Cardiovascular medical applications

Butyl rubber - This material generally had the least endurance in fatigue tests, but it may be adequate for some cardiovascular applications. Advantages include less sensitivity to stress concentrators than Pellethane, a very low permeability to fluids, a moderate creep resistance and widespread availability at low cost. Disadvantages include a relatively low fatigue resistance compared to the elastomers specifically designed for these applications. The rubber tested was not designed for medical applications and had standard rubber additives and modifiers that were cytotoxic unless the material was extracted after manufacture. 

This aspect makes it clear why optical fibre sensors for medical applications have been characterised by a remarkable development after the introduction of optical fibres. The first invasive optical fibre oximeter which was described in 19641, can be considered one of the first optical fibre sensors. Since then, many sensors have been proposed which find application in different biomedical areas, ranging from cardiovascular and intensive care to angiology, gastroenterology and ophthalmology. Some of these are still at the prototype level, whereas others are already available on the market. 

Ephedrine is the main alkaloid produced in the roots of Ephedra sinica, preparations of which have found medical application in China for at least 5000 years. It was first purified from its natural source in 1887, and its chemical synthesis was achieved in 1927. It was initially used in cardiovascular medicine, but subsequently found wider application in the treatment of mild hayfever and asthma. It is also used as a nasal decongestant and cough suppressant. 

This last-mentioned successful series of control experiments, involving addition of cavitation nuclei to the cardiovascular system, brings to mind at least one feasible medical application for injected (synthetic) surfactant-stabilized microbubbles (cf. Chapters 9 and 10) as concerns evaluation of cardiovascular function. Various types of size-controlled, nontoxic, synthetic micro-... 

Since PTFE is highly inert and nontoxic, it finds use in medical applications for cardiovascular grafts, heart patches, ligaments for knees, and others.12... 

Docosahexaenoic add (22 6n-3 DHA) plays a role in the prevention of a number of human diseases, including cardiovascular disease (1-3), inflammation (4), and cancer (5,6). DHA has also been reported to have important functions in the brain (7) and retina (8), and to accelerate the growth of preterm infants (9,10). For these reasons, tuna oil containing DHA has been used as a functional food and as an ingredient for infant formula (11). In addition, the beneficial physiologic activities of DHA have stimulated interest in its medical application. 

Keywords Cardiovascular tissues Cosmetic tissues Medical applications Meniscus implant Nanocelluloses Nanocomposites Veterinary medicine... 

A fairly new field of interest is the use of microbraids in medical applications such as cardiovascular and neurotic stents, electroencephalography needles, endocardial electrodes and dmg delivery systems (Alt et al., 1995). 

Polyurethanes (PUs) have been used as a biomaterial for many years due to their excellent mechanical properties, biocompatibility, and adaptability (Coury et al., 1988). For example, traditional medical applications of PUs involve catheters, transdermal patches, transient cardiovascular devices, and intraaortic balloon pumps, among others (Chen et al., 2013). 

Biostability has been and continues to be a main research focus of PUs. Depending on the intended medical applications, the desired biostability of PUs varies. For example, PUs used as pacemaker lead covering should have superior long-term stability, whereas PUs used as a scaffold to build engineered tissue construct for replacement of diseased cardiovascular tissues should be biodegradable. The challenge to maintain long-term in vivo biostability... 

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