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1.
Am J Vet Res ; 80(6): 578-585, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31140844

RESUMO

OBJECTIVE: To evaluate stability of coagulation factors in canine plasma obtained by use of plasmapheresis and stored over a 36-month period. SAMPLE: Canine plasma obtained by use of plasmapheresis acquired from a commercial blood bank. PROCEDURES: Coagulation testing for fibrinogen concentration and activity of factors II, V, VII, VIII, and IX and von Willebrand factor was performed on canine plasma obtained by use of plasmapheresis. Samples were obtained for testing at 6-month intervals from plasma stored for up to 36 months. RESULTS: A simple mixed linear regression model was created for each analysis. Median value for the fibrinogen concentration was > 150 mg/dL for all time points, except at 467, 650, and 1,015 days of storage. Median value for factor VIII was > 70% only at 650 days. Median value for factor V was > 50% through 650 days. Median value for factors VII and X was > 50% through 833 days, and median value for factors II and VII was > 50% through 1,015 days. Median value for von Willebrand factor was > 50% for the entire study (1,198 days). Median value for factor X was always < 50%. CONCLUSIONS AND CLINICAL RELEVANCE: Coagulation factors degraded over time at variable rates, and all labile factors remained at > 50% activity for longer than 1 year. Plasma collected by plasmapheresis potentially offers prolonged life span of some clotting factors. Plasmapheresis is an acceptable form of canine plasma collection for transfusion purposes, and further studies should be performed to determine all of its benefits.


Assuntos
Fatores de Coagulação Sanguínea , Cães/sangue , Plasmaferese/veterinária , Animais , Fatores de Coagulação Sanguínea/isolamento & purificação , Fatores de Coagulação Sanguínea/metabolismo , Testes de Coagulação Sanguínea/veterinária , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Fibrinogênio/metabolismo , Plasma/química , Fatores de Tempo , Fator de von Willebrand/metabolismo
2.
Biosens Bioelectron ; 131: 128-135, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30826647

RESUMO

This article is clearly presenting the development of a biosensor for human factor IX (FIX) to diagnose the blood clotting deficiency, a so-called 'Royal disease' using an interdigitated electrode (IDE) with the zinc oxide surface modification. Gold nano-urchins (GNUs) with 60 nm in diameter was integrated into a streptavidin-biotinylated aptamer strategy to enhance the active surface area. Two different comparative studies have been done to validate the system to be practiced in the current work holds with a higher capability for the high-performance sense. Whereby, the presence and absence of GNUs in the aptasensing system for FIX interaction were investigated using the amperometric measurement, using a linear sweep voltage of 0-2 V at 0.01 V step voltage. The detection limit was 6 pM based on 3σ calculation when GNUs integrated aptamer assay was utilized for FIX detection, which shows 8 folds sensitivity enhancement comparing the condition in the absence of GNU and 50 folds higher than sensitive radio-isotope and surface plasmon resonance assays. Albeit, the surface and molecular characterizations were well demonstrated by scanning electron microscopy, atomic force microscopy, 3D nano-profilometry and further supports were rendered by UV-Vis spectroscopy and Enzyme-linked apta-sorbent assay (ELASA). Furthermore, the spiking experiment was done by FIX-spikes in human blood serum in order to demonstrate the stability with a higher non-fouling.


Assuntos
Técnicas Biossensoriais , Fatores de Coagulação Sanguínea/isolamento & purificação , Coagulação Sanguínea/genética , Fator IX/isolamento & purificação , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Fatores de Coagulação Sanguínea/química , Eletrodos , Fator IX/química , Ouro/química , Humanos , Limite de Detecção , Prognóstico , Estreptavidina/química , Ressonância de Plasmônio de Superfície
3.
Sci Rep ; 8(1): 6210, 2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29670183

RESUMO

The harnessing of medicinal plants containing a plethora of bioactive molecules may lead to the discovery of novel, potent and safe therapeutic agents to treat thrombosis-associated cardiovascular diseases. A 35 kDa (m/z 34747.5230) serine protease (lunathrombase) showing fibrin(ogen)olytic activity and devoid of N- and O- linked oligosaccharides was purified from an extract of aqueous leaves from L. indica. The LC-MS/MS analysis, de novo sequencing, secondary structure, and amino acid composition determination suggested the enzyme's novel characteristic. Lunathrombase is an αß-fibrinogenase, demonstrating anticoagulant activity with its dual inhibition of thrombin and FXa by a non-enzymatic mechanism. Spectrofluorometric and isothermal calorimetric analyses revealed the binding of lunathrombase to fibrinogen, thrombin, and/or FXa with the generation of endothermic heat. It inhibited collagen/ADP/arachidonic acid-induced mammalian platelet aggregation, and demonstrated antiplatelet activity via COX-1 inhibition and the upregulation of the cAMP level. Lunathrombase showed in vitro thrombolytic activity and was not inhibited by endogenous protease inhibitors α2 macroglobulin and antiplasmin. Lunathrombase was non-cytotoxic to mammalian cells, non-hemolytic, and demonstrated dose-dependent (0.125-0.5 mg/kg) in vivo anticoagulant and plasma defibrinogenation activities in a rodent model. Lunathrombase (10 mg/kg) did not show toxicity or adverse pharmacological effects in treated animals.


Assuntos
Anticoagulantes/farmacologia , Fibrinolíticos/farmacologia , Lamiaceae/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Serina Proteases/farmacologia , Animais , Anticoagulantes/química , Anticoagulantes/isolamento & purificação , Fatores de Coagulação Sanguínea/química , Fatores de Coagulação Sanguínea/isolamento & purificação , Fatores de Coagulação Sanguínea/farmacologia , AMP Cíclico , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Fibrinólise/efeitos dos fármacos , Fibrinolíticos/química , Fibrinolíticos/isolamento & purificação , Hemólise/efeitos dos fármacos , Oligossacarídeos/química , Peptídeos/química , Peptídeos/isolamento & purificação , Peptídeos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/isolamento & purificação , Inibidores da Agregação Plaquetária/farmacologia , Serina Proteases/química , Serina Proteases/isolamento & purificação , Análise Espectral
4.
Int J Mol Sci ; 19(1)2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29286309

RESUMO

Plasma extracellular vesicles (EVs) are lipid membrane vesicles involved in several biological processes including coagulation. Both coagulation and lipid metabolism are strongly associated with cardiovascular events. Lowering very-low- and low-density lipoprotein ((V)LDL) particles via dextran sulphate LDL apheresis also removes coagulation proteins. It remains unknown, however, how coagulation proteins are removed in apheresis. We hypothesize that plasma EVs that contain high levels of coagulation proteins are concomitantly removed with (V)LDL particles by dextran sulphate apheresis. For this, we precipitated (V)LDL particles from human plasma with dextran sulphate and analyzed the abundance of coagulation proteins and EVs in the precipitate. Coagulation pathway proteins, as demonstrated by proteomics and a bead-based immunoassay, were over-represented in the (V)LDL precipitate. In this precipitate, both bilayer EVs and monolayer (V)LDL particles were observed by electron microscopy. Separation of EVs from (V)LDL particles using density gradient centrifugation revealed that almost all coagulation proteins were present in the EVs and not in the (V)LDL particles. These EVs also showed a strong procoagulant activity. Our study suggests that dextran sulphate used in LDL apheresis may remove procoagulant EVs concomitantly with (V)LDL particles, leading to a loss of coagulation proteins from the blood.


Assuntos
Fatores de Coagulação Sanguínea/isolamento & purificação , Remoção de Componentes Sanguíneos/efeitos adversos , Lipoproteínas LDL/química , Lipoproteínas VLDL/química , Adsorção , Adulto , Sulfato de Dextrana/química , Feminino , Humanos , Lipoproteínas LDL/isolamento & purificação , Lipoproteínas VLDL/isolamento & purificação , Masculino
5.
Biochemistry ; 56(6): 896-902, 2017 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-28098450

RESUMO

The pentraxin serum amyloid P component (SAP) is secreted by the liver and found in plasma at a concentration of approximately 30 mg/L. SAP is a 25 kDa homopentamer known to bind both protein and nonprotein ligands, all in a calcium-dependent manner. The function of SAP is unclear but likely involves the humoral innate immune system spanning the complement system, inflammation, and coagulation. Also, SAP is known to bind to the generic structure of amyloid deposits and possibly to protect them against proteolysis. In this study, we have characterized the SAP interactome in human plasma containing the physiological Ca2+ concentration using SAP affinity pull-down and co-immunoprecipitation experiments followed by mass spectrometry analyses. The analyses resulted in the identification of 33 proteins, of which 24 were direct or indirect interaction partners not previously reported. The SAP interactome can be divided into categories that include apolipoproteins, the complement system, coagulation, and proteolytic regulation.


Assuntos
Proteínas Sanguíneas/metabolismo , Cálcio/sangue , Imunidade Inata , Componente Amiloide P Sérico/metabolismo , Adulto , Anticorpos Imobilizados/metabolismo , Anticorpos Monoclonais/metabolismo , Antitrombinas/farmacologia , Apolipoproteínas/sangue , Apolipoproteínas/química , Apolipoproteínas/isolamento & purificação , Apolipoproteínas/metabolismo , Fatores de Coagulação Sanguínea/análise , Fatores de Coagulação Sanguínea/química , Fatores de Coagulação Sanguínea/isolamento & purificação , Fatores de Coagulação Sanguínea/metabolismo , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/química , Proteínas Sanguíneas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Proteínas do Sistema Complemento/análise , Proteínas do Sistema Complemento/química , Proteínas do Sistema Complemento/isolamento & purificação , Proteínas do Sistema Complemento/metabolismo , Feminino , Hirudinas/farmacologia , Humanos , Imunoprecipitação , Ligantes , Masculino , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Proteólise , Proteínas Recombinantes/farmacologia , Componente Amiloide P Sérico/análise , Componente Amiloide P Sérico/antagonistas & inibidores , Componente Amiloide P Sérico/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
6.
Transfus Clin Biol ; 22(3): 85-9, 2015 Aug.
Artigo em Francês | MEDLINE | ID: mdl-25933512

RESUMO

Until 1990, congenital hemorrhagic disorders were treated by plasma-derived concentrates. The first recombinant drug, recombinant factor VIII was available after this date and few years later recombinant factor IX could also be proposed to patients. The evolution of market share in France was different between these two drugs: while recombinant factor VIII took a large place in hemophilia A treatment (85%), plasma-derived factor IX represent 50% of the French market. In the next years, the arrival of long-acting antihemophilic factors may lead to the dramatically reduce the amount of plasma-derived antihemophilic factors used to treat hemophilia. For rare bleeding coagulation disorders, plasma-derived concentrates are still widely used, while they are the only concentrates available in most diseases. This situation is unlikely to evolve significantly in the next years.


Assuntos
Fatores de Coagulação Sanguínea/uso terapêutico , Transtornos Hemorrágicos/tratamento farmacológico , Proteínas Recombinantes/uso terapêutico , Animais , Animais Geneticamente Modificados , Fatores de Coagulação Sanguínea/genética , Fatores de Coagulação Sanguínea/isolamento & purificação , Fatores de Coagulação Sanguínea/provisão & distribuição , Uso de Medicamentos , Feminino , Previsões , França/epidemiologia , Transtornos Hemorrágicos/epidemiologia , Humanos , Plasma , Prevalência , Coelhos , Proteínas Recombinantes/provisão & distribuição
7.
Biologicals ; 42(5): 260-70, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25096922

RESUMO

Polyvalent immunoglobulin G (IgG) products obtained by fractionation of human plasma are used to treat a broad range of conditions, including immunodeficiency syndromes and autoimmune, inflammatory, and infectious diseases. Recent incidences of increased thromboembolic events (TEEs) associated with intravenous (IV) IgG (IVIG) led to recalls of some products and increased regulatory oversight of manufacturing processes in order to ensure that products are essentially free of procoagulant/thrombogenic plasma protein contaminants. Laboratory investigations have now identified activated factor XI (FXIa) as the likely causative agent of IVIG-related TEEs. Quantification of the thrombogenic potential is becoming a requirement made to fractionators (a) to validate the capacity of IVIG and subcutaneous IgG manufacturing processes to remove procoagulant contaminants and (b) to establish the safety of the final products. However, in the absence of a recommended test by the main regulatory authorities, several analytical approaches have been evaluated by fractionators, regulators, and university groups. This review focuses on the scientific rationale, merits, and applications of several analytical methods of quantifying the thrombogenic potential of IgG products and intermediates to meet the latest regulatory requirements.


Assuntos
Produtos Biológicos/efeitos adversos , Produtos Biológicos/sangue , Imunoglobulina G/efeitos adversos , Imunoglobulina G/sangue , Tromboembolia/etiologia , Animais , Produtos Biológicos/normas , Fatores de Coagulação Sanguínea/efeitos adversos , Fatores de Coagulação Sanguínea/isolamento & purificação , Química Farmacêutica , Contaminação de Medicamentos/prevenção & controle , Fator XIa/efeitos adversos , Fator XIa/isolamento & purificação , Humanos , Imunoglobulinas Intravenosas/efeitos adversos , Imunoglobulinas Intravenosas/normas , Fatores Imunológicos/efeitos adversos , Fatores Imunológicos/sangue , Medição de Risco , Tromboembolia/sangue , Tromboembolia/imunologia
9.
Transfusion ; 52(10): 2122-30, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22339168

RESUMO

BACKGROUND: Chikungunya virus (CHIKV) outbreaks were previously restricted to parts of Africa, Indian Ocean Islands, South Asia, and Southeast Asia. In 2007, however, the first autochthonous CHIKV transmission was reported in Europe. High-level viremia, a mosquito vector that is also present in large urban areas of Europe and America, and uncertainty around the resistance of this Alphavirus toward physiochemical inactivation processes raised concerns about the safety of plasma derivatives. To verify the safety margins of plasma products with respect to CHIKV, commonly used virus inactivation steps were investigated for their effectiveness to inactivate this newly emerging virus. STUDY DESIGN AND METHODS: Pasteurization for human serum albumin (HSA), vapor heating for Factor VIII inhibitor bypassing activity, solvent/detergent (S/D) treatment for intravenous immunoglobulin (IVIG), and incubation at low pH for IVIG were investigated for their capacity to inactivate CHIKV and the closely related Sindbis virus (SINV). The obtained results were compared to previous studies with West Nile virus and the commonly used model virus bovine viral diarrhea virus. RESULTS: The data generated demonstrate the effective inactivation of CHIKV as well as SINV by the inactivation steps investigated and thereby support results from earlier validation studies in which model viruses were used. CONCLUSION: High inactivation capacities with respect to CHIKV were demonstrated. This provides solid reassurance for the safety of plasma products and the results verify that the use of model viruses is appropriate to predict the inactivation characteristics of newly emerging viruses when their physicochemical properties are well characterized.


Assuntos
Infecções por Alphavirus/prevenção & controle , Fatores de Coagulação Sanguínea/isolamento & purificação , Segurança do Sangue , Vírus Chikungunya/isolamento & purificação , Imunoglobulinas Intravenosas/isolamento & purificação , Plasma/virologia , Albumina Sérica/isolamento & purificação , Inativação de Vírus , Ácidos/farmacologia , Idoso , Infecções por Alphavirus/sangue , Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/transmissão , Animais , Linhagem Celular/virologia , Vírus Chikungunya/efeitos dos fármacos , Vírus Chikungunya/crescimento & desenvolvimento , Doenças Transmissíveis Emergentes/prevenção & controle , Detergentes/farmacologia , Surtos de Doenças , Liofilização , Saúde Global , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Pasteurização , Sindbis virus/efeitos dos fármacos , Sindbis virus/crescimento & desenvolvimento , Sindbis virus/isolamento & purificação , Tensoativos/farmacologia , Carga Viral , Viremia/virologia , Vírus do Nilo Ocidental/efeitos dos fármacos , Vírus do Nilo Ocidental/crescimento & desenvolvimento , Vírus do Nilo Ocidental/isolamento & purificação
10.
Tissue Eng Part C Methods ; 18(3): 176-85, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21951067

RESUMO

Platelet-rich plasma (PRP) has been clinically used as an easily prepared growth factor cocktail that can promote wound healing, angiogenesis, and tissue remodeling. However, the therapeutic effects of PRP are still controversial, due partly to the lack of optimized and standardized preparation protocols. We used whole blood (WB) samples to optimize the preparation protocols for PRP, white blood cell-containing (W-PRP), platelet-concentrated plasma (PCP), and noncoagulating platelet-derived factor concentrate (PFC). PRP and W-PRP were most efficiently collected by 10 min centrifugation in a 15-mL conical tube at 230-270 g and 70 g, respectively. To prepare PCP, platelets were precipitated by centrifugation of PRP at >2300 g, 90% of supernatant plasma was removed, and the platelets were resuspended. For preparation of noncoagulating PFC, the supernatant was replaced with one-tenth volume of saline, followed by platelet activation with thrombin. Platelet (before activation) and platelet-derived growth factor (PDGF)-BB (after activation) concentrations in PCP were approximately 20 times greater than those in WB, whereas PFC contained a 20-times greater concentration of platelets before platelet activation and a 50-times greater concentration of PDGF-BB without formation of a fibrin gel after platelet activation than WB. Surprisingly, total PDGF-BB content in the PFC was twice that of activated WB, which suggested that a substantial portion of the PDGF-BB became trapped in the fibrin glue, and replacement of plasma with saline is crucial for maximization of platelet-derived factors. As an anticoagulant, ethylene di-amine tetra-acetic acid disodium inhibited platelet aggregation more efficiently than acid citrate dextrose solution, resulting in higher nonaggregated platelet yield and final PDGF-BB content. These results increase our understanding of how to optimize and standardize preparation of platelet-derived factors at maximum concentrations.


Assuntos
Remoção de Componentes Sanguíneos/normas , Plaquetas/química , Fibrinogênio/isolamento & purificação , Fator de Crescimento Derivado de Plaquetas/isolamento & purificação , Plasma Rico em Plaquetas , Adulto , Fatores de Coagulação Sanguínea/isolamento & purificação , Fatores de Coagulação Sanguínea/metabolismo , Remoção de Componentes Sanguíneos/métodos , Plaquetas/metabolismo , Calibragem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Contagem de Plaquetas , Fator de Crescimento Derivado de Plaquetas/análise , Fator de Crescimento Derivado de Plaquetas/metabolismo , Plasma Rico em Plaquetas/química , Plasma Rico em Plaquetas/metabolismo , Plasma Rico em Plaquetas/fisiologia
11.
Transfusion ; 51 Suppl 1: 50S-57S, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21223296

RESUMO

BACKGROUND: There is increasing international interest in producing components from blood that has been stored at room temperature for 24 hours. The lack of comprehensive data on the quality of plasma produced from blood stored in this way led to this international study. STUDY DESIGN AND METHODS: A total of 128 units of whole blood were pooled in groups of four and split to produce 32 sets of four identical blood units that were processed either within 8 hours of blood collection or after 24-hour storage at 18 to 25°C. RESULTS: Storage of whole blood for 24 hours resulted in a 23% decrease in the activity of Factor (F)VIII, but not significant loss of activity of coagulation factors FV, FVII, FXI, FXII, fibrinogen, antithrombin, or von Willebrand factor. There was a small, but significant decrease in levels of FII, FIX, and FX (all <5%) as well as protein C (6%) and free protein S activity (14%). The ability of plasma to generate thrombin after 24-hour storage as whole blood was unaltered, as assessed by real-time thrombin generation tests as was the rate and strength of clot formation by rotational thombelastometry. Levels of all coagulation factors measured were above 0.50 U/mL in plasma produced from whole blood stored for 24 hours. CONCLUSION: These data show that there is minimal effect of storing whole blood at ambient temperature for 24 hours on the coagulation activity of plasma and that this is an acceptable alternative to producing plasma on the day of blood collection.


Assuntos
Fatores de Coagulação Sanguínea/análise , Remoção de Componentes Sanguíneos/métodos , Preservação de Sangue/métodos , Sistema ABO de Grupos Sanguíneos/análise , Fatores de Coagulação Sanguínea/isolamento & purificação , Sistemas Computacionais , Fator VIII/análise , Feminino , Hemostasia , Humanos , Procedimentos de Redução de Leucócitos , Masculino , Tempo de Tromboplastina Parcial , Plasma , Estabilidade Proteica , Tempo de Protrombina , Temperatura , Tromboelastografia , Trombina/biossíntese , Fatores de Tempo
12.
Transfusion ; 51 Suppl 1: 58S-64S, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21223297

RESUMO

BACKGROUND: The quality of blood components prepared from whole blood (WB) units rapidly cooled to 20 to 24°C and stored for prolonged periods using butane-1,4-diol "cooling plates," and the factors that determine the functional activity of these cooling systems under various temperature conditions were investigated. STUDY DESIGN AND METHODS: Validation of the cooling systems functions, performed in different environmental temperature-time schemes using WB-mock units, were recorded and analyzed in 106 temperature curves, simulating environmental conditions of blood storage at the blood drives and transport to the blood services component laboratory. The quality of red blood cells, fresh-frozen plasma, platelet concentrates, and cryoprecipitate units was studied on components routinely prepared in 2007 to 2009 from WB units collected in citrate-phosphate-dextrose-adenine or citrate-phosphate-dextrose (CPD), rapidly cooled, and stored in ambient temperature for up to 22 hours postdonation using the cooling systems. RESULTS: Quality variables of blood components prepared from WB units rapidly cooled and held overnight for up to 22 hours postcollection, using both cooling systems, met the allowed ranges of American, European, and Israeli standards. Temperature validation of the cooling systems resulted in national standard operating procedures for the proper use in different ambient temperature ranges. CONCLUSION: The rapid cooling of WB and prolonged storage under different environmental conditions using cooling plate systems enabled standardization of blood storage at and transportation from all collection sites. It provided an efficient, reproducible, and cost-effective way to ensure good quality blood components, while utilizing more efficient logistic and administrative means.


Assuntos
Fatores de Coagulação Sanguínea/análise , Remoção de Componentes Sanguíneos/métodos , Preservação de Sangue/métodos , Refrigeração/métodos , Bancos de Sangue/normas , Análise Química do Sangue , Fatores de Coagulação Sanguínea/isolamento & purificação , Remoção de Componentes Sanguíneos/economia , Preservação de Sangue/economia , Preservação de Sangue/normas , Análise Custo-Benefício , Estudos de Viabilidade , Hemólise , Humanos , Israel , Procedimentos de Redução de Leucócitos , Unidades Móveis de Saúde , Controle de Qualidade , Refrigeração/economia , Refrigeração/normas , Reprodutibilidade dos Testes , Temperatura , Fatores de Tempo , Meios de Transporte
13.
Contrib Nephrol ; 165: 322-328, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20427984

RESUMO

Sepsis is one of the main causes of death in critically ill patients. The pathophysiology of sepsis is complex and not completely understood. The proinflammatory and anti-inflammatory response leads to cell and organ dysfunction and, in many cases, death. Thus, the goal of the intervention is to restore the homeostasis of circulating mediators rather than to inhibit selectively the proinflammatory or anti-inflammatory mediators. Blood purification has been reported to remove a wide array of inflammatory mediators. The effects are broad-spectrum and auto-regulating. Blood purification has also been demonstrated to restore immune function through improving antigen-presenting capability, adjusting leukocyte recruitment, oxidative burst and phagocytosis, and improving leukocyte responsiveness. A great deal of work has to be done in order to find and optimize the best extracorporeal blood purification therapy for sepsis. New devices specifically target the pathophysiological mechanisms involved in these conditions. High-volume hemofiltration, hemoadsorption, coupled plasma filtration adsorption, and high cutoff membrane are now being tested in septic patients. Preliminary data indicate the feasibility of these modified techniques in sepsis. Their impact on patient prognosis, however, still needs proof by large randomized clinical trials. Finally, the emerging paradigm of sepsis-induced immune suppression provides additional rationale for the development of extracorporeal blood purification therapy for sepsis.


Assuntos
Hemofiltração/métodos , Sepse/terapia , Fatores de Coagulação Sanguínea/isolamento & purificação , Causas de Morte , Quimiocinas/sangue , Quimiocinas/isolamento & purificação , Proteínas do Sistema Complemento/isolamento & purificação , Estado Terminal , Citocinas/sangue , Citocinas/isolamento & purificação , Humanos , Inflamação/sangue , Mediadores da Inflamação/sangue , Mediadores da Inflamação/isolamento & purificação , Sepse/etiologia , Sepse/mortalidade , Sepse/fisiopatologia , Choque Séptico/etiologia , Choque Séptico/mortalidade , Choque Séptico/fisiopatologia , Choque Séptico/terapia
14.
Anal Biochem ; 399(1): 102-9, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19995544

RESUMO

Current plasma fractionation technology combines ethanol precipitation with packed bed chromatography. We have developed a novel core fractionation process comprising five expanded bed adsorption (EBA) chromatographic steps on high-density modified agarose/tungsten carbide beads. Plasma was first chromatographed on two diethyl amino-ethyl (DEAE)-tungsten carbide agarose adsorbents (respective mean particle diameters of d(v)(0.5)=190 and 37 microm) to isolate at 50 to 80% recovery a fraction containing 4 to 7 IU/ml factor II (FII), factor IX (FIX), and factor X (FX) (specific activity >1 IU/mg) and another enriched in FVIII and von Willebrand factor (vWF) (approximately 1 IU/ml and 0.6 IU/mg, respectively). The flow-through was adsorbed on 4% agarose-10% tungsten carbide beads coupled with an acidic mixed-mode ligand to isolate an 80% pure immunoglobulin G (IgG) at a 93% step recovery. A highly purified alpha1-antitrypsin was isolated at 95% step recovery by adsorbing the flow-through on 4% epoxy-crosslinked agarose-10% tungsten carbide adsorbent material coupled with a cationic ligand. Isolation of 98% pure albumin was achieved at a 99% step recovery by pH 4.5 adsorption of the flow-through on 6% agarose-10% tungsten carbide beads coupled with an acidic mixed-mode ligand. EBA may represent a feasible alternative core plasma fractionation tool.


Assuntos
Proteínas Sanguíneas/isolamento & purificação , Cromatografia em Gel/métodos , Fatores de Coagulação Sanguínea/isolamento & purificação , Fracionamento Químico , Etanol/química , Fator VIII/isolamento & purificação , Humanos , Imunoglobulina G/isolamento & purificação , Albumina Sérica/isolamento & purificação , Compostos de Tungstênio/química , alfa 1-Antitripsina/isolamento & purificação , Fator de von Willebrand/isolamento & purificação
15.
J Proteomics ; 73(3): 678-88, 2010 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-19819359

RESUMO

The use of proteomic techniques in the monitoring of different production steps of plasma-derived clotting factor IX (pd F IX) was demonstrated. The first step, solid-phase extraction with a weak anion-exchange resin, fractionates the bulk of human serum albumin (HSA), immunoglobulin G, and other non-binding proteins from F IX. The proteins that strongly bind to the anion-exchange resin are eluted by higher salt concentrations. In the second step, anion-exchange chromatography, residual HSA, some proteases and other contaminating proteins are separated. In the last chromatographic step, affinity chromatography with immobilized heparin, the majority of the residual impurities are removed. However, some contaminating proteins still remain in the eluate from the affinity column. The next step in the production process, virus filtration, is also an efficient step for the removal of residual impurities, mainly high molecular weight proteins, such as vitronectin and inter-alpha inhibitor proteins. In each production step, the active component, pd F IX and contaminating proteins are monitored by biochemical and immunochemical methods and by LC-MS/MS and their removal documented. Our methodology is very helpful for further process optimization, rapid identification of target proteins with relatively low abundance, and for the design of subsequent steps for their removal or purification.


Assuntos
Fator IX/isolamento & purificação , Plasma/química , Proteômica/métodos , Estudos de Validação como Assunto , Resinas de Troca Aniônica/química , Resinas de Troca Aniônica/farmacologia , Fatores de Coagulação Sanguínea/análise , Fatores de Coagulação Sanguínea/isolamento & purificação , Cromatografia de Afinidade/métodos , Cromatografia em Agarose/métodos , Técnicas de Laboratório Clínico , DEAE-Dextrano/química , DEAE-Dextrano/farmacologia , Fator IX/análise , Fator IX/metabolismo , Hemofiltração/métodos , Heparina/metabolismo , Humanos , Extração em Fase Sólida/métodos
16.
Protein Expr Purif ; 64(2): 194-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19041722

RESUMO

Endothelial cell protein C receptor (EPCR) downregulates the coagulation system and prevents thrombosis by binding to protein C/activated protein C (APC) and factor VII/activated factor VII (VIIa). Recombinant APC and factor VIIa have been shown to be useful in a variety of clinical conditions. Murine models could prove extremely helpful in order to study in vivo actions of these drugs. It is therefore crucial to demonstrate the interaction between these and murine EPCR. We expressed the extracellular region of the murine EPCR in a yeast expression system and obtained a colony of Pichia pastoris that produce high amounts of recombinant extracellular murine EPCR, which we purified by liquid chromatography to homogeneity. The analysis of the interaction of EPCR with APC and factor VIIa was carried out using surface plasmon resonance technology. Murine EPCR binds to APC and factor VIIa with similar affinity than human EPCR. As for human EPCR, the binding is Ca2+ dependent while Mg2+ ions optimize it. In conclusion, we succeeded in establishing a system to produce enough recombinant soluble murine EPCR to perform biochemical studies. Murine EPCR binds to human APC and factor VIIa, which opens up new possibilities for characterizing the in vivo effect of APC and factor VII by using murine models.


Assuntos
Fatores de Coagulação Sanguínea/genética , Pichia/metabolismo , Receptores de Superfície Celular/genética , Proteínas Recombinantes/genética , Animais , Sítios de Ligação , Fatores de Coagulação Sanguínea/isolamento & purificação , Fatores de Coagulação Sanguínea/metabolismo , Cromatografia Líquida , Fator VIIa/metabolismo , Humanos , Camundongos , Pichia/genética , Proteína C/metabolismo , Receptores de Superfície Celular/isolamento & purificação , Receptores de Superfície Celular/metabolismo , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
17.
Blood Transfus ; 6 Suppl 2: s21-5, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19105506

RESUMO

Haemophilia patients may require prolonged treatment during peri-operative period or life-threatening bleedings. Intermittent bolus infusions of factor concentrates have been used successfully for many years. However, pharmacokinetics may vary among products and patients, and the wide fluctuations in factor levels during therapy can make management inaccurate and unsafe. Specific protocols for continuous infusion have been developed, which may decrease factor utilization, facilitate laboratory monitoring of factor levels, and may decrease the overall cost of therapy. Continuous infusion of different clotting factor concentrates (factor VIII, factor IX, porcine factor VIII, rFVIIa, and activated prothrombin complex concentrates) has been associated with excellent haemostasis and safety: indeed, by continuous infusion unsafe low troughs or dangerous high concentrations can be avoided. In this review, the pharmacokinetic aspects of the continuous infusion of plasma-derived and recombinant factor IX concentrates are showed. Finally, the advantages and disadvantages of continuous infusion are discussed.


Assuntos
Fatores de Coagulação Sanguínea/administração & dosagem , Fator IX/administração & dosagem , Hemofilia B/tratamento farmacológico , Hemorragia/prevenção & controle , Fatores de Coagulação Sanguínea/imunologia , Fatores de Coagulação Sanguínea/isolamento & purificação , Fatores de Coagulação Sanguínea/farmacocinética , Fatores de Coagulação Sanguínea/uso terapêutico , Perda Sanguínea Cirúrgica/prevenção & controle , Cateterismo Venoso Central , Ensaios Clínicos como Assunto/estatística & dados numéricos , Fator IX/isolamento & purificação , Fator IX/farmacocinética , Fator IX/uso terapêutico , Meia-Vida , Hemofilia B/complicações , Humanos , Infusões Intravenosas , Isoanticorpos/biossíntese , Taxa de Depuração Metabólica , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Plasma , Hemorragia Pós-Operatória/prevenção & controle , Estudos Prospectivos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapêutico , Prevenção Secundária
18.
J Trauma ; 64(5): 1211-7; discussion 1217, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18469643

RESUMO

BACKGROUND: Coagulopathy is present at admission in 25% of trauma patients, is associated with shock and a 5-fold increase in mortality. The coagulopathy has recently been associated with systemic activation of the protein C pathway. This study was designed to characterize the thrombotic, coagulant and fibrinolytic derangements of trauma-induced shock. METHODS: This was a prospective cohort study of major trauma patients admitted to a single trauma center. Blood was drawn within 10 minutes of arrival for analysis of partial thromboplastin and prothrombin times, prothrombin fragments 1 + 2 (PF1 + 2), fibrinogen, factor VII, thrombomodulin, protein C, plasminogen activator inhibitor-1 (PAI-1), thrombin activatable fibrinolysis inhibitor (TAFI), tissue plasminogen activator (tPA), and D-dimers. Base deficit was used as a measure of tissue hypoperfusion. RESULTS: Two hundred eight patients were studied. Systemic hypoperfusion was associated with anticoagulation and hyperfibrinolysis. Coagulation was activated and thrombin generation was related to injury severity, but acidosis did not affect Factor VII or PF1 + 2 levels. Hypoperfusion-induced increase in soluble thrombomodulin levels was associated with reduced fibrinogen utilization, reduction in protein C and an increase in TAFI. Hypoperfusion also resulted in hyperfibrinolysis, with raised tPA and D-Dimers, associated with the observed reduction in PAI-1 and not alterations in TAFI. CONCLUSIONS: Acute coagulopathy of trauma is associated with systemic hypoperfusion and is characterized by anticoagulation and hyperfibrinolysis. There was no evidence of coagulation factor loss or dysfunction at this time point. Soluble thrombomodulin levels correlate with thrombomodulin activity. Thrombin binding to thrombomodulin contributes to hyperfibrinolysis via activated protein C consumption of PAI-1.


Assuntos
Fatores de Coagulação Sanguínea/isolamento & purificação , Coagulação Intravascular Disseminada/sangue , Ferimentos e Lesões/sangue , Coagulação Intravascular Disseminada/etiologia , Fibrinólise , Humanos , Escala de Gravidade do Ferimento , Estudos Prospectivos , Proteína C/metabolismo , Centros de Traumatologia , Ferimentos e Lesões/classificação , Ferimentos e Lesões/complicações
19.
Thromb Haemost ; 99(5): 851-62, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18449414

RESUMO

Several biological medicines derived from human and animal plasmas can effectively improve haemostasis in individuals with inherited or acquired defects in haemostasis. Factor VIII and factor VIII/vWF and factor IX concentrates are used to treat haemophilia A, von Willebrand disease and hemophilia B respectively. Cryoprecipitates are used to treat hypofibrinogenemia and von Willebrand disease where desmopressin (DDAVP) is ineffective or when plasma-derived factor VIII/vWF concentrates are unavailable. Thrombin-containing topical haemostatic agents and fibrin sealants are used to control perioperative bleeding. Intravenous immunoglobulin has several uses, including management of patients with autoimmune thrombocytopenias and patients with acquired factor VIII deficiency. Similar to most protein-based biological medicines, all the above products can elicit some level of antibody response, with clinical consequences that vary from mild anaphylaxis to loss of product efficacy. An ongoing potential safety concern with any biological medicine derived from blood/plasma is transmission of blood-borne pathogens. This safety concern has lessened significantly in the past decade as a result of the institution of more effective pre- and post-donation screening that tests for potential pathogens, and institution of pathogen reduction strategies to which many plasma-derived biological medicines are now routinely subjected. This article considers the manufacture, standardization, clinical efficacy and adverse event profiles of the plasma-derived biological medicines currently used to promote haemostasis in patients with inherited or acquired functional defects in haemostasis. It also considers approaches employed to minimize infectivity of biological medicines derived from human and animal plasmas and to manage patients who develop antibodies (inhibitors) to clotting factor concentrate infusions.


Assuntos
Produtos Biológicos/uso terapêutico , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Fatores de Coagulação Sanguínea/uso terapêutico , Hemostasia/efeitos dos fármacos , Hemostáticos/uso terapêutico , Administração Tópica , Produtos Biológicos/administração & dosagem , Produtos Biológicos/efeitos adversos , Produtos Biológicos/isolamento & purificação , Transtornos da Coagulação Sanguínea/sangue , Fatores de Coagulação Sanguínea/administração & dosagem , Fatores de Coagulação Sanguínea/efeitos adversos , Fatores de Coagulação Sanguínea/isolamento & purificação , Fator VIII/uso terapêutico , Fator XIII/uso terapêutico , Fibrinogênio/uso terapêutico , Hemostasia Cirúrgica/métodos , Hemostáticos/administração & dosagem , Hemostáticos/efeitos adversos , Hemostáticos/isolamento & purificação , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Fator de von Willebrand/uso terapêutico
20.
Biologicals ; 36(4): 227-33, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18329287

RESUMO

This study evaluated the feasibility of substituting expanded bed adsorption (EBA) chromatography for an existing chromatographic purification process for the isolation of prothrombin complex concentrate (PCC) from Cohn Supernatant I. The EBA chromatography (Streamline) resins were compared to the current DEAE-cellulose resin for the extraction of PCC from Cohn SNI. EBA chromatography resins efficiently bound PCC from Cohn SNI at a significantly higher flow rate of up to 300 cm/h compared to 30 cm/h for the current DEAE-cellulose process. Composition and yield of the recovered PCC reflected the elution conditions used. The results indicate that EBA chromatography could be used to efficiently produce PCC comparable to existing products.


Assuntos
Fatores de Coagulação Sanguínea/isolamento & purificação , Proteínas Sanguíneas/química , Cromatografia/métodos , Resinas de Troca Aniônica/farmacologia , Técnicas de Laboratório Clínico , Indústria Farmacêutica/métodos , Humanos , Protrombina/isolamento & purificação , Soroalbumina Bovina/química
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