76 research outputs found

    Fragmentation reactions of thiourea- and urea-compounds examined by tandem MS-, energy-resolved CID experiments, and theory

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    pre-printFragmentation reactions of thiourea- and urea-compounds, which are promising reagents for chemical crosslinking (XL), are investigated in detail by collision-induced dissociation (CID) experiments in a quadrupole ion trap (QIT), energy-resolved CID experiments, and computational modeling. For this study, an array of six labeled and unsymmetrical substituted thiourea- and urea-derivatives were synthesized, which allow unambiguous characterization of competing fragmentation pathways. The results of the QIT-CID-experiments are explored in detail for two compounds and confirmed by results for the other four. These results document the subtle competition of characteristic fragmentation pathways of this class of compounds. The multi dimensional investigations of the characteristic fragmentation reactions allow reliable structure proposals of prominent product ions. Energy-dependent CID experiments on two of the six compounds lead to breakdown curves that show similar relative threshold energies for the formation of the product ions on which the functioning of the XL application relies. The experimental results are in full consistency with the results from in-depth computations. For the dominant fragmentations observed, the transition states for moving the proton from the most basic site of the precursor ion (the thiourea-sulphur or the urea carbonyl oxygen) to less basic heteroatoms in the protonated molecular ion is the necessary and decisive step that determines the extent of the charge-driven fragmentation processes that follow

    Image-Based Monitoring of Cracks: Effectiveness Analysis of an Open-Source Machine Learning-Assisted Procedure

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    The proper inspection of a cracks pattern over time is a critical diagnosis step to provide a thorough knowledge of the health state of a structure. When monitoring cracks propagating on a planar surface, adopting a single-image-based approach is a more convenient (costly and logistically) solution compared to subjective operators-based solutions. Machine learning (ML)- based monitoring solutions offer the advantage of automation in crack detection; however, complex and time-consuming training must be carried out. This study presents a simple and automated ML-based crack monitoring approach implemented in open sources software that only requires a single image for training. The effectiveness of the approach is assessed conducting work in controlled and real case study sites. For both sites, the generated outputs are significant in terms of accuracy (~1 mm), repeatability (sub-mm) and precision (sub-pixel). The presented results highlight that the successful detection of cracks is achievable with only a straightforward ML-based training procedure conducted on only a single image of the multi-temporal sequence. Furthermore, the use of an innovative camera kit allowed exploiting automated acquisition and transmission fundamental for Internet of Things (IoTs) for structural health monitoring and to reduce user-based operations and increase safety

    Bone structural similarity score: a multiparametric tool to match properties of biomimetic bone substitutes with their target tissues

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    Background: One of the hardest tasks in developing or selecting grafts for bone substitution surgery or tissue engineering is to match the structural and mechanical properties of tissue at the recipient site, because of the large variability of tissue properties with anatomical site, sex, age and health conditions of the patient undergoing implantation. We investigated the feasibility of defining a quantitative bone structural similarity score based on differences in the structural properties of synthetic grafts and bone tissue. Methods: Two biocompatible hydroxyapatite porous scaffolds with different nominal pore sizes were compared with trabecular bone tissues from equine humerus and femur. Images of samples’ structures were acquired by high-resolution micro-computed tomography and analyzed to estimate porosity, pore size distribution and interconnectivity, specific surface area, connectivity density and degree of anisotropy. Young’s modulus and stress at break were measured by compression tests. Structural similarity distances between sample pairs were defined based on scaled and weighted differences of the measured properties. Their feasibility was investigated for scoring structural similarity between considered scaffolds or bone tissues. Results: Manhattan distances and Quadrance generally showed sound and consistent similarities between sample pairs, more clearly than simple statistical comparison and with discriminating capacity similar to image-based scores to assess progression of pathologies affecting bone structure. Conclusions: The results suggest that a quantitative and objective bone structural similarity score may be defined to help biomaterials scientists fabricate, and surgeons select, the graft or scaffold best mimicking the structure of a given bone tissue

    Protection of Prisoners with Mental Health Disorders in Italy: Lights and Shadows after the Abolition of Judicial Psychiatric Hospitals

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    In Italy, a person suffering from a mental disorder who commits a crime will be given a custodial security order and serve the period of admission at a Residenza per la esecuzione delle misure di sicurezza (REMS) (Residence for the Execution of Security Measures, hereinafter "REMS"). These institutions have been established recently and though equipped with the necessary safety measures, the focus is on psychiatric therapy. Despite being present on a national scale, access is very limited in terms of capacity. Immediate remedial measures are needed, so much so that the European Court of Human Rights recently condemned Italy for this very reason. This article, through a review of the constitutive principles of these institutions, shows how they have very positive aspects such as the attention to necessary psychotherapy in order to protect the right to health and the real taking charge of the fragility of the subjects; however, it is seen how there are many negative aspects linked above all to the scarce availability of places in these structures. The article provides suggestions on a more comprehensive strategy for facilities for detainees with mental disorders

    The metabolism of cells regulates their sensitivity to NK cells depending on p53 status

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    Leukemic cells proliferate faster than non-transformed counterparts. This requires them to change their metabolism to adapt to their high growth. This change can stress cells and facilitate recognition by immune cells such as cytotoxic lymphocytes, which express the activating receptor Natural Killer G2-D (NKG2D). The tumor suppressor gene p53 regulates cell metabolism, but its role in the expression of metabolism-induced ligands, and subsequent recognition by cytotoxic lymphocytes, is unknown. We show here that dichloroacetate (DCA), which induces oxidative phosphorylation (OXPHOS) in tumor cells, induces the expression of such ligands, e.g. MICA/B, ULBP1 and ICAM-I, by a wtp53-dependent mechanism. Mutant or null p53 have the opposite effect. Conversely, DCA sensitizes only wtp53-expressing cells to cytotoxic lymphocytes, i.e. cytotoxic T lymphocytes and NK cells. In xenograft in vivo models, DCA slows down the growth of tumors with low proliferation. Treatment with DCA, monoclonal antibodies and NK cells also decreased tumors with high proliferation. Treatment of patients with DCA, or a biosimilar drug, could be a clinical option to increase the effectiveness of CAR T cell or allogeneic NK cell therapies

    Rate and duration of hospitalisation for acute pulmonary embolism in the real-world clinical practice of different countries : Analysis from the RIETE registry

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    The management of acute venous thromboembolism in clinical practice. Results from the European PREFER in VTE Registry

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    Venous thromboembolism (VTE) is a significant cause of morbidity and mortality in Europe. Data from real-world registries are necessary, as clinical trials do not represent the full spectrum of VTE patients seen in clinical practice. We aimed to document the epidemiology, management and outcomes of VTE using data from a large, observational database. PREFER in VTE was an international, non-interventional disease registry conducted between January 2013 and July 2015 in primary and secondary care across seven European countries. Consecutive patients with acute VTE were documented and followed up over 12 months. PREFER in VTE included 3,455 patients with a mean age of 60.8 ± 17.0 years. Overall, 53.0 % were male. The majority of patients were assessed in the hospital setting as inpatients or outpatients (78.5 %). The diagnosis was deep-vein thrombosis (DVT) in 59.5 % and pulmonary embolism (PE) in 40.5 %. The most common comorbidities were the various types of cardiovascular disease (excluding hypertension; 45.5 %), hypertension (42.3 %) and dyslipidaemia (21.1 %). Following the index VTE, a large proportion of patients received initial therapy with heparin (73.2 %), almost half received a vitamin K antagonist (48.7 %) and nearly a quarter received a DOAC (24.5 %). Almost a quarter of all presentations were for recurrent VTE, with >80 % of previous episodes having occurred more than 12 months prior to baseline. In conclusion, PREFER in VTE has provided contemporary insights into VTE patients and their real-world management, including their baseline characteristics, risk factors, disease history, symptoms and signs, initial therapy and outcomes
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