Blood/materials interactions

Before summarizing relevant experimental findings, it is appropriate to review briefly the theoretical and practical limitations to our understanding of blood-material interactions. 

Handbook of Biomaterial Properties. Edited by J. Black and G. Hastings. Published in 1998 by Chapman Hall, London. ISBN 0 412 60330 6. 

Size and shape Surface composition Texture or roughness Mechanical properties Blood Flow Phenomena Shear forces 

Convection and diffusion of reactants, products, cofactors and inhibitors Disturbed flow and turbulence Blood Chemistry-related Effects Coagulation status Antithrombotic and other therapies Contrast media Other Variables 

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Surface physics and chemistry play a major role as far as blood-material interactions are concerned. However, the observed processes depend as much on the local flow patterns of the blood near the material surface as on these surface characteristics. 

All of this tends to indicate that we may be making a mistake when we look only at the clotting problem resulting from the blood/material interaction. This may merely be a very visible effect of the denaturation of one particular protein in the blood. The solution of the clotting problem may very well only allow us to recognize the fact that other factors are involved and that we have failed to look at the total picture. 

Guidelines for Blood-Material Interactions" Mason, R.G., Ed. Publication No. (NIH) 80-2185 U.S. Department of Health and Human Services, 1980. 

This volume contains manuscripts based on 28 of the 32 contributions presented at the Chicago AIChE Biomaterials Symposium. These manuscripts are organized into three major sections Blood-Materials Interactions, Protein Adsorption on Biomaterials, and New Biomaterials Systems and Applications. Introductory chapters are placed at the beginning of each section of the book to provide nonspecialists with background material and a perspective into these evolving research areas. 

The blood-materials interactions section contains a review article dealing with surface characterization. Consideration of the surface structure of biomaterials is critical to every study in this volume. This section contains 16 chapters dealing with the choice of in vivo and in vitro methods of biomaterials evaluation, biomaterials selection and modification, and cellular interactions with candidate surfaces. Individual papers dealing with the use of dogs, baboons, and goats for in vivo blood-materials evaluation can be found together with in vitro methods. There are also several contributions on polyurethanes, which are prime candidates for use in blood contacting devices. 

Guidelines for Blood-Material Interactions, U.S. Department of Health and... 

Report of the National Heart, Lung, and Blood Institute Working Group Guidelines for Blood-Material Interactions, NIH Publ. No. 80-2185, Bethesda, MD., 1980. 

The laser scattering technique is newly developed, and probably will be extremely valuable in quantitating the differences in embolic events during blood-material interactions, and thus potentially useful in elucidating the mechanisms responsible for these differences. 

Salzman, E. W. Blood-Material Interaction Lecture, Devices and Technology... 

While studies of platelet and thrombus accumulation on surfaces have provided important information concerning blood-material interactions, that accumulation is not a direct index of the rate of microemboli generation [e.g., kidney embolism induced by implanted aortic rings often was most severe from rings that remained clean (26, 27)]. Thus, analytical tests that directly quantify microemboli are needed. 

Guidelines for Blood- Material Interactions. U.S. Dept. Health and Human Services, Devices and Technology Branch. NHLBI, NIH Pub. No. 80-2185, Sept. 1980. 

Protein Adsorption at the Solid-Solution Interface in Relation to Blood-Material Interactions... 

Clearly studies of single proteins and of mixtures in buffer solutions provide useful information as is evident from the above discussion. However, only studies using blood or plasma can give definitive answers regarding blood material interactions. Accordingly much of our research over the past several years has been devoted to studies of protein adsorption from plasma or blood. 

HE CURRENT STATE OF KNOWLEDGE of proteins at interfaces is reflected in this book. Developed from a symposium that was one of a continuing series entitled Surface Chemistry in Biology, Dentistry, and Medicine, the book is organized around the subtopics of behavior, mechanisms, methods of study, blood-material interactions, and applications of proteins at solid-liquid, air-water, and oil-water interfaces. 

In the present paper, we review the totality of these data and attempt a synthesis of our current knowledge of this system. Such a synthesis relates both to the fundamental aspects of the interaction and to its relationship to blood-material interactions, incorporating both our own work and that of others. In the context of the present Symposiun this paper will serve the additional purpose of Illustrating some of the principles of protein adsorption discussed in the paper of Andrade (this volume). 

During blood contact with any foreign material, several components in the blood are activated through a variety of enzymatic and cellular processes. In the setting of chronic hemodialysis with up to 15 h of weekly blood—material interactions, the immune system, in particular, appears to be in a constantly activated, inflammatory state. Some have su ested the high incidence of infection and septicemia in these patients is due, in part, to the activated immune system s inability to adequately respond to microbial pathogens. Therefore, the search for more biocompatible materials for hemodialysis and hemoperfusion is of great importance. 

In addition to blood-material interaction, fibrous encapsulation, and microbial infection, implantable prostheses are associated with a multitude of other interrelated biological phenomena including specific immunologic reactions, complement activation, systemic toxicity, hypersensitivity, and implant-associated tumor formation [9]. For more detailed discussion on these biological processes, the readers are referred to specialized textbooks [9,17] and reviews [12,30,40],... 

S.R. Hanson, E.I. Tucko", Blood coagulation and blood-materials interactions, in B.D. Ratner, AS. Hoffman, E.J. Schoen, J.E. Lemons (Eds.), Biomataial Sdence An Introduction to Materials in Medicine, third ed.. Academic Press, Elsevier, Waltham, MA, USA, 2013. 

In the following, a set of incubation systems and procedures, suitable for both fundamental and application-oriented studies of blood-material interactions, are described. 

In this model, the possible blood-material interactions are as follows the hydrated flexible PEO chain motion suppresses protein adsorption and platelet adhesion, where the PEO chain motion will be increased by the electric repulsion between sulfonate end groups each other. In addition, the sulfonated end groups of PEO chain expel proteins and platelets further by electric repulsion, and moreover the sulfonate groups miglit contribute to better blood compatibility by inhibiting blood coagulation factors. 

Blood-material interactions Provisional matrix formation Acute inflammation Chronic inflammation Granulation tissue Foreign body reaction Fibrosis/fibrous capsule development... 

Figure 3. Sequence of events during blood-material interactions.

While it is convenient to consider blood-material interactions separately from tissue-material interactions, it must be emphasized that blood-material interactions and the inflammatory response are intimately linked and, in fact, early responses to injury involve mainly blood and blood vessels. Therefore, both cellular and humoral elements, i.e., plasma proteins, etc., are considered as cells and components of vascularized connective tissue. 

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