BACKGROUND: Pathogen reduction technology (PRT) is increasingly used in the preparation of platelets for therapeutic transfusion. As the Czech Republic considers PRT, we asked what effects PRT may have on the recovery and function of platelets after cryopreservation (CP), which we use in both military and civilian blood settings. STUDY DESIGN AND METHODS: 16 Group O apheresis platelets units were treated with PRT (Mirasol, Terumo BCT, USA) before freezing; 15 similarly collected units were frozen without PRT as controls. All units were processed with 5-6% DMSO, frozen at - 80 °C, stored > 14 days, and reconstituted in thawed AB plasma. After reconstitution, all units were assessed for: platelet count, mean platelet volume (MPV), platelet recovery, thromboelastography, thrombin generation time, endogenous thrombin potential (ETP), glucose, lactate, pH, pO2, pCO2, HCO3, CD41, CD42b, CD62, Annexin V, CCL5, CD62P, and aggregates > 2 mm and selected units for Kunicki score. RESULTS: PRT treated platelet units had lower platelet number (247 vs 278 ×109/U), reduced thromboelastographic MA (38 vs 62 mm) and demonstrated aggregates compared to untreated platelets. Plasma coagulation functions were largely unchanged. CONCLUSIONS: Samples from PRT units showed reduced platelet number, reduced function greater than the reduced number would cause, and aggregates. While the platelet numbers are sufficient to meet the European standard, marked platelets activation with weak clot strength suggest reduced effectiveness.
- MeSH
- konzervace krve MeSH
- kryoprezervace MeSH
- kyselina mléčná MeSH
- lidé MeSH
- riboflavin farmakologie MeSH
- separace krevních složek * MeSH
- thrombin MeSH
- trombocyty fyziologie MeSH
- ultrafialové záření * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Antiphospholipid syndrome (APS) is a hypercoagulable state accompanied by the presence of heterogeneous antiphospholipid antibodies (aPL), which nonspecifically affect hemostasis by the presence of lupus anticoagulans (LA), anticardiolipin antibodies (aCL), antibodies against β2-glycoprotein-I (anti-β2GPI), but also non-criteria antibodies such as antibodies against β2-glycoprotein-I domain I (anti-DI), anti-phosphatidylserine/prothrombin (anti-PS/PT), anti-annexin V, and many others. The main target of the antibodies is the activated protein C (APC) system, the elimination of which can manifest itself as a thrombotic complication. The aim of this study was to determine the thrombogenicity of antibodies using a modified protein C-activated thrombin generation assay (TGA) on a group of 175 samples suspected of APS. TGA was measured with/without APC and the ratio of both measurements was evaluated (as for APC resistance), where a cut-off was calculated ≤4.5 (90th percentile) using 21 patients with heterozygous factor V Leiden mutation (FV Leiden heterozygous). Our study demonstrates the well-known fact that multiple positivity of different aPLs is a more severe risk for thrombosis than single positivity. Of the single antibody positivity, LA antibodies are the most serious (p value < 0.01), followed by aCL and their subgroup anti-DI (p value < 0.05). Non-criteria antibodies anti-annexin V and anti-PT/PS has a similar frequency occurrence of thrombogenicity as LA antibodies but without statistical significance or anti-β2GPI1 positivity. The modified TGA test can help us identify patients in all groups who are also at risk for recurrent thrombotic and pregnancy complications; thus, long-term prophylactic treatment is appropriate. For this reason, it is proving increasingly beneficial to include the determination antibodies in combination with modified TGA test.
- MeSH
- antifosfolipidové protilátky MeSH
- antifosfolipidový syndrom * komplikace MeSH
- antikardiolipinové protilátky MeSH
- beta-2-glykoprotein I MeSH
- fosfatidylseriny MeSH
- lidé MeSH
- protein C MeSH
- protrombin MeSH
- těhotenství MeSH
- thrombin MeSH
- trombóza * etiologie MeSH
- Check Tag
- lidé MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- MeSH
- antikoagulancia * farmakologie terapeutické užití MeSH
- dabigatran farmakologie terapeutické užití MeSH
- heparin farmakologie terapeutické užití MeSH
- inhibitory faktoru Xa farmakologie terapeutické užití MeSH
- lidé MeSH
- předoperační péče MeSH
- premedikace MeSH
- primární zdravotní péče MeSH
- thrombin antagonisté a inhibitory farmakologie terapeutické užití MeSH
- warfarin farmakologie terapeutické užití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
BACKGROUND: Islet transplantation represents an established therapeutic option for people with type 1 diabetes who have hypoglycemia unawareness syndrome and frequent problematic hypoglycemic episodes when other methods comprising diabetes education and use of technological support fail. Because the current standard method of islet infusion into the liver has some limitations, novel approaches are under investigation. METHODS: We report our first results with 2 cases of islet transplantation into an omental pouch using a biocompatible plasma-fibrin gel. The recipients received 12,350 and 5,350 islet equivalents per kilogram that were mixed with autologous plasma, seeded during a laparoscopic procedure on the omentum, overlaid with human thrombin solution, and fixed by flapping the omentum over. RESULTS: During a 9-month follow-up, neither patient experienced any moderate or severe hypoglycemia. Their glucose control significantly improved, insulin dose decreased by approximately 50%, and C-peptide at 1 year was 0.22 and 0.14 pmol/mL, respectively. The postoperative course was uneventful, but C-peptide production in the first patient progressively declined at 1 year and hypoglycemic episodes recurred. CONCLUSIONS: Though the results for these first 2 cases are not fully satisfactory, we have demonstrated the feasibility, safety, and ability of this novel method to restore insulin production. Further refinements to improve immediate islet survival seem necessary.
- MeSH
- biomedicínský výzkum * MeSH
- C-peptid MeSH
- diabetes mellitus 1. typu * farmakoterapie chirurgie MeSH
- hypoglykemie * farmakoterapie MeSH
- hypoglykemika terapeutické užití MeSH
- inzulin terapeutické užití MeSH
- krevní glukóza MeSH
- Langerhansovy ostrůvky * MeSH
- lidé MeSH
- omentum chirurgie MeSH
- thrombin terapeutické užití MeSH
- transplantace Langerhansových ostrůvků * škodlivé účinky metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Flavonoids are associated with positive cardiovascular effects. However, due to their low bioavailability, metabolites are likely responsible for these properties. Recently, one of these metabolites, 4-methylcatechol, was described to be a very potent antiplatelet compound. This study aimed to compare its activity with its 22 close derivatives both of natural or synthetic origin in order to elucidate a potential structure-antiplatelet activity relationship. Blood from human volunteers was induced to aggregate by arachidonic acid (AA), collagen or thrombin, and plasma coagulation was also studied. Potential toxicity was tested on human erythrocytes as well as on a cancer cell line. Our results indicated that 17 out of the 22 compounds were very active at a concentration of 40 μM and, importantly, seven of them had an IC50 on AA-triggered aggregation below 3 μM. The effects of the most active compounds were confirmed on collagen-triggered aggregation too. None of the tested compounds was toxic toward erythrocytes at 50 μM and four compounds partly inhibited proliferation of breast cancer cell line at 100 μM but not at 10 μM. Additionally, none of the compounds had a significant effect on blood coagulation or thrombin-triggered aggregation. This study hence reports four phenol derivatives (4-ethylcatechol, 4-fluorocatechol, 2-methoxy-4-ethylphenol and 3-methylcatechol) suitable for future in vivo testing.
- MeSH
- agregace trombocytů * MeSH
- fenol * MeSH
- fenoly farmakologie MeSH
- inhibitory agregace trombocytů farmakologie MeSH
- lidé MeSH
- thrombin farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
An ideal decellularized allogenic or xenogeneic cardiovascular graft should be capable of preventing thrombus formation after implantation. The antithrombogenicity of the graft is ensured by a confluent endothelial cell layer formed on its surface. Later repopulation and remodeling of the scaffold by the patient's cells should result in the formation of living autologous tissue. In the work presented here, decellularized porcine pericardium scaffolds were modified by growing a fibrin mesh on the surface and inside the scaffolds, and by attaching heparin and human vascular endothelial growth factor (VEGF) to this mesh. Then the scaffolds were seeded with human adipose tissue-derived stem cells (ASCs). While the ASCs grew only on the surface of the decellularized pericardium, the fibrin-modified scaffolds were entirely repopulated in 28 d, and the scaffolds modified with fibrin, heparin and VEGF were already repopulated within 6 d. Label free mass spectrometry revealed fibronectin, collagens, and other extracellular matrix proteins produced by ASCs during recellularization. Thin layers of human umbilical endothelial cells were formed within 4 d after the cells were seeded on the surfaces of the scaffold, which had previously been seeded with ASCs. The results indicate that an artificial tissue prepared by in vitro recellularization and remodeling of decellularized non-autologous pericardium with autologous ASCs seems to be a promising candidate for cardiovascular grafts capable of accelerating in situ endothelialization. ASCs resemble the valve interstitial cells present in heart valves. An advantage of this approach is that ASCs can easily be collected from the patient by liposuction.
- MeSH
- bioprotézy MeSH
- decelularizovaná extracelulární matrix chemie MeSH
- endoteliální buňky pupečníkové žíly (lidské) MeSH
- endoteliální buňky cytologie MeSH
- extracelulární matrix metabolismus MeSH
- fibrinogen chemie MeSH
- fibronektiny chemie MeSH
- fluorescenční mikroskopie MeSH
- kmenové buňky MeSH
- kolagen chemie MeSH
- lidé MeSH
- lipektomie MeSH
- perikard metabolismus patologie MeSH
- prasata MeSH
- proliferace buněk MeSH
- srdeční chlopně * MeSH
- techniky in vitro MeSH
- thrombin chemie MeSH
- tkáňové inženýrství metody MeSH
- tkáňové podpůrné struktury * chemie MeSH
- tuková tkáň cytologie MeSH
- vaskulární endoteliální růstový faktor A metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Nová perorální antikoagulancia, která se také pro svůj přímý inhibiční účinek trombinu nebo faktoru Xa označují jako přímá perorální antikoagulancia, reprezentují progresivně se uplatňující skupinu antitrombotických léčiv v klinické praxi. Z pohledu trávicího traktu je nutné jednak respektovat farmakokinetické procesy vstřebávání a metabolické přeměny účinných látek na cestě k dosažení vlastního farmakologického účinku, jednak nezapomínat na rizika terapie v podobě krvácení, dyspeptických obtíží a hepatopatie. Speciálni případ posouzení aktuálního rizika krvácení vs. trombotické komplikace představuje oblast intervenční endoskopické gastroenterologie.
New oral anticoagulants, also known as direct oral anticoagulants due to their direct inhibitory effects towards thrombin or factorXa, represent a progressive group of antithrombotic drugs in clinical therapy. Regarding alimentary tract, it is necessary to respectthe pharmacokinetic processes of absorption and metabolic conversion of effective compounds to achieve the particular pharmacologicaleffect. In addition, particular risks of bleeding, dyspeptic discomfort and hepatopathy are to be concerned too. Theevaluation of the actual risk of bleeding versus thrombotic complication introduces the special case of intervention endoscopicgastroenterology.
- Klíčová slova
- přímá perorální antikoagulancia, apixaban, edoxaban,
- MeSH
- antikoagulancia * aplikace a dávkování škodlivé účinky MeSH
- aplikace orální MeSH
- dabigatran aplikace a dávkování farmakokinetika škodlivé účinky MeSH
- endoskopie trávicího systému MeSH
- inhibitory faktoru Xa terapeutické užití MeSH
- lidé MeSH
- rivaroxaban aplikace a dávkování farmakokinetika MeSH
- thrombin antagonisté a inhibitory MeSH
- Check Tag
- lidé MeSH
Hyperkoagulační stavy patří mezi nejčastější příčiny morbidity i mortality v průmyslově rozvinutých zemích. Hemostáza hraje přitom důležitou roli nejen v zástavě krvácení, ale podílí se i na imunitní obraně organizmu, regulaci hojení ran a významně se účastní i procesů růstu, progrese a metastázování zhoubných nádorů. Není proto divu, že pozornost řady výzkumných týmů je upřena na řešení mnoha důležitých otázek v této rozsáhlé oblasti, včetně problematiky vývoje nových antitrombotických léků. Procesy hemostázy jsou přitom prozkoumávány na mnoha úrovních, což umožňuje vyvíjet a zkoušet antitrombotika nové generace, která jsou postupně testována v preklinických i klinických studiích. Do popředí zájmu kliniků se v současné době dostaly látky typu pentasacharidů, přímé inhibitory faktoru Xa a přímé inhibitory trombinu. Lze očekávat, že tato nová antitrombotika v budoucnosti
Hypercoagulable states are among the most frequent causes of morbidity and mortality in the developed countries. Hemostasisplays an important role not only in the stopping of bleeding, but is also involved in immunity, wound healing, and the processesof growth, progression, and metastasizing of malignant tumors. This is the reason why many research teams pay great attention tothe issue of hemostasis, including the development of new antithrombotic drugs. Hemostasis is being explored in detail on manylevels, this creating a basis for the development and testing of new drugs in both preclinical and clinical trials. At present, pentasacharides,direct inhibitors of factor Xa, and direct trombin inhibitors are the most promising drugs. These new antithromboticscan be expected to replace the classic drugs (heparins and vitamin K antagonists) in the prevention and treatment of thrombosisin both the venous and arterial circulations.
- MeSH
- antikoagulancia * aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- dabigatran aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- hemostáza fyziologie genetika účinky léků MeSH
- heparin aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- inhibitory agregace trombocytů * aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- inhibitory faktoru Xa aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- lidé MeSH
- metaanalýza jako téma MeSH
- oligosacharidy aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- polysacharidy aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- pyrazoly aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- pyridiny aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- pyridony aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- rivaroxaban aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- statistika jako téma MeSH
- thiazoly aplikace a dávkování škodlivé účinky terapeutické užití MeSH
- thrombin antagonisté a inhibitory aplikace a dávkování terapeutické užití MeSH
- trombofilie * farmakoterapie komplikace prevence a kontrola MeSH
- vitamin K antagonisté a inhibitory aplikace a dávkování terapeutické užití MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
Human aldo-keto reductase 1C3 (AKR1C3) stereospecifically reduces steroids and prostaglandins and is involved in the biotransformation of xenobiotics. Its role in various cancers makes it a potential therapeutic target for the development of inhibitors. Recombinant AKR1C3 with a thrombin-cleavable N-terminal His6 tag was expressed from a pET-28(+) vector for structural studies of enzyme-inhibitor complexes. A modified in situ proteolysis approach was applied to specifically remove the His tag by thrombin cleavage during crystallization screening trials. This improved the morphology and diffraction quality of the crystals and allowed the acquisition of high-resolution diffraction data and structure solution. This approach may be generally applicable to other proteins expressed using the pET-28(+) vector.
- MeSH
- difrakce rentgenového záření metody MeSH
- histidin * genetika MeSH
- krystalizace metody MeSH
- krystalografie rentgenová metody MeSH
- lidé MeSH
- protein AKR1C3 chemie genetika metabolismus MeSH
- proteolýza MeSH
- sekvence aminokyselin MeSH
- thrombin metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
