Low tumour cell proliferation at the invasive margin is associated with a poor prognosis in Dukes' stage B colorectal cancers

The conflicting results about the prognostic impact of tumour cell proliferation in colorectal cancer might be explained by the heterogeneity observed within these tumours. We have investigated whether a systematic spatial heterogeneity exists between different compartments, and whether the presence of such a systematic heterogeneity has any impact on survival. Fifty-six Dukes' stage B colorectal cancers were carefully morphometrically quantified with respect to the immunohistochemical expression of the proliferative marker Ki-67 at both the luminal border and the invasive margin. The proliferative activity was significantly higher at the luminal border compared with the invasive margin (P < 0.001), although the two compartments were also significantly correlated with each other. Tumours with low proliferation at the invasive margin had a significantly poorer prognosis both in univariate (P = 0.014) and in multivariate survival analyses (P = 0.042). We conclude that Dukes' B colorectal cancers exhibit a systematic spatial heterogeneity with respect to proliferation, and tumours with low proliferation at the invasive margin had a poor prognosis. The present data independently confirm recent results from the authors, and provide new insights into the understanding of tumour cell proliferation in colorectal cancer. © 1999 Cancer Research Campaig

Climate change and freshwater zooplankton: what does it boil down to?

Recently, major advances in the climate–zooplankton interface have been made some of which appeared to receive much attention in a broader audience of ecologists as well. In contrast to the marine realm, however, we still lack a more holistic summary of recent knowledge in freshwater. We discuss climate change-related variation in physical and biological attributes of lakes and running waters, high-order ecological functions, and subsequent alteration in zooplankton abundance, phenology, distribution, body size, community structure, life history parameters, and behavior by focusing on community level responses. The adequacy of large-scale climatic indices in ecology has received considerable support and provided a framework for the interpretation of community and species level responses in freshwater zooplankton. Modeling perspectives deserve particular consideration, since this promising stream of ecology is of particular applicability in climate change research owing to the inherently predictive nature of this field. In the future, ecologists should expand their research on species beyond daphnids, should address questions as to how different intrinsic and extrinsic drivers interact, should move beyond correlative approaches toward more mechanistic explanations, and last but not least, should facilitate transfer of biological data both across space and time

Exploring the Manifestations of Anxiety in Children with Autism Spectrum Disorders

This study explores the manifestation and measurement of anxiety symptoms in 415 children with ASDs on a 20-item, parent-rated, DSM-IV referenced anxiety scale. In both high and low-functioning children (IQ above vs below 70), commonly endorsed items assessed restlessness, tension and sleep difficulties. Items requiring verbal expression of worry by the child were rarely endorsed. Higher anxiety was associated with functional language, IQ above 70 and higher scores on several other behavioral measures. Four underlying factors emerged: Generalized Anxiety, Separation Anxiety, Social Anxiety and Over-arousal. Our findings extend our understanding of anxiety across IQ in ASD and provide guidance for improving anxiety outcome measurement