parameters were not related to development of asthma and asthma-like symptoms. No eosinophil parameter was related to deterioration of rhinitis or additional sensitization. Conclusion:, Serum ECP and EPO in patients with seasonal rhinitis demonstrated a high predictive ability for later development of asthma. [source] Novel renoprotective actions of erythropoietin: New uses for an old hormone (Review Article)NEPHROLOGY, Issue 4 2006DAVID W JOHNSON SUMMARY: Erythropoietin (EPO) has been used widely for the treatment of anaemia associated with chronic kidney disease and cancer chemotherapy for nearly 20 years. More recently, EPO has been found to interact with its receptor (EPO-R) expressed in a large variety of non-haematopoietic tissues to induce a range of cytoprotective cellular responses, including mitogenesis, angiogenesis, inhibition of apoptosis and promotion of vascular repair through mobilization of endothelial progenitor cells from the bone marrow. Administration of EPO or its analogue, darbepoetin, promotes impressive renoprotection in experimental ischaemic and toxic acute renal failure, as evidenced by suppressed tubular epithelial apoptosis, enhanced tubular epithelial proliferation and hastened functional recovery. This effect is still apparent when administration is delayed up to 6 h after the onset of injury and can be dissociated from its haematological effects. Based on these highly encouraging results, at least one large randomized controlled trial of EPO therapy in ischaemic acute renal failure is currently underway. Preliminary experimental and clinical evidence also indicates that EPO may be renoprotective in chronic kidney disease. The purpose of the present article is to review the renoprotective benefits of different protocols of EPO therapy in the settings of acute and chronic kidney failure and the potential mechanisms underpinning these renoprotective actions. Gaining further insight into the pleiotropic actions of EPO will hopefully eventuate in much-needed, novel therapeutic strategies for patients with kidney disease. [source] Anemia in children after transplantation: etiology and the effect of immunosuppressive therapy on erythropoiesisPEDIATRIC TRANSPLANTATION, Issue 4 2003Amira Al-Uzri Abstract: Anemia in children after renal transplantation is more common than previously appreciated. Multiple factors appear to play roles in the development of post-transplant anemia, the most common of which is absolute and/or functional iron deficiency anemia. Most experts recommend that iron limited anemias in transplant patients should be diagnosed using the same criteria as for chronic renal failure patients. Serum erythropoietin (EPO) levels are expected to normalize after a successful renal transplantation with a normal kidney function, yet both EPO deficiency and resistance have been reported. While no large controlled trials comparing the effect of different immunosuppressive agents on erythropoiesis after transplantation have been performed, generalized bone marrow suppression attributable to azathioprine (AZA), mycophenolate mofetil (MMF), tacrolimus, antithymocyte preparations has been reported. Pure red cell aplasia (PRCA) occurs rarely after transplantation and is characterized by the selective suppression of erythroid cells in the bone marrow. PRCA has been reported with the use of AZA, MMF, tacrolimus, angiotensin converting enzyme inhibitors (ACEI), but not with cyclosporine (CSA) use. Post-transplant hemolytic uremic syndrome has been reported with orthoclone anti T-cell antibody (OKT3), CSA and tacrolimus therapy. Viral infections including cytomegalovirus, Epstein,Barr virus and human parvovirus B19 have been reported to cause generalized marrow suppression. Management of severe anemia associated with immunosuppressive drugs generally requires lowering the dose, drug substitution or, when possible, discontinuation of the drug. Because this topic has been incompletely studied, our recommendation as to the best immunosuppressive protocol after renal transplantation remains largely dependent on the clinical response of the individual patient. [source] Nucleated red blood cell counts and erythropoietin levels in high-risk neonatesPEDIATRICS INTERNATIONAL, Issue 6 2002Ülfet Vatansever Abstract Background: The presence of increased numbers of nucleated red blood cells (NRBC) and increased levels of erythropoietin (EPO) in the circulation of neonates has been associated with states of relative hypoxia. The aim of this study is to assess the pattern of NRBC counts and EPO levels in a group of high-risk neonates under stress conditions and determine the short-term outcome for these babies by using these parameters. Methods: There were 69 high-risk neonates; 14 intrauterine growth retarded (IUGR), 25 preterm infants, 18 term infants with asphyxia and 12 infants of diabetic mothers. Control groups included healthy, term infants delivered either vaginally (n = 18) or with cesarean section (n = 19). Three blood samples were obtained from each infant within 12 h (initial), 3 days and 7 days after birth to measure NRBC counts and EPO levels. Neonatal and short-term outcomes at 3 and 6 months of age were determined. Results: There was no significant difference among the groups with regard to the initial serum EPO concentrations. The initial NRBC counts were significantly lower in the control groups compared with the study groups (P = 0.002). While there was no significant difference between patients with good and poor outcome in terms of EPO concentrations of initial samples, a significant difference existed in terms of NRBC counts (P = 0.038). Conclusions: Both serum EPO level and NRBC count provide limited clinical benefit in the detection of pathological conditions of the neonatal period, but NRBC count determination seems to be especially helpful in predicting short-term neurodevelopmental outcome. [source] | |||||||||||||||||||||||||||||||||||||||||||