Growth,phenology, and biomass allocation of alien Solidago species in central Europe

Plant invasion is a major threat to the integrity of an ecosystem. Exceptionally successful invaders in Europe are the American species of Solidago genus. In this study we examined growth, reproduction, and phenology of Solidago species, of American origin, growing in central Europe (S. altissima, S. canadensis, S. gigantea, S. graminifolia). These taxa were compared with two native species: Solidago virgaurea and Tanacetum vulgare. We observed high differentiation in height, number of shoots, and biomass production between individuals within taxa. Generally, the invasive species produced substantially (two to five times) more biomass than the native ones, being statistically significant in the comparison of alien Solidago graminifolia and S. gigantea versus native S. virgaurea and T. vulgare. The ratio of biomass of reproductive parts to overall biomass varied considerably among years, but generally the lowest one was for Solidago altissima, and the highest for S. graminifolia. It shows a lack of a clear pattern of differentiation between alien and native species in terms of biomass investment in reproduction. We observed a general tendency of allocation of a major part of biomass in rhizomes by phalanx species (S. graminifolia and S. gigantea), while species with guerrilla strategy (S. altissima and S. canadensis) invested more biomass in stems and leaves. However, because of the high variability there was no clear, stable pattern of statistically significant differences between these two groups. The results suggest that S. graminifolia reveals a strong potential of invasion, in spite of its, so far limited, distribution in Europe.     

Cellular architecture and migration behavior of fibroblast cells on polyhydroxyoctanoate (PHO): A natural polymer of bacterial origin

Biodegradable and biocompatible novel materials of natural origin are gaining more and more attention in recent years. These so called biopolymers, characterized by their biointegrity and biocompatibility, find completely new and promising applications in biomedical sciences. The presented work focuses on the medium chain length elastomeric polyhydroxyalkanoate biopolymer—polyhydroxyoctanoate (PHO). This biopolymer is fully biodegradable without formation of harmful byproducts.We investigated PHO's physical properties with nanoindentation technique and scratch testing to determine Young's modulus and friction coefficient. Further, the work focused on the impact of PHO, used as growth substrate, on the physiology and morphology of mouse embryonic fibroblast cells (MEF 3T3). Application of fluorescent staining protocols and advanced microscopic techniques allowed to study the morphological changes in the cytoskeletons of cells grown on PHO and also gave an insight into their migration strategies on the polymer surface. We found that PHO exhibits no cellular cytotoxicity, similarly to a glass substrate. MEF cells spread better on glass surface than on each tested PHO substrate though there was almost no difference between PHO substrates cast from different solvents. However, a detailed analysis of actin and microtubule cytoskeletal architecture reveals changes in the density of actin and microtubular networks. Migration of MEF cells on PHO substrates was slower than on the glass substrate. To elucidate the molecular mechanisms of observed changes in cytoskeletal architecture and migration parameters can be of special interest for future medical application of PHO polymer.     

Natural Monoterpenes: Much More than Only a Scent

Terpenes are a widespread group of secondary metabolites that can be found in various family plants such as the Lamiaceae. In view of their numerous valuable biological activities, the industrial production of concrete terpenes and essential oils rich in the substances is intensively studied. Monoterpenes constitute a significant part of the whole group of the aforementioned secondary metabolites. This is due to their numerous biological activities and their ability to permeate the skin. Despite the fact that these substances have gain popularity, they are not comprehensively characterized. The presented review is based on studies of the biological activities of the most important monoterpenes and the essential oils rich in these compounds. The authors focused attention on antioxidant activity, inhibition towards acetyl‐ and butyrylcholinesterase, and α‐amylase and α‐glucosidase, antifungal, hepatoprotective, sedative properties, and their skin permeation enhancement.     

Changes in water status and water distribution in maturing lupin seeds studied by MR imaging and NMR spectroscopy

The changes in water distribution in maturing lupin (Lupinus luteus L.) seeds were visualized with magnetic resonance imaging (MRI). MRI data showed local inhomogeneities of water distribution inside the seed. At the late seed-filling stage the most intense signal was detected in the seed coat and the outer parts of cotyledons in the hilum area, but during maturation drying the decline in MR image intensity was faster in the outer part of the seed than in the central part. The changes in water status were characterized by NMR spectroscopy. Analyses of T(2) relaxation times revealed a three-component water proton system in maturing lupin seeds. Three populations of protons found during seed maturation, each with a different magnetic environment causing a different relaxation rate, were correlated with three fractions of water (structural, intracellular, and extracellular) that were observed during seed germination. This study provides evidence that lupin seeds have similar states of the different water components with regard to seed moisture content at two distinct physiological stages, seed maturation and germination. The unique feature of maturing lupin seeds is the presence of the high (1)H-NMR signal in areas corresponding to the vascular bundles. Tissue localization of dehydrins showed the presence of dehydrin protein in the area of vascular tissue. An anti-dehydrin antibody detected three polypeptides in lupin embryos with molecular masses of 73, 43 and 28 kDa, respectively. The temporal pattern of dehydrin protein accumulation correlates well with seed desiccation.     

Adjoint systems for models of cell signaling pathways and their application to parameter fitting

The paper concerns the problem of fitting mathematical models of cell signaling pathways. Such models frequently take the form of sets of nonlinear ordinary differential equations. While the model is continuous in time, the performance index used in the fitting procedure involves measurements taken at discrete time moments. Adjoint sensitivity analysis is a tool which can be used for finding the gradient of a performance index in the space of parameters of the model. In the paper, a structural formulation of adjoint sensitivity analysis called the generalized backpropagation through time (GBPTT) is used. The method is especially suited for hybrid, continuous-discrete time systems. As an example, we use the mathematical model NF-kappaB of the regulatory module, which plays a major role in the innate immune response in animals.     

The influence of modifications in imide fragment structure on 5-HT(1A) and 5-HT(7) receptor affinity and in vivo pharmacological properties of some new 1-(m-trifluoromethylphenyl)piperazines

New, flexible (7, 9, 11 and 13) and rigid (8, 10, 12 and 14) imides with a 1-(m-trifluorophenyl)piperazine fragment and a tetramethylene or a 1e,4e-cyclohexylene spacer, respectively, showed very high affinity (K(i)=0.3-34 nM) and agonistic in vivo activity for 5-HT(1A) receptors. Flexible new compounds and the previously described 5 also bound to 5-HT(7) receptors (K(i)=21-134 nM). Selected glutarimide derivatives, that is, the most potent postsynaptic 5-HT(1A) receptor agonist rigid compound 8 and its flexible analogue 7, as well as the previously described full agonist-rigid compound 6 and the partial agonist-its flexible counterpart 5 exhibited moderate affinity for alpha(1)-adrenoceptors (K(i)=85 - 268 nM), but were practically devoid of any affinity for dopamine D(2) sites. Those glutarimides demonstrated anxiolytic- (5 and 7) and antidepressant-like (5, 6 and 8) activity in the four-plate and the swim tests in mice, respectively; at the same time, however, they inhibited the locomotor activity of mice. The antidepressant-like effect of 8 was significantly stronger than that induced by imipramine used as a reference antidepressant.     

Statistical distribution of amino acid sequences: a proof of Darwinian evolution

MOTIVATION: The article presents results of the listing of the quantity of amino acids, dipeptides and tripeptides for all proteins available in the UNIPROT-TREMBL database and the listing for selected species and enzymes. UNIPROT-TREMBL contains protein sequences associated with computationally generated annotations and large-scale functional characterization. Due to the distinct metabolic pathways of amino acid syntheses and their physicochemical properties, the quantities of subpeptides in proteins vary. We have proved that the distribution of amino acids, dipeptides and tripeptides is statistical which confirms that the evolutionary biodiversity development model is subject to the theory of independent events. It seems interesting that certain short peptide combinations occur relatively rarely or even not at all. First, it confirms the Darwinian theory of evolution and second, it opens up opportunities for designing pharmaceuticals among rarely represented short peptide combinations. Furthermore, an innovative approach to the mass analysis of bioinformatic data is presented. CONTACT: eitner@amu.edu.pl SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.     

Clinical characteristics of tumors derived from colorectal cancer patients who harbor the Tumor Necrosis Factor α-1031T/T and NOD2 3020insC polymorphism

Background: Genetic predispositions to disease have focused on highly penetrant causative changes in tumor suppressor genes or genes associated with DNA mismatch repair. New investigations are revealing new genetic associations with disease that are more subtle in their association with disease and require characterization. Methods: In this report we have examined the tumor characteristics in a group of patients who have been shown to harbor two polymorphisms in two genes that are associated with the immune system NOD2 and TNFα. Results: Colorectal cancers from patients with NOD2 3020insC and TNFα-1031T/T constitutional changes are mostly right-sided disease (OR = 2.21, p = 0.03) with a tendency to higher stages (OR = 2.41, p = 0.06), increased number of associated polyps (OR = 1.77, p = 0.16) and later age of average age of disease onset (p = 0.039). Conclusion: The results reveal that there appear to be specific characteristics associated with the tumors that may aid in determining management strategies to reduce the risk of disease.     

ABCA1 is required for normal central nervous system ApoE levels and for lipidation of astrocyte-secreted apoE

ABCA1 is an ATP-binding cassette protein that transports cellular cholesterol and phospholipids onto high density lipoproteins (HDL) in plasma. Lack of ABCA1 in humans and mice causes abnormal lipidation and increased catabolism of HDL, resulting in very low plasma apoA-I, apoA-II, and HDL. Herein, we have used Abca1-/- mice to ask whether ABCA1 is involved in lipidation of HDL in the central nervous system (CNS). ApoE is the most abundant CNS apolipoprotein and is present in HDL-like lipoproteins in CSF. We found that Abca1-/- mice have greatly decreased apoE levels in both the cortex (80% reduction) and the CSF (98% reduction). CSF from Abca1-/- mice had significantly reduced cholesterol as well as small apoE-containing lipoproteins, suggesting abnormal lipidation of apoE. Astrocytes, the primary producer of CNS apoE, were cultured from Abca1+/+, +/-, and -/- mice, and nascent lipoprotein particles were collected. Abca1-/- astrocytes secreted lipoprotein particles that had markedly decreased cholesterol and apoE and had smaller apoE-containing particles than particles from Abca1+/+ astrocytes. These findings demonstrate that ABCA1 plays a critical role in CNS apoE metabolism. Since apoE isoforms and levels strongly influence Alzheimer's disease pathology and risk, these data suggest that ABCA1 may be a novel therapeutic target.