1,517 research outputs found

    Synthesis of quinoxaline 1,4-di-N-oxide derivatives on solid support using room temperature and microwave-assisted solvent-free procedures

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    We describe the synthesis of 12 new ethyl and methyl quinoxaline-7-carboxylate 1,4-di-N-oxide derivatives on solid supports with room temperature and microwave-assisted solvent-free procedures. Results show that solid supports have good catalytic activity in the formation of quinoxaline 1,4-di-N-oxide derivatives. We found that florisil and montmorillonite KSF and K10 could be used as new, easily available, inexpensive alternatives of catalysts. Additionally, room temperature and microwave-irradiation solvent-free synthesis was more efficient than a conventional procedure (Beirut reaction), reducing reaction time and increasing yield

    Characterization of New TRPM8 Modulators in Pain Perception

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    Background: Transient Receptor Potential Melastatin-8 (TRPM8) is a non-selective cation channel activated by cold temperature and by cooling agents. Several studies have proved that this channel is involved in pain perception. Although some studies indicate that TRPM8 inhibition is necessary to reduce acute and chronic pain, it is also reported that TRPM8 activation produces analgesia. These conflicting results could be explained by extracellular Ca2+-dependent desensitization that is induced by an excessive activation. Likely, this effect is due to phosphatidylinositol 4,5-bisphosphate (PIP2) depletion that leads to modification of TRPM8 channel activity, shifting voltage dependence towards more positive potentials. This phenomenon needs further evaluation and confirmation that would allow us to understand better the role of this channel and to develop new therapeutic strategies for controlling pain. Experimental approach: To understand the role of TRPM8 in pain perception, we tested two specific TRPM8-modulating compounds, an antagonist (IGM-18) and an agonist (IGM-5), in either acute or chronic animal pain models using male Sprague-Dawley rats or CD1 mice, after systemic or topical routes of administration. Results: IGM-18 and IGM-5 were fully characterized in vivo. The wet-dog shake test and the body temperature measurements highlighted the antagonist activity of IGM-18 on TRPM8 channels. Moreover, IGM-18 exerted an analgesic effect on formalin-induced orofacial pain and chronic constriction injury-induced neuropathic pain, demonstrating the involvement of TRPM8 channels in these two pain models. Finally, the results were consistent with TRPM8 downregulation by agonist IGM-5, due to its excessive activation. Conclusions: TRPM8 channels are strongly involved in pain modulation, and their selective antagonist is able to reduce both acute and chronic pain

    S-wave Meson-Meson Scattering from Unitarized U(3) Chiral Lagrangians

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    An investigation of the s-wave channels in meson-meson scattering is performed within a U(3) chiral unitary approach. Our calculations are based on a chiral effective Lagrangian which includes the eta' as an explicit degree of freedom and incorporates important features of the underlying QCD Lagrangian such as the axial U(1) anomaly. We employ a coupled channel Bethe-Salpeter equation to generate poles from composed states of two pseudoscalar mesons. Our results are compared with experimental phase shifts up to 1.5 GeV and effects of the eta' within this scheme are discussed.Comment: 18 pages, 6 figure

    Effect of central nervous system (CNS) metastases in a real-world multicenter cohort study of Spanish ALK-positive non-small cell lung cancer (NSCLC) patients (p)

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    Background: CNS is a common site of metastases in patients with ALK-positive NSCLC. CNS metastases are associated with a number of deleterious effects, such as reduction in quality of life. However, the relationship between brain metastases and prognosis remains unclear. We aimed to evaluate the effect of CNS metastases on overall survival (OS) in a multicenter cohort of Spanish ALK-positive NSCLC patients diagnosed between 2008 and 2017. Methods: We included patients with stage IV at diagnoses, followed up to April 2018; OS (months [m]) was estimated with the Kaplan-Meier method. Survival curves were compared between groups of patients using the log-rank test. Hazard risk (HR) to death was estimated with multivariable Cox model. Results: Out of 163 patients in the cohort, a total of 116 were evaluated, with a median of follow-up of 29.2 m and 59 deaths reported. Characteristics at diagnosis were a median age of 58 years, 50% female, 58.6% never-smokers, 54.3% with comorbidities, PS by ECOG 0-1 93.1%. CNS metastases (median number of lesions 6) were present in 43.1% of patients and 34% of patients with CNS metastases were treated with local therapy (11.8 % local radiotherapy and 76.5% holocraneal radiotherapy). ALK inhibitors as first line and second line treatment were administered to 45.5% and 78.6% of patients, respectively. The median OS was 39 months; OS in patients with CNS metastases at diagnosis was 34.4 m and 39.0 m in those without CNS metastases at diagnosis (p=.9). In patients without CNS metastases at baseline (n=60), 22 developed CNS, with a median OS greater than in those without CNS metastases during follow-up, although the difference is not significant (45.5 m vs 33.3 m; p=.9). There were 81 patients who presented with metastases in more than one organ and 33 patients with metastases in a single organ. The risk of death increased as the number of metastatic organs at diagnoses increased (HR=1.26, p=.0305), with worse OS in those presenting with liver metastases at diagnoses (21.1%, OS: 20 m), compared to those without tumor involvement (OS: 45.4 m; p =.008). Conclusions: OS was similar for ALK-positive NSCLC patients with and without CNS metastases at diagnoses. OS was worse as the number of metastatic organs at diagnosis increased, with liver metastases being associated with the highest risk of mortality

    Effectiveness, cost-effectiveness and cost-benefit of a single annual professional intervention for the prevention of childhood dental caries in a remote rural Indigenous community

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    Background The aim of the study is to reduce the high prevalence of tooth decay in children in a remote, rural Indigenous community in Australia, by application of a single annual dental preventive intervention. The study seeks to (1) assess the effectiveness of an annual oral health preventive intervention in slowing the incidence of dental caries in children in this community, (2) identify the mediating role of known risk factors for dental caries and (3) assess the cost-effectiveness and cost-benefit of the intervention. Methods/design The intervention is novel in that most dental preventive interventions require regular re-application, which is not possible in resource constrained communities. While tooth decay is preventable, self-care and healthy habits are lacking in these communities, placing more emphasis on health services to deliver an effective dental preventive intervention. Importantly, the study will assess cost-benefit and cost-effectiveness for broader implementation across similar communities in Australia and internationally. Discussion There is an urgent need to reduce the burden of dental decay in these communities, by implementing effective, cost-effective, feasible and sustainable dental prevention programs. Expected outcomes of this study include improved oral and general health of children within the community; an understanding of the costs associated with the intervention provided, and its comparison with the costs of allowing new lesions to develop, with associated treatment costs. Findings should be generalisable to similar communities around the world. The research is registered with the Australian New Zealand Clinical Trials Registry (ANZCTR), registration number ACTRN12615000693527; date of registration: 3rd July 2015
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