bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cell loss and recovery in umbilical cord blood processing: a comparison of postthaw and postwash samples
Authors: Laroche Vincent , McKenna David H. , Moroff Gary , Schierman Therese , Kadidlo Diane , McCullough Jeffrey 
Published: October 2005

BACKGROUND: Engraftment after umbilical cord blood (UCB) transplantation is highly dependent on nucleated cell (NC) and CD34+ cell content. Current standard postthaw (PT) processing includes a wash step to remove dimethyl sulfoxide (DMSO), lysed red cells, and stroma. The contribution of the wash step to cell loss and ultimately the dose of cells available for transplant have yet to be systematically reported. This study examines the effect of the wash step as well as that of PT storage on various quality control variables of UCB units.STUDY DESIGN AND METHODS: Ten units were thawed and washed based on the New York Blood Center method. Samples were removed from each unit at six time points: prefreeze (PF), immediately PT, immediately postwash (PW), and 1, 2, and 5 hours PW. On each sample, total nucleated cell (TNC) count, CD34+ cell enumeration, colony‐forming unit (CFU)–granulocyte‐macrophage, and viability assays (fluorescence microscopy [acridine orange/propidium iodide, or AO/PI] and flow cytometry [7‐aminoactinomycin]) were obtained.RESULTS: TNC counts decreased PT and at subsequent time points; the PT TNC recovery was 89 percent compared to 82 percent PW (p < 0.01). TNC recovery decreased to 90 percent of PW (82% of PT) values (p < 0.01) and 83 percent of PW (76% of PT) values (p < 0.001), at 2 and 5 hours PW, respectively. CD34+ cell loss PT was not significant. Viability by AO/PI decreased PT and plateaued over time. In contrast, viability by flow cytometry remained higher and increased slightly over time. CFUs were significantly lower PT, recovering PW.CONCLUSIONS: Our data indicate that the thawing and washing results in a substantial loss of cells, with TNC loss approaching 20 percent when compared with PF counts; the wash step was responsible for nearly half of the cell loss. The reduced PT viability was expected. Elapse of time PW resulted in further loss of NCs but no detectable significant changes in CD34+ cell content and viability and/or CFU.
Clinical safety of platelets photochemically treated with amotosalen HCl and ultraviolet A light for pathogen inactivation: the SPRINT trial
Authors: Snyder Edward , McCullough Jeffrey , Slichter Sherrill J. , Strauss Ronald G. , Lopez‐Plaza Ileana , Lin Jin‐Sying , Corash Laurence , Conlan Maureen G. ,   SPRINT Study Group
Published: October 2005

BACKGROUND:  A photochemical treatment (PCT) method utilizing a novel psoralen, amotosalen HCl, with ultraviolet A illumination has been developed to inactivate viruses, bacteria, protozoa, and white blood cells in platelet (PLT) concentrates. A randomized, controlled, double‐blind, Phase III trial (SPRINT) evaluated hemostatic efficacy and safety of PCT apheresis PLTs compared to untreated conventional (control) apheresis PLTs in 645 thrombocytopenic oncology patients requiring PLT transfusion support. Hemostatic equivalency was demonstrated. The proportion of patients with Grade 2 bleeding was not inferior for PCT PLTs.STUDY DESIGN AND METHODS:  To further assess the safety of PCT PLTs, the adverse event (AE) profile of PCT PLTs transfused in the SPRINT trial is reported. Safety assessments included transfusion reactions, AEs, and deaths in patients treated with PCT or control PLTs in the SPRINT trial.RESULTS:  A total of 4719 study PLT transfusions were given (2678 PCT and 2041 control). Transfusion reactions were significantly fewer following transfusion of PCT than control PLTs (3.0% vs. 4.1%; p = 0.02). Overall AEs (99.7% PCT vs. 98.2% control), Grade 3 or 4 AEs (79% PCT vs. 79% control), thrombotic AEs (3.8% PCT vs. 3.7% control), and deaths (3.5% PCT vs. 5.2% control) were comparable between treatment groups. Minor hemorrhagic AEs (petechiae [39% PCT vs. 29% control; p < 0.01] and fecal occult blood [33% PCT vs. 25% control; p = 0.03]) and skin rashes (56% PCT vs. 42% control; p < 0.001) were significantly more frequent in the PCT group.CONCLUSION:  The overall safety profile of PCT PLTs was comparable to untreated PLTs.
Removal of exogenous (spiked) and endogenous prion infectivity from red cells with a new prototype of leukoreduction filter
Authors: Sowemimo‐Coker Samuel , Kascsak Regina , Kim Anzi , Andrade Fabiola , Pesci Susan , Kascsak Richard , Meeker Clifford , Carp Richard , Brown Paul 
Published: October 2005

BACKGROUND: Two recent probable cases of transmission of a variant of human Creutzfeldt‐Jakob disease (vCJD) through blood transfusion suggest that the disease can be transmitted through transfusion of blood components from presymptomatic blood donors. In the absence of a preclinical screening test, removal of the infectious agent by processing is the only means by which risk to recipients of blood from donors with inapparent vCJD infections can be eliminated.STUDY DESIGN AND METHODS: In the endogenous infectivity study, a pool of 500 mL of whole blood was collected into CP2D anticoagulant from 263K‐strain scrapie‐infected hamsters, processed into 300 mL of red cells (RBCs), and then passed through a prion removal filter. Pre‐ and postfiltration samples were tested for PrPsc by Western blot and for infectivity by inoculation of healthy hamsters. In the exogenous (spiking) infectivity study, 30 mL of 10 percent (wt/vol) scrapie‐infected brain homogenates was added to 270 mL of human RBCs and then filtered. Levels of PrPsc and infectivity were determined by Western blot and bioassay.RESULTS: In the endogenous infectivity study, the prefiltered RBCs transmitted disease to 6 of 43 animals, whereas the postfiltered RBCs did not transmit disease to any of 35 animals, and a barely visible prefiltration PrPsc Western blot signal was reduced below the level of detection in the postfiltration sample. In the exogenous (spike) study, infectivity was reduced by 3.7 log LD50 per mL, from 9.2 to 5.5 log LD50 per mL.CONCLUSION: The new filter was effective in removing both infectivity and PrPsc from RBCs. The use of this type of filter should reduce the risk of vCJD transmission through blood transfusion.
The impact of e‐mail in acquiring and retaining whole‐blood donors: a comparative analysis of the Puget Sound Blood Center donor e‐mail communication program
Authors: Geyer Maria Elena 
Published: October 2005

BACKGROUND: With the emergence of e‐mail as a common form of communication, it is important to understand the role and impact e‐mail can have on acquiring and retaining whole‐blood donors.STUDY DESIGN AND METHODS: Whole‐blood donors who opted in to receive e‐mail communications (n = 43,232) from the Puget Sound Blood Center (PSBC) and as a result participated in one or more of five e‐mail marketing campaigns between July 2002 and March 2003 were studied.RESULTS: New donors with e‐mail addresses grew by 74 percent over the measurement period compared with 2 percent growth of those without e‐mail addresses. Nearly 15,000 prospective donors were reached as a result of donors passing along e‐mails they received from PSBC to friends and family. Nearly 5 percent of PSBC e‐mail campaign recipients registered to donate online. PSBC e‐mail campaigns have outperformed e‐mail marketing industry mean open rates by 44 percent and click‐through rates by 36 percent.CONCLUSION: E‐mail is now a mainstream communication medium. It has proven to be an effective method of reaching new donors and generating new donation registrations. Donors respond more favorably to e‐mail communications from PSBC compared with e‐mail they receive from other organizations. Deeper understanding of how different segments of blood donors use e‐mail may help blood centers adjust their donor acquisition and retention programs. New recruitment methods are needed to grow the overall donor base, and e‐mail appears to have the potential to make a significant contribution to meeting this objective.
Cryopreservation of hematopoietic progenitor cells from apheresis at high cell concentrations does not impair the hematopoietic recovery after transplantation
Authors: Martin‐Henao Gregorio Angel , Torrico Carlos , Azqueta Carmen , Amill Begoña , Querol Sergio , Garcia Juan 
Published: October 2005

BACKGROUND: The high number of nuclear cells (NCs) from hematopoietic progenitor cells‐apheresis (HPC‐A) requires cryopreservation in large volumes or at high NC concentrations. The effect of NC concentration during cryopreservation has yet to be examined.STUDY DESIGN AND METHODS: In the experimental arm (n = 610, Protocol B), the first HPC‐A sample from the patient was cryopreserved in two cryobags and subsequent collections in one cryobag, resulting in high NC concentrations (>100 × 106 NCs/mL) in most cases. The effect of NC concentrations at freezing in NC recovery after thawing and engraftment kinetics was analyzed and compared with a group of HPC‐A cryopreserved at standard NC concentrations (n = 455, Protocol A).RESULTS: The mean (SD) NC concentration at freezing was 78 (28) × 106 per mL (median, 82 × 106/mL; range, 12 × 106‐156 × 106/mL) and 183 (108) × 106 per mL (median, 156 × 106/mL; range, 16 × 106‐678 × 106/mL), for HPC‐A cryopreserved according to Protocols A and B, respectively. The NC viabilities of the test vials and HPC‐A components after thawing were 88 percent versus 85 percent and 85 percent versus 82 percent, and the cloning efficiency was 49 percent versus 33 percent for Protocols A and B, respectively (p < 0.001). Significant differences were not observed in the recovery of NCs. Days to neutrophil and platelet engraftment were not different between patients transplanted in the standard‐ (n = 143) or high‐cell‐concentration group (n = 238).CONCLUSION: The cryopreservation of HPC‐A at higher than standard NC concentrations has no adverse impact on hematopoietic reconstitution after transplantation.
Freezing human platelets with 6 percent dimethyl sulfoxide with removal of the supernatant solution before freezing and storage at −80°C without postthaw processing
Authors: Valeri C. Robert , Ragno Gina , Khuri Shukri 
Published: October 2005

BACKGROUND: Platelets (PLTs) can be frozen with 6 percent dimethyl sulfoxide (DMSO) at −80°C for up to 2 years. This method has been modified by concentrating the PLTs and removing the supernatant before freezing.STUDY DESIGN AND METHODS: High‐yield leukoreduced PLTs stored at 22°C for up to 5 days were divided into three equal volumes: one was frozen with 6 percent DMSO at −80°C, thawed, washed, and resuspended in plasma (old method with DMSO); the second was treated with 6 percent DMSO, concentrated to remove the supernatant DMSO, frozen at −80°C, thawed, and diluted with 0.9 percent NaCl (new method with DMSO); and the third was treated with 0.9 percent NaCl without DMSO, concentrated to remove the supernatant solution, frozen at −80°C, thawed, and diluted with 0.9 percent NaCl (new method without DMSO).RESULTS: Freeze‐thaw‐wash recovery of PLTs frozen by the old method with DMSO was 74 ± 2 percent with 5 percent PLT microparticles. Freeze‐thaw recovery was 94 ± 2 percent with 7 percent PLT microparticles (new method with DMSO) and 69 ± 9 percent with 15 percent PLT microparticles (new method without DMSO). Total DMSO in washed PLTs was 400 and 600 mg in PLTs concentrated before freezing. In vivo recovery of PLTs frozen by the new method with DMSO and transfused into normal volunteers was 30 percent and the life span was 7 days.CONCLUSION: Concentrating PLTs before freezing simplified the procedure by eliminating postthaw washing. PLTs frozen by this method had more PLTs with reduced GPIb and increased annexin V binding than those frozen by the old method.
Is an assay for simultaneous detection of hepatitis C virus core antigen and antibody a valuable alternative to nucleic acid testing?
Authors: Laperche Syria , Elghouzzi Marie‐Hélène , Morel Pascal , Asso‐Bonnet Marianne , Le Marrec Nadine , Girault Annie , Servant‐Delmas Annabelle , Bouchardeau Françoise , Deschaseaux Marie , Piquet Yves 
Published: October 2005

BACKGROUND: A new enzyme immunoassay based on the simultaneous detection of nucleocapsid proteins of hepatitis C virus (HCV) and anti‐HCV (Monolisa HCV antigen‐antibody Ultra, Bio‐Rad) was evaluated as an alternative to nucleic acid testing (NAT) for the diagnosis of HCV infection during the window period in blood donations.STUDY DESIGN AND METHODS: The study included 107 sequential samples from 10 HCV seroconversion commercial panels; 81 samples were in the preseroconversion phase, and 26 were collected after seroconversion. All samples were tested with HCV antigen‐antibody assay and the two minipool (MP) NAT procedures that are routinely used in France (transcription‐mediated amplification in pools of 8 and COBAS AmpliScreen HCV test [Roche Diagnostic] in pools of 24 donations).RESULTS: From the 44 samples collected during window period that were MP‐NAT–positive, 31 (70.5%) were also positive with the Monolisa HCV antigen‐antibody assay. The mean delay in detecting HCV infection between these two methods was 5.1 days (range, 0‐24 days). The Monolisa HCV antigen‐antibody assay led to a reduction in the window period of 26.8 days (range, 0‐72 days). All samples collected after seroconversion were detected with the HCV antigen‐antibody assay. The specificity analyzed in 2503 consecutive blood donations was estimated at 99.88 percent.CONCLUSION: This new developed assay presents an improvement for the detection of HCV infection, especially in the early phase of infection when antibodies are undetectable. Although less sensitive than NAT, this assay could be a suitable solution for blood screening in developing countries where NAT (or HCV core antigen–specific assay) is not affordable or its implementation is not feasible.
Intraoperative Testing of the Implantable Cardioverter‐Defibrillator: How Much Is Enough?
Authors: PIRES LUIS A. , JOHNSON KATRINA M. 
Published: October 2005

Introduction: Defibrillation testing of the implantable cardioverter‐defibrillator (ICD) is considered a standard and required practice at the time of implantation. How much testing, if any in some cases, should be performed, however, remains unknown. Methods and Results: Included in this retrospective analysis were 835 patients (77% men; age 65 ± 13 years) who received transvenous ICDs between January 1996 and December 2003. One hundred twenty‐nine (15.5%) had intraoperative defibrillation threshold (DFT) testing, 503 (60.2%) had limited defibrillation safety margin testing, and 203 (24.3%) had no defibrillation testing. We compared the outcome (success of ICD therapies against spontaneous VT/VF events and survival) of the three groups of patients, who in some respects had important clinical differences. The success of the first delivered shocks against VT/VF was similar for DFT (91%), safety margin testing (91%), and no‐testing (92%) groups; and the second shocks terminated the remaining episodes in all three groups. Sudden‐death‐free survival rates were similar in the three groups, however, the overall long‐term survival rate was significantly lower in the no‐testing group (58%) than in the DFT (74%) and safety margin testing (69%) groups (P < 0.0005). Multivariate analysis found no strong predictors of sudden death, but there were several independent predictors of overall mortality including lack of ICD testing (HR: 2.031, CI: 1.253–3.290, P = 0.004). Conclusion: In this select patient cohort, success of ICD therapies and sudden‐death‐free survival were similar in patients who had DFT, safety margin testing, and no testing, but overall survival was significantly lower in the no‐testing group. Thus in the absence of prospective mortality data, a minimum of safety margin ICD testing should remain standard practice.
The Mechanisms of an Increased Dominant Frequency in the Left Atrial Posterior Wall During Atrial Fibrillation in Acute Atrial Dilatation
Authors: HUANG JIN‐LONG , TAI CHING‐TAI , LIN YENN‐JIANG , TING CHIH‐TAI , CHEN YING‐TSUNG , CHANG MAU‐SONG , LIN FAN‐YUE , LAI WEN‐TER , CHEN SHIH‐ANN 
Published: October 2005

Background: Previous studies have shown that the highest dominant frequency (DF) is located in the left atrium (LA) during atrial fibrillation (AF) in pacing‐induced AF. However, there have been few studies on the mechanisms of the increased DF of AF during acute atrial dilatation. The purpose of this study was to investigate the mechanisms of the increased maximal DF (max DF) in pacing‐induced AF during acute atrial dilatation. Methods: In eight Langendorff‐perfused canine hearts (26 ± 2 kg), noncontact balloon catheters were placed into the right atrium (RA) and LA, respectively. AF was induced by extrastimulation pre‐ and postdilatation in the atrium (0 and 15 cm H2O, respectively). Fast Fourier transformation analysis was performed to analyze the max DF and harmonic index (HI) from the bi‐atrial unipolar virtual electrograms during AF. The fibrillation cycle lengths were obtained from different atrial sites. The number of wavefronts was analyzed during AF. The frequency of regional splitting was defined as the number of wavefront splits per second in different atrial regions during AF. The percentage of the low‐voltage zones (<0.5 mV) was defined as the ratio of the area of the low‐voltage zones to the total atrial surface area. Results: The DF was measured during AF. The shortest fibrillation cycle length was located in the LA posterior wall and became shorter during acute atrial dilatation. The max DF was located in the LA posterior wall and increased during acute atrial dilatation (7.1 ± 0.8 vs 8.8 ± 2.1, P = 0.02). The max DF of the LA correlated with the wavefront number (r = 0.797, P < 0.001 predilatation; r = 0.860, P < 0.001 postdilatation). The splitting of wavefronts facilitated the formation of new wavefronts. During acute atrial dilatation, the frequency of regional splitting was closely correlated with the percentage of the low‐voltage zones (r = 0.876, P < 0.001). Furthermore, the LA posterior wall had a higher percentage of the low‐voltage zones than the other sites. Conclusion: In acute atrial dilatation, the percentage of the low‐voltage zones increased, especially in the LA posterior wall, which correlated with the regional splitting of the AF wavefronts. The increase in the splitting facilitated the formation of new wavefronts and resulted in a higher max DF during acute atrial dilatation.
Biventricular Pacing Has an Advantage over Left Ventricular Epicardial Pacing Alone to Minimize Proarrhythmic Perturbation of Repolarization
Authors: HARADA MASAHIDE , OSAKA TOSHIYUKI , YOKOYAMA ERIKO , TAKEMOTO YOSHIO , ITO ATSUSHI , KODAMA ITSUO 
Published: October 2005

Introduction: Cardiac resynchronization therapy (CRT) by simultaneous biventricular pacing is now widely accepted as a new therapeutic option for patients with severe congestive heart failure (CHF). Recent studies have shown comparable hemodynamic benefits of left ventricular (LV) pacing alone. The clinical usefulness of CRT, however, might be compromised by potential exaggeration of arrhythmogenic substrates through a modification of ventricular repolarization. Methods and Results: We compared ECG parameters during sinus rhythm (SR), atrioventricular synchronous pacing at the right ventricular apex (RVendP), at LV epicardium (LVepiP), and at both sites (BiVP) in acute homodynamic studies of 14 CHF patients scheduled for CRT (QRS duration = 144 ± 23 msec, LVEF = 27 ± 10%). The maximum rate of increase in LV pressure (LVdp/dtmax) was decreased significantly during RVendP, whereas it was increased similarly during LVepiP and BiVP compared with SR. QTc was increased during RVendP (by 10.2%) and LVepiP (by 26.1%). QTc dispersion (QTcmax‐QTcmin in the six precordial leads) was also increased during LVepiP (by 66.5%). These parameters were unaffected during BiVP. JTc was unchanged, and the interval from the peak to the end of the T wave (Tcpeak‐end) was increased slightly (by 19.3%) during RVendP. Both JTc and Tcpeak‐end were increased dramatically during LVepiP (by 18.2% and 55.4%, respectively), but increased only modestly during BiVP (by 6.6% and 15.8%, respectively). Conclusions: LVepiP causes much greater increase in spatial dispersion of ventricular repolarization than BiVP in CHF patients. BiVP may have a substantial advantage over LVepiP to minimize the proarrhythmic perturbation of ventricular repolarization in association with CRT.
Left Ventricular Lead Placement Within a Coronary Sinus Side Branch Using Remote Magnetic Navigation of a Guidewire: A Feasibility Study
Authors: RIVERO‐AYERZA MAXIMO , THORNTON ANDREW S. , THEUNS DOMINIC A.M.J. , SCHOLTEN MARCOEN F. , MEKEL JORIS M. , RES JAN , JORDAENS LUC J. 
Published: October 2005

Background: A novel magnetic navigation system (MNS) allowing remote guidance of catheters and guidewires might assist in implantation of left ventricular (LV) pacing leads. Objective: To assess the feasibility of deploying a LV pacing lead into a coronary sinus (CS) side branch using a magnetically guided wire and of performing the procedure without a CS guiding sheath. Methods: Twenty‐one patients were included in this study. Nine underwent CRT device implantation using a MNS to steer the guidewire (MNS group) while 12 patients were conventionally implanted (control group). In 6 patients in the MNS group, the procedure was performed using a CS guiding sheath. In 3 others, the decision was to perform the procedure without a CS sheath. In these patients the wire was advanced manually, while the external magnets oriented it toward the CS os. In the CS, “vector based” navigation was used to guide the wire to the desired side branch. Results: In all 9 patients in the MNS group, the target vessel could be successfully engaged by the magnetically guided wire. In 7, the LV lead was lodged in the target vessel. In 2 patients, the LV lead was repositioned in an anterolateral side branch due to instability or inability to engage the vessel with it. Mean total procedure time was 164 ± 58 minutes (without sheath 229 ± 52 vs with sheath 132 ± 26 minutes; P = 0.007). Mean fluoroscopy time was 28 ± 9 minutes. For control patients, the procedure and fluoroscopy time were similar (144 ± 41 minutes and 26 ± 12 minutes, respectively). No major complications occurred. Conclusion: LV lead implantation can be performed using a remote magnetically steered guidewire. Though the lead could be implanted without a CS guiding sheath, longer procedure times were required.
Factors influencing low‐molecular‐weight solute clearance during hemodialysis
Authors: Huang Zhongping , Clark William R , Gao Dayong 
Published: October 2005

AbstractThe relationship between delivered urea Kt/V and survival has raised concerns in recent outcome trials in chronic dialysis patients. Nevertheless, measurement of delivered small solute clearance remains the most common approach to quantify therapy. The purpose of this review is to provide an overview of the numerous factors influencing small solute clearance during hemodialysis. Although the focus of the review is on the manner in which dialyzer characteristics influence small solute clearances, factors related to other aspects of the extracorporeal circuit and to the patient will also be discussed.
Effect of mineralocorticoids on interdialytic weight gain in hemodialysis patients with perdialytic hypotension
Authors: Mercadal Lucile , Petitclerc Thierry 
Published: October 2005

AbstractFludrocortisone is recommended in patients with orthostatic hypotension and a benefit has been suggested in hemodialysis patients with severe hypokaliemia. We report 2 patients who suffered from chronic severe perdialytic hypotension resistant to midodrine and who were treated in a long‐term period with fludrocortisone. A rise of post‐dialytic BP was observed with a decrease of the interdialytic weight gain (IWG). We suggest that the IWG decrease is induced by a lessening of the renin angiotensin aldosterone system that could be less stimulated at the end of the dialysis session because of a better‐preserved arterial pressure. The decrease of angiotensin could lessen the feeling of thirst.