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1.
Toxicol Lett ; 319: 58-65, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31730884

RESUMO

This study proposes the application of the comet assay for the evaluation of DNA damage from frozen human whole blood samples that could be readily used in human biomonitoring and epidemiological studies. It was done on simply frozen whole blood samples collected from male volunteers (N = 60) aliquoted in small volumes and stored at -80 °C without the addition of cryopreservatives for a period of 5 years. To test the applicability of the alkaline comet assay for the evaluation of DNA damage in frozen whole blood, samples were quickly thawed at 37 °C and immediately embedded in an agarose matrix followed by an alkaline comet assay procedure. We concluded that the whole blood freezing and prolonged storage do not severely affect comet assay values, although background values were higher compared to our historical control data from the fresh whole blood. Even the influence of the variables tested, such as age, body mass index, smoking habit and alcohol consumption were in agreement with our previous data using fresh blood. The obtained results suggest that the comet assay could be applied to frozen blood samples, if properly stored, even for decades, which would certainly facilitate large-scale human biomonitoring and long-term epidemiological studies.


Assuntos
Preservação de Sangue/efeitos adversos , Sangue , Ensaio Cometa/métodos , Dano ao DNA , Adolescente , Adulto , Fatores Etários , Idoso , Índice de Massa Corporal , Criopreservação , Congelamento , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Adulto Jovem
2.
Vox Sang ; 114(7): 694-700, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31286533

RESUMO

OBJECTIVE: Fresh whole blood (WB) has been used in military applications and cardiac surgery. We undertook a study of the coagulation properties of refrigerated WB stored for 21 days and compared them with the properties of reconstituted WB. STUDY DESIGN AND METHODS: Ten WB units were obtained from healthy volunteer donors and stored at 4 ± 2°C. Samples were obtained on Days 1, 2, 4, 6, 8, 10, 14 and 21 from the WB units. Ten units of reconstituted WB were prepared with a ratio of red cells, platelets and plasma of 1:1:1. Tests included complete blood count, electrolyte, routine coagulation, blood coagulation factor and thromboelastography. RESULTS: There was a progressive decline in Hb, WBC, PLT, sodium and coagulation factors but a progressive increase in APTT, PT and potassium in WB. The concentrations of factor (F)V and FVIII as well as FII and FX of WB were higher before Days 4, 2, 8 and 14, respectively, compared with the concentrations of reconstituted WB. The concentrations of FVII, FIX, FXI and FXII in WB were found to be equal to or higher than those in reconstituted WB throughout the course of 21 days. TEG variables in all WB units were normal throughout the course of 10 days. The mean PT and APTT of WB were lower than those of reconstituted WB before Days 14 and 10, respectively. CONCLUSION: This study suggests that the coagulation properties of refrigerated WB were equal to or superior to those of reconstituted WB for a minimum of 10 days.


Assuntos
Coagulação Sanguínea , Preservação de Sangue/métodos , Criopreservação/métodos , Preservação de Sangue/efeitos adversos , Humanos , Tromboelastografia/métodos , Tempo de Coagulação do Sangue Total/métodos
3.
Biomolecules ; 9(5)2019 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-31126114

RESUMO

Liquid-chromatography mass spectrometry is commonly used to identify and quantify metabolites from biological samples to gain insight into human physiology and pathology. Metabolites and their abundance in biological samples are labile and sensitive to variations in collection conditions, handling and processing. Variations in sample handling could influence metabolite levels in ways not related to biology, ultimately leading to the misinterpretation of results. For example, anticoagulants and preservatives modulate enzyme activity and metabolite oxidization. Temperature may alter both enzymatic and non-enzymatic chemistry. The potential for variation induced by collection conditions is particularly important when samples are collected in remote locations without immediate access to specimen processing. Data are needed regarding the variation introduced by clinical sample collection processes to avoid introducing artifact biases. In this study, we used metabolomics and lipidomics approaches paired with univariate and multivariate statistical analyses to assess the effects of anticoagulant, temperature, and time on healthy human plasma samples collected to provide guidelines on sample collection, handling, and processing for vaccinology. Principal component analyses demonstrated clustering by sample collection procedure and that anticoagulant type had the greatest effect on sample metabolite variation. Lipids such as glycerophospholipids, acylcarnitines, sphingolipids, diacylglycerols, triacylglycerols, and cholesteryl esters are significantly affected by anticoagulant type as are amino acids such as aspartate, histidine, and glutamine. Most plasma metabolites and lipids were unaffected by storage time and temperature. Based on this study, we recommend samples be collected using a single anticoagulant (preferably EDTA) with sample processing at <24 h at 4 °C.


Assuntos
Anticoagulantes/farmacologia , Preservação de Sangue/efeitos adversos , Metaboloma , Plasma/química , Anticoagulantes/efeitos adversos , Humanos , Lipídeos/análise , Plasma/efeitos dos fármacos , Temperatura Ambiente
4.
Vox Sang ; 114(3): 198-206, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30734312

RESUMO

BACKGROUND/OBJECTIVES: We compared the ex vivo haemostatic capacity of RTFP24 with FFP upon thawing and >24 h post-thaw. We included thrombin generation (TG) as few studies had compared global haemostatic function, and most did not directly compare RTFP24 with FFP >24 h post-thaw. MATERIALS/METHODS: Twenty units each of RTFP24 and FFP were measured for coagulation factors and thrombin generation upon thawing (D0) and 4 days post-thaw (D4). Labile factors were also measured from D1 to D3. 10 single cryoprecipitate units were each prepared from FFP and RTFP24, and measured for FXIII, FVIII and fibrinogen at D0. RESULTS: At D0, RTFP24 was comparable to FFP except for lower FV, protein S, endogenous thrombin potential (ETP) and higher FXIII. These differences were likely clinically insignificant since 95% and 80% of RTFP24 met our laboratory's reference ranges for FV/protein S and ETP, respectively. There were no differences between RTFP24- and FFP-derived cryoprecipitate. At D4, RTFP24 was comparable to FFP except for lower FV, ETP, and higher FXI and FXIII. More RTFP24 than FFP had ETP lower than our laboratory's reference range (45% vs 15%). Multiple coagulation factors and all TG parameters declined from their respective baselines. The percentage declines were comparable or less in RTFP24, except for protein C, fibrinogen and time to peak. CONCLUSION: RTFP24 and FFP, and their derived cryoprecipitate have comparable haemostatic capacity upon thawing. RTFP24 has poorer TG potential than FFP >24 h post-thaw, not supporting universal extension of RTFP24's shelf life except to facilitate urgent transfusions for massive haemorrhage.


Assuntos
Preservação de Sangue/métodos , Criopreservação/métodos , Plasma/metabolismo , Coagulação Sanguínea , Fatores de Coagulação Sanguínea/metabolismo , Preservação de Sangue/efeitos adversos , Preservação de Sangue/normas , Criopreservação/normas , Fibrinogênio/metabolismo , Humanos , Proteína S/metabolismo , Trombina/metabolismo
5.
Vox Sang ; 114(2): 174-177, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30565226

RESUMO

We prospectively studied the dose-dependent effect of transfused stored red blood cells (RBCs) on recipient RBC indices, deformability and cell density in 10 patients administered stored RBCs for blood transfusion during general surgery. There were dose-dependent decreases in mean corpuscular volume and increases in mean corpuscular haemoglobin concentration after completion of 4- and 6-unit stored RBC transfusions. The amount of dense populations increased proportionately with the amount of stored RBCs transfused. The maximal deformability index value was significantly and dose-dependently decreased, suggesting that hemodynamic blood flow, especially the microcirculation may be impaired in patients who receive large amounts of stored RBCs.


Assuntos
Preservação de Sangue/efeitos adversos , Índices de Eritrócitos/fisiologia , Transfusão de Eritrócitos/efeitos adversos , Eritrócitos/fisiologia , Eritrócitos/citologia , Feminino , Humanos , Masculino
6.
Microrna ; 8(1): 36-42, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29779489

RESUMO

BACKGROUND: A small GTPase Protein, the Ras-related Protein 1 (RAP1), abundant in platelets is known to be activated following agonist-induced platelet activation, suggesting that RAP1 downregulation could, in turn, reduce platelet activation in storage. Our objective of this study is to identify RAP1 regulating miRNAs and their role in platelet activation during storage. METHODS: We applied MS2-TRAP (tagged RNA affinity purification) methodology to enrich miRNAs that target the 3' untranslated region (3'UTR) of RAP1 mRNA in two mammalian cell lines followed by miRNA identification by microarray of total RNA samples enriched for miRNAs. Data analyses were done using different bioinformatics approaches. The direct miR:RAP1 3'UTR interaction was confirmed by using a dual luciferase reporter gene expression system in a mammalian cell line. Subsequently, platelets were transfected with one selected miR to evaluate RAP1 downregulation by this miRNA and its effect on platelet activation. RESULTS: Six miRNAs (miR-320c, miR-181a, miR-3621, miR-489, miR-4791 and miR-4744) were identified to be enriched in the two cell lines tested. We randomly selected miR-320c for further evaluation. The luciferase reporter assay system confirmed the direct interaction of miR-320c with RAP1 3'UTR. Further, in platelets treated with miR-320c, RAP1 protein expression was decreased and concomitantly, platelet activation was also decreased. CONCLUSION: Overall, the results demonstrate that miRNA-based RAP1 downregulation in ex vivo stored platelets reduces platelet activation.


Assuntos
Plaquetas/metabolismo , Preservação de Sangue/efeitos adversos , MicroRNAs/genética , Ativação Plaquetária , Proteínas de Ligação a Telômeros/genética , Regulação para Baixo , Células HeLa , Humanos , MicroRNAs/metabolismo , Proteínas de Ligação a Telômeros/metabolismo
7.
Cochrane Database Syst Rev ; 12: CD010801, 2018 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-30578732

RESUMO

BACKGROUND: Red blood cell (RBC) transfusion is a common treatment for anaemia in many conditions. The safety and efficacy of transfusing RBC units that have been stored for different durations before a transfusion is a current concern. The duration of storage for a RBC unit can be up to 42 days. If evidence from randomised controlled trials (RCT) were to indicate that clinical outcomes are affected by storage duration, the implications for inventory management and clinical practice would be significant. OBJECTIVES: To assess the effects of using red blood cells (RBCs) stored for a shorter versus a longer duration, or versus RBCs stored for standard practice duration, in people requiring a RBC transfusion. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, PubMed (for epublications), LILACS, Transfusion Evidence Library, Web of Science CPCI-S and four international clinical trial registries on 20 November 2017. SELECTION CRITERIA: We included RCTs that compared transfusion of RBCs of shorter versus longer storage duration, or versus standard practice storage duration. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. MAIN RESULTS: We included 22 trials (42,835 participants) in this review.The GRADE quality of evidence ranged from very low to moderate for our primary outcome of in-hospital and short-term mortality reported at different time points.Transfusion of RBCs of shorter versus longer storage duration Eleven trials (2249 participants) compared transfusion of RBCs of shorter versus longer storage duration. Two trials enrolled low birth weight neonates, two enrolled children with severe anaemia secondary to malaria or sickle cell disease, and eight enrolled adults across a range of clinical settings (intensive care, cardiac surgery, major elective surgery, hospitalised in-patients, haematology outpatients). We judged only two trials to be at low risk of bias across all domains; most trials had an unclear risk for multiple domains.Transfusion of RBCs of shorter versus longer storage duration probably leads to little or no difference in mortality at seven-day follow-up (risk ratio (RR) 1.42, 95% confidence interval (CI) 0.66 to 3.06; 1 trial, 3098 participants; moderate quality evidence) or 30-day follow-up (RR 0.85, 95%CI 0.50 to 1.45; 2 trials, 1121 participants; moderate quality evidence) in adults undergoing major elective cardiac or non-cardiac surgery.For neonates, no studies reported on the primary outcome of in-hospital or short-term mortality. At 40 weeks gestational age, the effect of RBCs of shorter versus longer storage duration on the risk of death was uncertain, as the quality of evidence is very low (RR 0.90, 95% CI 0.41 to 1.85; 1 trial, 52 participants).The effect of RBCs of shorter versus longer storage duration on the risk of death in children with severe anaemia was also uncertain within 24 hours of transfusion (RR 1.50, 95% CI 0.43 to 5.25; 2 trials, 364 participants; very low quality evidence), or at 30-day follow-up (RR 1.40, 95% CI 0.45 to 4.31; 1 trial, 290 participants; low quality evidence).Only one trial, in children with severe anaemia (290 participants), reported adverse transfusion reactions. Only one child in each arm experienced an adverse reaction within 24 hours of transfusion.Transfusion of RBCs of shorter versus standard practice storage duration Eleven trials (40,588 participants) compared transfusion of RBCs of shorter versus standard practice storage duration. Three trials enrolled critically ill term neonates; two of these enrolled very low birth weight neonates. There were no trials in children. Eight trials enrolled critically ill and non-critically ill adults, with most being hospitalised. We judged four trials to be at low risk of bias across all domains with the others having an unclear risk of bias across multiple domains.Transfusion of RBCs of shorter versus standard practice storage duration probably leads to little or no difference in adult in-hospital mortality (RR 1.05, 95% CI 0.97 to 1.14; 4 trials, 25,704 participants; moderate quality evidence), ICU mortality (RR 1.06, 95% CI 0.98 to 1.15; 3 trials, 13,066 participants; moderate quality evidence), or 30-day mortality (RR 1.04, 95% CI 0.96 to 1.13; 4 trials, 7510 participants;moderate quality evidence).Two of the three trials that enrolled neonates reported that there were no adverse transfusion reactions. One trial reported an isolated case of cytomegalovirus infection in participants assigned to the standard practice storage duration group. Two trials in critically ill adults reported data on transfusion reactions: one observed no difference in acute transfusion reactions between arms (RR 0.67, 95% CI 0.19 to 2.36, 2413 participants), but the other observed more febrile nonhaemolytic reactions in the shorter storage duration arm (RR 1.48, 95% CI 1.13 to 1.95, 4919 participants).Trial sequential analysis showed that we may now have sufficient evidence to reject a 5% relative risk increase or decrease of death within 30 days when transfusing RBCs of shorter versus longer storage duration across all patient groups. AUTHORS' CONCLUSIONS: The effect of storage duration on clinically important outcomes has now been investigated in large, high quality RCTs, predominantly in adults. There appears to be no evidence of an effect on mortality that is related to length of storage of transfused RBCs. However, the quality of evidence in neonates and children is low. The current practice in blood banks of using the oldest available RBCs can be continued safely. Additional RCTs are not required, but research using alternative study designs, should focus on particular subgroups (e.g. those requiring multiple RBC units) and on factors affecting RBC quality.


Assuntos
Anemia/terapia , Preservação de Sangue , Transfusão de Eritrócitos , Eritrócitos , Adulto , Anemia/etiologia , Anemia/mortalidade , Anemia Falciforme/complicações , Preservação de Sangue/efeitos adversos , Preservação de Sangue/mortalidade , Segurança do Sangue , Criança , Transfusão de Eritrócitos/efeitos adversos , Transfusão de Eritrócitos/mortalidade , Guias como Assunto , Mortalidade Hospitalar , Humanos , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Malária/complicações , Ensaios Clínicos Controlados Aleatórios como Assunto , Tamanho da Amostra , Fatores de Tempo
8.
Transfusion ; 58(11): 2604-2610, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30293236

RESUMO

BACKGROUND: The transfusion of platelet concentrates (PCs) contaminated with bacteria may cause serious, and even fatal, septic reactions in patients. The aim of this study was to compare the VersaTREK with the BACTEC FX automated culture systems for screening bacterial contamination, directly after the delay of 24 hours of preparation to obtain the final pooled buffy coat PCs, to prevent transfusion-transmitted bacterial infections. STUDY DESIGN AND METHODS: Seven bacterial strains were each inoculated into five replicate pooled buffy coat PCs at approximately 100 colony-forming units/unit, and 5- or 10-mL samples were inoculated into duplicate aerobic culture bottles. The time and detection rates were compared between BACTEC FX, as a reference method, and VersaTREK. RESULTS: Time to detection was significantly shorter using VersaTREK for most species detected by both systems for the volumes tested. Of 70 VersaTREK cultures, 69 (98.57% detection rate) were positive after 24 hours of incubation with the 5-mL sample. In contrast, the BACTEC FX system detected all positive samples in PCs for the volume of 10 mL, although seven samples were false negatives for the 5-mL volume. CONCLUSION: The VersaTREK system compared favorably to the BACTEC FX system for 5-mL volumes (p < 0.05) and could be considered a potential method for detecting bacterial contamination in PC samples directly after 24 hours of preparation of the final pooled buffy coat PCs.


Assuntos
Plaquetas/microbiologia , Técnicas Bacteriológicas/métodos , Preservação de Sangue/efeitos adversos , Humanos , Transfusão de Plaquetas/efeitos adversos
9.
Analyst ; 143(24): 6006-6013, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30357129

RESUMO

The standard practice in blood banks worldwide involves storage of red blood cells (RBCs) in plastic bags until they are needed for transfusion. During storage, the cells gradually degrade in functionality, a condition described as RBC storage lesion. Standard analytical techniques cannot assess the blood quality without breaching the sterility of the transfusion bag. In this study, we employed a commercially available spatially offset Raman spectroscopy (SORS) system using a custom designed protocol to non-invasively explore the biochemical changes in RBC concentrate of healthy donors over a storage period of approximately 42 days in standard transfusion bags, under standard storage conditions. The results reveal an increase in the oxygenation state of haemoglobin over the storage period for all donors, but different profiles for each donor. This study demonstrates the feasibility of acquiring consistent biochemical information relevant to the quality of stored blood, in situ through sealed blood transfusion bags using a commercially available instrument.


Assuntos
Preservação de Sangue/efeitos adversos , Transfusão de Sangue/instrumentação , Eritrócitos/metabolismo , Hemoglobinas/metabolismo , Humanos , Masculino , Oxigênio/sangue , Análise Espectral Raman/métodos
10.
Transfusion ; 58(11): 2529-2537, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30298928

RESUMO

BACKGROUND: The characteristics of red blood cell (RBC) products change after 2 weeks of cold storage. It is unclear whether older RBCs affect mortality after liver transplantation. This retrospective cohort study aimed to evaluate the association between the age of transfused RBCs and death after living donor liver transplantation (LDLT). STUDY DESIGN AND METHODS: Of 200 recipients who underwent LDLT, 118 who received RBCs with a mean storage duration of less than 10 days (shorter storage group) were compared with 82 with an RBC mean storage duration of more than 14 days (longer storage group). Key exclusion criteria were transfusion of very fresh RBCs stored for less than 4 days and transfusion of old RBCs in recipients of the shorter storage group. The primary outcome was posttransplant overall death. Survival analysis was performed using the Cox model. RESULTS: Mean RBC storage duration was 7 days in the shorter storage group and 17 days in the longer storage group. Death probability at 1, 2, and 5 years posttransplant was 5.1%, 7.6%, and 13.6% in the shorter storage group, respectively, and 6.1%, 8.5%, and 13.5% in the longer storage group. Death risk was comparable between the two groups in univariable (hazard ratio [HR] 1.00, 95% confidence interval [CI], 0.47-2.16, p = 0.991) and multivariable (HR 1.07, 95% CI, 0.46-2.50, p = 0.882) analyses. Graft failure risk was also comparable (HR 1.04, 95% CI, 0.50-2.18, p = 0.916). Hepatocellular carcinoma recurrence probability at 1, 2, and 5 years was 10.8%, 15.4%, and 23.1%, respectively, in the shorter storage group and 11.4%, 15.9%, and 20.7% in the longer storage group (HR 0.84, 95% CI, 0.37-1.89, p = 0.670). No significant differences were observed regarding graft regeneration/function, vascular/biliary complications, acute kidney injury, surgical site infection, or rejection (p > 0.05). CONCLUSIONS: No evidence was found that transfusion of old RBCs contributes to death after LDLT.


Assuntos
Eritrócitos/citologia , Transplante de Fígado/efeitos adversos , Adulto , Preservação de Sangue/efeitos adversos , Contagem de Eritrócitos , Humanos , Masculino , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida
11.
J Thromb Thrombolysis ; 46(4): 534-540, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30218271

RESUMO

Platelet receptor GPVI plays an important role in platelet firm adhesion to site of vascular injury. Receptor ligation with collagen, in company with other agonist/receptor interactions, augments inside out signaling pathways leading to platelet aggregation and thrombus formation. As GPVI expression is significantly modulated by ectodomain shedding, this study aimed to examine whether GPVI shedding functionally affects collagen-mediated platelet activation during storage. 6 PRP-platelet concentrates were subjected to adhesion analysis on collagen matrix under mild stirring condition as well as collagen-induced aggregation on day 1, 3 and 5 post-storage. Concurrently, platelet supernatants of same samples were fractionated by ultra-centrifugation and obtained micro-particle-free samples were subjected to western blot analysis for the evaluation of GPVI shedding. We showed a direct correlation between collagen-dependent platelet aggregation and adhesion (r = 0.8, p = 0.0001). The increasing levels of GPVI shedding during storage were in reverse correlation with collagen-induced platelet aggregation (r = - 0.82, p = 0.0004) which was significantly reducing during storage. Platelet adhesion to collagen matrix significantly decreased post-storage while it was also reversely correlated with the levels of GPVI shedding during 5 days storage of platelets (r = - 0.69, p = 0.002). Data presented here demonstrated that progressive shedding of surface adhesion receptor GPVI can affect its functional activities in stored platelets. Thereby considering the crucial role of GPVI in platelet adhesion to the site of injury, whether the therapeutic efficacy of banked platelet products could be influenced by storage-dependent shedding of this receptor, remains to be answered in future studies.


Assuntos
Adesividade Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Glicoproteínas da Membrana de Plaquetas/metabolismo , Bancos de Sangue/métodos , Preservação de Sangue/efeitos adversos , Colágeno/farmacologia , Humanos
12.
Transfusion ; 58(9): 2108-2112, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30160773

RESUMO

BACKGROUND: Gamma irradiation of red blood cells (RBCs) is well recognized to exacerbate storage lesion formation, but the effect of storage after irradiation on in vivo oxygen delivery capacity of transfused RBCs is currently not known. STUDY DESIGN AND METHODS: In 24 preterm infants with anemia receiving nonurgent transfusion of irradiated RBCs, we examined cerebral regional tissue oxygenation (crSO2 ) and time spent with peripheral arterial saturation (SpO2 ) less than 88%. Physiologic data were obtained immediately before, immediately after, and 5 days after transfusion. RESULTS: We observed linear negative moderate correlations between time since irradiation and the magnitude of change in crSO2 (r = -0.60; 95% CI, -0.81 to -0.27; p = 0.0018) and time spent with SpO2 of less than 88% (r = -0.42; 95% CI, -0.71 to 0.003; p = 0.04) immediately after transfusion. In infants (n = 9) who received fresher RBCs (irradiated <10 days before transfusion), there was a sustained increase in mean crSO2 up to 5 days after transfusion (3.0%; 95% CI, 0.3% to 5.7%; p = 0.04). Conversely, in infants (n = 15) who received older RBCs (irradiated ≥10 days before transfusion), there were negligible changes in crSO2 after transfusion at any time point. CONCLUSION: Our findings indicate that storage after gamma irradiation may have a detrimental effect on the oxygen delivery capacity of RBCs given to anemic preterm infants.


Assuntos
Preservação de Sangue/métodos , Transfusão de Eritrócitos , Eritrócitos/efeitos da radiação , Raios gama , Doenças do Prematuro/terapia , Oxigênio/sangue , Fatores Etários , Preservação de Sangue/efeitos adversos , Peso Corporal , Circulação Cerebrovascular , Feminino , Raios gama/efeitos adversos , Humanos , Hipóxia Encefálica/sangue , Hipóxia Encefálica/etiologia , Hipóxia Encefálica/prevenção & controle , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/sangue , Masculino , Oximetria , Pressão Parcial , Estudos Prospectivos , Espectroscopia de Luz Próxima ao Infravermelho , Fatores de Tempo
13.
Cryobiology ; 84: 59-68, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30080995

RESUMO

AIM: High glycerol cryopreservation of red blood cells (RBCs) reduces metabolic processes at ultralow temperatures but less is known regarding the effect of cryopreservation on RBC nitric oxide (NO) metabolism, haemorheological properties, structural behaviour and membrane fragility. METHODS: Blood from ten healthy participants was sampled, glycerolized and stored at -80 °C (SB). Aliquots were thawed and further processed after 4, 8 and 12 weeks, respectively. At these time points, fresh blood (FB) was additionally sampled from each participant. FB/SB mixtures were prepared corresponding to transfusion of 1-3 blood bags. Additionally, mixtures were exposed to shear stress similar to that found in the circulation and deformability was measured to estimate possible behaviour of cryopreserved RBC in vivo. RESULTS: Ageing of RBC was reduced during cryopreservation. Markers for RBC metabolism (ATP, 2,3-DPG) were not altered but RBC sodium levels increased and potassium and calcium decreased, respectively. Mean cellular volume was higher and accordingly, mean cellular haemoglobin concentration was lower in SB. Deformability was altered during storage with less shear stress necessary to deform RBCs. Changes were also detectable in blood mixtures. Deformability remained unaltered in shear stress settings in FB and SB. RBC viscosity was reduced in SB. RBC-NOS content and phosphorylation sites as well as nitrite and RxNO levels seem not to be affected by the intervention. CONCLUSION: Cryopreservation maintains RBC metabolic function in vitro, but structure and function of cryopreserved RBC seems to be altered. Impact of these alterations in vivo seems to be less but needs further investigation.


Assuntos
Preservação de Sangue/efeitos adversos , Criopreservação/métodos , Deformação Eritrocítica , Eritrócitos/metabolismo , Eritrócitos/patologia , Óxido Nítrico/metabolismo , Humanos , Reologia
14.
BMC Pediatr ; 18(1): 270, 2018 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-30098602

RESUMO

BACKGROUND: Necrotizing enterocolitis (NEC) is a leading cause of neonatal morbidity and mortality in premature infants. To date, no effective biomarkers exist to predict which premature infants will develop NEC, limiting targeted prevention strategies. Multiple observational studies have reported an association between the exposure to red blood cell (RBC) transfusion and/or anemia and the subsequent development of NEC; however, the underlying physiologic mechanisms of how these factors are independently associated with NEC remain unknown. METHODS: In this paper, we outline our prospective, multicenter observational cohort study of infants with a birth weight ≤ 1250 g to investigate the associations between RBC transfusion, anemia, intestinal oxygenation and injury that lead to NEC. Our overarching hypothesis is that irradiation of RBC units followed by longer storage perturbs donor RBC metabolism and function, and these derangements are associated with paradoxical microvascular vasoconstriction and intestinal tissue hypoxia increasing the risk for injury and/or NEC in transfused premature infants with already impaired intestinal oxygenation due to significant anemia. To evaluate these associations, we are examining the relationship between prolonged irradiation storage time (pIST), RBC metabolomic profiles, and anemia on intestinal oxygenation non-invasively measured by near-infrared spectroscopy (NIRS), and the development of NEC in transfused premature infants. DISCUSSION: Our study will address a critical scientific gap as to whether transfused RBC characteristics, such as irradiation and metabolism, impair intestinal function and/or microvascular circulation. Given the multifactorial etiology of NEC, preventative efforts will be more successful if clinicians understand the underlying pathophysiologic mechanisms and modifiable risk factors influencing the disease. TRIAL REGISTRATION: Our study is registered in ClinicalTrials.gov Identifier: NCT02741648 .


Assuntos
Preservação de Sangue/efeitos adversos , Enterocolite Necrosante/etiologia , Transfusão de Eritrócitos/efeitos adversos , Eritrócitos/efeitos da radiação , Doenças do Prematuro/terapia , Recém-Nascido de muito Baixo Peso , Anemia Neonatal/complicações , Anemia Neonatal/terapia , Preservação de Sangue/métodos , Estudos de Coortes , Eritrócitos/metabolismo , Humanos , Recém-Nascido , Doenças do Prematuro/etiologia , Oxigênio/sangue , Projetos de Pesquisa , Circulação Esplâncnica
15.
Analyst ; 143(24): 5950-5958, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30035796

RESUMO

A method to acquire the Raman spectra of sub-surface components using diffusely focused radiation in a microscope sampling configuration is described. This procedure generates Raman scattering at various sample depths by producing a converging beam at the back aperture of the objective lens. This method requires illumination of the sample with a defocused laser, while simultaneously increasing the number of CCD pixels that are binned along the spatial axis of the detector. We applied this diffuse sampling method to the analysis of stored red blood cells (RBCs). During storage, biochemical changes to RBCs occur (the "storage lesion"). However, there are no existing non-invasive methods to assess this. We evaluated the instrumental parameters needed to maximize the diffusely scattered signal, including pixel binning, slit width, and bandwidth. We demonstrated the effectiveness of this diffuse resonance Raman spectroscopy (DRRS) method by detecting RBCs through a blood bag segment (1 mm wall thickness). We directly compared the DRRS method to the more common stand-off Raman spectroscopy (SORS) method using both 633 nm and 785 nm excitation. Time-dependent DRRS spectra were used in a multivariate model for classification of RBCs in polymer segments by storage age. Young (6-8 day) RBCs were differentiated from old (35-40) RBCs with 100% sensitivity and 98.5% selectivity. These data indicated that DRRS is a promising, non-invasive technique for acquiring the spectra of sub-surface components, and is particularly applicable when the underlying sample can be resonantly enhanced.


Assuntos
Preservação de Sangue/efeitos adversos , Eritrócitos/patologia , Hemólise , Análise Espectral Raman/métodos , Hemina/química , Humanos , Análise Multivariada
16.
Trials ; 19(1): 404, 2018 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-30055634

RESUMO

BACKGROUND: The "Age of Blood in Children in Pediatric Intensive Care Unit" (ABC PICU) study is a randomized controlled trial (RCT) that aims to determine if red blood cell (RBC) unit storage age affects outcomes in critically ill children. While RBCs can be stored for up to 42 days in additive solutions, their efficacy and safety after long-term storage have been challenged. Preclinical and clinical observational evidence suggests loss of efficacy and lack of safety of older RBC units, especially in more vulnerable populations such as critically ill children. Because there is a belief that shorter storage will improve outcomes, some physicians and institutions systematically transfuse fresh RBCs to children. Conversely, the standard practice of blood banks is to deliver the oldest available RBC unit (first-in, first-out policy) in order to decrease wastage. METHODS/DESIGN: The ABC PICU study, is a double-blind superiority trial comparing the development of "New or Progressive Multiple Organ Dysfunction Syndrome" (NPMODS) in 1538 critically ill children randomized to either transfusion with RBCs stored for ≤ 7 days or to standard-issue RBCs (oldest in inventory). Patients are being recruited from 52 centers in the US, Canada, France, Italy, and Israel. DISCUSSION: The ABC PICU study should have significant implications for blood procurement services. A relative risk reduction of 33% is postulated in the short-storage arm. If a difference is found, this will indicate that fresher RBCs do improve outcomes in the pediatric intensive care unit population and would justify that use in critically ill children. If no difference is found, this will reassure clinicians and transfusion medicine specialists regarding the safety of the current system of allocating the oldest RBC unit in inventory and will discourage clinicians from preferentially requesting fresher blood for critically ill children. TRIAL REGISTRATION: ClinicalTrials.gov, ID: NCT01977547 . Registered on 6 November 2013.


Assuntos
Preservação de Sangue/métodos , Transfusão de Eritrócitos/efeitos adversos , Unidades de Terapia Intensiva Pediátrica , Insuficiência de Múltiplos Órgãos/etiologia , Adolescente , Preservação de Sangue/efeitos adversos , Preservação de Sangue/mortalidade , Canadá , Criança , Pré-Escolar , Estado Terminal , Método Duplo-Cego , Transfusão de Eritrócitos/mortalidade , Europa (Continente) , Feminino , Mortalidade Hospitalar , Humanos , Lactente , Recém-Nascido , Israel , Masculino , Estudos Multicêntricos como Assunto , Insuficiência de Múltiplos Órgãos/diagnóstico , Insuficiência de Múltiplos Órgãos/mortalidade , Insuficiência de Múltiplos Órgãos/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
17.
Lab Med ; 49(4): 298-310, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-29893945

RESUMO

Background: The therapeutic efficacy and safety of stored red blood cells (RBCs) relies on minimal in-bag hemolysis. The accuracy of current methods of measuring hemolysis can suffer as a result of specimen collection and processing artefacts. Objective: To test whether Raman spectroscopy could be used to assess hemolysis. Methods: RBCs were stored for as long as 42 days. Raman spectra of RBCs were measured before and after washing, and hemolysis was measured in supernatant by visible spectroscopy. Results: Raman spectra indicated increased concentrations of oxyhemoglobin (oxyHb) and methemoglobin (metHb), and decreased membrane fluidity with storage age. Changes in oxyHb and metHb were associated with the intraerythrocytic and extracellular fractions, respectively. Hemolysis increased in a storage age-dependent manner. Changes in Raman bands reflective of oxyHb, metHb, and RBC membranes correlated with hemolysis; the most statistically significant change was an increased intensity of metHb and decreased membrane fluidity. Conclusions: These data suggest that Raman spectroscopy may offer a new label-free modality to assess RBC hemolysis during cold storage.


Assuntos
Preservação de Sangue/efeitos adversos , Eritrócitos/citologia , Hemólise/fisiologia , Análise Espectral Raman/métodos , Testes Hematológicos , Humanos
18.
Haematologica ; 103(9): 1542-1548, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29794148

RESUMO

Observational studies address packed red blood cell effects at the end of shelf life and have larger sample sizes compared to randomized control trials. Meta-analyses combining data from observational studies have been complicated by differences in aggregate transfused packed red blood cell age and outcome reporting. This study abrogated these issues by taking a pooled patient data approach. Observational studies reporting packed red blood cell age and clinical outcomes were identified and patient-level data sets were sought from investigators. Odds ratios and 95% confidence intervals for binary outcomes were calculated for each study, with mean packed red blood cell age or maximum packed red blood cell age acting as independent variables. The relationship between mean packed red blood cell age and hospital length of stay for each paper was analyzed using zero-inflated Poisson regression. Random effects models combined paper-level effect estimates. Extremes analyses were completed by comparing patients transfused with mean packed red blood cell aged less than ten days to those transfused with mean packed red blood cell aged at least 30 days. sixteen datasets were available for pooled patient data analysis. Mean packed red blood cell age of at least 30 days was associated with an increased risk of in-hospital mortality compared to mean packed red blood cell of less than ten days (odds ratio: 3.25, 95% confidence interval: 1.27-8.29). Packed red blood cell age was not correlated to increased risks of nosocomial infection or prolonged length of hospital stay.


Assuntos
Preservação de Sangue/efeitos adversos , Transfusão de Eritrócitos/efeitos adversos , Mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Preservação de Sangue/métodos , Ensaios Clínicos como Assunto , Análise de Dados , Transfusão de Eritrócitos/métodos , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Medição de Risco , Fatores de Risco , Fatores de Tempo
19.
J Trauma Acute Care Surg ; 84(6S Suppl 1): S93-S103, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29538232

RESUMO

BACKGROUND: Damage control resuscitation principles advocate the use of blood to treat traumatic hemorrhage. Hemorrhage is a leading cause of preventable death on the battlefield, but making blood components available far forward presents logistical challenges due to shelf life and storage requirements. Whole blood simplifies logistics and enables collection in the field but can cause leukocyte-related transfusion reactions. A field-adapted leukoreduction system must be fast and safe, and storage of whole blood should preserve hemostatic function. METHODS: Blood was collected using Imuflex WB-SP and leukoreduced at 0, 150, or 300 mm Hg. Additional bags were stored at 4°C for 21 days unagitated, mixed daily, agitated or head-over-heel rotated, at 22°C for 3 days, or 32°C for 2 hours. Hematology, coagulation, CD62P/CD42b, thromboelastography (TEG)/thromboelastometry (ROTEM), and Multiplate was performed. RESULTS: Filtration time was 35 ± 1, 14 ± 0, and 9 ± 0 minutes at 0, 150, and 300 mm Hg, respectively. One of 10 units at 150 mm Hg and 4 of 11 at 300 mm Hg had residual whole blood cells greater than 5.0 × 10 per unit. One of 11 at 300 mm Hg had platelet recovery of less than 80%. Hemolysis was less than 0.2%. Filtration decreased thromboelastography/thromboelastometry and Multiplate aggregation response. Stored at 4°C, α and MA/MCF moderately decreased regardless of mixing. Significant loss of aggregation response and increased CD62P expression was seen by Day 10. By Day 3, storage at 22°C caused loss of most aggregation. Two-hour storage at 32°C did not significantly affect hemostatic capacity. CONCLUSION: Forced filtration reduced leukoreduction time, but increased residual whole blood cells reduced hemostatic function. Aggregation response deteriorated early in storage, while viscoelastic assays decreased more gradually. Mixing showed no benefits. LEVEL OF EVIDENCE: Diagnostic study, level IV.


Assuntos
Coleta de Amostras Sanguíneas , Transfusão de Sangue/métodos , Hemostasia , Procedimentos de Redução de Leucócitos , Contagem de Células Sanguíneas , Preservação de Sangue/efeitos adversos , Preservação de Sangue/métodos , Coleta de Amostras Sanguíneas/efeitos adversos , Exsanguinação/terapia , Feminino , Flores , Hematócrito , Hemofiltração/métodos , Hemoglobinas/análise , Temperatura Alta/efeitos adversos , Humanos , Procedimentos de Redução de Leucócitos/métodos , Masculino , Medicina Militar/métodos , Agregação Plaquetária , Tromboelastografia
20.
Transfusion ; 58(6): 1486-1493, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29577324

RESUMO

BACKGROUND: Red blood cell (RBC) transfusion has been related to thromboembolic events. Microvesicles in the RBC product may support coagulation because they have procoagulant effects in vitro. We investigated whether transfusion of RBCs containing extracellular vesicles promotes coagulation in human recipients. As transfusion is mostly administered to ill patients, we used a model of endotoxemia. STUDY DESIGN AND METHODS: Eighteen healthy volunteers were randomized to receive either saline or fresh (2 days stored) or stored autologous (35 days stored) RBC transfusion (Dutch Trial Register: NTR4455). Two hours after infusion of lipopolysaccharide (LPS, from Escherichia coli, 2 ng/kg body weight), subjects received either saline or fresh or stored RBCs. Blood was sampled every 2 hours up to 8 hours after LPS infusion. Vesicles were measured with a flow cytometer (A50-Micro, Apogee Flow Systems). RESULTS: LPS resulted in increased thrombin generation compared to baseline. During storage, the total number of extracellular vesicles increased from 1.4 × 108 /mL (interquartile range [IQR], 8.3 × 107 -1.9 × 108 /mL) in the fresh product to 1.7 × 1010 /mL (IQR, 7.9 × 109 -2.3 × 1010 /mL; p < 0.01) in the stored product (p < 0.001). Vesicles appeared to be mostly RBC derived. CONCLUSION: After transfusion, extracellular vesicles from stored RBC products, but not from fresh products, could be detected in the circulation of healthy volunteers. However, infusion of stored RBC extracellular vesicles did not augment thrombin generation compared to endotoxemic controls. Also, levels of d-dimer and thrombin-antithrombin complex were unaffected. In conclusion, transfusion of autologous RBCs containing high levels of extracellular vesicles does not enhance coagulation in human volunteers with endotoxemia.


Assuntos
Endotoxemia/sangue , Transfusão de Eritrócitos/métodos , Vesículas Extracelulares/transplante , Adulto , Coagulação Sanguínea , Preservação de Sangue/efeitos adversos , Endotoxemia/induzido quimicamente , Transfusão de Eritrócitos/efeitos adversos , Voluntários Saudáveis , Humanos , Lipopolissacarídeos , Transplante Autólogo
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