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1.
On 12-15 May 2011, a diverse group of students, researchers and practitioners from across Canada and around the world met in Banff, Alberta, to discuss the many facets of biodiversity science at the 6th Annual Meeting of the Canadian Society for Ecology and Evolution.  相似文献   

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Chitosomes: past, present and future   总被引:4,自引:0,他引:4  
José Ruiz-Herrera's discovery that chitin microfibrils could be made by a fungal extract paved the way for elucidating the intracellular location of chitin synthetase. In collaboration with Charles Bracker, chitosomes were identified as the major reservoir of chitin synthetase in fungi. Unique in size, buoyant density, and membrane thickness, chitosomes were found in a wide range of fungi. Their reversible dissociation into 16S subunits is another unique property of chitosomes. These 16S subunits are the smallest molecular entities known to retain chitin synthetase activity. Further dissociation leads to complete loss of activity. From studies with secretory mutants, yeast researchers concluded that chitosomes were components of the endocytosis pathway. However, key structural and enzymatic characteristics argue in favor of the chitosome being poised for exocytotic delivery rather than endocytotic recycling. The chitosome represents the main vehicle for delivering chitin synthetase to the cell surface. An immediate challenge is to elucidate chitosome ontogeny and the role of proteins encoded by the reported chitin synthetase genes in the structure or function of chitosomes. The ultimate challenge would be to understand how the chitosome integrates with the cell surface to construct the organized microfibrillar skeleton of the fungal cell wall.  相似文献   

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Immunotherapy: past,present and future   总被引:15,自引:0,他引:15  
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Molecular methods of taxonomy and phylogeny have changed the way in which life on earth is viewed; they have allowed us to transition from a eukaryote-centric (five-kingdoms) view of the planet to one that is peculiarly prokarote-centric, containing three kingdoms, two of which are prokaryotic unicells. These prokaryotes are distinguished from their eukaryotic counterparts by their toughness, tenacity and metabolic diversity. Realization of these features has, in many ways, changed the way we feel about life on earth, about the nature of life past and about the possibility of finding life elsewhere. In essence, the limits of life on this planet have expanded to such a degree that our thoughts of both past and future life have been altered. The abilities of prokaryotes to withstand many extreme conditions has led to the term extremophiles, used to describe the organisms that thrive under conditions thought just a few years ago, to be inconsistent with life. Perhaps the most extensive adaptation to extreme conditions, however, is represented by the ability of many bacteria to survive nutrient conditions not compatible with eukaryotic life. Prokaryotes have evolved to use nearly every redox couple that is in abundance on earth, filling the metabolic niches left behind by the oxygen-using, carbon-eating eukaryotes. This metabolic plasticity leads to a common feature in physically stratified environments of layered microbial communities, chemical indicators of the metabolic diversity of the prokaryotes. Such 'metabolic extremophily' forms a backdrop by which we can view the energy flow of life on this planet, think about what the evolutionary past of the planet might have been, and plan ways to look for life elsewhere, using the knowledge of energy flow on earth.  相似文献   

6.
Ranavirus: past, present and future   总被引:1,自引:0,他引:1  
Emerging infectious diseases are a significant threat to global biodiversity. While historically overlooked, a group of iridoviruses in the genus Ranavirus has been responsible for die-offs in captive and wild amphibian, reptile and fish populations around the globe over the past two decades. In order to share contemporary information on ranaviruses and identify critical research directions, the First International Symposium on Ranaviruses was held in July 2011 in Minneapolis, MN, USA. Twenty-three scientists and veterinarians from nine countries examined the ecology and evolution of ranavirus-host interactions, potential reservoirs, transmission dynamics, as well as immunological and histopathological responses to infection. In addition, speakers discussed possible mechanisms for die-offs, and conservation strategies to control outbreaks.  相似文献   

7.
Biodiversity: past, present, and future   总被引:2,自引:0,他引:2  
Data from the fossil record are used to illustrate biodiversity in the past and estimate modern biodiversity and loss. This data is used to compare current rates of extinction with past extinction events. Paleontologists are encouraged to use this data to understand the course and consequences of current losses and to share this knowledge with researchers interested in conservation and ecology.  相似文献   

8.
Plague: past, present, and future   总被引:2,自引:0,他引:2  
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Studies of foraging behaviour have proliferated over the past 30 years. Two schools of thought have emerged, one focusing on theoretical aspects (so-called 'optimal foraging theory'), the other on empirical studies. We summarize both, showing how they have evolved and begun to coalesce during the past decade. The emerging new framework is more complex than previous models, combining theory with observation. Modern phylogenetic methods promise new insights into how animal foraging has evolved.  相似文献   

13.
Francisella tularensis is a Gram negative intracellular pathogen that causes the highly debilitating or fatal disease tularemia. F. tularensis can infect a wide range of animals and can be transmitted to humans in a variety of ways, the most common being by the bite of an infected insect or arthropod vector. The attenuated F. tularensis live vaccine strain (LVS) has been used previously under investigational new drug status to vaccinate at-risk individuals. However the history of the strain and lack of knowledge regarding the basis of attenuation has so far prevented its licensing. Therefore the focus of current research is on producing a new vaccine against tularemia that would be suitable for licensing.  相似文献   

14.
The rainforests are the great green heart of Africa, and present a unique combination of ecological, climatic and human interactions. In this synthesis paper, we review the past and present state processes of change in African rainforests, and explore the challenges and opportunities for maintaining a viable future for these biomes. We draw in particular on the insights and new analyses emerging from the Theme Issue on ‘African rainforests: past, present and future’ of Philosophical Transactions of the Royal Society B. A combination of features characterize the African rainforest biome, including a history of climate variation; forest expansion and retreat; a long history of human interaction with the biome; a relatively low plant species diversity but large tree biomass; a historically exceptionally high animal biomass that is now being severely hunted down; the dominance of selective logging; small-scale farming and bushmeat hunting as the major forms of direct human pressure; and, in Central Africa, the particular context of mineral- and oil-driven economies that have resulted in unusually low rates of deforestation and agricultural activity. We conclude by discussing how this combination of factors influences the prospects for African forests in the twenty-first century.  相似文献   

15.
Chronic pain is a classic example of gene × environment interaction: inflammatory and/or nerve injuries are known or suspected to be the etiology of most chronic pain syndromes, but only a small minority of those subjected to such injuries actually develop chronic pain. Once chronic pain has developed, pain severity and analgesic response are also highly variable among individuals. Although animal genetics studies have been ongoing for over two decades, only recently have comprehensive human twin studies and large-scale association studies been performed. Here, I review recent and accelerating progress in, and continuing challenges to, the identification of genes contributing to such variability. Success in this endeavor will hopefully lead to both better management of pain using currently available therapies and the development and/or prioritizing of new ones.  相似文献   

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CellML: its future, present and past   总被引:15,自引:0,他引:15  
Advances in biotechnology and experimental techniques have lead to the elucidation of vast amounts of biological data. Mathematical models provide a method of analysing this data; however, there are two issues that need to be addressed: (1) the need for standards for defining cell models so they can, for example, be exchanged across the World Wide Web, and also read into simulation software in a consistent format and (2) eliminating the errors which arise with the current method of model publication. CellML has evolved to meet these needs of the modelling community. CellML is a free, open-source, eXtensible markup language based standard for defining mathematical models of cellular function. In this paper we summarise the structure of CellML, its current applications (including biological pathway and electrophysiological models), and its future development—in particular, the development of toolsets and the integration of ontologies.  相似文献   

19.
Calcium signalling: past, present and future   总被引:8,自引:0,他引:8  
Ca2+ is a universal second messenger controlling a wide variety of cellular reactions and adaptive responses. The initial appreciation of Ca2+ as a universal signalling molecule was based on the work of Sydney Ringer and Lewis Heilbrunn. More recent developments in this field were critically influenced by the invention of the patch clamp technique and the generation of fluorescent Ca2+ indicators. Currently the molecular Ca2+ signalling mechanisms are being worked out and we are beginning to assemble a reasonably complete picture of overall Ca2+ homeostasis. Furthermore, investigations of organellar Ca2+ homeostasis have added complexity to our understanding of Ca2+ signalling. The future of the Ca2+ signalling field lies with detailed investigations of the integrative function in vivo and clarification of the pathology associated with malfunctions of Ca2+ signalling cascades.  相似文献   

20.
S Carrière  E Ryten 《CMAJ》1993,148(9):1528-1532
In this article, the president of the Association of Canadian Medical Colleges (ACMC) and its director of research review the issues that have confronted ACMC since its inception: the founding of ACMC; development of the clinical teaching unit; creation of the Medical Research Council and expansion of the research mission; the Royal Commission on Health Services and the founding of new faculties of medicine; ACMC''s in-house research program; accreditation and ACMC''s links with medical education in the United States; and French-language medical education in Canada. The review points out the perennial nature of many of these issues, and how often perceived solutions to the problems later become problems themselves. It ends on the optimistic note that ACMC can successfully meet the challenges of the future.  相似文献   

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