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In this mini-review, we discuss implantable cardiovascular devices (ICVDs)-associated biofilm infections that have caused huge healthcare challenges, and their treatment not only has caused serious threats to human health, but it also imposed an exorbitant cost on communities worldwide. Solutions toward better managing biofilm formation on ICVDs will be provided, both in vitroand in vivoor in clinical trials. Furthermore, we provide expert recommendations to move the field of ICVDs towards more sustainable and durable surfaces on implantable devices that can significantly reduce both the imposed cost on healthcare (by reducing the rate of hospitalization, re-surgery, etc.) and patients suffering from prolonged medical care. Finally, we discuss the promises and pitfalls along with the solutions in the use of ICVDs for cardiovascular disease therapeutics and diagnostics.

Summary: The experimental procedures were undertaken in order to characterize of surface‐modified metallic substrates. Results revealed that carbon layers coating the substrates made metallic surface generally more biocompatible and more resistant to biofilm formation. Titanium‐nitride or titanium carbo‐nitride layers on the titanium alloy (Ti6Al4V) allow for modulation of thrombogenity degree of the surface. Our investigations employed several methods: fluorescence and electron microscopy techniques, SPR‐biosensor technology, 2D‐electrophoresis and flow cytofluorymetry.

Heat shock proteins (hsp) are known to facilitate the generation of specific immune responses by chaperoning proteins and peptides involved in T cell activation. Hsp have been shown to be strikingly elevated in multiple sclerosis (MS) lesions. The unique chaperonin properties of hsp70 have allowed identification of immunogenic proteins bound to it by the ex vivo demonstration of hsp associations with proteins implicated in the immune response. We have investigated the association of hsp70 with myelin basic protein (MBP), myelin proteolipid protein (PLP) and myelin oligodendrocyte protein (MOG) in MS and control brain tissue. In co-immunoprecipitation experiments, in all samples of MS brains examined (n = 3), but not control brain tissue (n = 3), direct association of MBP with hsp70, but not with hsp90, was found. In some MS brain samples, association between PLP and hsp70 was also seen. In similar co-immunoprecipitation experiments on brain tissue obtained from mice with experimental autoimmune encephalomyelitis (n = 5) induced by immunization with PLP peptide, specific association of hsp70 with PLP and MBP was found. Using surface plasmon resonance we demonstrated specific binding of hsp70 with MBP in vitro. Analysis of the amounts of MBP bound to hsp70 yielded a molecular ratio of MBP binding to hsp70 at 6.5:1. MBP complexed with hsp70 was taken up at significantly higher rates by antigen-presenting cells than MBP alone and enhanced MBP-specific immune responses. These results indicate that hsp70 specifically associates with MBP in MS brain tissue. This association might be relevant to the enhanced immune recognition of MBP in MS.

α1-Acid glycoprotein, one of the major acute phase proteins, was found to interact with plasminogen activator inhibitor type 1 (PAI-1) and to stabilize its inhibitory activity toward plasminogen activators. This conclusion is based on the following observations: (a) α1-acid glycoprotein was identified to bind PAI-1 by a yeast two-hybrid system. Three of 10 positive clones identified by this method to interact with PAI-1 contained almost the entire sequence of α1-acid glycoprotein; (b) this protein formed complexes with PAI-1 that could be immunoprecipitated from both the incubation mixtures and blood plasma by specific antibodies to either PAI-1 or α1-acid glycoprotein. Such complexes could be also detected by a solid phase binding assay; and (c) the real-time bimolecular interactions monitored by surface plasmon resonance indicated that the complex of α1-acid glycoprotein with PAI-1 is less stable than that formed by vitronectin with PAI-1, but in both cases, the apparentKDvalues were in the range of strong interactions (4.51 + 1.33 and 0.58 + 0.07 nm, respectively). The on rate for binding of PAI-1 to α1-glycoprotein or vitronectin differed by 2-fold, indicating much faster complex formation by vitronectin than by α1-acid glycoprotein. On the other hand, dissociation of PAI-1 bound to vitronectin was much slower than that from the α1-acid glycoprotein, as indicated by 4-fold lower koffvalues. Furthermore, the PAI-1 activity toward urokinase-type plasminogen activator and tissue-type plasminogen activator was significantly prolonged in the presence of α1-acid glycoprotein. These observations suggest that the complex of PAI-1 with α1-acid glycoprotein can play a role as an alternative reservoir of the physiologically active form of the inhibitor, particularly during inflammation or other acute phase reactions.

Results of platelet aggregation measured with a dual channel aggregometer and with a microplate reader are compared. Platelets in plasma were activated by ADP and by collagen, and thrombin was used for the aggregation study of gel filtered platelets. The results obtained with both instruments were quantitatively and qualitatively similar. A microplate reader allowed a simultaneous measurement of a high number of samples with a high degree of reproducibility. The same instrument can be useful in other coagulology studies. Results of citrated plasma clotting by thrombin or by recalcination together with results of platelet counting, both obtained with a microplate reader, are presented in this report as well. © 1997 Elsevier Science Ltd

The transport of L-leucine into human blood platelets was characterized as a function of time and amino acid concentration in the medium. Inhibition analyses showed that L-leucine uptake can be only partially inhibited by other amino acids including those which are believed to be transported by the same Lsystem. When Cu2+, Zn2+, Mg2+, Co2+, Fe2+, Ba2+, or Cd2+ were introduced into the transport medium to the final concentrations of 2.5 and 5.0 mM, they inhibited significantly the L-leucine uptake into platelets. In contrast, the initial rate of L-leucine uptake was nhanced by Cu+ ions. Ceruloplasmin, a copper transporting protein, caused almost a complete inhibition of L-leucine uptake.

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