The heme‐containing cytochromes P‐450 are a ubiquitous family of monooxygenase isozymes responsible for the oxidative metabolism of a wide variety of endogenous as well as exogenous compounds. Many of the compounds metabolized by this enzyme system are effectively detoxified and converted to derivatives more easily eliminated from the organism. However, some compounds can be activated to reactive species capable of eliciting a cascade of toxic lesions, including cancer. Since its discovery nearly 30 years ago, the cytochrome P‐450 enzyme system has (...) received a great deal of attention, particularly in the areas of their mechanisms of metabolism, range of substrate specificity, the purification and characterization of the multiple isozymes and, more recently, the regulation of expression of specific forms. This review will discuss current notions concerning the expression of at least one cytochrome P‐450 isozyme and future directions that should lead to a more complete understanding of cytochrome P‐450 gene expression in general, particularly as it impacts upon biochemical pharmacology. (shrink)

The relation of the conformal group to various earlier proposed relativistic quantum mechanical dynamical groups (and other related groups) is studied in the framework of projective geometry, by explicitly constructing the contractions of the six-dimensional coordinate transformations. Five-dimensional realizations are then derived. An attempt is made to improve our physical insight through geometry.

As the usual regulatory framework did not fit well during the last Ebola outbreak, innovative thinking still needed. In the absence of an outbreak, randomised controlled trials of clinical efficacy in humans cannot be done, while during an outbreak such trials will continue to face significant practical, philosophical, and ethical challenges. This article argues that researchers should also test the safety and effectiveness of novel vaccines in wild apes by employing a pluralistic approach to evidence. There are three reasons to (...) test vaccines in wild populations of apes: i) protect apes; ii) reduce Ebola transmission from wild animals to humans; and iii) accelerate vaccine development and licensing for humans. Data obtained from studies of vaccines among wild apes and chimpanzees may even be considered sufficient for licensing new vaccines for humans. This strategy will serve to benefit both wild apes and humans. (shrink)

We look at a hierarchical arrangement of ideals in an MV -algebra. The principal classes of ideals studied are the maximals, the primes, the local and perfect ideals and the semi-locals. Beyond these special classes of ideals are the general ideals. Herein we study some relationships among these classes and, more specifically, the products of ideals of these classes. Among the results obtained are the square of a prime ideal is a local ideal, the finite product of prime ideals is (...) a semilocal ideal. We also show that the set of local ideals shares many of the properties of the class of prime ideals, as the Lying Over Theorem and the Going Up Theorem. (shrink)

In this paper I argue that warrant for Lewis’ principle of recombination presupposes warrant for a combinatorial analysis of intrinsicality, which in turn presupposes warrant for the principle of recombination. This, I claim, leads to a vicious circularity: warrant for neither doctrine can get off the ground.

The terms “competency” and “decision making capacity” are often used interchangeably in the medical setting. Although competency is a legal determination made by judges, “competency” assessments are frequently requested of psychiatrists who are called to consult on hospitalised patients who refuse medical treatment. In these situations, the bioethicist is called to consult frequently as well, sometimes as a second opinion or “tie breaker”. The psychiatric determination of competence, while a clinical phenomenon, is based primarily in legalism and can be quite (...) different from the bioethics approach. This discrepancy highlights the difficulties that arise when a patient is found to be “competent” by psychiatry but lacking in DMC by bioethics. Using a case, this dilemma is explored and guidance for reconciling the opinions of two distinct clinical specialties is offered. (shrink)

Spanish influence in the New World was particularly acute in the areas of medicine and medical education. From the time of Columbus forward prominent medical experts journeyed to Latin America establishing medical schools and research centers. This essay chronicles the history of Latin America with a strong focus on the physicians and scientists who brought modern scientific medicine, as it wag then known in Western Europe, to the Americas.