Using the layer-by-layer technique, ELISA polystyrene plates were coated with multilayer assemblies of albumin with various heparins or with multilayer assemblies of albumin. The coatings containing heparin were tested for their ability to potentiate thrombin inhibition by antithrombin and its dependence on the layer arrangement. The order of activities of surface bound heparins matched their order in solution; however their activity was reduced to less than 10% due to binding. The increasing number of layers increased the activity of the coatings suggesting that heparin inside the assemblies is available for the interaction. The albumin-heparin assemblies overcoated with albumin layers preserved about half of heparin activity. Platelets adhered in similar amounts to albumin-heparin and albumin coatings; however, in both cases platelets adhered more to single layer than to multilayer coatings. The adhesion of platelets to single layer coatings was also affected by the crosslinking of the coatings; more platelets adhered to less crosslinked single layer coatings while multilayer coatings remained essentially unaffected by crosslinking. If the coatings were dried and reswollen, a substantial number of platelets adhered to the reconditioned single layer coatings but the two layer coatings were affected much less and the adhesion of platelets to the coatings with three layers was close to normal. A minimum of three albumin-heparin or albumin layers is apparently required to shield the underlying surface and to achieve proper functioning of the coatings.
- MeSH
- adhezivita trombocytů účinky léků MeSH
- biokompatibilní potahované materiály chemická syntéza MeSH
- financování organizované MeSH
- heparin metabolismus MeSH
- lidé MeSH
- počet trombocytů MeSH
- prasata MeSH
- reagencia zkříženě vázaná farmakologie MeSH
- sérový albumin hovězí metabolismus MeSH
- skot MeSH
- spektroskopie infračervená s Fourierovou transformací MeSH
- testování materiálů metody MeSH
- trombin antagonisté a inhibitory MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- skot MeSH
- zvířata MeSH
INTRODUCTION: Various dysfibrinogenemias have been described worldwide. This paper describes two new cases of dysfibrinogenemia identified in the Czech Republic. MATERIALS AND METHODS: The proposita of fibrinogen Novy Jicin, a 12-year-old girl, presented with hemorrhagic complications, low Clauss fibrinogen level (0.3 g/l) and prolonged both thrombin (70.8 s) and reptilase (>180 s) time. Her mother and sister both presented with normal coagulation tests, normal fibrinogen level and reported no history of bleeding. The carriers of the fibrinogen Praha II were a 31-year-old man and his 11-year-old daughter. They both presented with low fibrinogen Clauss level (0.88 g/l) and prolonged thrombin and reptilase time. To identify the genetic mutation responsible for these dysfibrinogens, genomic DNA extracted from the blood was analyzed. The presence of the mutant chains in the circulation was determined by MALDI-TOF mass spectroscopy. Scanning electron micrographs of the patients' fibrin clots were obtained. RESULTS: The kinetics of fibrinopeptide release and fibrin polymerization were impaired for both fibrinogen Novy Jicin and Praha II. DNA sequencing showed heterogeneous fibrinogen Aalpha R16C mutation in the fibrinogen Novy Jicin case and heterogeneous fibrinogen Aalpha R16H in the fibrinogen Praha II case. The mutant chains were found to be expressed to the circulation by MALDI-TOF mass spectroscopy. Scanning electron micrographs of the patient's fibrin clot were found to be abnormal. CONCLUSIONS: The case of dysfibrinogenemia Aalpha R16C-fibrinogen Novy Jicin and the case of dysfibrinogenemia Aalpha R16H were found by routine coagulation testing and were genetically identified.
- MeSH
- afibrinogenemie genetika MeSH
- dítě MeSH
- dospělí MeSH
- fibrin metabolismus MeSH
- fibrinogeny abnormální genetika MeSH
- kinetika MeSH
- krvácení MeSH
- lidé MeSH
- missense mutace MeSH
- mutační analýza DNA MeSH
- vyšetření krevní srážlivosti MeSH
- zdraví rodiny MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Geografické názvy
- Česká republika MeSH
OBJECTIVES: A 25-yr-old man from Prague had abnormal bleeding after several surgical operations with low fibrinogen level and hypofibrinogenemia was suspected. PATIENTS AND METHODS: The patient, 25 yr-old male had a low fibrinogen concentration as determined by the thrombin time and immunoturbidimetrical method. His 48-yr-old mother presented with normal coagulation tests, normal fibrinogen level and reported no history of bleeding. To identify the genetic mutation responsible for this hypofibrinogen, genomic DNA extracted from the blood was analyzed. Fibrin polymerization measurement, kinetics of fibrinopeptide release, fibrinogen clottability measurement, mass spectroscopy, and scanning electron microscopy were performed. RESULTS: DNA sequencing showed heterogeneous fibrinogen gammaG351S mutation in the propositus. The mutant chain was found not to be expressed to the circulation by matrix-assisted laser desorption/ionization time of flight mass spectrometry. Scanning electron micrographs of the patient's fibrin clot as well as kinetics of fibrinopeptide release and fibrin polymerization were found to be normal. CONCLUSION: A case of hypofibrinogenemia gammaG351S was found by routine coagulation testing and was genetically identified.
- MeSH
- dospělí MeSH
- fibrinogen genetika metabolismus MeSH
- financování organizované MeSH
- glycin genetika MeSH
- krev MeSH
- lidé středního věku MeSH
- lidé MeSH
- mikroskopie elektronová rastrovací MeSH
- molekulární sekvence - údaje MeSH
- sekvence aminokyselin MeSH
- serin genetika MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
- Publikační typ
- abstrakt z konference MeSH
- Publikační typ
- abstrakt z konference MeSH
The biocompatibility of materials is frequently assessed by blood platelet adhesion, since platelet adhesion plays a considerable role in blood interaction with artificial surfaces. Blood platelets adhesion is an essential event in haemostatic and thrombotic processes. The aim of this study was to simultaneously compare simple biochemical assays widely used for evaluation of platelet static adhesion based on the determination of enzymatic activity of either lactate dehydrogenase (LDH) or acid phosphatase (ACP) in lysates of adhered platelets. Adhesion of platelets from platelet-rich plasma and washed platelets activated by either ADP or thrombin on surfaces covered with fibrinogen and well defined fibrin was studied. The results demonstrated that the amounts of adhered platelets estimated by the LDH method were significantly lower as compared with the amount obtained by ACP method. LDH but not ACP release from platelets during adhesion was shown to take place. It suggests that the LDH method should be used rather as an assay of platelet integrity. The ACP method is much more suitable for quantitative determination of platelet adhesion especially in the development and evaluation of haemocompatibility of new biomaterials.
- MeSH
- adenosindifosfát farmakologie MeSH
- adhezivita trombocytů * MeSH
- biokompatibilní materiály MeSH
- fibrin metabolismus MeSH
- fibrinogen * metabolismus MeSH
- kyselá fosfatasa analýza MeSH
- L-laktátdehydrogenasa analýza MeSH
- lidé MeSH
- testování materiálů * metody normy MeSH
- trombin farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- hodnotící studie MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- Publikační typ
- abstrakt z konference MeSH
