7 research outputs found
Native diversity buffers against severity of non-native tree invasions
Determining the drivers of non-native plant invasions is critical for managing native ecosystems and limiting the spread of invasive species1,2. Tree invasions in particular have been relatively overlooked, even though they have the potential to transform ecosystems and economies3,4. Here, leveraging global tree databases5â7, we explore how the phylogenetic and functional diversity of native tree communities, human pressure and the environment influence the establishment of non-native tree species and the subsequent invasion severity. We find that anthropogenic factors are key to predicting whether a location is invaded, but that invasion severity is underpinned by native diversity, with higher diversity predicting lower invasion severity. Temperature and precipitation emerge as strong predictors of invasion strategy, with non-native species invading successfully when they are similar to the native community in cold or dry extremes. Yet, despite the influence of these ecological forces in determining invasion strategy, we find evidence that these patterns can be obscured by human activity, with lower ecological signal in areas with higher proximity to shipping ports. Our global perspective of non-native tree invasion highlights that human drivers influence non-native tree presence, and that native phylogenetic and functional diversity have a critical role in the establishment and spread of subsequent invasions
Nine months of combined training improves ex vivo skeletal muscle metabolism in individuals with type 2 diabetes
Context: Type 2 diabetes (T2D) has features of disordered lipid and glucose metabolism, due in part to reduced mitochondrial content. Objective: Our objective was to investigate effects of different types of exercise on mitochondrial content and substrate oxidation in individuals with T2D (ancillary study of the randomized controlled trial Health Benefits of Aerobic and Resistance Training in Individuals with Type 2 Diabetes, HART-D). Intervention: T2D individuals were randomized to aerobictraining (AT, n = 12), resistance training (RT, n = 18), combination training(ATRT, n = 12), or nonexercise control (n = 10). Blooddraws, peakoxygen consumption tests, dual-energy x-ray absorptiometry scans and muscle biopsies of vastus lateralis were performed before and after 9 months. Ex vivo substrate oxidations ((CO2)-C-14), mitochondrial content, and enzyme activities were measured. Glycated hemoglobin A(1c) and free fatty acids were also determined. Results: Mitochondrial content increased after RT and ATRT. Octanoate oxidation increased after AT and ATRT, whereas palmitate, pyruvate, and acetate oxidations increased in all exercise groups. Exercise-induced responses in mitochondrial DNA were associated with improvements in peak oxygen consumption, beta-hydroxyacyl-coenzyme A dehydrogenase activity, and palmitate oxidation. Conclusions: Nine months of AT and RT significantly improved most aspects of skeletal muscle mitochondrial content and substrate oxidation, whereas the combination improved all aspects. These exercise responses were associated with clinical improvements, indicating that long-term training, especially combination, is an effective lifestyle therapy for individuals with T2D by way of improving muscle substrate metabolism. (J Clin Endocrinol Metab 98: 1694-1702, 2013
Evidence for subtypic determinants in the HLA-DW3 cluster.
This study was undertaken to get more insight into the previously suggested heterogeneity of the HLA-DW3 cluster. Preliminary evidence of DW3 heterogeneity was derived from results of intrafamilial mixed lymphocyte culture tests (MLC) where cells of apparently homozygous offspring revealed unexpected stimulations of one of the parents' cells. Therefore, 15 different homozygous typing cells (HTCs) of DW3 specificity were tested against 43 HLA-DW3 heterozygous individuals. The response patterns of the 43 HLA-DW3 heterozygous cells toward 13 HTCs lead to the definition of at least three groups of DW3 stimulating cells. According to these patterns, four groups of responding cells could be classified. These results were confirmed by a MLC checkerboard experiment running all DW3-HTCs against each other. Discussing all possible explanations for these observations, the authors conclude that the existence of DW3 subtypes having some properties in common is the most likely interpretation of the results obtained. Family segregation studies will be needed to define the genotypic situation of the DW3 cluster
Inflammatory biomarkers in Alzheimer's disease plasma
Plasma biomarkers for Alzheimer's disease (AD) diagnosis/stratification are a "Holy Grail" of AD research and intensively sought; however, there are no well-established plasma markers. A hypothesis-led plasma biomarker search was conducted in the context of international multicenter studies. The discovery phase measured 53 inflammatory proteins in elderly control (CTL; 259), mild cognitive impairment (MCI; 199), and AD (262) subjects from AddNeuroMed. Ten analytes showed significant intergroup differences. Logistic regression identified five (FB, FH, sCR1, MCP-1, eotaxin-1) that, age/APOÎľ4 adjusted, optimally differentiated AD and CTL (AUC: 0.79), and three (sCR1, MCP-1, eotaxin-1) that optimally differentiated AD and MCI (AUC: 0.74). These models replicated in an independent cohort (EMIF; AUC 0.81 and 0.67). Two analytes (FB, FH) plus age predicted MCI progression to AD (AUC: 0.71). Plasma markers of inflammation and complement dysregulation support diagnosis and outcome prediction in AD and MCI. Further replication is needed before clinical translation
Review- Alternatives for the separation of drug enantiomers: ibuprofen as a model compound
The origins of Odense â new aspects of early urbanisation in southern Scandinavia
The article presents an updated study of the centuries prior to Odenseâs traditional âbirth certificateâ of AD 988, resulting in a new model for the urbanisation of Odense. The conclusion reached is that there was activity of a permanent and possibly urban character in Odense from the end of the late eighth century until the late tenth century. The townâs development can be followed through three phases. Phases 1 and 2 cover the periods AD 700â900 and AD 900â100, respectively, while phase 3 covers the period AD 1000-1101. During phases 1 and 2, the proto-town develops through bottomup processes, such as network, crafts and possibly trade. After AD 1000, Odense develops into a town proper, under royal influence. The model from Odense provides the background for a fresh view of urbanisation in southern Scandinavia in general. A three-phase model is proposed. Phase 0 constitutes the emporia of the eighthâninth century, which perhaps primarily is satellites in a trading network controlled from the south. Phase 1 takes the form of locally initiated and based incipient urbanisation extending from the end of the eighth century until the tenth century. Phase 2 comprises the royally established towns from around AD 1000 onwards