bluuebunny/crossref_metadata_2025 huggingface dataset:
Extracorporeal circuit heparinization in selective low density lipoprotein apheresis: Changes in patient hemostasis and low molecular weight heparin benefit
Authors: Lorenzini Jean‐Louis , Dutrillaux Fabienne , Mousson Christiane , Lassale Bernard , Maynadié Marc , Rifle Gérard
Published: February 2007

Treatment by low density lipoprotein (LDL) apheresis using dextran sulfate columns (DSC) leads to hemostasis alterations with prolonged activated partial thromboplastin time (APTT) of more than 120 seconds. In order to explain this hypocoagulability, we studied hemostasis parameters both in patients and in the extracorporeal circulation (ECC). Hemostasis changes are first related to unfractionated heparin (UFH)—needed to avoid circuit coagulation—which leads to high residual heparinemia in the patient (more than 3 times the recommended level for therapeutic use). Second, the hypocoagulability is induced by a coagulation factor decrease (primarily factors V, VIH, and X) mainly due to an adsorption mechanism on dextran sulfate. Studies on samples from column inflow, outflow, and eluate confirm this mechanism. Low molecular weight heparin (LMWH) can be used in LDL apheresis on DSC without major changes in lipid removal or coagulation factors compared to UFH. The benefit of using LMWH is to reduce residual heparinemia into the therapeutic range. © 1993 Wiley‐Liss, Inc.
Hypercoagulable state induced by thrombocytapheresis
Authors: Kobayashi Isao , Hamaoka Satomi , Ozawa Hideyuki , Ihno Masaki , Tamura Kohji , Tanaka Yoshiyuki , Sakamoto Yumi , Nakamura Atsumichi , Ueno Akira
Published: February 2007

The influence of the continuous‐flow automated blood cell separator, Fenwal CS‐3000, on blood coagulation and the fibrinolytic system in blood donors was studied. Blood samples were taken from the collection line of donors undergoing extracorporeal circulation, before and after platelet pheresis. Of the molecular markers, prothrombin fragment‐Fl + 2 (PFI + 2) markedly increased from 0.8 ± 0.3 to 2.9 ± 2.0 nM/ml (P < .004), thrombin antithrombin III complex (TAT) also markedly increased from 2.6 ± 1.3 to 56.0 ± 24.0 μg/L (P < .001), fibrinopeptide A (FPA) increased slightly from 0.8 ± 0.9 to 3.8 ± 4.2 μg/L (P < .05), and α2‐plasmin inhibitor (α2‐PI) decreased slightly from 95 ± 8 to 91 ± 9% (P < .05). In one donor with the highest level of PFI + 2, TAT, FPA, and plasmin inhibitor complex after platelet pheresis, protein C, protein S, C4b‐binding protein, ATIII, plasminogen, α2‐PI, and coagulation factors were decreased. In blood donors undergoing platelet pheresis using the continuous‐flow automated blood cell separator, Fenwal CS‐3000, a hypercoagulable state was observed. Changing the materials of the plastic disposables to a more thromboresistant material may prevent the hypercoagulable state in donors induced by platelet pheresis using the blood cell separator. © 1993 Wiley‐Liss, Inc.
What's new in treatment?
Authors: Collier Ann C.
Published: February 2007

The status of clinical drug trials is reviewed along with how these experimental protocols have influenced treatment for HIV and AIDS. © 1993 Wiley‐Liss, Inc.
New trends in HIV/AIDS epidemiology
Authors: Lafferty William E.
Published: February 2007

World geographic patterns of HIV infection are discussed. Various parameters such as age, route of transmission, exposure, culture, and geographical influences are addressed. Future trends for HIV infection and development of AIDS and associated disorders such as non‐Hodgkin's lymphoma are suggested and strategies are suggested to reduce the impact of this epidemic. © 1993 Wiley‐Liss, Inc.
Complications of therapeutic plasma exchange: A recent assessment
Authors: Couriel Daniel , Weinstein Robert
Published: February 2007

The use of therapeutic plasma exchange, particularly for management of patients with neurological disorders, has steadily increased in our hospital since 1991, thus highlighting the need for continuing quality assurance of these services. We have reviewed the hemapheresis records of all 381 therapeutic plasma exchange procedures performed on a total of 63 patients from January 1991 through December 1992. Patients were referred for therapeutic plasma exchange for the following indications: acute Guillain‐Barre syndrome, 31 patients (49.2%); chronic inflammatory demyelinating polyneuropathy, 15 patients (23.8%); myasthenia gravis, five patients (7.94%); paraproteinemic neuropathy, five patients (7.94%); thrombotic microangiopathies, six patients (9.52%) and Goodpasture syndrome, one patient (1.6%). Overall, 89% of patients were treated for neurological disorders. Complications of plasma exchange were noted during 17% (n = 65) of procedures involving 49% (n = 31) of patients treated. Approximately 91% of complications were classified as mild (55.4%) or moderately severe (35.4%) and did not prevent successful completion of the procedure. These were largely related to use of citrate‐containing anticoagulants and additionally may have reflected the autonomic instability of many of the neuropathy patients. All four (6.15%) severe complications and one of two fatalities were related to the use of central venous access catheters. We conclude that therapeutic plasma exchange can be performed safely with acceptable toxicity caused by mild and moderately severe complications. Major complications may be minimized by careful management of central venous catheters when required for access. © 1994 Wiley‐Liss, Inc.
Effects on feto‐placental markers with plasma exchange in pregnancy
Authors: Gerhardt Robert E. , Koethe John D. , Ntoso K. Adu , Lodge Susan , Schlaff Sheldon , Wolf Charles J.
Published: February 2007

To evaluate changes in feto‐placental markers with plasma exchange in pregnancy, two patients at varying stages of pregnancy referred to a tertiary care hospital and requiring plasma exchange for intercurrent problems were evaluated. Alpha‐fetoprotein, human chorionic gonadotropin, and free estriol were sequentially measured in the patients' plasma and in the fluid removed, thus permitting calculations of permeability rates and clearances. Despite markedly different molecular weights, all three feto‐placental markers had similar permeabilities and clearances. While in both patients maternal levels of alpha‐fetoprotein and human chorionic gonadotropin decreased rapidly with plasma separation and rebounded rapidly to baseline, free estriol responded differently and did not appear to decrease with therapy. Maternal levels of feto‐placental markers only transiently changed with plasma exchange during pregnancy and rapidly returned to baseline with no apparent consequences to the pregnancy. © 1994 Wiley‐Liss, Inc.
Collection efficiency on the fenwal CS3000 when using filgrastim (recombinant methionyl human granulocyte colony‐stimulating factor) as a peripheral blood stem cell mobilization agent
Authors: To L. Bik , Stemmelin German R. , Haylock David N. , Bayly Joanne L. , Thorp Dawn , Rawling Caroline M. , Trimboli Sandra , Juttner Christopher A.
Published: February 2007

The collection efficiency (CE) of the Fenwal CS3000 in collecting peripheral blood stem cells during post‐chemotherapy recovery phase ranges from 58% to 73%. Recently filgrastim (recombinant methionyl human granulocyte colony‐stimulating factor [G‐CSF]) has also been shown to be effective as a mobilization agent although mobilization occurs during elevated and not low normal leukocyte counts. We compared the mononuclear cell (MNC) CE and the myeloid progenitor cell (CFU‐GM) CE among 11 patients with G‐CSF mobilization (33 procedures) and 19 patients during recovery following myelosuppression chemotherapy (93 procedures). Pre‐apheresis leukocyte, neutrophil, MNC, and PB CFU‐GM counts were significantly higher in the G‐CSF group, while the granulocyte percentage in the apheresis products was similar in both groups. Both MNC CE (81.8 ± 4.5% vs. 64 ± 2.4%) and CFU‐GM CE (79.5 ± 10.5% vs. 55.8 ± 3.5%) were higher in the G‐CSF group. Only the pre‐apheresis MNC count showed an independently significant correlation for both CE (P <.001). The higher CE in the G‐CSF group can only be partly explained by a rise in MNC count during apheresis. These data suggest that the blood cell separator works better with leukocytosis, and especially with a higher MNC count. The improvement in CE is another benefit of G‐CSF mobilization over chemotherapy mobilization. © 1994 Wiley‐Liss, Inc.
Goodpasture's syndrome in childhood: Treatment with plasmapheresis and immunosuppression
Authors: McCarthy Leo J. , Cotton Jenny , Danielson Constance , Graves Vicki , Bergstein Jerry
Published: February 2007

Goodpasture's syndrome rarely affects children. Therefore, we present our experience in a young boy whose pulmonary hemorrhage was dramatically resolved by three plasma exchanges. We believe the hemorrhage was caused primarily by acute capillaritis. He received cytoxan and steroids and a series of plasma exchanges which removed/suppressed his anti‐glomerular basement membrane (anti‐GBM) antibody production. However, after a year, his renal function did not return, and he required renal transplantation and continues to do well.
Decrease of thyroid hormones in patients with familial hypercholesterolemia during dextran sulphate low‐density lipoprotein apheresis
Authors: Pintus S. , Pintus P. , Piras C. , Loviselli A. , Muntoni S.
Published: February 2007

Removal of low‐density lipoproteins from plasma by dextran sulfate adsorption (DSA) in FH patients entails a decrease in plasma levels of thyroid hormones (−28.5% and −18.7%, respectively, for T3 and T4). This suggests that FH patients have a greater than normal fraction of thyroid hormones bound to lipoproteins, due to their expanded lipoprotein pool.
Integration of concurrent collection of plasma into a plateletpheresis program
Authors: Burger Scott R. , Thomas Betsy T. , Grishaber Judy E.
Published: February 2007

We have reviewed our initial experience with a program of concurrent collection of plasma (CCP) during plateletpheresis, which was instituted to increase the number of units of fresh frozen plasma produced by our hospital‐based donor service. Sixty percent of eligible donors (1,006 of 1,682) participated in CCP, and 21 donors subsequently dropped out of the program. Of these, only one of four first‐time donors have returned, whereas the majority of established plateletpheresis donors (16 of 17) have continued to donate platelets. Additional plasma was collected at a minimum of 8‐week intervals on the Fenwal CS‐3OOO Plus or COBE Spectra without a change in the requirements for donor testing or the collection procedure. The quality of these platelet products was compared to that of those donated without CCP. There was a small decrease in platelet yield for products with CCP on the CS‐3OOO Plus (mean yield 4.5 × 1011 with CCP versus 4.9 × 1011 without CCP, P < .01). No negative effects were seen on the percentage of products with a minimum yield of 3 × 1011 platelets or on leukocyte contamination. In addition, there was no difference in the rate of adverse donor reactions. During a 12‐month interval, CCP provided 34% (3,798 of 11,266 units) of all fresh frozen plasma for our hospital without additional staff or equipment. The results of this retrospective study suggest that CCP merits further evaluation.
Cellular gene therapy: An overview
Authors: Klein Harvey G.
Published: February 2007

Recombinant DNA technology has provided the tools for gene‐based cellular therapies. The increasing ability to characterize disease in molecular terms affords the scientific rationale for gene therapy, while advances in cell biology, cytokine physiology, and gene delivery have made somatic cell gene therapy feasible. In 1990, the first successful human gene therapy was performed to correct severe combined immunodeficiency resulting from an inherited disorder, adenosine deaminase deficiency. Peripheral blood lymphocytes were used to deliver a gene product as temporary therapy. Today more than a dozen clinical protocols, using a variety of cell types and gene vectors, are in different stages of development. Some promise to be curative. Potential target illnesses include a variety of inherited genetic diseases, as well as such acquired disorders as cancer and AIDS. Although basic problems relating to gene transfer efficiency and expression, assay systems, and quality assurance remain, the technology to collect large numbers of cells, to purify cell subsets, to gene‐modify these cells, and to expand them for human infusion suggest practical new strategies for cellular gene therapy.
Rapid red cell transfusion by Apheresis
Authors: McLeod Bruce C. , Reed Susan , Viernes Ann , Valentino Leonard
Published: February 2007

Packed red cells (RBC) are customarily infused slowly to allow time for re‐equilibration of intravascular volume, but they may be given rapidly for convenience during hemodialysis or partial RBC exchange when blood volume can be adjusted extracorporeally. We describe an apheresis procedure for rapid transfusion of RBC to patients with chronic anemia in which an equivalent volume of recipient plasma is withdrawn as donor RBC are infused. Fifteen such procedures, transfusing 3 to 5 RBC units each, have been performed on nine patients (4 of them outpatients) with either COBE Spectra or COBE 2997. Mean ± SD procedure duration was 1.79 ± .44 hr; patient hemoglobin rose from 7.3 ± 1.5 to 12.± 1.5 g/dl. Comparison to conventional transfusion was possible for nine procedures on six patients in which rapid transfusion required .52 ± .12 vs. 2.70 ± .37 hr per unit (P < .001) and raised hemoglobin by 1.22 ± .30 vs. 88 ± .34 g/dl per unit (P < .02). Pink plasma noted during one procedure was attributable to infusion of an older AS‐1 unit with extensive storage hemolysis. Rapid transfusion was subjectively well tolerated. Immediate post‐procedure systolic blood pressures did not differ significantly from baseline, although one hypertensive patient had headache followed by increased blood pressure 4 hours after a procedure. We conclude that rapid transfusion of RBC is a technically feasible and more time efficient means for RBC transfusion. It is particularly attractive in the outpatient setting, and could also prevent fluid overload associated with RBC transfusion in some volume‐sensitive patients.
Efficacy of peripheral blood stem cell transplantation
Authors: Nademanee Auayporn
Published: February 2007

With the advancement in apheresis technique and collection, the role of peripheral blood stem cell (PBSC) transplantation has emerged. PBSC are now being utilized either alone to reconstitute hematopoiesis following high‐dose myeloablative therapy, or in combination with autologous bone marrow transplantation to enhance hematopoietic recovery, or as supportive therapy to allow dose‐intensity of conventional chemotherapy. The role and efficacy of PBSC transplantation will be reviewed in the article.
Improved red cell quality after erythroplasmapheresis with MCS‐3P
Authors: Matthes G. , Tofote U. , Krause K.‐P. , Pawlow I. , Kucera W. , Lerche D.
Published: February 2007

The cell separator MCS‐3P is an apheresis system offering the flexibility to collect standardized red blood cells, plasma, and/or platelets from one donor. Two different programs were used for the red cell apheresis'RBCP (collection of one unit of red cells and two units of plasma) and RBCPS (one unit of red cells and one unit of plasma). The quality of the red cell concentrates (RCC resuspended in SAG‐Mannitol) during the storage time of 42 days was measured by biochemical (ATP, 2,3‐DPG, pH, free Hb, free potassium, glucose, lactose, p50, hemoglobin derivatives) and Theological (morphological index, filtration/rigidity index) parameters. The donation time with 53 donors was 20 min for 355 ml RCC‐SAGM and 440 ml plasma and 7 min for 335 ml RCC‐SAGM and 239 ml plasma. The donor tolerance was analogous to plateletpheresis or plasmapheresis. Twenty units of the RCC‐SAGM were in‐line filtered within 6 or 24 hours after donation. The results obtained for red blood cell storage are at least as good as with standard collection (free hemoglobin, free potassium, glucose, lactose, hemolysis) or better (ATP, 2,3‐DPG, p50, hemoglobin derivatives, filtration/rigidity index) owing to prevention of collection lesion. All blood preparations were sterile after storage (red cells 42 days, plasma after freezing). The erythroplasmapheresis with MCS‐3P can be especially recommended for application in an autologous blood program because the application of autologous blood donation in hospitals is often limited by the preconditions of component separation. The erythroplasmapheresis data with MCS‐3P are encouraging for the development of a new blood collection methodology.
Paired in vivo and in vitro comparison of apheresis and “recovered” platelet concentrates stored for 5 days
Authors: Turner V. S. , Hawker R. J. , Mitchell S. G. , Mead A. M. Seymour
Published: February 2007

Using a paired study, in vivo and in vitro characteristics of apheresis platelets collected on a cell separator and single‐donor whole‐blood (recovered) platelets via platelet‐rich plasma (PRP) were compared after storage for 5 days in similar plastic containers. Autologous platelets from each of 12 volunteers were labeled with 111Indium after storage and reinjected. There was no significant difference in circulating recovery between platelets prepared by the two methods, and only one of five models of survival showed a significant difference. Hypotonic shock recovery was significantly better in apheresis than recovered platelets (57.0% and 32.4%, respectively), whilst aggregation to ADP at 3.2 μM and 32 μM was significantly higher in recovered than in apheresis platelets (17.0% and 45.2% versus 7.8% and 32.9%, respectively). Lactate dehydrogenase (LDH) content was significantly higher in recovered platelets (143.3 versus 77.1 IU/1011 platelets), but LDH release was similar (15.0% cf. 12.6%). There was no significant difference between the two platelet preparations for platelet concentration, pH, aggregation with the calcium ionophore A23187 or collagen plus epinephrine, or ATP content or release. $bL‐TG release was lower in apheresis platelets. Neither product was consistently better than the other for the parameters tested, but apheresis platelets have the advantage of lower donor exposure to the patient.
Therapeutic cytapheresis: Continuous flow versus intermittent flow apheresis systems
Authors: Burgstaler Edwin A. , Pineda Alvaro A.
Published: February 2007

In this retrospective study, we compared two systems, continuous flow (CF) (COBE Spectra) versus intermittent flow (IF) (Haemonetics V‐50, M‐30), in performance of therapeutic plateletapheresis (TP: N = 49 each) and therapeutic leukapheresis (TL: N = 29 each). Pre‐ and post‐procedure cell reductions, specificity of removal, volumes removed, and incidence of adverse reactions were compared. Standard procedures with minor modifications, starch with IF only, and 180 minutes blood processing time were used. The CF system had a significantly lower percent reduction of platelets during TP at 43 ± 17% than IF at 53 ± 19%. However, no significant difference was found between CF and IF in percent reduction of white blood cells during TL with 49 ± 16% and 42 ± 14%, respectively. The CF system had significantly less hemoglobin reduction (5 ± 4% vs. 19 ± 9%, respectively) and white blood cell reduction (13 ± 15% vs. 27 ± 17%, respectively) for TP than IF and lower (not significant) hemoglobin reduction (9 ± 8% vs. 12.4 ± 8.2%, respectively) as well as platelet reduction (27 ± 18% vs. 35 ± 19%, respectively) for TL. CF also had significantly less volume removed than IF during TP (559 ± 97 vs. 883 ± 304, respectively) and TL (710 ± 134 vs. 1405 ± 421 ml, respectively). Incidence of reactions was lower for CF than IF during TP (8% vs. 10%, respectively) and during TL (14% vs. 21%, respectively). Using our techniques, we found both the CF and IF flow systems were capable of adequately reducing cell counts for TP and TL; however, IF was significantly better in reducing platelet counts during TP. The CF system was more specific in its cell reductions as indicated by lower hemoglobin reductions, WBC reductions (TP), platelet reductions (TL), and volume removed. Reaction incidence was also lower for the CF system.
Defective leukocyte function‐related cryoprecipitable protein in Cryoglobulinemia
Authors: Ohshima T. , Sawada K. , Malchesky P. S. , Tanaka J. , Zborowski M. , Koo A. P. , Cathcart M. K.
Published: February 2007

Cryoprecipitable proteins (CPP), purified from plasmas removed during plasmapheresis treatment of patients with type II and type III cryoglobulinemia (CG), were evaluated in vitro for their effect on normal leukocyte function. CPP reduced normal mononuclear cell blastogenesis and polymorphonuclear cell phagocytosis responses in a dose‐dependent fashion. At the maximum concentration studied, 5,000 (μg/ml, CPP were shown to suppress normal blastogenesis and phagocytosis 30–60% and 50–80% below the albumin control, respectively. A 50% suppression of normal blastogenesis and phagocytosis was observed at 500 p.g/ml for type III CPP. Leukocyte functions in CG patients were evaluated and compared to those of healthy controls. Blastogenesis and phagocytosis were significantly inhibited in CG patients. These studies suggest that CG patients have defective leukocyte function and that CPP have suppressive effects on normal leukocyte function. Our studies suggest that removal of CPP in CG patients may prove beneficial not only in reducing typical symptoms of CG but also in reducing the potencial inhibitory effects of CPP on leukocyte function.
Interferon inhibitor factor predicting success of plasmapheresis in patients with multiple sclerosis
Authors: Medenica Rajko D. , Mukerjee Sonjoy , Huschart Teresa , Corbitt Wendy
Published: February 2007

Interferons (IFN) are biological molecules with antiviral, antiproliferative, and immunomodulatory actions. Plasmapheresis (PP) combined with IFN therapy in 24 multiple sclerosis (MS) patients was associated with a rapid increase in detectable IFN levels. We describe the presence of a detectable factor in the serum of MS patients which decreases the efficacy of IFN therapy in these patients. We call this factor “interferon inhibitor factor” (IIF). Standard IFN assay indicates inhibition of WISH cell protection by IFN owing to the presence of IIF in patient's serum. Similar results were also obtained with human fibroblast and human leukocyte IFNs. The best results were obtained with an IFN mixture; results with 1:20 diluted patient's sera showed elevation of 120% greater than 1:10 dilution. With 1:40 dilution, an elevation of 1,041% was noticed. The IIF from patient sera collected during PP was purified and characterized. Native gel electrophoresis of IIF indicates a single protein band; further analysis on SDS gels indicates two bands at the 200 and 21‐kD range. ELISA failed to reveal the presence of any anti‐IFN antibodies. This study demonstrates the presence of IIF in MS patients' sera which are removed from the circulation by PP. Removal of IIF from circulation was associated with increased IFN levels and clinical improvement as measured by Kurtzke's disability status scale (KDSS).
HELLP syndrome: Laboratory parameters and clinical course in four patients treated with plasma exchange
Authors: Julius C. J. , Dunn Z. L. , Blazina J. F.
Published: February 2007

We report our apheresis department's experience with four patients with HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome. The average age of the patients was 23.25 years (range 19‐27). Three were in their second pregnancy while one was a primigravida. All had symptoms of pre‐eclampsia prior to delivery. All experienced the syndrome postpartum. Plasma exchange was instituted an average of 3.25 days postpartum (range 1.08‐7.33 days). All underwent plasmapheresis with fresh frozen plasma replacement. The average number of plasma exchange treatments was four (range 1‐8). The first laboratory parameter to reach its peak/nadir was the aspartate aminotransferase (AST), followed by the lactate dehydrogenase (LDH) enzyme level, followed by the hemoglobin (HGB) level, and, finally, the platelet count (PLT). The AST was the first parameter to peak and the first to normalize. In the three cases in which more than one plasmapheresis procedure was performed, plasmapheresis was required for an average of 98 hours (range 39‐206 hours) after a normal AST level was obtained in order to achieve a self‐sustaining platelet count of = 100 × 109/L. No additional exchanges were required to maintain the PLT once a PLT of over 100 × 109/ L was attained. The laboratory values normalized in the following order: AST, HGB, PLT, and LDH. Three patients were discharged anemic. One was discharged with a normal LDH level. By our experience, awaiting normal LDH levels as an indicator for cessation of plasma exchange therapy would mean subjecting the patients to many unnecessary procedures. Although AST elevation reflects the peak of disease activity, a platelet count of over 100 × 109/L is more reflective of adequate reversal of the disease process.
Large‐bore central venous catheters for the collection of peripheral blood stem cells
Authors: Hahn Uwe , Goldschmidt Hartmut , Salwender Hans , Haas Rainer , Hunstein Werner
Published: February 2007

In order to establish a peripheral blood stem cell graft, repeated aphereses are necessary in the majority of patients. Each apheresis requires withdrawal and reinfusion of blood with high flow rates. To guarantee these flow rates, large‐bore catheters are needed for central venous access. Subcutaneously tunneled silicone catheters (Hickman) caused venous thrombosis in 10–40% of the patients. We therefore used polyurethane large‐bore catheters only for the time of peripheral blood stem cells (PBSC) collection. Via a Seldinger guidewire following delineation of the right (160 patients) or left (23 patients) internal jugular vein by ultrasound, 183 apheresis catheters have been inserted when the white blood cell count was >1.0 × 109/L and a measurable population of CD34+ cells was detected by fluorescence‐activated cell sorter analysis. The median flow rate was 70 ml/min (range 50–80 ml/min). We observed the following complications: puncture of the carotid artery in 2%, pneumothorax in 0.5%, local infection in 3%, and catheter‐related septicemia in only 2% of the patients. At the time of the removal of the catheters, we detected thrombosis of the internal jugular vein in 5% of the patients by ultrasound. The collection of PBSC with short‐term, large‐bore catheters is effective and is associated with a low incidence of infection and thrombosis.
Research and development in the blood bank: Efforts of a hospital donor center to improve efficiency of in‐line leukocyte reduction filters for automated plateletpheresis
Authors: Drew Mary Jo , Hodges Justin
Published: February 2007

In‐line leukocyte reduction filters (LRF) are available for use with an automated plateletpheresis (PPH) system. Initially, 62% of PPH units produced with such a filter (LRF6, N = 29) had postfiltration (POF) white blood cell (WBC) counts <5 × 106, with a mean POF WBC of 42 × 106. In an attempt to decrease POF WBCs, PPH were rested 30 to 60 minutes before filtration with LRF6. A new, larger‐volume LRF (LRF10) was also assessed for its efficiency of leukodepletion. A total of 625 PPH, 490 filtered with LRF6 and 135 with LRF10, were evaluated using prefiltration (PRF) and POF samples. Mean prefiltration WBC loads averaged 80 × 106 (range, 60–88 × 106) using seven combinations of filters, collection software, and PRF rest periods. Ninety‐three percent of PPH units rested prior to filtration with LRF6 (N = 237) had <5 × 106 WBC POF, with a mean of 5 × 106 WBC POF. All PPH units filtered with LRF10 (N = 135), whether rested or not, had <5 × 106 WBC POF, with a mean WBC count of 0.2 × 106 POF. Mean platelet (PLT) yields POF ranged from 3.1 to 3.4 × 1011. A PRF rest decreased mean POF WBC counts in products filtered with LRF6. The LRF10 consistently produced PPH with <5 × 106 WBC POF. Blood centers must thoroughly validate equipment utilized in the production of blood components.
Leukoreduced platelet apheresis production with a modified COBE spectra collection protocol
Authors: Kuriyan Mercy , Opalka Andrew
Published: February 2007

A platelet apheresis product or single donor platelet (SDP) with a white blood cell content of 5 × 106 or below is considered optimal for transfusion. We modified the COBE spectra platelet collection protocol as follows: increased AC infusion rate of 1.1 ml/min/LTBV, setting the inlet:AC ratio configuration at high, and maintained the inlet flow rate of this setting with a maximum of 80 ml/min. The collection time varied with single dose or double dose production. The aim was to consistently obtain a platelet yield above 3 × 1011 and 2 WBC content less than 5 × 106. The results were tabulated on 64 donations. The platelet yield was >3 × 1011 for 59 donations with a mean of 4.89, median of 4.72, and a range of 3.02 to 8.14; and <3 × 1011 for 5 donations with a mean of 2.74, median of 2.84, and a range of 2.14 to 2.96. The WBC content was <5 × 106 for 60 donations with a mean of 0.52, median of 0.20, and a range of 0.06 to 0.71; and >5 × 106 for 4 donations with a mean of 59.9, a median of 48.9, and a range of 8.12 to 62.

We conclude that 93.8% of the donations yielded a SDP that met or exceeded leukoreduction standards.
Peripheral blood stem cell collection in a patient with chronic myelogenous leukemia and a high circulating nucleated red cell fraction
Authors: Lee Jong‐Hoon , Miraglia Charles C. , Grosh William W. , Mintz Paul D.
Published: February 2007

A high level of circulating nucleated red blood cells (NRBC) in patients with chronic myeloproliferative syndromes could potentially complicate peripheral blood stem cell (PSC) collection. The mononuclear NRBC might comprise a significant fraction of the total mononuclear cells in the final product. We report a successful PSC collection in a patient with more NRBC than WBC in the peripheral blood. A 27‐year‐old man with chronic myelogenous leukemia underwent eight PSC collection procedures, seven using the Cobe Spectra (Spectra) and one using the Fenwal CS3000 Plus (CS). PSC product manipulations to remove NRBC were unnecessary. As assessed by post‐collection NRBC:WBC ratio as a percent of the initial ratio, Spectra selectively harvested mononuclear leukocytes over NRBC. The collected products had a mean NRBC:WBC ratio that was 3.4% of the peripheral blood ratio. Adequate numbers of mononuclear leukocytes were collected with less than 6% NRBC contamination. The single CS procedure resulted in a comparable NRBC reduction efficiency as the Spectra. We conclude that PSC harvest using automated blood cell separators from patients with a high level of circulating NRBC may result in a product with an acceptable number of NRBC.
Clinical perspectives of granulocyte transfusions: Efficacy to date
Authors: Strauss Ronald G.
Published: February 2007

The literature pertaining to the use of granulocyte transfusions as treatment for progressive bacterial, yeast, and fungal infections in severely neutropenic patients is reviewed. Efficacy in treating bacterial infections that are unresponsive to antimicrobial therapy is well established—especially if bone marrow failure does not recover rapidly and neutropenia is persistent. The role of therapeutic granulocyte transfusions for yeast and fungal infections has potential merit, but current data are incomplete and findings are inconsistent. The possibility of greater success has been raised by use of recombinant granulocyte colony stimulating factor to greatly increase the yield of neutrophils collected from normal donors.
Autologous peripheral blood progenitor cell transplantation
Authors: Anderson Kenneth C.
Published: February 2007

Harvesting of autologous peripheral blood stem cells (PBSCs) has been facilitated by using currently available, efficient apheresis technology at the time of rebound from chemotherapy while patients are receiving recombinant growth factors, i.e., granulocyte (G) or granulocyte‐macrophage (GM) colony stimulating factor (CSF). Ideally pheresis should be done before patients have had extensive stem cell toxins, i.e., alkylating agents or nitrosoureas. This strategy has facilitated the use of high dose chemoradiotherapy given as a single regimen or in a divided dose for patients with solid tumors or hematologic malignancies and results in more rapid engraftment than bone marrow transplantation (BMT). Although mere are no assays which measure repopulating stem cells, enumeration of CD34+ cells within PBSCs is a direct and rapid assay which provides an index of both early and late long‐term reconstitutive capacity, since it correlates with colony‐forming unit (CFU)‐GMs, as well as pre‐progenitor or delta assays and long‐term culture‐initiating cells (LTC‐IC). A threshold of ≥2 × 106 CD34+ cells/kg recipient body weight has been reported to be required for engraftment, but may vary depending upon the clinical setting. Strategies for mobilization of normal PBSCs also increase tumor cell contamination within PB in the setting of both hematologic malignancies and solid tumors, but the significance of these tumor cells in terms of patient outcome is unclear. Recently isolation of CD34+ cells from PBSCs has been done using magnetic beads or immunoabsorption on columns or rigid plates in order to enrich for normal hematopoietic progenitors and potentially decrease tumor cell contamination. As for other cellular blood components, standards have been developed to assure efficient collection and processing, thawing, and reinfusion, and to maintain optimal PBPC viability. Finally, future directions of clinical research include expansion of hematopoietic progenitor cells ex vivo; use of umbilical cord or placenta as rich sources of progenitor cells; syngeneic hematopoietic stem cell transplantation; related and unrelated allogeneic hematopoietic stem cell transplantation; treatment of infections, i.e., Epstein Barr virus, or tumor relapse after allogeneic BMT using donor PBSC infusions; and gene therapy approaches.
Balancing work and family: a field study of multi‐dimensional, multi‐role work‐family conflict
Authors: Premeaux Sonya F. , Adkins Cheryl L. , Mossholder Kevin W.
Published: February 2007

Little is known about the effectiveness of family‐friendly policies (FFPs) in reducing interrole conflicts involving work and family. The present study examined the influence of FFPs, work‐family culture, and family characteristics on salient job outcomes, and multiple dimensions of work‐family conflict (WFC) and family‐work conflict (FWC). Results from a survey of 564 workers, indicate that FFPs exert minimal effects on felt conflict, and that a positive work‐family culture and family support may be more instrumental in helping employees balance work and home roles. Findings also suggest that sources of conflict varied among workers, as did the mechanisms used to address WFC and FWC. This study underscores the importance of examining WFC as a multi‐dimensional phenomenon affecting employees in a variety of family structures, as well as considering the impact of FFPs in conjunction with work‐family culture. Copyright © 2007 John Wiley & Sons, Ltd.
Leader–member social exchange (LMSX): development and validation of a scale
Authors: Bernerth Jeremy B. , Armenakis Achilles A. , Feild Hubert S. , Giles William F. , Walker H. Jack
Published: February 2007

In the last 10 years, research devoted to the construct of leader–member exchange (LMX) has increasingly relied on the tenets of social exchange as a theoretical foundation to propose and test relationships between supervisor‐subordinate dyads and variables of significant consequence. Despite the theory underpinning such relationships, researchers continue to measure LMX with scales developed to assess vertical dyad linkage (VDL), not social exchange. To address this concern, we investigated the content validity of LMX7 (the most widely cited measure of LMX) and LMX‐MDM (a popular multidimensional measure of LMX). Findings from content validity assessments by 25 LMX experts revealed LMX7 and LMX‐MDM items are not representative of the construct of social exchange. As such, we undertook a series of studies to develop a new scale we label, leader–member social exchange (LMSX). Results indicate LMSX is able to assess different, as well as the same, components of the supervisor–subordinate relationship as previous scales while being more theoretically consistent with the notion of social exchange. Copyright © 2007 John Wiley & Sons, Ltd.
Ice‐borne prehistoric finds in the Swiss Alps reflect Holocene glacier fluctuations
Authors: Grosjean Martin , Suter Peter J. , Trachsel Mathias , Wanner Heinz
Published: February 2007

During the hot summer of 2003, reduction of an ice field in the Swiss Alps (Schnidejoch) uncovered spectacular archaeological hunting gear, fur, leather and woollen clothing and tools from four distinct windows of time: Neolithic Age (4900 to 4450 cal. yr BP), early Bronze Age (4100–3650 cal. yr BP), Roman Age (1st–3rd century AD), and Medieval times (8–9th century AD and 14–15th century AD). Transalpine routes connecting northern Italy with the northern Alps during these slots is consistent with late Holocene maximum glacier retreat. The age cohorts of the artefacts are separated which is indicative of glacier advances when the route was difficult and not used for transit. The preservation of Neolithic leather indicates permanent ice cover at that site from ca. 4900 cal. yr BP until AD 2003, implying that the ice cover was smaller in 2003 than at any time during the last 5000 years. Current glacier retreat is unprecedented since at least that time. This is highly significant regarding the interpretation of the recent warming and the rapid loss of ice in the Alps. Copyright © 2007 John Wiley & Sons, Ltd.
Microwave‐Assisted Esterification of Methacrylic Acid and Polymer‐Analogous Esterification of Poly[ethylene‐co‐(acrylic acid)] with Dissimilar Phenols
Authors: Bezdushna Ella , Ritter Helmut
Published: February 2007

Phenyl methacrylate and p‐tolyl methacrylate were synthesized by starting directly from methacrylic acid and the corresponding phenols. Polymer‐analogous esterification on poly[ethylene‐co‐(acrylic acid)] (PEAA) was performed with phenol, p‐methoxyphenol, and 2,4,6‐trimethylphenol. The synthesized compounds were characterized by FT‐IR and 1H NMR measurements. The esterification reactions were performed under solvent‐free conditions using an acid catalyst under microwave irradiation and in an oil‐bath, for comparison. It was shown that MW irradiation effectively promotes the esterification especially on the polymeric system. Differential scanning calorimetry was employed to study the thermal behavior of modified and unmodified PEAA. One pot reaction and reaction time within minutes are the main advantages of the MW method.

magnified image
Microwave‐Assisted Homogeneous Polymerizations in Water‐Soluble Ionic Liquids: An Alternative and Green Approach for Polymer Synthesis
Authors: Guerrero‐Sanchez Carlos , Lobert Matthias , Hoogenboom Richard , Schubert Ulrich S.
Published: February 2007

Water‐soluble ionic liquids (IL) were used as reaction media to perform homogeneous polymerizations under microwave irradiation. The investigated reaction systems include the free radical polymerization of methyl methacrylate and the cationic ring opening polymerizations of 2‐phenyl‐2‐oxazoline and 2‐(m‐difluorophenyl)‐2‐oxazoline. The incorporation of ILs into the polymerizations showed a more efficient heating profile of the reaction mixtures under microwave irradiation in comparison to the cases without ILs. Moreover, a convenient approach for the polymer isolation and recovery of the ILs for further polymerizations is demonstrated taking advantage of the water solubility of the investigated ILs. This synthetic approach is an alternative, efficient, and green method for the manufacture of hydrophobic polymers which may allow depletion of the emission of volatile organic compounds into the environment and for energy savings.

magnified image
Preparation of Novel Metallic and Bimetallic Cross‐Linked Poly(vinyl alcohol) Nanocomposites under Microwave Irradiation
Authors: Nadagouda Mallikarjuna N. , Varma Rajender S.
Published: February 2007

A facile method utilizing microwave irradiation is described that accomplishes the cross‐linking reaction of PVA with metallic and bimetallic systems. Nanocomposites of PVA‐cross‐linked metallic systems such as Pt, Cu, and In and bimetallic systems such as Pt‐In, Ag‐Pt, Pt‐Fe, Cu‐Pd, Pt‐Pd and Pd‐Fe were prepared expeditiously by reacting the respective metal salts with 3 wt.‐% PVA under microwave irradiation, maintaining the temperature at 100 °C, a radical improvement over the methods for preparing cross‐linked PVA described in the literature. The general preparative procedure is versatile and provides a simple route to manufacturing useful metallic and bimetallic nanocomposites with various shapes, such as nanospheres, nanodendrites and nanocubes.

magnified image
Scale‐Up of Microwave‐Assisted Polymerizations in Continuous‐Flow Mode: Cationic Ring‐Opening Polymerization of 2‐Ethyl‐2‐oxazoline
Authors: Paulus Renzo M. , Erdmenger Tina , Becer C. Remzi , Hoogenboom Richard , Schubert Ulrich S.
Published: February 2007

Microwave‐assisted polymerizations is a growing field of interest because the use of microwave irradiation instead of thermal heating was demonstrated to result in faster, cleaner, and higher yielding reactions. To overcome the one‐at‐a‐time nature of preparing polymerizations in single microwave vials and the possible scale‐up method for microwave‐assisted polymerizations, the use of continuous‐flow reactions under microwave irradiation seems to be ideal. In this contribution, we report for the first time the use of different continuous‐flow microwave reactors for polymerizations, using the cationic ring‐opening polymerizations of 2‐ethyl‐2‐oxazoline as a model system. In addition, the observed broader molecular‐weight distributions were correlated to residence time distributions of the continuous‐flow reactors that were determined using methyl orange as the flow marker.

magnified image
Water Diffusion in Glassy Polymers and their Silica Hybrids: an Analysis of State of Water Molecules and of the Effect of Tensile Stress
Authors: Larobina Domenico , Lavorgna Marino , Mensitieri Giuseppe , Musto Pellegrino , Vautrin Alain
Published: February 2007

In‐situ, time‐resolved FTIR spectroscopy along with gravimetric analysis have been used to investigate water sorption and transport in several glassy polymeric matrices, characterized by different levels of interaction with water, as well as on polymer‐silica hybrids. This technique has also been coupled to a dynamical‐mechanical analyser to gather information on the water sorption kinetics and thermodynamics in a polymer sample submitted to stretching deformation and load. Results have been modelled by coupling the mass balance and momentum balance, using a theoretical approach developed for elastic matrices and low sorbed amounts by Larché and Cahn.
Air‐Coupled Ultrasonic Cure Monitoring of Unsaturated Polyester Resins
Authors: Lionetto Francesca , Tarzia Antonella , Coluccia Miriam , Maffezzoli Alfonso
Published: February 2007

Air‐coupled ultrasound in one‐side transmission mode has been applied to monitor the curing process of an unsaturated polyester resin, commonly used as a matrix in glass reinforced composites. The evolution of the resin mechanical properties during cure has been measured from the variation of longitudinal velocity. The technique has demonstrated to be a very powerful tool for detecting the structural changes occurring at gelation and vitrification. The no‐contact ultrasonic results have been compared with those obtained using conventional contact ultrasonic measurements, characterized by direct coupling between the transducer and the resin, and with the rheological measurements. The good agreement among the results of the different techniques demonstrates the reliability of air‐coupled ultrasound in monitoring the changes of viscoelastic properties occurring during the cure of thermosetting polymers. A further advantage of the proposed one‐side ultrasonic technique is the absence of physical contact between the transducers and the sample, which is relevant during composite manufacturing, where probe contact could adversely affect the part quality or access from both sides is not practicable. No‐contact ultrasonic cure monitoring is suitable for both stationary and moving liquid or solid samples in several process conditions such as moulding, filament winding, etc., opening the way to new applications of ultrasound in the composite industry.
Rheological and Structure Investigation of Melt Mixed Multi‐Walled Carbon Nanotube/PE Composites
Authors: Nobile Maria R. , Simon George P. , Valentino Olga , Morcom Melanie
Published: February 2007

In this study a series of melt mixed multi‐walled carbon nanotube (MWNT)/Polyethylene composites with several carbon nanotube (CNTs) concentrations were investigated. A good dispersion of the nanotubes in the matrix was seen using scanning electron microscopy. Melt rheological measurements in dynamic mode were used to estimate the percolation state of the CNTs within the polymer and to provide information about the structure of the CNT/polymer composites. The effect of nanotubes on the non‐isothermal crystallization behaviour of the nanocomposites was also studied by differential scanning calorimetry.
Silica‐graft‐polyamidoamine Hybrid Materials: Effect of Constraints on the Polymer Mobility
Authors: Sartore Luciana , Penco Maurizio , Sciucca Stefania Della , D'Amore Alberto
Published: February 2007

Organic‐inorganic hybrid materials with excellent heavy metal ions chelating properties are synthesized by covalent bonding of multifunctional polymers of polyamidoamine (PAA) type onto silica. Two series of polyamidoamine‐silica hybrid materials differing in the PAA chemical structure are prepared and their thermal properties are investigated. Differential Scanning Calorimetry (DSC) is used to study the effects of chain immobilization and ion chelation on the glass‐transition temperature (Tg) of the polymers. The Tg of PAA‐hybrid materials is elevated with respect to ungrafted PAAs, but when the linear and the corresponding hybrid PAAs are in the complex form with metal ions such as Cu2+ and Co2+, the materials arrive to the decomposition temperature and no Tg is detected. To highlight the effect of metal ion on the molecular mobility of these systems, an oligomeric plasticizer is added. The behaviour in the Tg region is analyzed and discussed in term of Tool‐Narayanaswamy‐Moynihan (TNM) model. In particular the apparent activation energy (Δh*) is used to discuss overall segmental co‐operativity in order to better understand the effect of complex formation on structural mobility.