Nonlinear optical processes at soft x-ray wavelengths have remained largely unexplored due to the lack of available light sources with the requisite intensity and coherence. Here we report the ...observation of soft x-ray second harmonic generation near the carbon K edge (∼284 eV) in graphite thin films generated by high intensity, coherent soft x-ray pulses at the FERMI free electron laser. Our experimental results and accompanying first-principles theoretical analysis highlight the effect of resonant enhancement above the carbon K edge and show the technique to be interfacially sensitive in a centrosymmetric sample with second harmonic intensity arising primarily from the first atomic layer at the open surface. This technique and the associated theoretical framework demonstrate the ability to selectively probe interfaces, including those that are buried, with elemental specificity, providing a new tool for a range of scientific problems.
Poly(ADP-ribose) polymerase (PARP) inhibitors represent a promising strategy toward the treatment of triple-negative breast cancer (TNBC), which is often associated to genomic instability and/or BRCA ...mutations. However, clinical outcome is controversial and no benefits have been demonstrated in wild type BRCA cancers, possibly due to poor drug bioavailability and low nuclear delivery. In the attempt to overcome these limitations, we have developed H-Ferritin nanoformulated olaparib (HOla) and assessed its anticancer efficacy on both BRCA-mutated and non-mutated TNBC cells. We exploited the natural tumor targeting of H-Ferritin, which is mediated by the transferrin receptor-1 (TfR1), and its physiological tropism toward cell nucleus. TNBC cell lines over-expressing TfR-1 were successfully recognized by H-Ferritin, displaying a fast internalization into the cells. HOla induced remarkable cytotoxic effect in cancer cells, exhibiting 1000-fold higher anticancer activity compared to free olaparib (Ola). Accordingly, HOla treatment enhanced PARP-1 cleavage, DNA double strand breaks and Ola delivery into the nuclear compartment. Our findings suggest that H-Ferritin nanoformulation strongly enhances cytotoxic efficacy of Ola as a stand-alone therapy in both BRCA-mutated and wild type TNBC cells, by promoting targeted nuclear delivery.
DS Tuc Ab is a Neptune-sized planet that orbits around a G star in the 45 Myr old Tucana-Horologium moving group. Here, we report the measurement of the sky-projected angle between the stellar spin ...axis and the planet's orbital axis, based on the observation of the Rossiter-McLaughlin effect during three separate planetary transits. The orbit appears to be well aligned with the equator of the host star, with a projected obliquity of . In addition to the distortions in the stellar absorption lines due to the transiting planet, we observed variations that we attribute to large starspots, with angular sizes of tens of degrees. The technique that we have developed for simultaneous modeling of starspots and the planet-induced distortions may be useful in other observations of planets around active stars.
Saliva collection is considered a non-invasive method to detect inflammatory markers in response to emotional states within natural social contexts. Numerous studies have prompted an important role ...of cytokines in modulating distinct aspects of social and emotional behavior. The aim of this study was to investigate the reliability of plasma and saliva as investigative tools for measure some inflammatory marker levels (CRP, IL-1β, IL-18, and IL-6). At the same time, the relationships between these markers and emotional states in response to a socio-cognitive stress (Academic Exam, AE), were considered. It was demonstrated that the plasma and saliva concentrations of all immune-mediators analyzed were significantly related across the socio-cognitive stress. In addition, when there was a close correlation to AE, the anger state, the IL-1β, the IL-18 salivary and plasmatic concentrations were significantly higher, while they decreased during the AE. On the other hand, the anxiety state and the IL-6 levels significantly increased throughout the AE. The IL-1β and IL-6 were positively associated to the anger and the anxiety state, respectively. In conclusion, our data highlight that different immune markers are similarly detectable in plasma and saliva during socio-cognitive stress. Also, they could be related to different emotional responses.
The delivery of therapeutics across the cell membrane and into the cytoplasm is a major challenge that limits the development of new therapies. This challenge is compounded by the lack of a general ...assay for cytosolic delivery. Here we develop this assay based on the pro-fluorophore CrAsH-EDT2, and provide cytosolic penetration results for a variety of drug delivery agents (polyethyleneimine, poly-arginine, Ferritin, poly maleic anhydride-alt-isobutene grafted with dodecylamine, and cationic liposomes) into HeLa and T98G cells. Our results show that this method can be widely applicable to different cells and drug delivery agents, and yield statistically robust results. We later use this method to optimize and improve a model drug delivery agent's (Ferritin) cytosolic penetration.
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In this study we have generated a EYFP targeted to the mitochondrial intermembrane space (MIMS-EYFP) to determine for the first time the pH within this compartment. The fragment encoding HAI-tagged ...EYFP was fused with the C-terminus of glycerol-phosphate dehydrogenase, an integral protein of the inner mitochondrial membrane. Human ECV304 cells transiently transfected with MIMS-EYFP showed the typical mitochondrial network, co-localized with MitoTracker Red. Following the calibration procedure, an estimation of the pH value in the intermembrane space was obtained. This value (6.88
±
0.09) was significantly lower than that determined in the cytosol after transfection with a cytosolic EYFP (7.59
±
0.01). Further, the pH of the mitochondrial matrix, determined with a EYFP targeted to this subcompartment, was 0.9 pH units higher than that in the intermembrane space. In conclusion, MIMS-EYFP represents a novel powerful tool to monitor pH changes in the mitochondrial intermembrane space of live cells.
Mitochondrial dynamics and Ca2+ signaling Szabadkai, G; Simoni, A M; Bianchi, K ...
Biochimica et biophysica acta,
2006 May-Jun, 2006-05-00, Letnik:
1763, Številka:
5-6
Journal Article
Recenzirano
Odprti dostop
Recent data shed light on two novel aspects of the mitochondria-Ca2+ liaison. First, it was extensively investigated how Ca2+ handling is controlled by mitochondrial shape, and positioning; a ...playground also of cell death and survival regulation. On the other hand, significant progress has been made to explore how intra- and near-mitochondrial Ca2+ signals modify mitochondrial morphology and cellular distribution. Here, we shortly summarize these advances and provide a model of Ca2+-mitochondria interactions.
The efficient targeting of cancer cells depends on the success of obtaining the active targeting of overexpressed receptors. A very accurate design of nanoconjugates should be done
via
the selection ...of the conjugation strategy to achieve effective targeted nanoconjugates. Here, we present a detailed study of cetuximab-conjugated nonspherical gold nanocages for the active targeting of triple-negative breast cancer cells, including MDA-MB-231 and MDA-MB-468. A few different general strategies were selected for monoclonal antibody conjugation to the nanoparticle surface. By varying the bioconjugation conditions, including antibody orientation or the presence of a polymeric spacer or recombinant protein biolinker, we demonstrate the importance of a rational design of nanoconjugates. A quantitative study of gold content
via
ICP-AES allowed us to compare the effectiveness of cellular uptake as a function of the conjugation strategy and confirmed the active nature of nanoparticle internalization in cancer cells
via
epidermal growth factor receptor recognition, corroborating the importance of the rational design of nanomaterials for nanomedicine.
The efficient targeting of cancer cells depends on the success of obtaining the active targeting of overexpressed receptors.
•Oxidative metabolism is associated with executive functions.•PBMCs superoxide anion production is negatively related to executive functions.•Peripheral GPx and CAT enzymatic activities are ...correlated to executive functions.
Executive Functions (EFs) involve a set of high cognitive abilities impairment which have been successfully related to a redox omeostasis imbalance in several psychiatric disorders. Firstly, we aimed to investigate the relationship between executive functioning and some oxidative metabolism parameters in Peripheral Blood Mononuclear Cells (PBMCs) from healthy adult samples. The Brown Attention-Deficit Disorder Scales were administered to assess five specific facets of executive functioning. Total superoxide anion production, Super Oxide Dismutase (SOD), Catalase (CAT), Glutathione Reductase (GR) and Glutathione Peroxidase (GPx) activities were evaluated on proteins extracted from the PBMCs. We found significant positive correlations between superoxide anion production and the total score of the ‘Brown’ Scale and some of its clusters. The GPx and CAT activities were negatively associated with the total score and some clusters. In a linear regression analysis, these biological variables were indicated as the most salient predictors of the total score, explaining the 24% variance (adjusted R(2)=0.24, ANOVA, p<.001). This study provides novel evidence that Executive Functions have underpinnings in the oxidative metabolism, as ascertained in healthy subjects.
Abstract
The Taurus-Auriga complex is the prototypical low-mass star-forming region, and provides a unique testbed of the star formation process, which left observable imprints on the spatial, ...kinematic, and temporal structure of its stellar population. Taurus’s rich observational history has uncovered peculiarities that suggest a complicated star-forming event, such as members at large distances from the molecular clouds and evidence of an age spread. With Gaia, an in-depth study of the Taurus census is possible, to confirm membership, identify substructure, and reconstruct its star formation history. We have compiled an expansive census of the greater Taurus region, identifying spatial subgroups and confirming that Taurus is substructured across stellar density. There are two populations of subgroups: clustered groups near the clouds and sparse groups spread throughout the region. The sparse groups comprise Taurus’s distributed population, which is on average older than the population near the clouds, and hosts subpopulations up to 15 Myr old. The ages of the clustered groups increase with distance, suggesting that the current star formation was triggered from behind. Still, the region is kinematically coherent, and its velocity structure reflects an initial turbulent spectrum similar to Larson’s Law that has been modified by dynamical relaxation. Overall, Taurus has a complicated star formation history, with at least two epochs of star formation featuring both clustered and distributed modes. Given the correlations between age and spatial distribution, Taurus might be part of a galaxy-scale star-forming event that can only begin to be understood in the Gaia era.