Apoptosis is an essential part of the normal cellular phenotype repertoire. In the absence of appropriate survival factors, apoptosis is activated through specific signalling cassettes. Epithelia form distinctive three‐dimensional cohesive structures that depend on adhesive interactions in order for these tissues to carry out their specialised roles, such as secretion and reproduction. The cellular programme that triggers apoptosis in epithelial cells has not yet been shown to differ from that in other cell types, yet the unique characteristics of epithelia endow (...) them with specific determinants for survival. In particular, cell‐matrix and cell‐cell interactions are required to prevent entry of epithelial cells into apoptosis, and soluble factors that have profound effects on epithelia, such as steroid hormones or hepatocyte growth factor, also influence their survival. The regenerative capacity of certain epithelia is controlled by intrinsic expression of survival genes within stem cell populations, and may regulate the susceptibility of different epithelial tissues to undergo carcinogenesis. (shrink)

Receptor tyrosine kinases and integrins are activated by growth factors and extracellular matrix, respectively. Their activation leads to signal transduction cascades that control many aspects of cell phenotype, including progression through the G1 phase of the cell cycle. However, the signalling cassettes driven by growth factors and matrix do not work independently of each other. Integrin triggering is essential to facilitate kinase‐ and GTPase‐mediated signals and thereby drive efficient transfer of information through the growth factor–cyclin axis. A recent study indicates (...) that an additional type of player has a key role in adhesion‐regulated control of cell cycle, namely ubiquitin ligase.(1) BioEssays 24:17–21, 2002. © 2002 John Wiley & Sons, Inc. (shrink)

Viola and Ben, two pediatric oncology patients, need to undergo chemotherapy that might decrease their fertility. Both of them want to participate in the decisions related to their cancer treatment and fertility preservation. Should they be involved, and if so when and how?In many jurisdictions, children are not entitled to provide legally valid consent for medical decisions.1 As a result, others, usually parents, take on the role of surrogate decision-makers who act in their best interest. Still, it is important to (...) keep in mind that the age limit for competence set by legislation does not necessarily coincide with children’s clinical decision-making capacity: some children may be able to make certain health-care... (shrink)

Streets have always drawn the attention of photographers. As both defining features of urban landscapes and places for all varieties of chance encounter, they offer a nearly endless combination of static and moving elements that are the stuff of stunning photography--as the photographers in Road Atlas show brilliantly. From classic New York City street scenes by Helen Levitt to the works of the more contemporary street photographers, including, among others, Philip-Lorca diCorcia, Beat Streuli, and Pieter Hugo, Road Atlas presents (...) a survey of the very best of street photography. Captured here is the everyday bustle of streets, sidewalks, and alleyways from Tokyo to São Paulo and beyond, offering tantalizing glimpses of buildings and their inhabitants, people immersed in their daily activities--shedding light, in the process, on poverty and prosperity, stagnation and vanishing urban spaces, and sometimes even of radical change. Through the practiced eyes of the twenty-eight artists showcased here, streets are threads linking cities and bringing people together yet also tokens of the distances that separate them and consign them to solitude. With more than 100 photographs from the renowned DZ Bank art collection in Frankfurt, Road Atlas captures both the oft-overlooked moments of everyday life and the distinctive character of cities worldwide. It accompanies an exhibition that will also be shown at the Opelvillen Rüsselsheim and the Kunstmuseum Dieselkraftwerk Cottbus. (shrink)