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Key Advances (key + advance)
Selected AbstractsNetwork structural properties mediate the stability of mutualistic communitiesECOLOGY LETTERS, Issue 3 2008Toshinori Okuyama Abstract Key advances are being made on the structures of predator,prey food webs and competitive communities that enhance their stability, but little attention has been given to such complexity,stability relationships for mutualistic communities. We show, by way of theoretical analyses with empirically informed parameters, that structural properties can alter the stability of mutualistic communities characterized by nonlinear functional responses among the interacting species. Specifically, community resilience is enhanced by increasing community size (species diversity) and the number of species interactions (connectivity), and through strong, symmetric interaction strengths of highly nested networks. As a result, mutualistic communities show largely positive complexity,stability relationships, in opposition to the standard paradox. Thus, contrary to the commonly-held belief that mutualism's positive feedback destabilizes food webs, our results suggest that interplay between the structure and function of ecological networks in general, and consideration of mutualistic interactions in particular, may be key to understanding complexity,stability relationships of biological communities as a whole. [source] Stroke in patients with diabetes mellitusDIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 4 2004Boris N. Mankovsky Abstract The article's objective is to review the key advances in the scientific literature related to the association of stroke with diabetes mellitus and to summarize the current approaches to stroke prevention in diabetic patients. The key findings from the literature regarding stroke incidence in patients with diabetes, specific and nonspecific risk factors of stroke in the diabetic population, such as arterial hypertension, dyslipidemia, hyperglycemia, diabetes duration, diabetic complications, insulin resistance/hyperinsulinemia, course and outcome of stroke in subjects with diabetes and/or hyperglycemia, and the peculiarities of type, site and size of stroke in diabetic patients are discussed. The results of recent clinical trials aimed at correcting hyperglycemia, hypertension, and dyslipidemia, to prevent stroke in people with diabetes, are reviewed. The medical database Medline along with original articles from peer-reviewed journals were used for analysis. There is convincing evidence suggesting that diabetes mellitus represents a strong independent risk factor of stroke. The contribution of hyperglycemia to increased stroke risk is not proven. Data suggest an association of the full cluster of the insulin resistance syndrome and stroke. Diabetes is a risk factor mainly for ischemic stroke, while its association with hemorrhagic stroke remains controversial. Hyperglycemia is common in stroke patients, but it is not known whether it independently influences the course and outcome of stroke or merely reflects stroke severity and location. Aggressive control of arterial hypertension and dyslipidemia allows to decrease the risk of stroke in diabetic patients substantially, while the importance of glucose control for stroke prevention remains unproven. Copyright © 2004 John Wiley & Sons, Ltd. [source] Recent Advances in the Syntheses and Applications of Molybdenum and Tungsten Alkylidene and Alkylidyne Catalysts for the Metathesis of Alkenes and AlkynesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1-2 2007Richard Abstract The last several years have produced some key advances in the area of alkene and alkyne metathesis by high oxidation state alkylidene and alkylidyne complexes along with new applications in organic and polymer chemistry. In this review we cover some of these developments and applications. The first part of this review concerns developments in catalyst synthesis and new catalysts. The second part concerns notable applications in organic and polymer chemistry. We discuss only high oxidation state alkylidene and alkylidyne chemistry of relevance to alkene or alkyne metathesis reactions and favor studies in the homogeneous phase. [source] Osteoclastogenesis, Bone Resorption, and Osteoclast-Based TherapeuticsJOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2003Mone Zaidi Abstract Over the past decade, advances in molecular tools, stem cell differentiation, osteoclast and osteoblast signaling mechanisms, and genetically manipulated mice models have resulted in major breakthroughs in understanding osteoclast biology. This review focuses on key advances in our understanding of molecular mechanisms underlying the formation, function, and survival of osteoclasts. These include key signals mediating osteoclast differentiation, including PU.1, RANK, CSF-1/c-fms, and src, and key specializations of the osteoclast including HCl secretion driven by H+ -ATPase and the secretion of collagenolytic enzymes including cathepsin K and matrix metalloproteinases (MMPs). These pathways and highly expressed proteins provide targets for specific therapies to modify bone degradation. The main outstanding issues, basic and translational, will be considered in relation to the osteoclast as a target for antiresorptive therapies. [source] Click Chemistry-Led Advances in High Content Functional ProteomicsMOLECULAR INFORMATICS, Issue 11-12 2007Abstract The availability of complete genome sequences for numerous eukaryotic and prokaryotic organisms has inspired the advent of new methods to functionally characterize proteins on a global scale. Chemical approaches, in particular, have emerged as a powerful way to investigate the proteome, providing small-molecule probes that report on protein activity and Post-Translational Modification (PTM) state directly in complex biological samples. Many of the key advances made in chemical proteomics can be attributed to the development of efficient bio-orthogonal reactions such as the copper (I)-catalyzed Huisgen's azide,alkyne cycloaddition, a reaction commonly known as "Click Chemistry" (CC). The generation of "clickable" proteomics probes has removed the requirement for bulky reporter tags, thereby allowing access to more biologically relevant systems such as live cells or animals. The versatility of CC has also allowed for greater experimental efficiency, as different reporter tags (i.e., a fluorophore for detection or biotin for enrichment) can be appended to a single probe. Such advances have enabled researchers to identify protein activities dysregulated in disease states, assess the selectivity of enzyme inhibitors in vivo, and inventory specific PTMs on a proteome-wide scale. [source] Autism genetics: strategies, challenges, and opportunitiesAUTISM RESEARCH, Issue 1 2008Brian J. O'Roak Abstract Although genes have long been appreciated to play a critical role in determining the risk for pervasive developmental disorders, the specific transcripts contributing to autism spectrum disorders (ASD) have been quite difficult to characterize. However, recent findings are now providing the first insights into the molecular mechanisms underlying these syndromes and have begun to shed light on the allelic architecture of ASD. In this article, we address what is known about the relative contributions of various types of genetic variation to ASD, consider the obstacles facing gene discovery in this complex disorder, and evaluate the common methodologies employed to address these issues, including linkage, molecular and array-based cytogenetics, and association strategies. We review the current literature, highlighting recent findings implicating both rare mutations and common genetic polymorphisms in the etiology of autism. Finally, we describe key advances in genomic technologies that are transforming all areas of human genetics and consider both the opportunities and challenges for autism research posed by these rapid changes. [source] | |||||||||||||