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R Eckstein

Publications and source records attributed to R Eckstein.

At least 19 recordsLinked to original sources
PubMed2006

Comparison of the performance of microtube column systems and solid-phase systems and the tube low-ionic-strength solution additive indirect antiglobulin test in the detection of red cell alloantibodies.

To compare the performance of seven currently available test systems in the detection of erythrocyte alloantibodies (ab), we tested in parallel 446 sera samples containing red cell ab [368 sera samples with ab that are assumed to be clinically significant (cs-ab) and 78 sera samples with ab that are assumed to be of minor clinical significance (ms-ab)] using the tube spin low-ionic-strength solution (addition method) indirect antiglobulin test (tube LISS-IAT), three microtube column agglutination techniques (DiaMed-ID, Ortho BioVue and Bio-Rad Scangel), one affinity adherence test system (CLB/Mast CellBind Screen) and two solid-phase tests [Biotest Solidscreen II and Immucor Capture-R Ready-Screen (4)]. To address the specificity of the three test systems under routine conditions, results of 4566 patient samples obtained using the tube LISS-IAT, results of 5205 patient samples obtained using the Scangel and results of 3560 samples obtained using the Capture-R were evaluated. The DiaMed-ID detected 344 cs-ab and 43 ms-ab, BioVue 333 cs-ab and 48 ms-ab, Scangel 348 cs-ab and 62 ms-ab, CellBind Screen 346 cs-ab and 47 ms-ab, Solidscreen 330 cs-ab and 38 ms-ab, Capture-R 358 cs-ab and 45 ms-ab and LISS-IAT 159 cs-ab and 12 ms-ab. In routine practice, erythrocyte cs-ab could be identified in 61 (67.8%) of 90 reactive sera (specificity: 98.6%) in the tube LISS-IAT, in 169 (58.7%) of 288 (94.4%) in Bio-Rad Scangel and in 101 (51.0%) of 198 reactive sera (94.3%) in Capture-R. We conclude that the sensitivity of the microcolumn, affinity adherence and solid-phase test systems in the detection of cs-ab was similar and was markedly superior to that of the conventional tube LISS-IAT. All high-sensitive test systems produced higher rates of false positives and ms-ab compared to the tube test. An individual cost-benefit analysis, considering the recent knowledge about the clinical significance of weak-reactive cs-ab, should be performed in every institution to decide whether and if so which high-sensitive screening system should be applied.

Coombs Test↗
PubMed2006

Collection of hyperconcentrated platelets with Trima Accel.

BACKGROUND AND OBJECTIVES: Lowering the plasma content in single-donor platelet (PLT) concentrates well below 30% implies the need to collect platelets at very high concentrations. Trima Accel (TA) is validated for collection below 4000 x 10(3) PLTs/microl. We evaluated its performance at 5000 x 10(3) PLTs/microl. MATERIALS AND METHODS: Twenty blood donors underwent apheresis with TA twice collecting either a hyperconcentrated or a standard single-donor platelet concentrate with a target platelet concentration of 5000 or 1200 x 10(3) PLTs/microl, respectively. We analysed the collection efficiency, the collection rate and the quality of the collected by-plasma. RESULTS: We collected 20 hyperconcentrated and 20 standard units containing 2.56 +/- 0.5 and 3.39 +/- 0.4 x 10(11) PLTs at a concentration of 4518 +/- 978 and 1374 +/- 166 x 10(3) PLTs/microl in 45 +/- 8 and 39 +/- 6 min resulting in a collection efficiency of 47.5 +/- 10.0 and 70.7 +/- 7.9% and a collection rate of 5.9 +/- 1.4 and 8.8 +/- 1.5 x 10(9) PLTs/min, respectively (all results expressed as mean +/- standard deviation). The collected by-plasma showed a very high grade of cell purity and a satisfactory recovery of the clotting factors. CONCLUSION: Although TA is a suitable device for PLT collection at very high concentrations, improvements are desirable to further increase the productivity above its currently validated upper collect concentration limit.

Humans↗
PubMed2005

Hepatitis B virus vaccination of blood donors--what costs may be expected?

Although the risk of transfusion-transmitted hepatitis B virus (TT-HBV) infection is very low, it still exists. Therefore, introduction of further precautions to reduce this risk is discussed at present. However, so far no data are available about the HBV vaccination status among blood donors (BDs). We compared HBV vaccination status of apheresis donors (ADs) of a university based and whole BDs (WBDs) of a Red Cross blood donation service using a standardized questionnaire. On the basis of these data, the estimated costs over 10 years for HBV vaccination were calculated for two different strategies and compared with the costs for HBV nucleic acid amplification technology (NAT) testing. 22.3% of the WBDs and 41.2% of the ADs indicated having received at least one HBV vaccine dose. This difference was related to the different demographic structures of the two BD populations (BDPs). With regard to the primary costs for the blood donation service, HBV vaccination of BDs could be an alternative to HBV NAT testing, especially for BDPs with an already high HBV vaccination rate and a high donation frequency.

Adult↗
PubMed2005

Hyperconcentrated platelets stored in additive solution: aspects on productivity and in vitro quality.

BACKGROUND AND OBJECTIVES: New platelet (PLT) additive solutions (PASs) allow a plasma carryover of < 30% in PLT concentrates. This implicates the need to collect apheresis PLT concentrates at very high PLT concentrations: so-called dry PLTs (DPs). We used the TRIMA, with software version 4 (TRIMA V4), to collect such DPs and investigated the in vitro quality of these PLTs when stored in the new modified PAS-III (PAS-IIIM). MATERIALS AND METHODS: TRIMA V4 was programmed to collect 6.0 x 10(11) PLTs at a concentration of 5000 x 10(3) PLTs/microl. Two DPs were pooled, split into four equal parts and diluted to obtain secondary pools (SPs) consisting of 70% PAS-III/30% plasma, 70% PAS-IIIM/30% plasma, 80% PAS-IIIM/20% plasma or 100% plasma. In vitro testing was performed on days 0, 1, 5 and 7. Collection efficiency (CE), collection rate (CR) and PLT yield were calculated for each donation. RESULTS: Thirty-two runs with TRIMA V4 were performed, collecting 6.58 +/- 0.74 x 10(11) PLTs at a concentration of 4255 +/- 914 x 10(3)/microl in 99 +/- 19.9 min, resulting in a CE of 65.3 +/- 8.2% and a CR of 6.92 +/- 1.6 x 10(9) PLTs/min. On day 0, 34-37% of the PLTs in the units prepared for storage were already activated. PLTs stored in 70% or 80% PAS-IIIM showed superior in vitro quality compared to PLTs stored in PAS-III. CONCLUSIONS: TRIMA V4 is a suitable device for the collection of DPs. Nevertheless, improvements are desirable to further increase the ability to concentrate PLTs at very high levels. The storage of apheresis-derived PLTs in PAS III-M is a very promising approach, even at a plasma carryover of < 30%.

Blood Platelets↗
PubMed2004

The in vitro quality of washed, prestorage leucocyte-depleted red blood cell concentrates.

BACKGROUND AND OBJECTIVES: No data are currently available on the quality of washed prestorage leucocyte-depleted red blood cell concentrates (RCCs). MATERIALS AND METHODS: Five groups of RCCs stored in additive solution (SAG-M) were washed. The groups differed in the age of RCCs (2-5 days or 11-15 days), the temperature during the washing procedure and a 6-h storage period (4 degrees C or room temperature) and the washing solution (saline, SAG-M or 5% albumin). We measured ATP, 2,3-diphosphoglycerate (2,3-DPG), haemolysis, blood cell count, Na(+), K(+), pH, pO(2), pCO(2) and lactate, before and after the washing procedure and hourly during the 6-h postwash storage period. RESULTS: The erythrocyte ATP content increased by 2-13%, relative to the baseline value, during the washing procedure. The 2,3-DPG level decreased by 15-35% in 2-6-day-old RCCs and by 30-40% in 11-15-day-old RCCs (relative to baseline values) during the washing procedure. In RCCs that were washed and stored at room temperature, and in 2-week-old RCCs, a further decrease in 2,3-DPG of up to 40%, relative to the baseline value, was observed during the 6-h postwash time-period. CONCLUSIONS: Washing of RCCs stored in SAG-M results in a considerable, significant loss of erythrocyte 2,3-DPG, especially in older RCCs. This loss increases in during a 6-h storage period postwash, even at 4 degrees C. This loss of erythrocyte quality might well outweigh the benefits of washed SAG-M RCCs during massive transfusion in neonates.

2,3-Diphosphoglycerate↗
PubMed2003

Sample preparation technique and white cell content influence the detectable levels of growth factors in platelet concentrates.

BACKGROUND AND OBJECTIVES: Autologous platelet concentrate (PC) is applied locally to improve wound healing and tissue repair. Previous measurements of the growth factor content of platelets have given conflicting results. To date, there is no information on the influence of different preanalytical sample-preparation methods on the detectable amount of growth factors. MATERIALS AND METHODS: We measured the level of growth factors in PCs obtained by plateletpheresis and by leukapheresis. We subjected aliquots of these components to six different preparation methods: freezing/thawing once or twice; dissolution in 0.5% Triton-X-100; and clot formation by the addition of calcium and thrombin with subsequent incubation for 1 h, for 24 h, or for 1 h followed by freezing and thawing. RESULTS: In samples dissolved in Triton-X-100, higher levels of growth factors were detected than in the other specimens. In comparison to clot formation, freezing and thawing platelets twice was equivalent with respect to the release of platelet-derived growth factor (PDGF) but superior with respect to the release of transforming growth factor-beta1 (TGF-beta1). Overall, mean levels of 4.77 x 10(-16) g of PDGF-AB, 2.2 x 10(-17) g of PDGF-BB, and 2.41 x 10(-16) g of TGF-beta1 were found per single human platelet in white blood cell (WBC)-poor samples dissolved in Triton-X-100. CONCLUSIONS: Dissolving PC in Triton-X-100 releases maximum quantities of growth factors from platelets. The release of each growth factor by any sample preparation method should be investigated and interpreted separately. The preanalytical sample-preparation method, as well as the platelet and WBC content, influence the measurable levels of growth factors in PCs. The results implicate the need to correct, considerably upwards, previous estimations of the PDGF content of platelets.

Adult↗
PubMed2003

First comparison of productivity and citrate donor load between the Trima version 4 (dual-stage filler) and the Trima Accel (single-stage filler) in the same donors.

BACKGROUND AND OBJECTIVES: Aside from new software the blood cell separator TRIMA (GambroBCT) also received a newly designed separation chamber offering a novel single stage separation technology, called Trima Accel. We evaluated this new system focusing on productivity and donor comfort by comparing it to the previous version (Trima version 4) in collecting single-donor platelet concentrates (SD-PCs) and plasma. MATERIALS AND METHODS: Each of 20 donors underwent platelet apheresis using both devices. We compared the collection efficiency (CE), the collections rate (CR), the volume of the collected plasma and the residual leukocytes. Furthermore we compared donor comfort in terms of duration of the donation, flow of citrate back to the donor and platelet and white blood cell (WBC) loss. RESULTS: While the number of collected platelets and the platelet concentration did not differ significantly between both techniques the time of the procedure was reduced by 15.6% with Trima Accel. This results in an increase of the CR and CE of 25% and 15% respectively when using Trima Accel. Log normal probability plotting of WBC counts showed that both techniques complied with the European and the US leukoreduction guidelines. The mean flow of ACDA to the donor per minute and per litre blood volume was also reduced by 20%. CONCLUSION: These data show that the Trima Accel represents a further improvement in apheresis platelet production with a better productivity and donor comfort, especially regarding the mean flow of ACDA to the donor.

Adult↗
PubMed2001

Paired comparison of apheresis platelet function after storage in two containers.

Platelet quality after storage strongly depends on the pre-storage quality as well as on the storage conditions determined by the storage container. In this paired study, we evaluated two different containers (MedSep CLX and Delmed DPL-110). The Fresenius AS104 cell separator was used to prepare 17 platelet concentrates that were split and distributed into the containers to be compared. Cell counts, blood gas analysis, morphological scores, glucose and lactate levels, platelet activation, and platelet aggregation were measured before splitting at the day of preparation and after storage at day 3 and day 5. At day 3, there was no significant difference between the two bags apart from increased lactate and decreased pCO(2) concentrations in the CLX bags. At day 5 there were significantly higher lactate concentrations, pO(2) levels, and aggregation after stimulation in the CLX group, while the glucose and pCO(2) concentrations were significantly lower in these platelet concentrates as compared to the DPL-110 group. However, these parameters did not influence the functional parameters tested. While the platelet quality decreased during storage in all bags, the functional changes were nearly identical in both bags tested. We conclude that both bags are equivalent for 5-day storage of platelet concentrates.

Blood Preservation↗
PubMed2001

Storage of single donor platelet concentrates: paired comparison of storage as single or double concentrates.

Modern cell separators allow the collection of two plateletpheresis concentrates (PCs) at one session. This study evaluates the quality of PCs stored as double concentrates in standard storage containers of two manufacturers. We collected 20 PCs that contained 4.5 x 10(11) platelets in 375 ml plasma (10 using the COBE Spectra and 10 using the Fresenius AS.TEC 204 with 500 ml bags) that were split into one unit of 3.0 x 10(11) platelets in 250 ml (3.0-PC) and one of 1.5 x 10(11) platelets in 125 ml (1.5-PC). Storage of one 3.0-PC per bag of a two-bag system corresponded to storage conditions for double PCs and storage of one 1.5-PC per bag to storage conditions of single PCs. Cell counts, blood gas analysis, glucose and lactate levels, platelet aggregation, and activation and plasma levels of beta- thromboglobulin (beta-TG) and complement factor 3a (C3a) were measured before storage and again on days 3 and 5. COBE 3.0-PCs demonstrated less pH rise, lactate production, CD 62P expression and beta-TG plasma levels, and better aggregability after storage than COBE 1.5-PCs. Fresenius 1.5-PCs had similar platelet quality to COBE 3.0-PCs. Fresenius 3.0-PCs showed a fall of pH (day 5: 6.22 +/- 0.56), the highest amount of anaerobic glycolysis compared to all other storage conditions investigated, high CD 62P- expression and beta-TG plasma levels, and impaired aggregability on days 3 and 5. The highest C3a levels were found in COBE 1.5-PCs. 3.0 x 10(11) platelets in 250 ml plasma should be stored either in one bag of the COBE system or in two 500 ml bags of the Fresenius system. The COBE two-bag system allows the storage of two PCs without loss of platelet quality. Two PCs should not be stored in the Fresenius C4L 500 ml storage containers.

Blood Chemical Analysis↗
PubMed2001

Collection of MNCs with two cell separators for adoptive immunotherapy in patients with stage IV melanoma.

BACKGROUND: MNCs for adoptive immunotherapy may be collected by leukocytapheresis with a cell separator. STUDY DESIGN AND METHODS: Six healthy cytapheresis donors donated two MNC concentrates on a cell separator (AS.TEC 204, Fresenius): one on the standard MNC program and one on a modified MNC program with reduced centrifuge velocity that leads to a lower platelet contamination. Seventeen patients with malignant melanoma donated 26 MNC concentrates: 5 on the AS.TEC 204 MNC program, 9 on the modified AS.TEC 204 MNC program, and 12 on another modified MNC program (Spectra, COBE). RESULTS: In the course of cultivation of MNCs to dendritic cells (DCs), the donor MNC concentrates with the lower platelet contamination (475 +/- 85 x 10(9)/L) had a significantly higher relative DC yield (low platelet contamination: 3.9 +/- 1.6% of the plated cells; high platelet contamination: 2.5 +/- 1.8% of the plated cells; p = 0.019) than the concentrates with the higher platelet contamination (2364 +/- 448 x 10(9)/L). No significant difference was found in the yields of MNCs and CD14+ cells in the three protocols used for the collection of MNCs from patients with melanoma. The components obtained by the standard AS.TEC 204 MNC program had a significantly higher platelet contamination (1768 +/- 994 x 10(9)/L) than the components obtained by the modified AS.TEC MNC program (360 +/- 98 x 10(9)/L; p<0.05) and the modified Spectra MNC program (636 +/- 266 x 10(9)/L); p<0.05). Because of the low number of investigated components, no significant difference in the DC yield of the three protocols could be detected (mean DC yield after cultivation: 746 +/- 429 x 10(6)). CONCLUSION: A high platelet contamination of MNC concentrates intended for adoptive immunotherapy can lead to a significant impairment of the DC yield after cultivation. Both the modified AS.TEC 204 and the modified Spectra MNC programs are well suited for collecting MNC concentrates with high MNC yields and low platelet contamination from patients with malignant melanoma.

Adult↗
PubMed2001

The variability of compensatory erythropoiesis in repeated autologous blood donation.

BACKGROUND: Compensatory RBC production during repeated preoperative autologous blood donation (PABD) shows marked interindividual variability. This study was performed to reveal variables that might be useful to predict the amount of the erythropoietic response to PABD in an individual patient who was not iron deficient. STUDY DESIGN AND METHODS: In a retrospective study, 104 adult patients, 48 women and 56 men (mean age, 59.9 years; range, 18-82 years) who donated 3 units (450 mL) of autologous blood at weekly intervals for major surgery were investigated. Blood counts, ferritin, and net preoperative RBC production (net RBC production) were determined in all patients, and soluble transferrin receptor and endogenous levels of EPO, SCF, and IL-1beta were measured in 63 patients. Multiple linear regression analysis was used to determine whether the variance of net RBC production was attributable to baseline values of these variables. RESULTS: Net RBC production was not different in patients who received oral iron and patients who did not (384 +/- 222 mL vs. 356 +/- 158 mL). In both groups, the same two variables consistently showed a significant relationship to net RBC production: the length of the period between the third donation and the last visit was positively related (p = 0.00001 vs. p = 0.0002) and the Hct at baseline was negatively related (p = 0.0002 vs. p = 0.02) with net RBC production. The proportion of variance in net RBC production that was attributable to these two variables was 48.1 percent (r(2) = 0.481) and 34.9 percent (r(2) = 0.349), respectively. CONCLUSION: RBC production after PABD increases with increasing interval from last donation to surgery. This suggests that the interval from last donation to surgery should be maximized. This can be achieved by organizational measures in combination with the preparation of RBC concentrates in additive solution with a maximum shelf life.

Adolescent↗
PubMed2001

Effect of gamma radiation on the in vitro aggregability of WBC-reduced apheresis platelets.

BACKGROUND: The effect of gamma radiation on single-donor apheresis platelet concentrates (SDPs) has been elucidated only incompletely. The only existing report on the function of SDPs stored in the irradiated state found a deterioration in the in vitro aggregability at the end of shelf life in SDPs divided before irradiation with 1500 cGy. STUDY DESIGN AND METHODS: The in vitro properties of platelets were examined in four series of irradiated and control platelets, each obtained from the same 15 donors. Irradiation with 3000 cGy was performed on Days 0, 3, and 5. Cellular content, aggregability by ADP alone or ADP and epinephrine, spontaneous and induced CD62 expression, beta-thromboglobulin release, glucose consumption, lactate production, and pH were measured immediately after preparation and on Days 3 and 5 after donation. RESULTS: Comparable in vitro properties were measured in irradiated and control platelets, whether irradiation was performed on Day 3 or Day 5. However, in platelets irradiated on Day 0, we found a significantly better in vitro aggregability by 20 microM: ADP immediately after irradiation and by 10 microM: ADP and 2 microM: epinephrine at the end of shelf life than was found in the other groups (Day 5 results: Day 0 irradiation: 75 +/- 32%; Day 3 irradiation: 45 +/- 45%; Day 5 irradiation: 47 +/- 41%; control: 40 +/- 24%; p<0.05). CONCLUSION: Gamma radiation had no adverse effect on platelet quality in extremely WBC-reduced SDPs. On the contrary, a slight, but significantly better in vitro aggregability was found in SDPs irradiated before storage than in platelets irradiated later during storage and in unirradiated platelets. This increased in vitro aggregability persisted until the end of shelf life.

Adenosine Diphosphate↗
PubMed2001

Comparison of a new WBC-reduction system and the standard plateletpheresis protocol in the same donors.

BACKGROUND: A cell separator (Spectra, Gambro BCT) with an integrated leukoreduction system (LRS) for producing WBC-reduced single-donor platelet concentrates has been shown to result in a slightly reduced collection efficiency as compared to the former Spectra system without LRS. A novel modified system for improved collection efficiencies (LRS Turbo, Gambro BCT) was evaluated. STUDY DESIGN AND METHODS: Each of 37 donors underwent plateletpheresis using the LRS Turbo (LRS-T) and the standard LRS (LRS) of the Spectra cell separator. The collection efficiency and WBC contamination of the different techniques were compared. Platelets were counted automatically and WBCs were counted by using one or two full grids of a Nageotte chamber. RESULTS: The preseparation and postseparation numbers of RBCs, WBCs, and platelets, as well as the number of collected platelets, did not differ for the two techniques. In the LRS-T separations, the collection efficiency was 112 percent of that in the LRS procedures. Median residual WBCs in the platelet components were 0.0256 x 10(6) per LRS-T procedure and 0.0253 x 10(6) per LRS procedure. The purity of the LRS-T components was not less than that of the standard LRS components, whereas the collection efficiency of the LRS-T was significantly greater, 44.9 percent versus 40.7 percent. CONCLUSIONS: The LRS-T procedures produced platelet concentrates with WBC-reduction capacity that is comparable to that obtained with the standard LRS procedures, which have previously been described as satisfying the most stringent criteria for WBC-reduced platelets. The new technique significantly improved the collection efficiency of the plateletpheresis procedure.

Blood Donors↗
PubMed2001

Different preparation methods to obtain platelet components as a source of growth factors for local application.

BACKGROUND: Autologous platelet components were recently used as part of tissue-engineering strategies in oral and maxillofacial surgery. Various preparation methods were investigated to define standardized blood bank components and to collect data on the growth factor content of human platelets before and after storage. STUDY DESIGN AND METHODS: Apheresis platelets (AP), buffy coat-derived platelets (BCP), platelets prepared by tube method (TP), and highly concentrated samples prepared from AP and from BCP were evaluated for standard quality criteria of platelet components and for their concentration of transforming growth factor (TGF)-ss1, platelet-derived growth factor (PDGF)-AB, and PDGF-BB. AP were stored for 5 days. On Days 3 and 5, these components and freshly prepared, highly concentrated samples were evaluated for the same measures. RESULTS: Platelet concentration in TP was lower than that in the other groups (p<0.05). However, the concentrations of PDGF-AB, PDGF-BB, and TGF-ss1 were comparable in the three groups. TP showed higher spontaneous CD62 expression than did AP and BCP. The three preparation procedures resulted in significantly different WBC contamination, with the highest levels in TP. For the whole series of measurements, there was a strong correlation between growth factor levels and platelet concentration (p<0.05), which was due to the face that the growth factor content of concentrated platelet samples was tenfold that of AP, BCP, and TP. In TP, the WBC concentration was correlated with PDGF levels (p<0.05). After 5-day storage, the mean levels of PDGF-AB, PDGF-BB, and TGF-ss1 were 57.1, 43.0, and 72.0 percent of the initial values in AP. Overall, multiple regression analysis revealed the following factors influencing the measured growth factor concentrations: platelet concentration, baseline CD62 expression, lactate production, and WBC contamination. CONCLUSION: Various methods enable the preparation of platelet components and of highly concentrated components for local use according to standard blood banking criteria. The obtained components differ, particularly in their WBC content and in vitro platelet activation. These findings are relevant for planning and evaluating further studies of locally usable autologous platelet components.

Blood Platelets↗
PubMed2000

Mutations associated with microsatellite unstable colorectal carcinomas exhibit widespread intratumoral heterogeneity.

Although microsatellite instability (MSI) has been shown to be present in 15% of sporadic colorectal carcinomas, the genetic events underlying the development of these tumors have not been well described. By investigating intratumoral heterogeneity, this study attempts to elucidate whether MSI-positive colorectal carcinomas develop as the result of a random accumulation of mutations or as an ordered, stepwise sequence of genetic alterations. Eighty-six regions from 16 MSI-positive sporadic colorectal carcinomas were examined for mutations in repeat nucleotide sequences of the tumour suppressor genes transforming growth factor beta type II receptor (TGFBRII), insulin-like growth factor II receptor (IGFIIR), and BAX, and the mismatch repair genes MSH3 and MSH6. At least 2 and up to 5 of these genes were mutated in each tumour, and widespread intratumoral heterogeneity was observed for each gene. Regions of tumour with TGFBRII mutations were correlated with a poorly differentiated histology. Unlike the situation in microsatellite stable colorectal carcinomas, the findings of the present study did not suggest that a particular sequence of tumour suppressor and mismatch repair genes are mutated during colorectal tumorigenesis. It seems likely that a random accumulation of mutations, as a result of a defect in the mismatch repair pathway, drives tumour progression in this type of colorectal carcinoma.

Colorectal Neoplasms↗