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81.
To increase our understanding of the role of new X-chromosome mutations in adaptive evolution, single-X Drosophila melanogaster males were mated with attached-X chromosome females, allowing the male X chromosome to accumulate mutations over 28 generations. Contrary to our hypothesis that male viability would decrease over time, due to the accumulation and expression of X-linked recessive deleterious mutations in hemizygous males, viability significantly increased. This increase may be attributed to germinal selection and to new X-linked beneficial or compensatory mutations, possibly supporting the faster-X hypothesis. 相似文献
82.
Felista L. Tansi Ronny Rüger Ansgar M. Kollmeier Markus Rabenhold Frank Steiniger Roland E. Kontermann Ulf K. Teichgraeber Alfred Fahr Ingrid Hilger 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(6):1389-1400
Background
Endoglin (CD105) is overexpressed on tumor cells and tumor vasculatures, making it a potential target for diagnostic imaging and therapy of different neoplasms. Therefore, studies on nanocarrier systems designed for endoglin-directed diagnostic and drug delivery purposes would expose the feasibility of targeting endoglin with therapeutics.Methods
Liposomes carrying high concentrations of a near-infrared fluorescent dye in the aqueous interior were prepared by the lipid film hydration and extrusion procedure, then conjugated to single chain antibody fragments either selective for murine endoglin (termed mEnd-IL) or directed towards human endoglin (termed hEnd-IL). A combination of Dynamic Light Scattering, electron microscopy, cell binding and uptake assays, confocal microscopy and in vivo fluorescence imaging of mice bearing xenografted human breast cancer and human fibrosarcoma models were implemented to elucidate the potentials of the liposomes.Results
The mEnd-IL and hEnd-IL were highly selective for the respective murine- and human endoglin expressing cells in vitro and in vivo. Hence, the hEnd-IL bound distinctly to the tumor cells and enabled suitable fluorescence imaging of the tumors, whereas the mEnd-IL bound the tumor vasculature, but also to the liver, kidney and lung vasculature of mice.Conclusions
The work highlights key differences between targeting vascular (murine) and neoplastic (human) endoglin in animal studies, and suggests that the hEnd-IL can serve as a delivery system that targets human endoglin overexpressed in pathological conditions.General significance
The endoglin-targeting liposomes presented herewith represent strategic tools for the future implementation of endoglin-directed neoplastic and anti-angiogenic therapies. 相似文献83.
Antonio B. S. Poléo Sigurd A. Osxnevad Kjartan Össtbye Erik Heibo Ronny A. Andersen L. Asbjøm Vøllestad 《Ecography》1995,18(3):225-229
Crucian carp Carassius carassius was sampled during 1993 and 1994 in 21 lakes and ponds in east Norway In 10 of these lakes and ponds no piscivorous fish species was present, and in the remaining 11 lakes and ponds predators such as perch Perca fluvtalilis. pike Esox lucius, and trout Salmo trutta were common In general, crucian carp was larger in the lakes with predators than in those without predators The relative body depth (body height/body length) of crucian carp was significantly deeper in populations sympatric with predators (mean 0 358), compared to allopatric populations (mean 0 286) The variation in relative body depth was larger among the sympatric populations than among the allopatric populations The observed difference in relative body depth may be due to 1) predator induced changes m body morphology, 2) increased growth rates in lakes containing predator due to reduced intraspecific competition, and 3) size-selective predation 相似文献
84.
Strains of Mycobacterium bovis, M. bovis BCG, and M. tuberculosis, including a so-called Canetti strain, were analyzed by means of two-dimensional immunoelectrophoresis (2D-IE), 2D-IE combined with enzyme staining, and multilocus enzyme electrophoresis (MEE). The results demonstrated a close antigentic and enzymatic resemblance among all the strains tested, even though the BCG strains could be divided into two groups based on the presence of one precipitinogen. Eight of the precipitinogens were shown to correspond to enzymes in M. bovis BCG and 10 in M. tuberculosis. Thus, catalase, isocitrate dehydrogenase, malate dehydrogenase, peroxidase, and several others were identified. By means of MEE the strains of M. tuberculosis, M. bovis, and M. bovis BCG could be differentiated. The analyses further indicated that the M. tuberculosis strain Canetti was more closely related to M. bovis than to M. tuberculosis. 相似文献
85.
From near extinction to diversification by means of a shift in pollination mechanism in the gymnosperm relict Ephedra (Ephedraceae,Gnetales)
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Kristina Bolinder Aelys M. Humphreys Johan Ehrlén Ronny Alexandersson Stefanie M. Ickert‐Bond Catarina Rydin 《Botanical journal of the Linnean Society. Linnean Society of London》2016,180(4):461-477
Pollination in gymnosperms is usually accomplished by means of wind, but some groups are insect‐pollinated. We show that wind and insect pollination occur in the morphologically uniform genus Ephedra (Gnetales). Based on field experiments over several years, we demonstrate distinct differences between two Ephedra species that grow in sympatry in Greece in pollen dispersal and clump formation, insect visitations and embryo formation when insects are denied access to cones. Ephedra distachya, nested in the core clade of Ephedra, is anemophilous, which is probably the prevailing state in Ephedra. Ephedra foeminea, sister to the remaining species of the genus, is entomophilous and pollinated by a range of diurnal and nocturnal insects. The generalist entomophilous system of E. foeminea, with distinct but infrequent insect visitations, is in many respects similar to that reported for Gnetum and Welwitschia and appears ancestral in Gnetales. The Ephedra lineage is well documented already from the Early Cretaceous, but the diversity declined dramatically during the Late Cretaceous, possibly to near extinction around the Cretaceous–Palaeogene boundary. The clade imbalance between insect‐ and wind‐pollinated lineages is larger than expected by chance and the shift in pollination mode may explain why Ephedra escaped extinction and began to diversify again. 相似文献
86.
87.
Anna E. Rapp Ronny Bindl Stefan Recknagel Annika Erbacher Ingo Müller Hubert Schrezenmeier Christian Ehrnthaller Florian Gebhard Anita Ignatius 《PloS one》2016,11(2)
Following bone fracture, the repair process starts with an inflammatory reaction at the fracture site. Fracture healing is disturbed when the initial inflammation is increased or prolonged, whereby, a balanced inflammatory response is anticipated to be crucial for fracture healing, because it may induce down-stream responses leading to tissue repair. However, the impact of the immune response on fracture healing remains poorly understood. Here, we investigated bone healing in NOD/scid-IL2Rγcnull mice, which exhibit severe defects in innate and adaptive immunity, by biomechanical testing, histomorphometry and micro-computed tomography. We demonstrated that NOD/scid-IL2Rγcnull mice exhibited normal skeletal anatomy and a mild bone phenotype with a slightly reduced bone mass in the trabecular compartment in comparison to immunocompetent Balb/c mice. Fracture healing was impaired in immunodeficient NOD/scid-IL2Rγcnull mice. Callus bone content was unaffected during the early healing stage, whereas it was significantly reduced during the later healing period. Concomitantly, the amount of cartilage was significantly increased, indicating delayed endochondral ossification, most likely due to the decreased osteoclast activity observed in cells isolated from NOD/scid-IL2Rγcnull mice. Our results suggest that—under aseptic, uncomplicated conditions—the immediate immune response after fracture is non-essential for the initiation of bone formation. However, an intact immune system in general is important for successful bone healing, because endochondral ossification is delayed in immunodeficient NOD/scid-IL2Rγcnull mice. 相似文献
88.
Harry Cuppens Eric egius Pablo Cabello Peter Marynen Chris De Boeck Ronny Decorte Jean-Pierre Fryns Ephraim Eggermont Herman Van den Berghe Jean-Jacques Cassiman 《Human genetics》1990,85(4):402-403
Summary Using Southern blotting and the polymerase chain reaction, the prevalence of the haplotypes for XV2c, CS7, KM19 and D9 on
CF and on normal chromosomes could be determined in 35 Belgian families. A set of primers complementary to the DNA sequence
of the CF gene around the ΔF508 deletion was used to amplify this particular segment of the gene. In a total of 57 families,
deletion screening showed that 69 out of 116 CF chromosomes (59.5%) carried the ΔF508 deletion. Both the ΔF508 deletion and
another mutation(s) showed strong association with the haplotype 1-2-2-2. 相似文献
89.
J. I. Ronny Larsson 《Systematic parasitology》1988,11(1):3-17
The paper treats the taxonomy of the genus Systenostrema Hazard & Oldacre, 1975, starting with an ultrastructural investigation of two new species, parasitic in larvae of the dragonflies Aeshna grandis and Libellula quadrimaculata, collected in Sweden. The two species are identical in pathology and presporal stages, but differ in the shape of spores and sporophorous vesicles, the fine structure of the spores, and numerical characters. The new species, which are named S. alba and S. candida, are compared to the octosporoblastic microsporidia parasitic in Odonata. An emended diagnosis of the genus Systenostrema is given, together with a taxonomic summary. The new combinations S. trichostegiae for Thelohania trichostegiae Baudoin, 1969 and Amblyospora capillata for T. capillata Larsson, 1983 are established. 相似文献
90.
Susanne Löfgren Stina Ekman Ylva Terelius Ronny Fransson-Steen 《Acta veterinaria Scandinavica》2008,50(1):47