Beware of mereologists bearing gifts: prolegomena to a medical metaphysics.

This essay considers implications of formal mereologies and ontologies for medical metaphysics. Edward Fried's extensional mereological account of the human body is taken as representative of a prominent strand in analytic metaphysics that has close affinities with medical positivism. I show why such accounts fail. First, I consider how Fried attempts to make sense of the medical case of Barney Clark, the first recipient of an artificial heart, and show that his analytic metaphysical categories do not have the right kind of fit with the case. A proper medical metaphysic should involve a richer two way dialogue with medicine, and it should not just "apply" formal accounts worked out in other settings. Second, I argue that any effort to account for real wholes with extensional mereological sums requires all sorts of ad hoc, supplementary mechanisms that do the real work, and the full repertoire of these mechanisms involves inconsistencies and semantic shifts. Finally, I consider an alternative strand of work on non-extensional whole/part relations that is closer to medicine and that can deepen reflection on some core problems in bioethics, for example, associated with the determination of death when an organism ceases to function as a whole. In addition to the utility such formal ontologies have for addressing traditional problems such as the determination of death, philosophers of medicine should appreciate the increasingly influential role such formal tools are playing in the development of data system ontologies. Assumptions integral to these ontologies have far reaching implications for the way future research and practice in medicine will be conducted, and much greater critical reflection is needed on the full range of issues associated with the development and use of such medical ontologies.

Prolegomena to any future mereology of the body.

Many bioethical arguments rely implicitly on the assumption that the concept of "human part" is one on which everyone must agree, because it is unambiguous. But various parties interpret this "unambiguous" term in incompatible ways, leading to contention. This article is an informal presentation of a topomereological system on whose preferred interpretation several distinct but related meanings of "human part" can be isolated: part of a human body, part of the completion of a human body, and part of a human being. A case is analyzed (the first total artificial heart (TAH) implantation), demonstrating in the process much of the apparatus of the system. By means of a casuistic methodology, the analysis is translated into recommendations for the ethical conduct of future TAH research. The more general conclusion, however, is that formal methods may provide useful tools for clarifying thought processes and organizing arguments in debates over bioethical issues.

Polyacrylamide hydrogel injection in the management of human immunodeficiency virus-related facial lipoatrophy: a 2-year clinical experience.

BACKGROUND: Facial lipoatrophy is defined as the reduction in buccal and orbital fat pads along with a more global loss of fat within the subcutaneous tissue. It is the most common and distressing sign of human immunodeficiency virus-associated lipodystrophy. Injectable polyacrylamide hydrogel (Aquamid) is a synthetic nonbiodegradable polymer consisting of a minor backbone of 2.5 percent cross-linked polyacrylamide and 97.5 percent nonpyrogenic water and is used for cosmetic facial contour correction. Favorable results with maximum aesthetic gains with the use of polyacrylamide hydrogel for reconstruction of facial lipoatrophy on the face in significantly immunocompromised individuals are being reported. These results are attributable to its use in limited volume injected at multiple sites and in multiple sittings. METHODS: Aquamid has been used for the correction of severe nasolabial folds and mid and lower facial volume loss in patients affected by human immunodeficiency virus-associated lipodystrophy. Fifty patients were enrolled and treated, with a mean follow-up of 13.1 months. Results were evaluated clinically, by standardized ultrasonography, and by psychological tests (visual analogue scale, Beck Depression Inventory, and Assessment of Body Change and Distress questionnaire) to quantify patient satisfaction. RESULTS: No significant side effects or issues such as swelling, infections, allergies, or nodule formation were noted over the follow-up period. CONCLUSION: Aquamid has provided a minimally invasive, effective, long-lasting facial contour correction that significantly improves the quality of life in human immunodeficiency virus-infected patients.