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101.
Julia Binkenstein Alexandra‐Maria Klein Thorsten Assmann François Buscot Alexandra Erfmeier Keping Ma Katherina A. Pietsch Karsten Schmidt Thomas Scholten Tesfaye Wubet Helge Bruelheide Andreas Schuldt Michael Staab 《Ecography》2018,41(6):1013-1023
Negative relationships between species richness and elevation are common and attributed to changes in single environmental properties associated to elevation, such as temperature and habitat area. However, research has lacked taxonomic breadth and comprehensive elevation studies that consider multiple groups from different trophic levels are rare. We thus analysed 24 groups of plants, arthropods, and microorganisms grouped into six trophic guilds (predators, detritivores, herbivores, plants, bacteria and fungi) along a relatively short elevational gradient (~600 m) in a subtropical forest in south‐east China. The total species richness of all organisms was not related to elevation, nor was the richness of plants, herbivores or microorganisms. However, species richness and abundance in two major trophic guilds of arthropods changed with elevation, which was mediated by changes in elevation‐associated habitat properties. Specifically, deadwood mass increased with elevation, which increased detritivore richness indirectly via detritivore abundance, thus supporting the ‘more individuals hypothesis’. In contrast, lower predator richness at higher elevations was directly related to lower mean temperatures, which had no effect on abundance. Our study demonstrates that even along relatively short gradients, elevation can have strong direct and abundance‐mediated effects on species richness, but with effects varying from positive to negative signs depending on local resource availability and the characteristics of groups or trophic guilds. If elevation positively influences local environmental properties that benefit a given group, richness can increase towards higher elevations. Thus, the effect of global change in mountainous regions should be evaluated within the local environmental context using multi‐taxon approaches. 相似文献
102.
Diceratias trilobus Balushkin and Fedorov, 1986, was described from a single female specimen, 122 mm standard length, collected from off the east of Honshu, Japan, in 1975. Since that time the holotype has remained the only known representative of the species. Recently, however, a number of additional specimens have become available. This new material is described below and compared with the holotype. 相似文献
103.
In this study, carp Cyprinus carpio were injected with various steroid compounds, including synthetic and natural progestogens and the glucocorticoid cortisol, to investigate effects on leucocytes isolated from their kidneys. Injection of cortisol led to an increased spleeno-somatic index (I(S)) on day 21 post-injection (pi) and immunosuppressive effects measured as decreased nitric oxide (NO) production and increased arginase activity in isolated leucocytes on days 14 and 21 pi, respectively. Moreover, reduced NO production was also observed after injection of the synthetic progestogens, levonorgestrel (LEV) and medroxyprogesterone acetate. In addition, LEV influenced arginase activity in head kidney cells on day 14 and day 21 pi. This study is the first demonstration in fishes that the application of these steroid compounds in vivo affects NO production and arginase activity of isolated leucocytes. 相似文献
104.
Reif JC Gowda M Maurer HP Longin CF Korzun V Ebmeyer E Bothe R Pietsch C Würschum T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(5):961-970
Improvement of end-use quality in bread wheat (Triticum aestivum L.) depends on a thorough understanding of the genetic basis of important quality traits. The main goal of our study was
to investigate the genetic basis of 1,000-kernel weight, protein content, sedimentation volume, test weight, and starch concentration
using an association mapping approach. We fingerprinted 207 diverse European elite soft winter wheat lines with 115 SSR markers
and evaluated the genotypes in multi-environment trials. The principal coordinate analysis revealed absence of a clear population
but presence of a family structure. Therefore, we used linear mixed models and marker-based kinship matrices to correct for
family structure. In genome-wide scans, we detected main effect QTL for all five traits. In contrast, epistatic QTL were only
observed for sedimentation volume and test weight explaining a small proportion of the genotypic variation. Consequently,
our findings suggested that integrating epistasis in marker-assisted breeding will not lead to substantially increased selection
gain for quality traits in soft winter wheat. 相似文献
105.
Abraham Zepeda-Moreno Isabel Taubert Isabelle Hellwig Van Hoang Larissa Pietsch Vinoth Kumar Lakshmanan Wolfgang Wagner Anthony D Ho 《Cell Adhesion & Migration》2011,5(3):215-219
Cell adhesion is an important part of many complex biological processes. It plays crucial roles in cancer, development and maintenance of stem cell compartment. The measurement of adhesion under experimental conditions might provide important information for cell biology. There are several protocols to measure adhesion, usually based on washing or shaking to remove non-adherent cells. Here, we describe a quantification method based on gravitational force to measure adhesion in a 96-well format. Non-adherent cells are separated and only vital cells are quantified with a colorimetric assay. This assay can be used especially when the “anti-adhesion” effect is present only for a short period of time like is the case of peptides or cytokines since it provides a trap for non-adherent cells in a way that they can not touch again the adherent surface. As examples we provide the quantification of cell-cell interaction with blocking antibodies anti-CD44 in hematopoietic stem cells and the effect of the stromal cell derived factor-1 (SDF-1) in the Jurkat cell line when they are in contact with mesenchymal stromal cells. This method facilitates fast and reliable measurement of cell adhesion in multiwell format for screening assays.Key words: adhesion assay, adhesion, SDF-1, CD44, hematopoietic stem cells, leukemia cell lines 相似文献
106.
Background
Several felids are endangered and threatened by the illegal wildlife trade. Establishing geographic origin of tissues of endangered species is thus crucial for wildlife crime investigations and effective conservation strategies. As shown in other species, stable isotope analysis of hydrogen and oxygen in hair (δDh, δ18Oh) can be used as a tool for provenance determination. However, reliably predicting the spatial distribution of δDh and δ18Oh requires confirmation from animal tissues of known origin and a detailed understanding of the isotopic routing of dietary nutrients into felid hair.Methodology/Findings
We used coupled δDh and δ18Oh measurements from the North American bobcat (Lynx rufus) and puma (Puma concolor) with precipitation-based assignment isoscapes to test the feasibility of isotopic geo-location of felidae. Hairs of felid and rabbit museum specimens from 75 sites across the United States and Canada were analyzed. Bobcat and puma lacked a significant correlation between H/O isotopes in hair and local waters, and also exhibited an isotopic decoupling of δ18Oh and δDh. Conversely, strong δD and δ18O coupling was found for key prey, eastern cottontail rabbit (Sylvilagus floridanus; hair) and white-tailed deer (Odocoileus virginianus; collagen, bone phosphate).Conclusions/Significance
Puma and bobcat hairs do not adhere to expected pattern of H and O isotopic variation predicted by precipitation isoscapes for North America. Thus, using bulk hair, felids cannot be placed on δ18O and δD isoscapes for use in forensic investigations. The effective application of isotopes to trace the provenance of feline carnivores is likely compromised by major controls of their diet, physiology and metabolism on hair δ18O and δD related to body water budgets. Controlled feeding experiments, combined with single amino acid isotope analysis of diets and hair, are needed to reveal mechanisms and physiological traits explaining why felid hair does not follow isotopic patterns demonstrated in many other taxa. 相似文献107.
Michael Gütschow Markus Pietsch Andrea Themann Janine Fahrig Bärbel Schulze 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):341-347
A series of substituted 2,4,5-triphenylisothiazol-3(2H)-one 1,1-dioxides 9 was synthesized and investigated as inhibitors of human leukocyte elastase (HLE). All compounds were found to inhibit HLE in a time-dependent manner and most of them exhibited kobs/[I] values > 300 M? 1s? 1. The most potent 3-oxosultam of this series was 9l (kobs/[I] = 2440 M? 1s? 1). Kinetic investigations performed with 9g and different substrate concentrations did not allow to clearly distinguish between a competitive or noncompetitive mode of inhibition. A more complex interaction is supported by the failure of a linear dependency of kobs values on the inhibitor concentration. 相似文献
108.
Markus Pietsch Robert Wodtke Jens Pietzsch Reik Löser 《Bioorganic & medicinal chemistry letters》2013,23(24):6528-6543
Tissue transglutaminase (transglutaminase 2) is a multifunctional enzyme with many interesting properties resulting in versatile roles in both physiology and pathophysiology. Herein, the particular involvement of the enzyme in human diseases will be outlined with special emphasis on its role in cancer and in tissue interactions with biomaterials. Despite recent progress in unraveling the different cellular functions of transglutaminase 2, several questions remain. Transglutaminase 2 features in both confirmed and some still ambiguous roles within pathological conditions, raising interest in developing inhibitors and imaging probes which target this enzyme. One important prerequisite for identifying and characterizing such molecular tools are reliable assay methods to measure the enzymatic activity. This digest Letter will provide clarification about the various assay methods described to date, accompanied by a discussion of recent progress in the development of inhibitors and imaging probes targeting transglutaminase 2. 相似文献
109.
110.