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1.
Pathogens ; 11(3)2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35335667

RESUMO

BACKGROUND AND OBJECTIVES: Since 2015, platelet products have been pathogen-inactivated (PI) at the Luxemburgish Red Cross (LRC) using Riboflavin and UV light (RF-PI). As the LRC should respond to hospital needs at any time, platelet production exceeds the demand, generating a discard rate of 18%. To reduce this, we consider the extension of storage time from 5 to 7 days. This study's objective was to evaluate the in vitro 7-day platelet-storage quality, comparing two PI technologies, RF-PI and amotosalen/UVA light (AM-PI), for platelet pools from whole-blood donations (PPCs) and apheresis platelets collected from single apheresis donation (APCs). MATERIALS AND METHODS: For each product type, 6 double-platelet concentrates were prepared and divided into 2 units; one was treated with RF-PI and the other by AM-PI. In vitro platelet-quality parameters were tested pre- and post-PI, at days 5 and 7. RESULTS: Treatment and storage lesions were observed in PPCs and APCs with both PI methods. We found a higher rate of lactate increase and glucose depletion, suggesting a stronger stimulation of the glycolytic pathway, a higher Annexin V binding, and a loss of swirling in the RF-PI-treated units from day 5. The platelet loss was significantly higher in the AM-PI compared with the RF-PI units. CONCLUSIONS: Results suggest that RF-PI treatment has a higher deleterious impact on in vitro platelet quality compared to AM-PI, but we observed higher loss of platelets with AM-PI due to the post-illumination amotosalen adsorption step. If 7-day storage is needed, it can only be achieved with AM-PI, based on our quality criteria.

2.
Angew Chem Int Ed Engl ; 61(7): e202114513, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-34913236

RESUMO

We report the preparation of potassium acyltrifluoroborates (KATs) from widely available carboxylic acids. Mixed anhydrides of carboxylic acids were prepared using isobutyl chloroformate and transformed to the corresponding KATs using a commercial copper catalyst, B2 (pin)2 , and aqueous KHF2 . This method allows for the facile preparation of aliphatic, aromatic, and amino acid-derived KATs and is compatible with a variety of functional groups including alkenes, esters, halides, nitriles, and protected amines.

3.
Transfus Apher Sci ; 60(5): 103195, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34147359

RESUMO

In 2014-2015, the Luxembourg Red Cross (LRC) implemented a fully automated system (FAS) able to process 4 whole blood units simultaneously, and a pathogen reduction technology (PRT) based on riboflavin and ultraviolet light to improve safety of platelet concentrates (PCs). In this observational study, the impact of both technologies to enable this centralised blood transfusion centre to provide safe and timely blood components supply for the whole country was analysed. Standard quality control parameters for blood components, productivity and safety were compared from data collected with the conventional semi- automated buffy coat method and with FAS/PRT. The FAS decreased processing time when compared with the buffy coat method and facilitated the daily routine at the LRC. Red blood cell concentrates, plasma units and PCs prepared with both methods were conform to the European Directorate for the Quality of Medicines & HealthCare specifications. PCs prepared by FAS showed high yields, with decreased variability when the device-related software (T-Pool Select) was used. PRT had minimal impact on platelet yields and product quality and induced no increase in transfusion reaction notifications. The FAS and PRT transformed the daily routine of blood component manufacture by allowing increased productivity and efficiency, notwithstanding resource containment and without impacting quality, yet promoting safety.


Assuntos
Transfusão de Componentes Sanguíneos/instrumentação , Preservação de Sangue/instrumentação , Preservação de Sangue/métodos , Transfusão de Plaquetas/instrumentação , Automação , Transfusão de Componentes Sanguíneos/métodos , Plaquetas/efeitos dos fármacos , Segurança do Sangue , Eritrócitos/citologia , Humanos , Luxemburgo , Plasma , Contagem de Plaquetas , Transfusão de Plaquetas/métodos , Controle de Qualidade , Cruz Vermelha , Estudos Retrospectivos , Riboflavina/farmacologia , Software
4.
Vox Sang ; 116(1): 53-59, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32797682

RESUMO

BACKGROUND AND OBJECTIVES: The antioxidant power measurement can be useful to validate the execution of the pathogen inactivation treatment of platelet concentrates. The aim of this study is to evaluate the technology on different blood preparations including INTERCEPT and Mirasol treatments that are in routine use in Belgium and Luxemburg. MATERIALS AND METHODS: The antioxidant power measurement was tested on 78 apheresis platelet concentrates and 54 pools of buffy-coats-derived platelet concentrates before and after INTERCEPT treatment. In addition, 100 Reveos platelet pools were tested before and after Mirasol treatment. The antioxidant power was quantified electrochemically using disposable devices and was expressed as equivalent ascorbic acid concentration. RESULTS: Mean results for apheresis platelet concentrates were of 90 ± 14 and 35 ± 10 µmol/l eq. ascorbic acid before and after INTERCEPT treatment, respectively. The mean results for pools of buffy-coats-derived platelet concentrates were of 81 ± 10 and 29 ± 4 eq. µmol/l ascorbic acid before and after INTERCEPT treatment, respectively. For buffy-coats-derived platelet concentrates treated by Mirasol technology, the mean results were of 98 ± 11 and 32 ± 10 µmol/l eq. ascorbic acid before and after illumination, respectively. CONCLUSION: The antioxidant power significantly decreases with pathogen inactivation treatments for platelet concentrates treated by INTERCEPT or Mirasol technologies.


Assuntos
Antioxidantes/análise , Plaquetas/química , Preservação de Sangue , Plaquetas/efeitos da radiação , Feminino , Furocumarinas , Humanos , Masculino , Plaquetoferese , Raios Ultravioleta
5.
Angew Chem Int Ed Engl ; 60(8): 3918-3922, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33231353

RESUMO

We report the synthesis of potassium acyltrifluoroborates (KATs) by a palladium-catalyzed cross-coupling of boronic acids and the thioimidate KAT transfer reagent. The combination of widely available aryl- and vinylboronic acids with commercially available thioimidate 1 using catalytic PdII and a CuII additive enables the preparation of KATs in high yields and with good functional group tolerance. This formal insertion of CO into organoboronic acids can also be applied to boronic acid pinacol esters and potassium organotrifluoroborates using a slightly modified procedure. The cross-coupling can be telescoped into the one-pot synthesis of amides and α-aminotrifluoroborates by exploiting the unique chemistry of KATs and their trifluoroborate iminium (TIM) derivatives.

6.
Chem Sci ; 11(29): 7609-7614, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-34094137

RESUMO

Although highly effective for most amide syntheses, the activation of carboxylic acids requires the use of problematic coupling reagents and is often poorly suited for challenging cases such as N-methyl amino acids. As an alternative to both secondary and tertiary amides, we report their convenient synthesis by the rapid oxidation of trifluoroborate iminiums (TIMs). TIMs are easily prepared by acid-promoted condensation of potassium acyltrifluoroborates (KATs) and amines and are cleanly and rapidly oxidized to amides with hydrogen peroxide. The overall transformation can be conducted either as a one-pot procedure or via isolation of the TIM. The unique nature of the neutral, zwitterionic TIMs makes possible the preparation of tertiary amides via an iminium species that would not be accessible from other carbonyl derivatives and can be conducted in the presence of unprotected functional groups including acids, alcohols and thioethers. In preliminary studies, this approach was applied to the late-stage modifications of long peptides and the iterative synthesis of short, N-methylated peptides without the need for coupling agents.

7.
Chem Sci ; 9(23): 5191-5196, 2018 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-29997873

RESUMO

We report the facile formation of trifluoroborate-iminiums (TIMs) from potassium acyltrifluoroborates (KATs) and the transformation of TIMs to α-aminotrifluoroborates by reduction or Grignard additions. Conditions for the hydrolysis of α-aminotrifluoroborates to α-aminoboronic acids, which are important biologically active compounds, were established. This new methodology allows access to sterically demanding α-aminoboronic acids that are not easily prepared with currently available methods. This work also introduces TIMs, that can be easily prepared and handled, as a new category of functional groups that serve as precursors to valuable organic compounds.

8.
Org Lett ; 20(13): 4044-4047, 2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29938515

RESUMO

The cross-coupling of α-aminoalkyltrifluoroborates and Grignard reagents to form N, N-substituted α-tertiary amines (ATAs) is reported. Key to the success of this reaction is the unexpected oxidation of the α-aminoalkyltrifluoroborate to the corresponding iminium cation by commercially available Barluenga's reagent. Various Grignard reagents added smoothly, enabling the synthesis of a variety of ATAs, which are of high value for medicinal chemistry and drug development. Many of the reported examples are not accessible by the established methods.

9.
Transfusion ; 56(12): 3033-3041, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27807857

RESUMO

BACKGROUND: Blood products use has increased in France between 2000 and 2011. To understand the reasons for this increase, data about transfused patients and transfusion practices needed to be updated. STUDY DESIGN AND METHODS: A nationwide cross-sectional survey was performed with health care establishments. Diagnoses and indication for the transfusion, pretransfusion laboratory results, and blood products used were collected during a randomly selected 24-hour period in 2011. All patients who received at least one blood product delivered on the survey day were included. RESULTS: A total of 10,794 blood products were requested for 4720 patients: 8688 red blood cell (RBC) units, 842 platelet (PLT) concentrates, and 1264 fresh-frozen plasma (FFP) units. Hematologic and cancer pathologies included 46% of transfused patients, 34% of the patients had transfusions in a surgical context, and 32.4% of transfused patients were receiving medication with an impact on transfusion. Nearly half of RBC transfusions were performed with hemoglobin levels of less than 8 g/dL. PLT transfusions for prophylactic indication were prescribed with PLT counts of less than 20 × 109 and 50 × 109 /L in 56.9 and 86.6% of patients, respectively. RBCs and PLTs transfusion practices were in agreement with national guidelines. FFP units were involved in 8.0% of all prescriptions. Among these, 57.4% were requested in the context of an acute hemorrhage and 8.4% for plasma exchange. The median of FFP use (n = 2) in a nonsurgical context, excluding plasma exchange, suggests an insufficient dosing of FFP. CONCLUSION: Except for insufficient FFP dosing per patient and limitations on assessment of indications for prescribing, transfusion practices were in agreement with national guidelines.


Assuntos
Transfusão de Sangue/estatística & dados numéricos , Estudos Transversais , Transfusão de Eritrócitos/estatística & dados numéricos , França/epidemiologia , Humanos , Plasma , Troca Plasmática/estatística & dados numéricos , Transfusão de Plaquetas/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Inquéritos e Questionários
10.
Transfusion ; 43(7): 878-84, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12823747

RESUMO

BACKGROUND: The implementation of a quality-assurance program is a major requirement to ensure quality and safety of the final PBPC components intended for clinical use. It is not clear whether the quantification of CFU-GM and CD34+ cells should be done on fresh components and after cryopreservation, which better represents the actual composition of the graft. STUDY DESIGN AND METHODS: Correlation between prefreeze and postthaw MNCs, CD34+ cells, and CFU-GM collected from 126 patients undergoing BMT (n=43) or PBPC (n =83) transplantation were evaluated. The statistical incidence of prefreeze and postthaw parameters as well as patient characteristics and conditioning regimens on hematologic recovery were analyzed. RESULTS: By multivariate analysis, prefreeze and postthaw CD34+ cells were the only two variables significantly and independently correlated to hematologic recovery. Low prefreeze and postthaw CD34+ cell numbers associated to a low CD34+ yield characterize PBPC grafts from patients who have the slowest hematologic recovery. The postthaw PBPC CD34+ cell number can be estimated before conditioning regimen by thawing a small aliquot of the graft. CONCLUSION: In association to prefreeze CD34+ cell number and to CD34+ yield, postthaw CD34+ cell number may be useful in monitoring cell loss during processing and identifying patients at risk of slow PBPC engraftment.


Assuntos
Antígenos CD34/análise , Contagem de Células , Criopreservação , Células-Tronco Hematopoéticas/citologia , Transplante de Células-Tronco de Sangue Periférico , Adulto , Plaquetas/citologia , Transplante de Medula Óssea , Feminino , Citometria de Fluxo , Sobrevivência de Enxerto , Granulócitos/citologia , Hematopoese , Temperatura Alta , Humanos , Masculino , Transfusão de Plaquetas , Transplante Autólogo , Resultado do Tratamento
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