bluuebunny/crossref_metadata_2025_split huggingface dataset:
Contrasting metamorphic histories of lenses of high‐pressure rocks and host migmatites with a flat orogenic fabric (Bohemian Massif, Czech Republic): a result of tectonic mixing within horizontal crustal flow?
Authors: ŠTÍPSKÁ P. , SCHULMANN K. , POWELL R. 
Published: June 2008

AbstractMigmatites with sub‐horizontal fabrics at the eastern margin of the Variscan orogenic root in the Bohemian Massif host lenses of eclogite, kyanite‐K‐feldspar granulite and marble within a matrix of migmatitic paragneiss and amphibolite. Petrological study and pseudosection modelling have been used to establish whether the whole area experienced terrane‐wide exhumation of lower orogenic crust, or whether smaller portions of higher‐pressure lower crust were combined with a lower‐pressure matrix. Kyanite‐K‐feldspar granulite shows peak conditions of 16.5 kbar and 850 °C with no clear indications of prograde path, whereas in the eclogite the prograde path indicates burial from 10 kbar and 700 °C to a peak of 18 kbar and 800 °C. Two contrasting prograde paths are identified within the host migmatitic paragneiss. The first path is inferred from the presence of staurolite and kyanite inclusions in garnet that contains preserved prograde zoning that indicates burial with simultaneous heating to 11 kbar and 800 °C. The second path is inferred from garnet overgrowths of a flat foliation defined by sillimanite and biotite. Garnet growth in such an assemblage is possible only if the sample is heated at 7–8 kbar to around 700–840 °C. Decompression is associated with strong structural reworking in the flat fabric that involves growth of sillimanite in paragneiss and kyanite‐K‐feldspar granulite at 7–10 kbar and 750–850 °C. The contrasting prograde metamorphic histories indicate that kilometre‐scale portions of high‐pressure lower orogenic crust were exhumed to middle crustal levels, dismembered and mixed with a middle crustal migmatite matrix, with the simultaneous development of a flat foliation. The contrasting P–T paths with different pressure peaks show that tectonic models explaining high‐pressure boudins in such a fabric cannot be the result of heterogeneous retrogression during ductile rebound of the whole orogenic root. The P–T paths are compatible with a model of heterogeneous vertical extrusion of lower crust into middle crust, followed by sub‐horizontal flow.
The role of heterogeneous strain in the development and preservation of a polymetamorphic record in high‐P granulites, western Canadian Shield
Authors: MAHAN K. H. , GONCALVES P. , FLOWERS R. , WILLIAMS M. L. , HOFFMAN‐SETKA D. 
Published: June 2008

AbstractMafic rocks in the Chipman domain of the Athabasca granulite terrane, western Canadian Shield, provide the first well‐documented record of two distinct high‐P granulite facies events in the same domain in this region. Textural relations and the results of petrological modelling (NCFMASHT system) of mafic granulites are interpreted in terms of a three‐stage tectonometamorphic history. Stage 1 involved development of the assemblage Grt + Cpx + Qtz ± Pl (M1) from a primary Opx‐bearing igneous precursor at conditions of 1.3 GPa, 850–900 °C. Field and microstructural observations suggest that M1 developed synchronously with an early S1 gneissic fabric. Stage 2 is characterized by heterogeneous deformation (D2) and synkinematic partial retrogression of the peak assemblage to an amphibole‐bearing assemblage (M2). Stage 3 involved a third phase of deformation and a return to granulite facies conditions marked by the prograde breakdown of amphibole (Amph2) to produce matrix garnet (Grt3a) and the coronitic assemblage Cpx3b + Opx3b + Ilm3b + Pl3b (M3b) at 1.0 GPa, 800–900 °C. M1 and M3b are correlated with 2.55 and 1.9 Ga metamorphic generations of zircon, respectively, which were dated in a separate study. Heterogeneous strain played a crucial role in both the development and preservation of these rare examples of multiple granulite facies events within single samples. Without this fortuitous set of circumstances, the apparent reaction history could have incorrectly led to an interpretation involving a single‐cycle high‐grade event. The detailed P–T–t–D history constructed for these rocks provides the best evidence to date that much of the east Lake Athabasca region experienced long‐term lower crustal residence from 2.55 to 1.9 Ga, and thus the region represents a rare window into the reactivation and ultimate stabilization processes of cratonic lithosphere.
ASDIN Clinical Case Focus: Timing of Secondary Arteriovenous Fistula Creation Avoids Tunneled Catheter Placement
Authors: Vachharajani Tushar J. , Atray Naveen K. , Gill Sarjit , Zibari Gazi , Abreo Kenneth D. 
Published: June 2008

AbstractThe concept of secondary arteriovenous fistula, though not novel, is seldom practiced for lack of initiative or hesitancy in deciding the appropriate timing to abandon the existing access. We report a case illustrating the benefits of implementing the strategy in an elderly diabetic dialysis patient, successfully avoiding a tunneled cuffed catheter placement.
Is Basilic Vein Transposition a Real Alternative to an Arteriovenous Bypass Graft? A Prospective Study
Authors: Chemla Eric S. , Morsy Mohamed A. 
Published: June 2008

AbstractBasilic vein transpositions (BVTs) are considered to be superior to arteriovenous bypass grafts (AVGs). However, for the most part studies comparing BVTs to AVGs have been retrospective in design and without a set follow‐up protocol. In this analysis, data were prospectively collected from patients with either a BVT or a brachio‐axillary AVG. When all other native options were exhausted a BVT was performed if the vein had a diameter of 3 mm. All patients had bimonthly measurements of access inflow and recirculation using ultrasound dilution and were followed up for 2 years. Of 76 patients, 34 had a BVT and 42 an AVG (p > 0.05). BVT group: 12 were male, 22 female, the mean age was 62 and 26% were diabetic. AVG group: 22 were male, 20 female, the mean age was 57 and 56% were diabetic. The maturation delay was higher in the BVT group (6 weeks vs. 2 weeks). For the BVT and AVG groups, at 6, 12 and 24 months, respectively, primary patency was 90% vs. 76% (p < 0.05), 73% vs. 61% and 69% vs. 54% (p > 0.05). Assisted primary patency was 100% vs. 90% (p = 0.1201), 96% vs. 56% and 74% vs. 40% (p < 0.001). Secondary patency was 100% vs. 83%, 93% vs. 70% (p < 0.025) and 85% vs. 62% (p < 0.01). In the BVT group, 18 patients had 32 interventions for a total cost of $127,800, while in the AVG group, 27 patients had 54 interventions for a total cost of $227,300. This is the first prospective study to confirm that BVTs were cost effective and associated with better outcomes when compared with AVGs.
A Comparison of Transposed Brachiobasilic Fistulae with Nontransposed Fistulae and Grafts in the Fistula First Era
Authors: Pflederer Timothy A. , Kwok Sophie , Ketel Beverly L. , Pilgram Tom 
Published: June 2008

AbstractThis retrospective study compares outcomes of transposed brachiobasilic fistulae (avf), nontransposed avf, and grafts (avg). There were 161 (21%) transposed avf, 321 (42%) nontransposed avf, and 285 (37%) avg placed and followed over a 3‐year period. Of the nontransposed avf, 203 (63%) were forearm radiocephalic avf and 118 (37%) were upper arm brachiocephalic avf. Grafts were able to be used in shorter time than avf and had a lower primary failure rate. However, avg had a significantly higher infection rate (0.23/patient/year vs. 0.07/patient/year) and required more procedures over the life of the access than avf (2.90/patient/year vs. 0.51/patient/year). Despite a higher primary failure rate, avf had better overall patency. Among nontransposed avf, brachiocephalic avf had significantly better primary patency than radiocephalic avf (p < 0.0001). Transposed avf had better cumulative patency than either nontransposed avf or grafts (p < 0.0001). Cumulative patency was best for transposed avf, intermediate for brachiocephalic avf, and worst with radiocephalic avf and avg. There was no difference in cumulative patency between radiocephalic avf and grafts (p = 0.5601). This analysis supports the current recommendation to prefer transposed avf over avg. In addition, the data suggest that both nontransposed brachiocephalic avf and transposed brachiobasilic avf outcomes may be superior to radiocephalic fistulae.
Efficacy in reducing potassium load in irradiated red cell bags with a potassium adsorption filter
Authors: Cid Joan , Ramiro Laia , Bertran Sílvia , Martínez Núria , Claparols Montse , Maymó Rosa Ma , Puig Lluís , Pla Ramon Pau 
Published: June 2008

BACKGROUND: The transfusion of red cell (RBC) bags with high amounts of potassium (K+) causes concern about an increased risk of cardiac arrest because of transient hyperkalemia. To prevent K+ overload, a K+ adsorption filter (PAF) is available for use at bedside. The aim of the present study was to analyze the efficacy in reducing K+ load in irradiated RBC bags with this PAF.STUDY DESIGN AND METHODS: Whole‐blood (WB) bags were collected from volunteer donors on Day 0. RBC bags were prepared from WB bags on Day +1 and stored at 2 to 6°C. RBC bags were irradiated on Day +14 and filtered with the PAF on Day +28, according to the manufacturers' instructions. The plasma electrolyte levels (Na+, K+, Cl‐, Ca2+, and Mg2+) were measured at the different points during storage.RESULTS: Twelve RBC bags were prepared with a final volume of 274 ± 15 mL. On Day +28, the volume of RBC bags was 257 ± 15 mL, and the PAF was used at a flow rate of 4 ± 0.7 mL per minute. K+ level after RBC bag preparation was 1.28 ± 0.59 mmol per L. The K+ level was 60.6 ± 2.68 mmol per L on Day +28, just before filtration with the PAF. After filtration, the level of K+ was 3.42 ± 2.91 mmol per L.CONCLUSION: This study has shown a high efficacy in reducing potassium load in irradiated RBC bags with the use of the PAF.
A novel immunosuppressive pathway involving peroxynitrate‐mediated nitration of platelet antigens within antigen‐presenting cells
Authors: Semple John W. , Speck Edwin R. , Fabron Jr Antonio , Kim Rukhsana Aslam Michael , Freedman John 
Published: June 2008

BACKGROUND: Studies have demonstrated that immunity against platelet (PLT) transfusions is dependent on recipient antigen‐presenting cells (APCs) and their ability to produce nitric oxide (NO). To further analyze this, we focused on NO's major metabolite peroxynitrite (ONOO‐) and its ability to affect PLT immunity.STUDY DESIGN AND METHODS: To address how NO and its major metabolite may mediate PLT immunity, GP91PHOX knockout (KO) mice that lack the ability to produce the ONOO‐ were transfused weekly with allogeneic BALB/c PLTs, and donor antibody development was analyzed.RESULTS: Compared with controls, GP91PHOX KO mice developed significantly (p < 0.0001) higher‐titered immunoglobulin G (IgG) donor antibodies by two transfusions, and this immune response could be inhibited by treating the recipient mice with aminoguanidine, a relatively selective inhibitor of inducible nitric oxide synthase. In vitro nitration of PLTs did not alter PLT antibody binding but significantly inhibited the transfused PLT's ability to stimulate IgG immunity in either wild‐type or KO mice. The lack of nitrated PLT immunity correlated with an inability of APCs to mediate phagocytosis of nitrated PLTs. The lack of nitrated PLT immunity could only be restored when normal PLTs were mixed with the nitrated PLTs and transfused.CONCLUSION: The results identify a dual role for NO metabolism within APCs that significantly modulates PLT immunity; nitration of PLT antigens leads to lack of immunity due to an inability of APCs to move PLT antigens intracellularly whereas there exists an NO‐dependent pathway that stimulates anti‐PLT immunity.
RBC‐derived vesicles during storage: ultrastructure, protein composition, oxidation, and signaling components
Authors: Kriebardis Anastasios G. , Antonelou Marianna H. , Stamoulis Konstantinos E. , Economou‐Petersen Effrosini , Margaritis Lukas H. , Papassideri Issidora S. 
Published: June 2008

BACKGROUND: Red cells (RBCs) lose membrane in vivo, under certain conditions in vitro, and during the ex vivo storage of whole blood, by releasing vesicles. The vesiculation of the RBCs is a part of the storage lesion. The protein composition of the vesicles generated during storage of banked RBCs has not been studied in detail.STUDY DESIGN AND METHODS: Vesicles were isolated from the plasma of nonleukoreduced RBC units in citrate‐phosphate‐dextrose‐adenine, at eight time points of the storage period and shortly afterward. The degree of vesiculation, ultrastructure, oxidation status, and protein composition of the vesicles were evaluated by means of electron microscopy and immunoblotting. RBCs and ghost membranes were investigated as controls.RESULTS: The total protein content of the vesicle fraction and the size of the vesicles increased but their structural integrity decreased over time. The oxidation index of the vesicles released up to Day 21 of storage was greater than that of the membrane ghosts of the corresponding intact RBCs. The vesicles contain aggregated hemoglobin, band 3, and lipid raft proteins, including flotillins. They also contain Fas, FADD, procaspases 3 and 8, caspase 8 and caspase 3 cleavage products (after the 10th day), CD47 (after the 17th day), and immunoglobulin G.CONCLUSION: These data indicate that the vesicles released during storage of RBCs contain lipid raft proteins and oxidized or reactive signaling components commonly associated with the senescent RBCs. Vesiculation during storage of RBCs may enable the RBC to shed altered or harmful material.
Consequences of transfusion of platelet antibody: a case report and literature review
Authors: Pavenski Katerina , Webert Kathryn E. , Goldman Mindy 
Published: June 2008

BACKGROUND: Passive transfer of platelet (PLT) antibody by blood transfusion can lead to severe thrombocytopenia, bleeding, and an acute transfusion reaction.CASE REPORT: A 49‐year‐old male on warfarin developed thrombocytopenic bleeding within 2 hours of transfusion with a single unit of fresh‐frozen plasma (FFP). The patient's PLT count on admission was 122 × 109 per L. Two hours after transfusion, PLT count has decreased to 5 × 109 per L. The patient's PLT antibody screen by solid‐phase enzyme‐linked immunosorbent assay was negative and his genotype was HPA‐1a/1b. The donor's genotype was HPA‐1b/1b and antibody screen revealed anti‐HPA‐1a. A lookback investigation identified another case of severe thrombocytopenia after FFP infusion 4 years previously.REVIEW OF LITERATURE: A literature review identified 19 cases of passive transfer of PLT antibody that resulted in thrombocytopenia. The PLT nadir of 7 × 109 per L was reached within 6 hours after transfusion with a median time to PLT recovery of 5 days. Transfusion was accompanied by an acute transfusion reaction in 30 percent of recipients. Approximately 75 percent of recipients developed thrombocytopenic bleeding. All cases involved a female donor with a history of pregnancy. High‐plasma‐volume components accounted for the majority of cases while anti‐HPA‐1a was the most frequently implicated antibody.CONCLUSION: Unexplained posttransfusion thrombocytopenia should be investigated to rule out passive transfer of PLT antibodies. Implicated donors should be deferred from subsequent donations. Switching to predominantly male plasma for transfusion may lead to reduction in cases of thrombocytopenia due to passive transfer of PLT antibody. Rational use of blood products may further reduce incidence of this complication.
A Leishmania minicircle DNA footprint assay for sensitive detection and rapid speciation of clinical isolates
Authors: Selvapandiyan Angamuthu , Duncan Robert , Mendez Juan , Kumar Rajesh , Salotra Poonam , Cardo Lisa J. , Nakhasi Hira L. 
Published: June 2008

BACKGROUND: Diversity in clinical outcome, due to different species of Leishmania, and its presence in asymptomatic blood donors in endemic areas warrant development of methods that are sensitive and can rapidly identify infecting species.STUDY DESIGN AND METHODS: The kinetoplast minicircle DNA is known to have heterogeneity in sequence and is present in many thousands of copies in Leishmania. Fluorescence‐based polymerase chain reaction (PCR) was used to amplify minicircle DNA from six Leishmania species from different geographic locations. The sequences were then used to construct a phylogenetic tree. Speciation of 46 blinded parasite clinical isolates from various geographic regions was validated using the assay.RESULTS: Analysis displayed a distinct cluster for each species or strain. Forty‐three of 46 isolates were correctly assigned to the same species identified by isoenzyme electrophoresis. The three untyped isolates were all either new species or samples from a unique geographic region. The minicircles of the three isolates formed new clusters in the tree analysis. Using minicircle DNA as PCR target, the sensitivity of the parasite detection in the spiked blood samples was five parasites per mL.CONCLUSION: Increased sensitivity and speciation without the need for parasite culture will be useful for diagnosis and treatment in clinical settings.
The clinical impact of platelet refractoriness: correlation with bleeding and survival
Authors: Kerkhoffs Jean‐Louis H. , Eikenboom Jeroen C.J. , Van De Watering Leo M.G. , Van Wordragen‐Vlaswinkel Rinie J. , Wijermans Pierre W. , Brand Anneke 
Published: June 2008

BACKGROUND: Despite supportive care with platelet (PLT) transfusions, bleeding complications occur in a substantial number of patients with thrombocytopenia due to cytotoxic therapy. Moreover, refractoriness to PLT transfusions remains a frequently encountered problem. The clinical impact of PLT transfusion failure was investigated in 117 patients, part of a randomized PLT transfusion trial, which excluded patients with HLA and/or HPA alloantibodies.STUDY DESIGN AND METHODS: Between October 2003 and April 2005, a multicenter randomized controlled trial, testing the clinical efficacy of PLTs stored in plasma compared to PLT additive solution (PAS II), was performed. Using multiple regression analysis of observational data of patients randomized in one of the participating centers, the occurrence of PLT transfusion refractoriness was analyzed for a relation with bleeding complications and patient survival.RESULTS: PLT transfusion failure occurred at least once in 49.6 percent of the patients. Mild to moderate bleeding complications occurred in 19 percent of the patients. PLT transfusion failure was, independently from thrombocytopenia, positively associated with bleeding complications (odds ratio, 3.4; 95% confidence interval, 1.1‐11). Moreover, patients experiencing one or more 24‐hour PLT transfusion failures had, compared to patients always showing a sufficient 24‐hour increment, a significantly reduced median survival of 491 days (interquartile range [IQR], 156‐858 days) versus 825 days (IQR, 355‐996 days), respectively. In a Cox regression model, the effect on survival was independent of therapy, diagnosis, and age.CONCLUSION: Our results suggest that PLT transfusion failure might be a sensitive clinical marker for the occurrence of bleeding and impaired patient survival. PLT transfusion failure, bleeding complications, and decreased survival could be manifestations of a more severe degree of endothelial damage.
Fatal group C streptococcal infection due to transfusion of a bacterially contaminated pooled platelet unit despite routine bacterial culture screening
Authors: Lessa Fernanda , Leparc German F. , Benson Kaaron , Sanderson Roger , Van Beneden Chris A. , Shewmaker Patricia L. , Jensen Bette , Arduino Matthew J. , Kuehnert Matthew J. 
Published: June 2008

BACKGROUND: An elderly man with chronic myelomonocytic leukemia developed respiratory distress and died less than 48 hours after transfusion of a pool of eight whole blood–derived platelets (PLTs). Blood cultures from the recipient and cultures of remnants from the pooled PLT bag grew group C streptococci (GCS). An investigation was conducted to identify both the infection's source and the reasons for the false‐negative screening result.STUDY DESIGN AND METHODS: Red blood cell (RBC) units (cocomponent from the eight donations) were traced, quarantined, and cultured. Specimens from the implicated donor were obtained. Isolates were identified and typed by 16S rRNA and pulsed‐field gel electrophoresis (PFGE). The blood center screening method was reviewed.RESULTS: β‐Hemolytic GCS, cultured from 1 of 8 RBC units, linked the fatal case to a single donor. The donor's throat swab collected 20 days after donation was positive for the presence of GCS, identified as Streptococcus dysgalactiae subsp. equisimilis. Isolates from the recipient, RBC unit, residual PLTs, and donor's throat swab were indistinguishable by PFGE. The donor denied any symptoms of infection before or after donation. PLT bacterial screening at the blood center was performed using a commercially available bacterial detection system (BacT/ALERT, bioMérieux) with a threshold of 15 colony‐forming units per bag.CONCLUSION: An asymptomatic donor was implicated as the source of GCS‐contaminated PLTs. Current screening methods for PLTs are not sufficient to detect all bacterial contamination. Pooled PLTs are a particular challenge because the small volume of individual units places limits on culturing strategies. Improved detection of bacterial contamination of PLTs is needed.
Leukodepletion of autologous whole blood has no impact on perioperative infection rate and length of hospital stay
Authors: Frietsch Thomas , Karger Ralf , Schöler Michael , Huber Daniela , Bruckner Thomas , Kretschmer Volker , Schmidt Susanne , Leidinger Werner , Weiler‐Lorentz Arnulf 
Published: June 2008

BACKGROUND: Several mechanisms have been proposed as possible causes of transfusion‐related immunomodulation (TRIM) after allogeneic transfusion. If one of these mechanisms, the release of mediators of immunity and inflammation (“biologic response modifiers”[BRMs]) from disintegrating blood cells during storage of blood products, really causes TRIM, it should in principle also occur after autologous transfusion. As a consequence, prestorage leukoreduction of autologous blood should be able to prevent the clinical consequences of TRIM after autologous transfusion.STUDY DESIGN AND METHODS: This hypothesis was investigated in a multicenter, double‐blind, randomized controlled trial. A total of 1089 patients scheduled for total hip arthroplasty and eligible for preoperative autologous blood donation were randomly assigned to receive autologous whole blood (AWB) either unmodified or leukoreduced when transfusion was indicated.RESULTS: Neither the primary study outcome, that is, the overall postoperative infection rate (17.3% vs. 17.6%, p = 0.59), nor several secondary outcomes like median length of hospital stay (14 days vs. 14 days, p = 0.17) were significantly different between groups, whether analyzed according to the intention‐to‐treat principle or “as treated.”CONCLUSION: This trial provides strong evidence, from clinically relevant outcome data, that leukoreduction of AWB does not improve postoperative patient outcome and that the release of BRMs from disintegrating blood cells during storage cannot explain the immunomodulatory effect of blood transfusion.