ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 2020-2022
  • 2010-2014  (17)
  • 2013  (17)
Collection
Years
  • 2020-2022
  • 2010-2014  (17)
Year
  • 1
    Publication Date: 2013-11-01
    Print ISSN: 0022-3115
    Electronic ISSN: 1873-4820
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Physics
    Published by Elsevier
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2013-11-15
    Description: Background Cardiac iron removal is relatively slow and patients with cardiac siderosis can take years to normalize cardiac T2* to 〉20 ms. Prospective comparison of iron chelators are mostly limited to studies of 1-yr duration. CORDELIA is a large randomized trial comparing deferasirox (DFX) with deferoxamine (DFO) in patients with β-thalassemia major (TM), which demonstrated the non-inferiority of DFX vs DFO for cardiac iron removal at 1 yr, with a trend for superiority of DFX (P=0.057). This 1-yr extension was planned to collect additional data on efficacy and safety of DFX and DFO in patients with cardiac siderosis when treated for up to 2 yr. Methods Study design has been reported previously (Pennell Blood 2012; abst 2124). Patients enrolled had cardiovascular magnetic resonance-measured cardiac T2* 6–20 ms, left ventricular ejection fraction (LVEF) ≥56%, and R2-magnetic resonance imaging liver iron concentration (LIC) ≥3 mg Fe/g dw. Patients completing 1 yr were eligible to continue on DFX or DFO as assigned, or to switch treatment on entering the extension if judged by the investigator to be of therapeutic benefit. Target doses were an intensified DFO regimen of 50–60 mg/kg/d sc for 8–12 h, 5–7 d/wk, or DFX at 40 mg/kg/d. Efficacy is reported for changes from core baseline (BL). Safety was monitored continuously. Results for patients continuing with DFX or DFO are reported here. Results In total, 160/197 patients completed 1 yr; 74 patients continued into the extension on DFX (mean age 20.1 ± 6.9 yr; 59.5% male) and 29 patients on DFO (17.0 ± 5.4 yr; 58.6%). At core BL, 29.7% DFX patients had cardiac T2* 33% from BL and 〉 upper limit of normal (ULN) at 2 consecutive values occurred in 2.7% of DFX and 3.4% of DFO patients. Frequency of ALT elevations 〉5 x ULN and 2 x BL were comparable between groups. Discussion Cardiac T2* increased substantially during 2-yr treatment with DFX or DFO. Improvement with DFX was comparable with DFO, although DFO patient numbers were low. The magnitude of cardiac T2* improvement with DFX was consistent with previous long-term studies (Pennell Blood 2010). Mean LVEF was stable and remained within normal limits in both groups. LIC continued to decrease from very high BL levels with DFX and DFO. The reduction in CIC in the extension was similar or possibly greater than in the core, which might relate to the falling LIC. Long-term safety profiles of DFX and DFO were consistent with previous reports. Disclosures: Pennell: Shire: Consultancy, Honoraria; ApoPharma: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding. Porter:Celgene: Consultancy; Shire: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Research Funding. Piga:Novartis: Membership on an entity’s Board of Directors or advisory committees, Research Funding. Wegener:Novartis: Employment. Habr:Novartis: Employment. Shen:Novartis: Employment. Aydinok:Shire: Membership on an entity’s Board of Directors or advisory committees, Research Funding; Novartis: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Research Funding, Speakers Bureau.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2013-11-15
    Description: Background Transfusion-dependent patients with severe cardiac siderosis often require intensive iron chelation therapy for a limited time to facilitate rapid removal of iron from the heart, allowing patients to move from a high-risk (cardiac T2*
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2013-11-15
    Description: Introduction Complications of transfusional iron overload vary with the underlying hematologic condition and may be affected by inherent differences in non-transferrin bound iron (NTBI) generation between these conditions. We have previously reported high NTBI levels in Diamond Blackfan anemia (DBA) relative to sickle cell (SCD), despite lower serum ferritin and LIC associated with very low sTfR levels in DBA. This suggested that low transferrin iron utilization in DBA relative to SCD and thalassemia major (TM) accounted for high NTBI levels. It is known that pro-inflammatory cytokine IL6 will increase hepcidin synthesis thereby decreasing ferroportin expression on macrophages but it is not known whether high levels of inflammatory cytokines can overcome or limit the effects of iron overload in raising NTBI and transferrin saturation. Here we have examined additional factors that may affect NTBI levels in different forms of inherited anemias. The relationship of inflammatory markers, the hepcidin/ferritin ratio and monocyte ferroportin in these conditions to NTBI levels have been examined. The possible effect of vitamin C or vitamin D deficiency on NTBI has also been examined. Methods 15 iron-overloaded patients (5 from each group of TM, SCD, and DBA) with ferritin 〉 1500 g/dl or LIC 〉 7 mg/g dry wt, age 16, age 0 to 9 at initiation of transfusion and 10 to 20 years of transfusion exposure were enrolled from 3 sites in the US and Europe. 5 non-transfused healthy controls were also enrolled. Fasting, early morning blood samples (including WBC isolation) were obtained one day prior to transfusion. Chelation was held for 72 hours prior to each sample and samples taken pre-transfusion. Measurement of hepcidin, sTfR, GDF-15, transferrin saturation, NTBI and LPI was as described elsewhere. Inflammatory cytokine IL6 and IL10 were measured by multiplex bead fluorimetry. Ferroportin expression in circulating monocytes, a potential marker of its expression in resident macrophages of spleen, liver and bone marrow was measured by western blotting. Results Results shown in Table 1 are most notable for the following findings: in DBA, the inflammatory markers IL6 and IL10 are high as in SCD or TM. Furthermore plasma hepcidin levels and hepcidin/ferritin ratios are higher in DBA, than in SCD or TM. Despite these high values of hepcidin, IL6 and IL10, monocyte ferroportin levels and NTBI remain high in DBA. This suggests that chronically high levels of circulating hepcidin do not decrease NTBI in patients with low transferrin iron utilization (as in DBA) and that this latter effect combined with iron overload is the more powerful determinant in raising NTBI levels. If the circulating monocytes are a true reflection of resident tissue macrophages that phagocytize red cells, this would suggest that high hepcidin levels are insufficient to suppress ferroportin expression in the presence of severe iron overload. TGFb was most raised in SCD whereas TNFα, were similar in SCD, Thal and DBA. In SCD ferroportin levels on circulating monocytes were lower than DBA and Thal as well as being lower than control which could contribute to low transferrin saturation and low NTBI levels. Vitamin C levels were also lowest and this could contribute to iron retention within macrophages and hence the low NTBI levels observed in SCD. Conclusions Taken with our previous findings (ASH abstract 2012), our results are consistent with NTBI and Tf saturation being determined by an interaction of opposing effects, which vary depending on the underlying cause of anemia. NTBI and Tf saturation are increased by (a) iron overload, (b) low erythropoiesis though low utilization of transferrin iron. The findings in this study extension suggest that vitamin C deficiency in SCD could be a contributing factor to low NTBI and this requires further investigation. However the presence of a raised inflammatory cytokine and raised hepcidin appears to be insufficient to abrogate the combined effects of low utilization of transferrin iron and iron overload on raising NTBI in DBA. Disclosures: Porter: Novartis: Consultancy, Research Funding; Celgene: Consultancy; Shire: Consultancy. Walter:Novartis: Research Funding. Harmatz:Novartis: Research Funding; Shire: Consultancy, Honoraria, Research Funding, travel, travel Other. Vichinsky:Novartis: Honoraria, Research Funding.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2013-11-15
    Description: Background Patients with myocardial iron overload require effective cardiac iron removal to minimize the risk of cardiac complications. The 3 year EPIC cardiac sub-study showed that the oral iron chelator, deferasirox (DFX), effectively reduced cardiac iron overload. Previous reports demonstrate that cardiac iron removal is slow and suggest that liver iron concentration (LIC) may affect cardiac iron removal rate by chelators (Pennell et al., 2012; Blood). The objective of these analyses was to evaluate the impact of the severity of the liver iron overload on the change in myocardial T2* (mT2*) for patients receiving up to 3 years of DFX treatment in the EPIC sub-study. Methods Inclusion and exclusion criteria have been described previously (Pennell et al., 2012; Haematologica). Patients were categorized into LIC ≤15 and 〉15 mg Fe/g dry weight (hereafter mg/g) at baseline (BL) and by LIC 15 mg/g at 12, 24, and 36 months to assess the impact of BL LIC and changes in LIC overtime on mT2*, respectively. During study, LIC and mT2* were measured every 6 months. Efficacy was assessed in per-protocol population that entered third year extension. Here, mT2* is presented as the geometric mean (Gmean) ± coefficient of variation (CV) unless otherwise specified. Statistical significance was established at α-level of 0.05 using a 2-sided paired t-test for within group comparisons and ANOVA for multiple group comparisons. All p-values were of exploratory nature for this post-hoc analysis. Results Of the 71 patients, who continued into study year 3, 68 patients considered evaluable were included in this analysis (per protocol population); 59 patients had LIC values available at end of study (EOS). Mean age was 20.5 ±7.35 years and 61.8 % of patients were female. Mean actual dose of DFX (mg/kg/day) was 32.1 ±5.5 and 35.1 ±4.9 in patients with BL LIC ≤15 and 〉15 mg/g, respectively. At EOS, mean actual doses were 32.9 ±5.4 (LIC 15 mg/g). Overall, patients had high BL LIC (Mean, 29.0 ±10.0 mg/g); 61 patients had LIC 〉15 (30.8 ±8.8) mg/g, only 7 patients had LIC ≤15 (12.7 ±1.1) mg/g, and no patients had LIC 15 mg/g achieved EOS LIC 15 mg/g (BL mT2*, 12.7 ±4.7 ms), mT2* increased by 52% (Mean abs. change, 7.5 ±4.1 ms, p=0.0016) and 46% (7.3 ±7.3 ms, p15 mg/g, (20.1 ±10.6 ms) displaying a lag of nearly 12 months. The relation between post-BL LIC on mT2* response at 12, 24 and 36 months is shown in the figure. At 12 months, there was no significant difference in mT2* that had occurred in patients with LIC 15 mg/g (13% increase; 1.9 ±3.2 ms). However, at 24 months, there was a statistically significant difference amongst the 3 subgroups in percent increase in the mT2* that had occurred; patients with LIC 15 mg/g had 54% (Mean abs. change, 8.3 ±7.3 ms), 33% (5.2 ±5.2 ms) and 10% (2.1 ±4.3 ms) increase (p
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2013-11-15
    Description: Introduction The thalassemias are inherited anemias sometimes characterized by severe transfusion dependence that can lead to extra-hepatic cardiac iron overload, causing cardiomyopathy. Despite improved chelation therapies, patients with transfusion-dependent thalassemia still endure cardiomyopathy and chronic inflammation. The innate immune system provides the first line of defense against infection and specificity depends on pattern recognition receptors (PRRs) specific to microbial pathogens. One class of PRR called the toll-like receptors (TLRs) interacts with CD14 on innate immune cells transducing the signal for bacterial lipopolysaccharide. Another cell surface protein that is not a PRR, but aids phagocytosis and is important in granulocytes function and chemotaxis is the adhesive polysaccharide antigen, CD15. The role that excess iron plays in determining expression level of these innate immune proteins is unknown. Thus, the goal in these studies is to investigate the relationship of cardiac iron overload and its chelation to innate immune cell expression of TLR4 and CD15 in patients with transfusion-dependent thalassemia. Patients and Methods Eighteen patients with transfusion dependent thalassemia (11 – 29 years old) (participating in the Novartis sponsored CICL670AUS24T) were enrolled in a substudy investigating innate immunology (Novartis sponsored CICL670AUS42T). Patients were investigated at baseline, then after 6 months and one year of combined chelation therapy with deferasirox and deferoxamine. Fasting blood samples were obtained after a 72 hr washout with no chelators. Fourteen healthy controls (10 - 35 yrs old) were also enrolled. Changes in LIC (ferritometer), cardiac function (MRI) and myocardial iron (MRI T2*) were monitored. Peripheral blood mononuclear cells (PBMCs) and granulocytes were isolated from blood samples using density gradients. Monocytes and granulocytes were further purified using antibody-linked magnetic microbeads. Highly enriched populations of CD14+ monocytes and CD15+ granulocytes were verified by flow cytometry. The expression level of CD15 and TLR4 was determined. Results Previously we found that transfusion-dependent thalassemia patients had 37% higher TLR4+ neutrophils than control patients and a smaller percentage of CD15+ neutrophils. We have also observed a decrease in TLR4 expression during the course of combined chelation therapy on neutrophils but not monocytes, indicating that TLR4 is differentially modulated on neutrophils compared to monocytes. Now we find that these flow cytometry parameters show significant relationships to markers of iron burden. The percentage of TLR4+ monocytes was related to liver iron concentration (r=- 0.49, p = 0.039), ferritin concentration (r=-0.47, p = 0.049), serum iron level (r=0.61, p = 0.008), and total iron binding capacity (TIBC; r=0.51, p = 0.021), while the percentage of CD15 positive neutrophils predicted myocardial iron, as measured by MRI T2* (r= 0.69, p
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2013-04-01
    Print ISSN: 1540-9295
    Electronic ISSN: 1540-9309
    Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering
    Published by Wiley on behalf of Ecological Society of America.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2013-11-15
    Description: Objectives Beta-Thalassaemia-Major is a life-long genetic haemoglobin disorder where patients require intensive regimens, including frequent blood transfusions and daily chelation therapy. Despite the introduction of oral chelators, non-adherence continues to be prevalent. Understanding psychosocial correlates of chelation adherence is important when considering potential interventions to improve adherence as they may be potentially modifiable. Previous studies of the relationships between psychosocial factors and chelation adherence have neither been theory driven nor assessed theoretically important variables such as self-efficacy and outcome expectancies. In addition, there has been little investigation of situational determinants of adherence (cognitive, behavioural or affective). This study, informed by the Health Action Process Approach, investigated within-participant correlates of oral chelation adherence on a daily (episodic) basis. Design The study used a within-participant cross sectional design. Thirty seven adult participants with Beta-Thalassaemia Major were recruited from clinics at two hospitals, of which 31 were able to identify an adherent and non-adherent episode within the last two months. Sampling was systematic. Main outcome measures A structured interview was developed to assess cognitive, behavioural and affective situational variables related to recent adherent and non-adherent episodes. The main cognitive variables (situational self-efficacy and outcome expectancies) were derived from The Health Action Process Approach (HAPA). Behavioural situation variables included substance use, day of the week, activity, location, access to medication, reminder cues and social context. Affective situational variables were mood and bodily pain. Results Positive outcome expectancies and higher self-efficacy together significantly predicted adherent episodes (p
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2013-11-15
    Description: Introduction Monotherapy with clinically available chelators, namely deferoxaime (DFO), deferasirox (DFX) or deferiprone (DFP) is effective but often slow and suboptimal. Combinations of DFO with DFP have been used clinically to enhance cellular iron mobilization but the conditions under which this occurs have not been studied systematically. With the emergence of DFX, the possibility exists to combine this with either DFO or DFP to enhance chelation. We have developed a system to study the optimal concentrations and times of exposure to these chelators, alone or in combination for maximising cellular iron removal. Isobol modeling has been used to determine whether interaction is additive or synergistic. The demonstration of synergy would imply the primary chelator acting as a ‘sink’ for iron chelated and donated to this sink by low concentrations of a secondary ‘shuttle’ chelator as shown in plasma (Evans et al. TransL. Res, 2010). Methods Human hepatocellular carcinoma (HuH-7) cells were chosen as hepatocytes are the major cell of iron storage in iron overload. Iron concentration was determined using the ferRozine (Riemer et al. Anal Biochem. 2004). A threefold increase of intracellular iron compared to control was obtained by serially treating cells with 10% FBS RPMI media. The cells were then exposed to iron chelator then lysed and intracellular iron concentration determined via the ferrozine assay, normalized against protein content. Cell viability was assessed using 0.4% Trypan blue as well as Acridine Orange /Propidium Iodide and was consistently 〉 98%. Isobolograms were constructed (Tallarida et al, Pharmacol Ther, 2010) as well as a the synergy index (QUOTE 1-1/R) x 100 (%), where R = difference of areas between the line of additivity and the curve of synergy on the isobologram. This index represents how much of the obtained effect exceeds that expected by additivity of two chelators. Results Monotherapy with DFP, DFX or DFO at clinically relevant concentrations of 1 to 30µM iron binding equivalents (IBE), induced both dose and time dependent cellular iron removal. Dual therapy combinations of all 3 chelators enhanced iron removal at 4, 8 and 12 hours. At 4 hours of incubation, whereas 10µM DFO alone had no demonstrable effect on cellular iron removal, addition of DFP at as little as 1µM IBE increased cellular iron removal. Table 1 shows examples of cellular iron removal at specimen chelator concentrations alone or in combination at 8h. The combination of DFX with DFO, DFX with DFP and DFP with DFO all resulted in enhanced cellular iron removal. The combination of DFP and DFX was the most effective. Isobol plot analysis from multiple chelator concentrations demonstrated synergy for all pairs at 4 and 8 hours of exposure. The derived synergy index at 8h indicates that when DFX and DFO are combined, 49% of the chelation effect is due to synergy in this system and 51% in the case of DFP and DFO combination. Most interestingly, the synergistic effect is even greater, in the case of the two oral chelators DFP and DFX when in combination (59%). Figure 1. Conclusion Remarkably low concentrations of a second chelator are required to enhance cellular iron removal by the primary chelator. Isobol analysis shows synergy rather than additivity as the mechanism for enhanced chelation for all 3 combinations, implying a ‘shuttle’ and ‘sink’ effect. Interestingly, the combination of two oral chelators DFP and DFX showed the most marked enhancement of cellular iron removal, without cellular toxicity, suggesting a potentially powerful therapeutic approach, provided this is also well tolerated clinically. The long plasma half life of once daily oral DFX will allow a continuous ‘sink’ for iron shuttled by the shorter acting DFP. Line of Additivity Curve of Synergy below the line Disclosures: Porter: Novartis: Consultancy, Honoraria, Research Funding; Shire: Consultancy, Honoraria; Celgene: Consultancy.
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2013-11-15
    Description: Introduction Worldwide the greatest burden of disease related to beta thalassemia resides in Asia and is largely represented by Hemoglobin E beta thalassemia (HbE/thal) [Weatherall DJ, Ann New York Acad Sci 2005, 1054:11-17]. HbE/thal is the most common serious form of beta thalassemia in many Asian populations. In Sri Lanka, over 17 years, we have characterized over 200 affected patients and had proposed [Olivieri, NF, et al., J Pediatr Hematol Oncol, 2000, 22:593-597], as now shown in less common forms of non-transfusion dependent thalassemia [Taher AT, et al., Br J Haematol 2010, 150:486-489], that non-transfusional iron accumulation (NTIA) is a potential complication in non-transfused patients with HbE/thal. In 2009, we implemented R2-MRI [St Pierre, TG, et al., Blood 2005, 105:855-861] in Sri Lanka. Here we report the variation and severity of non-transfusional iron accumulation (NTIA), in parallel with screening tests of organ dysfunction, in a first group of patients with HbE/thal. Methods Patients aged 〉 7 years with clinical evidence of iron overload (generally a serum ferritin 〉 normal range in the absence of a history of regular transfusions) were recruited from The National Thalassaemia Centre (NTC), Kurunegala, Sri Lanka. LIC was measured using R2-MRI (FerriScan¨) with facilities situated a 6 hour return bus trip from the NTC. Liver function was evaluated using serum alanine transaminase (ALT). Fasting blood glucose (FBG), thyroid stimulating hormone (TSH), serum calcium and phosphate and serum ferritin (SF) were measured in local laboratories. Cardiac function was measured using echocardiography. Correlations between parameters were assessed using non-parametric (Spearman) analysis. Receiver operating characteristic (ROC) curve analysis was used to determine the optimum cut-off values of LIC and serum ferritin for predicting ALT values above the upper limit of the laboratory reference range. Results LIC measurements were successfully acquired for 110 of 112 enrolled subjects (45 male/ 67 female) with median age [range] 22.5 [7.8 – 61.5] years over 3 years. The variation in LIC was considerably, and unexpectedly, broad: median [range] LIC was 8.8 [0.7 – 65.0] mg Fe/g dw. LIC exceeded the threshold of risk established as 7.0 mg Fe/g dw [Olivieri NF, Brittenham GM, Blood 1997, 89:739-761] in a substantial proportion (57%) of patients. In parallel, organ dysfunction was observed: in a substantial group (52%), ALT was increased above normal range, while in 11%, ejection fraction was reduced (less than 56%). FBG and TSH were elevated above normal range in a substantial proportion of patients (6% and 30% respectively). Significant correlations were observed between LIC and serum ferritin concentration (r2=0.69, p
    Print ISSN: 0006-4971
    Electronic ISSN: 1528-0020
    Topics: Biology , Medicine
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...