68 research outputs found

    Unmanned Aerial Vehicle: tecnologie e prospettive future

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    Partendo dalla definizione di UAV e UAS, arrivando a quella di drone, nella tesi saranno definiti i termini precedenti, ossia un sistema aereo senza pilota a bordo, la nascita del termine drone e le tendenze attuali. Dopo una precisa classificazione nelle quattro categorie principali (droni per hobbisti, commerciali e militari di me- dia grandezza, militari specifici di grandi dimensioni e stealth da combattimento) saranno descritti gli ambiti di utilizzo: da un lato quello militare e della sicurezza, dall’altro quello civile e scientifico. I capitoli centrali della tesi saranno il cuore dell’opera: l’architettura dell’UAV sarà descritta analizzando la totalità delle sue componenti, sia hardware che software. Verranno, quindi, analizzati i problemi relativi alla sicurezza, focalizzandosi sull’hacking di un UAV, illustrandone le varie tecniche e contromisure (tra cui anche come nascondersi da un drone). Il lavoro della tesi prosegue nei capitoli successivi con un’attenta trattazione della normativa vigente e dell’etica dei droni (nonché del diritto ad uccidere con tali sistemi). Il capitolo relativo alla tecnologia stealth sarà importante per capire le modalità di occultamento, le tendenze attuali e i possibili sviluppi futuri degli UAV militari da combattimento. Il capitolo finale sugli sviluppi futuri esporrà le migliorie tecnologiche e gli obiettivi degli UAV negli anni a venire, insieme ad eventuali utilizzi sia militari che civili. La ricerca sarà orientata verso sistemi miniaturizzati, multiple UAV e swarming

    Ladarixin, a dual CXCR1/2 inhibitor, attenuates experimental melanomas harboring different molecular defects by affecting malignant cells and tumor microenvironment.

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    CXCR1 and CXCR2 chemokine receptors and their ligands (CXCL1/2/3/7/8) play an important role in tumor progression. Tested to date CXCR1/2 antagonists and chemokine-targeted antibodies were reported to affect malignant cells in vitro and in animal models. Yet, redundancy of chemotactic signals and toxicity hinder further clinical development of these approaches. In this pre-clinical study we investigated the capacity of a novel small molecule dual CXCR1/2 inhibitor, Ladarixin (LDX), to attenuate progression of experimental human melanomas. Our data showed that LDX-mediated inhibition of CXCR1/2 abrogated motility and induced apoptosis in cultured cutaneous and uveal melanoma cells and xenografts independently of the molecular defects associated with the malignant phenotype. These effects were mediated by the inhibition of AKT and NF-kB signaling pathways. Moreover, systemic treatment of melanoma-bearing mice with LDX also polarized intratumoral macrophages to M1 phenotype, abrogated intratumoral de novo angiogenesis and inhibited melanoma self-renewal. Collectively, these studies outlined the pre-requisites of the successful CXCR1/2 inhibition on malignant cells and demonstrated multifactorial effects of Ladarixin on cutaneous and uveal melanomas, suggesting therapeutic utility of LDX in treatment of various melanoma types

    CXCR1/2 pathways in paclitaxel-induced neuropathic pain

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    Chemotherapy-induced peripheral neuropathy (CIPN) is a type of neuropathic pain that represents a frequent and serious consequence of chemotherapy agents. Over the last years, significant progress has been achieved in elucidating the underlying pathogenesis of CIPN. The interference of taxanes with microtubule has been proposed as a mechanism that leads to altered axonal transport and to permanent neurological damages. The inflammatory process activated by chemotherapeutic agents has been considered as a potential trigger of nociceptive process in CIPN.In this study we investigated the effect of reparixin, an inhibitor of CXCR1/CXCR2, in suppressing the development of paclitaxel-induced nociception in rats. Moreover, reparixin activity in reversing the neurotoxic effects induced by paclitaxel or GRO/KC in F11 cells was also analyzed.Reparixin administered by continuous infusion ameliorated paclitaxel-induced mechanical and cold allodynia in rats. In F11 cells, reparixin was able to inhibit the increase of acetyladed α-tubulin induced both by paclitaxel and GRO/KC. The subsequent experiments were performed in order to dissect the signal transduction pathways under GRO/KC control, eventually modulated by paclitaxel and/or reparixin. To this aim we found that reparixin significantly counteracted p-FAK, p-JAK2/p-STAT3, and PI3K-p-cortactin activation induced either by paclitaxel or GRO/KC.Overall the present results have identified IL-8/CXCR1/2 pathway as a mechanism involved in paclitaxel-induced peripheral neuropathy. In particular, the obtained data suggest that the inhibition of CXCR1/2 combined with standard taxane therapy, in addition to potentiating the taxane anti-tumor activity can reduce chemotherapy-induced neurotoxicity, thus giving some insight for the development of novel treatments

    Inflammation-Independent Antinociceptive Effects of DF2755A, a CXCR1/2 Selective Inhibitor: A New Potential Therapeutic Treatment for Peripheral Neuropathy Associated to Non-Ulcerative Interstitial Cystitis/Bladder Pain Syndrome

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    Interstitial cystitis (IC)/bladder pain syndrome (BPS) is a chronic bladder disease of unknown etiology characterized by urinary frequency and episodic and chronic pain. Analgesic treatments for IC/BPS are limited, especially for patients with non-Hunner (non-ulcerative) type IC who usually have poor overall outcomes. Here, we demonstrate that oral treatment with DF2755A, a potent and selective inhibitor of chemokine receptors CXCR1/2, can prevent and reverse peripheral neuropathy associated to non-Hunner IC/BPS by directly inhibiting chemokine-induced excitation of sensory neurons. We tested DF2755A antinociceptive effects in a cyclophosphamide (CYP)-induced non-ulcerative IC rat model characterized by severe peripheral neuropathy in the absence of bladder inflammatory infiltrate, urothelial hyperplasia, and hemorrhage. Treatment with DF2755A prevented the onset of peripheral neuropathy and reversed its development in CYP-induced IC rats, showing a strong and long-lasting anti-hyperalgesic effect. Ex vivo and in vitro studies showed that DF2755A treatment strongly inhibited the expression of CXCR2 agonists, CXCL1/KC, and CXCL5 and of transient receptor potential vanilloid 1 (TRPV1) compared to vehicle, suggesting that its effects can be due to the inhibition of the nociceptive signaling passing through the CXCL1/CXCR1-2 axis and TRPV1. In conclusion, our results highlight the key pathophysiological role played by the CXCL1/CXCR1-2 axis and TRPV1 in the onset and development of peripheral neuropathy in non-Hunner IC and propose DF2755A as a potential therapeutic approach for the treatment of not only inflammatory painful conditions but also neuropathic ones and in particular non-Hunner IC/BPS

    Adsorption of the rhNGF Protein on Polypropylene with Different Grades of Copolymerization

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    The surface properties of drug containers should reduce the adsorption of the drug and avoid packaging surface/drug interactions, especially in the case of biologically-derived products. Here, we developed a multi-technique approach that combined Differential Scanning Calorimetry (DSC), Atomic Force Microscopy (AFM), Contact Angle (CA), Quartz Crystal Microbalance with Dissipation monitoring (QCM-D), and X-ray Photoemission Spectroscopy (XPS) to investigate the interactions of rhNGF on different pharma grade polymeric materials. Polypropylene (PP)/polyethylene (PE) copolymers and PP homopolymers, both as spin-coated films and injected molded samples, were evaluated for their degree of crystallinity and adsorption of protein. Our analyses showed that copolymers are characterized by a lower degree of crystallinity and lower roughness compared to PP homopolymers. In line with this, PP/PE copolymers also show higher contact angle values, indicating a lower surface wettability for the rhNGF solution on copolymers than PP homopolymers. Thus, we demonstrated that the chemical composition of the polymeric material and, in turn, its surface roughness determine the interaction with the protein and identified that copolymers may offer an advantage in terms of protein interaction/adsorption. The combined QCM-D and XPS data indicated that protein adsorption is a self-limiting process that passivates the surface after the deposition of roughly one molecular layer, preventing any further protein adsorption in the long term

    A Multicenter Phase 2 Randomized Controlled Study on the Efficacy and Safety of Reparixin in the Treatment of Hospitalized Patients with COVID-19 Pneumonia

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    Introduction Acute lung injury and acute respiratory distress syndrome are common complications in patients with coronavirus disease 2019 (COVID-19). Poor outcomes in patients with COVID-19 are associated with cytokine release syndrome. Binding of interleukin-8 (CXCL8/IL-8) to its chemokine receptors, CXCR1/2, may mediate this inflammatory process. The aim of this clinical trial was to determine if CXCR1/2 blockade with reparixin can improve clinical outcomes in hospitalized patients with severe COVID-19 pneumonia. The dose and safety of reparixin have been investigated in clinical trials of patients with metastatic breast cancer. Methods This was a phase 2, open-label, multicenter, randomized study in hospitalized adult patients with severe COVID-19 pneumonia from May 5, 2020 until November 27, 2020. Patients were randomized 2:1 to receive 1200 mg reparixin orally three times daily or standard of care (SOC) for up to 21 days. The primary endpoint was defined as a composite of clinical events: use of supplemental oxygen, need for mechanical ventilation, intensive care unit admission, and/or use of rescue medication. Results Fifty-five patients were enrolled between reparixin (n = 36) and SOC (n = 19). The rate of clinical events was statistically significantly lower in the reparixin group compared with the SOC group (16.7% [95% CI 6.4-32.8%] vs. 42.1% [95% CI 20.3-66.5%], P = 0.02). The sensitivity analysis based on the Cox regression model provided an adjusted hazard ratio of 0.33 with statistical significance lower than 0.05 (95% CI 0.11-0.99; P = 0.047). Reparixin treatment appeared to be well tolerated. Conclusion In patients with severe COVID-19, reparixin led to an improvement in clinical outcomes when compared with the SOC. A larger phase 3 clinical study is needed to confirm these results

    CXCL1-CXCR1/2 signaling is induced in human temporal lobe epilepsy and contributes to seizures in a murine model of acquired epilepsy

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    Abstract CXCL1, a functional murine orthologue of the human chemokine CXCL8 (IL-8), and its CXCR1 and CXCR2 receptors were investigated in a murine model of acquired epilepsy developing following status epilepticus (SE) induced by intra-amygdala kainate. CXCL8 and its receptors were also studied in human temporal lobe epilepsy (TLE). The functional involvement of the chemokine in seizure generation and neuronal cell loss was assessed in mice using reparixin (formerly referred to as repertaxin), a non-competitive allosteric inhibitor of CXCR1/2 receptors. We found a significant increase in hippocampal CXCL1 level within 24 h of SE onset that lasted for at least 1 week. No changes were measured in blood. In analogy with human TLE, immunohistochemistry in epileptic mice showed that CXCL1 and its two receptors were increased in hippocampal neuronal cells. Additional expression of these molecules was found in glia in human TLE. Mice were treated with reparixin or vehicle during SE and for additional 6 days thereafter, using subcutaneous osmotic minipumps. Drug-treated mice showed a faster SE decay, a reduced incidence of acute symptomatic seizures during 48 h post-SE, and a delayed time to spontaneous seizures onset compared to vehicle controls. Upon reparixin discontinuation, mice developed spontaneous seizures similar to vehicle mice, as shown by EEG monitoring at 14 days and 2.5 months post-SE. In the same epileptic mice, reparixin reduced neuronal cell loss in the hippocampus vs vehicle-injected mice, as assessed by Nissl staining at completion of EEG monitoring. Reparixin administration for 2 weeks in mice with established chronic seizures, reduced by 2-fold on average seizure number vs pre-treatment baseline, and this effect was reversible upon drug discontinuation. No significant changes in seizure number were measured in vehicle-injected epileptic mice that were EEG monitored in parallel. Data show that CXCL1-IL-8 signaling is activated in experimental and human epilepsy and contributes to acute and chronic seizures in mice, therefore representing a potential new target to attain anti-ictogenic effects

    DHFR Inhibitors Display a Pleiotropic Anti-Viral Activity against SARS-CoV-2: Insights into the Mechanisms of Action

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    During the COVID-19 pandemic, drug repurposing represented an effective strategy to obtain quick answers to medical emergencies. Based on previous data on methotrexate (MTX), we evaluated the anti-viral activity of several DHFR inhibitors in two cell lines. We observed that this class of compounds showed a significant influence on the virus-induced cytopathic effect (CPE) partly attributed to the intrinsic anti-metabolic activity of these drugs, but also to a specific anti-viral function. To elucidate the molecular mechanisms, we took advantage of our EXSCALATE platform for in-silico molecular modelling and further validated the influence of these inhibitors on nsp13 and viral entry. Interestingly, pralatrexate and trimetrexate showed superior effects in counteracting the viral infection compared to other DHFR inhibitors. Our results indicate that their higher activity is due to their polypharmacological and pleiotropic profile. These compounds can thus potentially give a clinical advantage in the management of SARS-CoV-2 infection in patients already treated with this class of drugs

    The role of extracellular vesicles and interleukin-8 in regulating and mediating neutrophil-dependent cancer drug resistance

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    Tumor drug resistance is a multifactorial and heterogenous condition that poses a serious burden in clinical oncology. Given the increasing incidence of resistant tumors, further understanding of the mechanisms that make tumor cells able to escape anticancer drug effects is pivotal for developing new effective treatments. Neutrophils constitute a considerable proportion of tumor infiltrated immune cells, and studies have linked elevated neutrophil counts with poor prognosis. Tumor-associated neutrophils (TANs) can acquire in fact immunoregulatory capabilities, thus regulating tumor progression and resistance, or response to therapy. In this review, we will describe TANs’ actions in the tumor microenvironment, with emphasis on the analysis of the role of interleukin-8 (IL-8) and extracellular vesicles (EVs) as crucial modulators and mediators of TANs biology and function in tumors. We will then discuss the main mechanisms through which TANs can induce drug resistance, finally reporting emerging therapeutic approaches that target these mechanisms and can thus be potentially used to reduce or overcome neutrophil-mediated tumor drug resistance

    Phase 2 randomized, double-masked, vehicle-controlled trial of recombinant human nerve growth factor for neurotrophic keratitis

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    Purpose: To evaluate the safety and efficacy of topical recombinant human nerve growth factor (rhNGF) for treating moderate-to-severe neurotrophic keratitis (NK), a rare degenerative corneal disease resulting from impaired corneal innervation. Design: Phase 2 multicenter, randomized, double-masked, vehicle-controlled trial. Participants: Patients with stage 2 (moderate) or stage 3 (severe) NK in 1 eye. Methods: The REPARO phase 2 study assessed safety and efficacy in 156 patients randomized 1:1:1 to rhNGF 10 μg/ml, 20 μg/ml, or vehicle. Treatment was administered 6 drops per day for 8 weeks. Patients then entered a 48- or 56-week follow-up period. Safety was assessed in all patients who received study treatment, whereas efficacy was by intention to treat. Main Outcome Measures: Corneal healing (defined as <0.5-mm maximum diameter of fluorescein staining in the lesion area) was assessed by masked central readers at week 4 (primary efficacy end point) and week 8 (key secondary end point) of controlled treatment. Corneal healing was reassessed post hoc by masked central readers using a more conservative measure (0-mm staining in the lesion area and no other persistent staining). Results: At week 4 (primary end point), 19.6% of vehicle-treated patients achieved corneal healing (<0.5-mm lesion staining) versus 54.9% receiving rhNGF 10 μg/ml (+35.3%; 97.06% confidence interval [CI], 15.88–54.71; P < 0.001) and 58.0% receiving rhNGF 20 μg/ml (+38.4%; 97.06% CI, 18.96–57.83; P < 0.001). At week 8 (key secondary end point), 43.1% of vehicle-treated patients achieved less than 0.5-mm lesion staining versus 74.5% receiving rhNGF 10 μg/ml (+31.4%; 97.06% CI, 11.25–51.49; P = 0.001) and 74.0% receiving rhNGF 20 μg/ml (+30.9%; 97.06% CI, 10.60–51.13; P = 0.002). Post hoc analysis of corneal healing by the more conservative measure (0-mm lesion staining and no other persistent staining) maintained statistically significant differences between rhNGF and vehicle at weeks 4 and 8. More than 96% of patients who healed after controlled rhNGF treatment remained recurrence free during follow-up. Treatment with rhNGF was well tolerated; adverse effects were mostly local, mild, and transient. Conclusions: Topical rhNGF is safe and more effective than vehicle in promoting healing of moderate-to-severe NK
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