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991.
Sixten Krper Bernd Jahrsdrfer Victor M. Corman Jan Pilch Patrick Wuchter Rainer Blasczyk Rebecca Müller Torsten Tonn Tamam Bakchoul Richard Schfer David Juhl Tatjana Schwarz Nina Gdecke Thomas Burkhardt Michael Schmidt Thomas Appl Hermann Eichler Harald Klüter Christian Drosten Erhard Seifried Hubert Schrezenmeier 《Transfusion medicine and hemotherapy : offizielles Organ der Deutschen Gesellschaft fur Transfusionsmedizin und Immunhamatologie》2021,48(3):137
BackgroundConvalescent plasma is one of the treatment options for COVID-19 which is currently being investigated in many clinical trials. Understanding of donor and product characteristics is important for optimization of convalescent plasma.MethodsPatients who had recovered from COVID-19 were recruited as donors for COVID-19 convalescent plasma (CCP) for a randomized clinical trial of CCP for treatment of severe COVID-19 (CAPSID Trial). Titers of neutralizing antibodies were measured by a plaque-reduction neutralization test (PRNT). Correlation of antibody titers with host factors and evolution of neutralizing antibody titers over time in repeat donors were analysed.ResultsA series of 144 donors (41% females, 59% males; median age 40 years) underwent 319 plasmapheresis procedures providing a median collection volume of 850 mL and a mean number of 2.7 therapeutic units per plasmapheresis. The majority of donors had a mild or moderate course of COVID-19. The titers of neutralizing antibodies varied greatly between CCP donors (from <1:20 to >1:640). Donor factors (gender, age, ABO type, body weight) did not correlate significantly with the titer of neutralizing antibodies. We observed a significant positive correlation of neutralization titers with the number of reported COVID-19 symptoms and with the time from SARS-CoV-2 diagnosis to plasmapheresis. Neutralizing antibody levels were stable or increased over time in 58% of repeat CCP donors. Mean titers of neutralizing antibodies of first donation and last donation of repeat CCP donors did not differ significantly (1:86 at first compared to 1:87 at the last donation). There was a significant correlation of neutralizing antibodies measured by PRNT and anti-SARS-CoV-2 IgG and IgA antibodies which were measured by ELISA. CCP donations with an anti-SARS-CoV-2 IgG antibody content above the 25th percentile were substantially enriched for CCP donations with higher neutralizing antibody levels.ConclusionWe demonstrate the feasibility of collection of a large number of CCP products under a harmonized protocol for a randomized clinical trial. Titers of neutralizing antibodies were stable or increased over time in a subgroup of repeat donors. A history of higher number of COVID-19 symptoms and higher levels of anti-SARS-CoV-2 IgG and IgA antibodies in immunoassays can preselect donations with higher neutralizing capacity. 相似文献
992.
Patrick P. Torreiter Susanne Macher Eva-Maria Matzhold Bernhard Resch Philipp Klaritsch Günther F. Krmczi Helene Polin Leopold Neuhold Marlies Schnbacher Peter Schlenke Thomas Wagner 《Transfusion medicine and hemotherapy : offizielles Organ der Deutschen Gesellschaft fur Transfusionsmedizin und Immunhamatologie》2021,48(3):183
BackgroundThe development of allo-anti-Rh17 (anti-Hr0) in a −D– phenotype whose red blood cells (RBCs) lack CcEe antigens is most likely triggered by transfusion, transplantation, or pregnancy. Gene conversion is the predominating factor in generating RHD-CE-D and RHCE-D-CE hybrids like −D–.MethodsWe report here immunohematological and obstetrical data from 2 of the 5 pregnancies of a 24-year-old woman presenting with the −D– phenotype with anti-Rh17. Blood group typing, antibody screening, antibody differentiation, direct antiglobulin test (DAT), and antibody titers were performed by routine gel technology and tube testing. Additionally, molecular genetic analysis was performed. Fetal surveillance was done by sonographic evaluation of the fetal middle cerebral artery peak systolic velocity (MCA-PSV).ResultsBlood group typing showed O, C-c-D+E-e- and the DAT was negative. DNA sequencing revealed homozygosity for an RHCE-D(3–9)-CE null allele. Anti-Rh17 titers in the fourth pregnancy remained between 1:8 and 1:128, and no signs for a fetal anemia were observed. However, in the fifth pregnancy, the antibody titers increased up to 1:4,096. Signs of moderate fetal anemia were detected and cesarean section was performed at 34 + 6 weeks of gestation. The newborn presented with hemolytic anemia (cord blood hemoglobin [Hb] = 8.5 mg/dL). She received 2 compatible (small) packed RBC concentrates, phototherapy, and intravenous immunoglobulins.ConclusionOur case shows that the risk for hemolytic complications increases with the number of pregnancies of sensitized women. Only people who also lack CcEe antigens are compatible as donors. The role of such rare donors as lifesavers, their freedom, and voluntariness conflict with the urgent need for compatible blood. 相似文献
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Patrick Blin Caroline Dureau-Pournin Jacques Bnichou Yves Cottin Patrick Mismetti Abdelilah Abouelfath Regis Lassalle Ccile Droz Nicholas Moore 《Am J Cardiovasc Drugs》2020,20(1):81-103
Clinical trials have indicated that the direct-acting oral anticoagulants dabigatran and rivaroxaban have better risk/benefit profiles than do vitamin K antagonists (VKAs) for stroke prevention in non-valvular atrial fibrillation (NVAF). Our objective was to compare the 1-year real-life risk of major clinical events with dabigatran or rivaroxaban versus VKAs for NVAF. This was a high-dimensional propensity score (hdPS)-matched cohort study of new users of dabigatran, rivaroxaban or VKAs for NVAF in the French national healthcare systems database in 2013 followed-up for 1 year [22]. Hazard ratios (HRs) with 95% confidence intervals (CIs) for clinical events and death were determined during exposure. In 2013, a total of 103,101 new anticoagulant users had definite NVAF: 44,653 VKA, 27,060 dabigatran, and 31,388 rivaroxaban. In matched populations, HRs were as follows for dabigatran versus VKAs (20,489 per group): stroke and systemic embolism (SSE) 0.75 (95% CI 0.63–0.88), clinically relevant bleeding (CRB) 0.58 (95% CI 0.51–0.66), hemorrhagic stroke (HS) 0.22 (95% CI 0.14–0.36), gastrointestinal bleeding (GIB) 0.98 (95% CI 0.80–1.19), acute coronary syndrome (ACS) 0.79 (95% CI 0.65–0.95), death 0.74 (95% CI 0.67–0.82), composite (any of the above) 0.71 (95% CI 0.66–0.76). For matched rivaroxaban versus VKA (23,053 per group) HRs were as follows: SSE 0.98 (95% CI 0.85–1.14), CRB 0.83 (95% CI 0.75–0.92), HS 0.65 (95% CI 0.49–0.87), GIB 1.08 (95% CI 0.90–1.30), ACS 0.84 (95% CI 0.71–1.00), death 0.77 (95% CI 0.71–0.84), composite 0.84 (95% CI 0.79–0.89). Numbers needed to treat to observe one fewer death were 49 ± 0.05 with dabigatran or rivaroxaban versus VKAs. Consistent with results from clinical trials and other observational studies, dabigatran and rivaroxaban were at least as effective and safer than VKAs for the prevention of thromboembolic events in NVAF over 1 year in the French population. European Medicines Agency EUPAS 13017 (www.encepp.eu) Clinicaltrials.gov id NCT02785354. 相似文献
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997.
Amanda Cohn Rosslyn O'Connor Kari Lancaster Patrick Rawstorne 《Drugs (Abingdon, England)》2020,27(4):261-270
AbstractMedia and politicians both influence public opinion and policy responses to illicit drug issues. This study examines the contribution each may have made in Australia in 2015 to the problem and politics streams of the policy process, as outlined in Kingdon’s ‘multiple streams’ heuristic, when a National Ice Taskforce responded to increased public, political and media concern about methamphetamine use. A retrospective content analysis compared the frequency and content of articles about methamphetamine in print media (N?=?639) and federal parliament speeches (N?=?158) in 2015. Peaks in the number of media articles and debates in parliament followed the establishment and interim findings of the Ice Taskforce. The findings showed that politicians more frequently framed methamphetamine use as a crisis or epidemic than the media. Both frequently portrayed cost to society as the consequence of methamphetamine use and often cited law enforcement sources. The media most frequently positioned methamphetamine users as criminal or deviant compared to politicians who did not position the user or positioned them as an addict or victim. This analysis highlights the convergence of the problem and politics streams and suggests they are not independent as first posited by Kingdon. 相似文献
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999.
Daniel S.?EngelerEmail author Christoph?Schwab Armin F.?Th?ni Werner?Hochreiter Ladislav?Prikler Stefan?Suter Patrick?Stucki Johann?Schiefer Ludwig?Plasswilm Hans-Peter?Schmid Paul Martin?Putora 《Strahlentherapie und Onkologie》2015,191(10):787-791
Background
Permanent low-dose-rate brachytherapy (BT) with iodine 125 is an established curative treatment for localized prostate cancer. After treatment, prostate-specific antigen (PSA) kinetics may show a transient rise (PSA bounce). Our aim was to investigate the association of PSA bounce with biochemical control.Patients and methods
Patients treated with BT in Switzerland were registered in a prospective database. Only patients with a follow-up of at least 2 years were included in our analysis. Clinical follow-up and PSA measurements were assessed after 1.5, 3, 6, and 12 months, and annually thereafter. If PSA increased, additional follow-up visits were scheduled. Cases of PSA bounce were defined as a rise of at least 0.2 ng/ml above the initial PSA nadir with a subsequent decline to or below the initial nadir without treatment. Biochemical failure was defined as a rise to nadir +?2 ng/ml.Results
Between March 2001 and November 2010, 713 patients with prostate cancer undergoing BT with at least 2 years of follow-up were registered. Median follow-up time was 41 months. Biochemical failure occurred in 28 patients (3.9?%). PSA bounce occurred in 173 (24.3?%) patients; only three (1.7?%) patients with PSA bounce developed biochemical failure, in contrast to 25 (4.6?%) patients without previous bounce (p?<?0.05). The median time to bounce was 12 months, the median time to biochemical failure was 30 months. The median bounce increase was 0.78 ng/ml. Twenty-eight patients with bounce (16.5?%) had a transient PSA rise of +?2 ng/ml above the nadir.Conclusion
In most cases, an early increase in PSA after BT indicates PSA bounce and is associated with a lower risk of biochemical failure.1000.