8,932 research outputs found
Oral health of elite athletes and association with performance: a systematic review.
We aimed to systematically review the epidemiology of oral disease and trauma in the elite athlete population and to investigate the impact of oral health on sporting performance
Spectrally resolved observations of atmospheric emitted radiance in the H2O rotation band
This paper presents the project Earth Cooling by Water
Vapor Radiation, an observational programme, which aims at
developing a database of spectrally resolved far infrared
observations, in atmospheric dry conditions, in order to
validate radiative transfer models and test the quality of water
vapor continuum and line parameters. The project provides
the very first set of far-infrared spectral downwelling
radiance measurements, in dry atmospheric conditions,
which are complemented with Raman Lidar-derived
temperature and water vapor profiles
An extracellular transglutaminase is required for apple pollen tube growth
An extracellular form of the calcium-dependent protein-crosslinking enzyme TGase (transglutaminase) was demonstrated to be involved in the apical growth of Malus domestica pollen tube. Apple pollen TGase and its substrates were co-localized within aggregates on the pollen tube surface, as determined by indirect immunofluorescence staining and the in situ cross-linking of fluorescently labelled substrates. TGase-specific inhibitors and an anti-TGase monoclonal antibody blocked pollen tube growth, whereas incorporation of a recombinant fluorescent mammalian TGase substrate (histidine-tagged green fluorescent protein:His6– Xpr–GFP) into the growing tube wall enhanced tube length and germination, consistent with a role of TGase as a modulator of cell wall building and strengthening. The secreted pollen TGase catalysed the cross-linking of both PAs (polyamines) into proteins (released by the pollen tube) and His6-Xpr-GFP into endogenous or exogenously added substrates. A similar distribution of TGase activitywas observed in planta on pollen tubes germinating inside the style, consistent with a possible additional role for TGase in the interaction between the pollen tube and the style during fertilization
Eligible strategies of drought response to improve drought resistance in woody crops: a mini-review
Drought is the main abiotic stress that negatively affects the crop yield. Due to the rapid climate change, actual plant defence mechanisms may be less effective against increased drought stress and other related or co-occurring abiotic stresses such as salt and high temperature. Thus, genetic engineering approaches may be an important tool for improving drought tolerance in crops. This mini-review focuses on the responses to drought stress of the woody crop species Olea europaea and Citrus sp., selecting in particular five main strategies adopted by plants in response to drought stress: aquaporin (AQPs) expression, antioxidant activity, ABA signalling, and trehalose and proline accumulation. Transgenic studies on both the herbaceous Arabidopsis and woody Populus plant models showed an improvement in drought resistance with increasing expression of these drought-inducible genes. Outcomes from the present study suggest the overexpression of the gene families associated with AQPs and ABA biosynthesis, mainly involved in regulating water transport and in preventing water loss, respectively, as candidate targets for improving drought resistance; antioxidants-, trehalose- and proline-related genes remain valid candidates for resistance to a wider spectrum of abiotic stressors, including drought. However, the contribution of an increased stiffness of the modulus elasticity of leaf parenchyma cell walls to the rapid recovery of leaf water potential, delaying by this way the stress onset, is not a secondary aspect of the transgenic optimization, in particular for Olea cultivars
Pleiotropic antitumor effects of the pan-HDAC inhibitor ITF2357 against c-Myc-overexpressing human B-cell non-Hodgkin lymphomas,
Histone deacetylases (HDAC) extensively contribute to the c-Myc oncogenic program, pointing to their inhibition as an effective strategy against c-Myc-overexpressing cancers. We, thus, studied the therapeutic activity of the new-generation pan-HDAC inhibitor ITF2357 (Givinostat®) against c-Myc-overexpressing human B-cell non-Hodgkin lymphomas (B-NHLs). ITF2357 anti-proliferative and pro-apoptotic effects were analyzed in B-NHL cell lines with c-Myc translocations (Namalwa, Raji and DOHH-2), stabilizing mutations (Raji) or post-transcriptional alterations (SU-DHL-4) in relationship to c-Myc modulation. ITF2357 significantly delayed the in vitro growth of all B-NHL cell lines by inducing G1 cell-cycle arrest, eventually followed by cell death. These events correlated with the extent of c-Myc protein, but not mRNA, downregulation, indicating the involvement of post-transcriptional mechanisms. Accordingly, c-Myc-targeting microRNAs let-7a and miR-26a were induced in all treated lymphomas and the cap-dependent translation machinery components 4E-BP1, eIF4E and eIF4G, as well as their upstream regulators, Akt and PIM kinases, were inhibited in function of the cell sensitivity to ITF2357, and, in turn, c-Myc downregulation. In vivo, ITF2357 significantly hampered the growth of Namalwa and Raji xenografts in immunodeficient mice. Noteworthy, its combination with suboptimal cyclophosphamide, achieved complete remissions in most animals and equaled or even exceeded the activity of optimal cyclophosphamide. Collectively, our findings provide the rationale for testing the clinical advantages of adding ITF2357 to current therapies for the still very ominous c-Myc-overexpressing lymphomas. They equally provide the proof-of-concept for its clinical evaluation in rational combination with the promising inhibitors of B-cell receptor and PI3K/Akt/mTOR axis currently in the process of development
Geometry of unitary orbits of pinching operators
Let I be a symmetrically-normed ideal of the space of bounded operators acting on a Hilbert space H. Let {pi}1w(1≤w≤∞) be a family of mutually orthogonal projections on H. The pinching operator associated with the former family of projections is given by P:I→I,P(x)=∑i=1wpixpi. Let UI denote the Banach-Lie group of the unitary operators whose difference with the identity belongs to I. We study geometric properties of the orbit UI(P)={LuPLu*:u∈UI}, where Lu is the left representation of UI on the algebra B(I) of bounded operators acting on I. The results include necessary and sufficient conditions for UI(P) to be a submanifold of B(I). Special features arise in the case of the ideal K of compact operators. In general, UK(P) turns out to be a non complemented submanifold of B(K). We find a necessary and sufficient condition for UK(P) to have complemented tangent spaces in B(K). We also show that UI(P) is a covering space of another orbit of pinching operators.Facultad de Ciencias Exacta
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