Intra-tumoural microvessel density in human solid tumours

Over the last decade assessment of angiogenesis has emerged as a potentially useful biological prognostic and predictive factor in human solid tumours. With the development of highly specific endothelial markers that can be assessed in histological archival specimens, several quantitative studies have been performed in various solid tumours. The majority of published studies have shown a positive correlation between intra-tumoural microvessel density, a measure of tumour angiogenesis, and prognosis in solid tumours. A minority of studies have not demonstrated an association and this may be attributed to significant differences in the methodologies employed for sample selection, immunostaining techniques, vessel counting and statistical analysis, although a number of biological differences may account for the discrepancy. In this review we evaluate the quantification of angiogenesis by immunohistochemistry, the relationship between tumour vascularity and metastasis, and the clinicopathological studies correlating intra-tumoral microvessel density with prognosis and response to anti-cancer therapy. In view of the extensive nature of this retrospective body of data, comparative studies are needed to identify the optimum technique and endothelial antigens (activated or pan-endothelial antigens) but subsequently prospective studies that allocate treatment on the basis of microvessel density are required

Regional Climate Shifts Caused by Gradual Global Cooling in the Pliocene Epoch

The Earth\u27s climate has undergone a global transition over the past four million years, from warm conditions with global surface temperatures about 3 °C warmer than today, smaller ice sheets and higher sea levels to the current cooler conditions. Tectonic changes and their influence on ocean heat transport have been suggested as forcing factors for that transition, including the onset of significant Northern Hemisphere glaciation 2.75 million years ago, but the ultimate causes for the climatic changes are still under debate. Here we compare climate records from high latitudes, subtropical regions and the tropics, indicating that the onset of large glacial/interglacial cycles did not coincide with a specific climate reorganization event at lower latitudes. The regional differences in the timing of cooling imply that global cooling was a gradual process, rather than the response to a single threshold or episodic event as previously suggested. We also find that high-latitude climate sensitivity to variations in solar heating increased gradually, culminating after cool tropical and subtropical upwelling conditions were established two million years ago. Our results suggest that mean low-latitude climate conditions can significantly influence global climate feedbacks

'Birds of a Feather Flock Together!': Rural Teacher Recruitment Policy and Retention in and for Hard-to-Staff Ugandan Schools

This chapter reports on findings from a qualitative case study conducted in four rural Ugandan public secondary schools in two districts fromMarch to October 2018. The study explored why some teachers stay while others leave rural teaching positions. Data collection methods included interviews, policy document analysis and researcher’s journal reflections. Interview data were collected from 20 teachers, 4 head teachers, 3 Parents & Teachers Association chairpersons, 2 Board of Governors chairpersons and 2 community leaders. A thematic analysis of data was pursued using an iterative process. The central findings reported in this chapter include the dynamic interaction between the Ministry of Education (MoE) policy, the government officials, schoolboards, head teachers and parents; the inherent trade-offs, massaged tensions and changing dynamics that have major impact on teacher retention, teacher quality and student outcomes; and the role of history of religion and culture in influencing the staffing of schools