Advance care directives for health care have been promoted as a way to improve end-of-life decision making. These documents allow a patient to state, in advance of incapacity, the types of medical treatments they would like to receive, to name a surrogate to make those decisions, or to do both. Although studies have shown that both physicians and patients generally have positive attitudes about the use of these documents, relatively few individuals have actually completed one.What underlies this discrepancy between attitudes (...) and behavior with regard to advance care directives? One obvious explanation is lack of access. Emanuel et al. estimated that approximately 90 percent of the population desire an advance care directive, and they pointed to access as the major barrier. Yet interventions that increase accessibility have typically failed to yield more than a 20 percent completion rate. Thus, it appears that access is not the sole determinant of advance care directive completion. (shrink)

A major shift has taken place since the 1960s concerning disclosure to patients that they have a diagnosis of cancer and that their disease is considered terminal. Full disclosure is now considered the patient's right in the United States. However, there remain many countries in which nondisclosure is still the norm. When patients from those countries are diagnosed with cancer in America, differences in attitudes and expectations can cause conflict and misunderstanding.

Like most bilaterian animals, the annelid Platynereis dumerilii generates the majority of its body axis in an anterior to posterior temporal progression with new segments added sequentially. This process relies on a posterior subterminal proliferative body region, known as the "segment addition zone" (SAZ). We explored some of the molecular and cellular aspects of posterior elongation in Platynereis, in particular to test the hypothesis that the SAZ contains a specific set of stem cells dedicated to posterior elongation.We cloned and characterized (...) the developmental expression patterns of orthologs of 17 genes known to be involved in the formation, behavior, or maintenance of stem cells in other metazoan models. These genes encode RNA-binding proteins(e.g., tudor, musashi, pumilio) or transcription factors(e.g., myc, id, runx) widely conserved in eumetazoans. Most of these genes are expressed both in the migrating primordial germ cells and in overlapping ring-like patterns in the SAZ, similar to some previously analyzed genes(piwi, vasa). The SAZ patterns are coincident with the expression of proliferation markers cyclin B and PCNA. EdU pulse and chase experiments suggest that new segments are produced through many rounds of divisions from small populations of teloblast-like posterior stem cells. The shared molecular signature between primordial germ cells and posterior stem cells in Platynereis thus corresponds to an ancestral "stemness" program. (shrink)