2,270 research outputs found

    Electrochemistry of cyclic triimidazoles and their halo derivatives: A casebook for multiple equivalent centers and electrocatalysis

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    A family of cyclic triazines, based on the triimidazo[1,2-a:1\u2032,2\u2032-c:1\u2033,2\u2033-e][1,3,5]triazine scaffold, has recently caught attention due to its variegated solid state photoluminescent properties (e.g., crystallization induced emission, fluomechanochromism, dual fluorescence, room temperature ultralong phosphorescence), tuned by proper functionalization of the cyclic core. From an electrochemical point of view, this family of heteroaromatic cyclic triazines is unexplored. A cyclic voltammetry study is here performed aiming to clarify structure/electroactivity relationship. The peculiar molecular structure of this class of molecules offers a multi-approach case study, spanning from multiple equivalent redox site interactions in small hoops (due to ideally C3h symmetry) to carbon-halogen bond reactivity in the presence of catalytic metal electrode surfaces (for \u2013Br and \u2013I derivatives). Results point to a poor heteroannular aromaticity along the rigid, planar cyclotrimer, with each equivalent redox site acting quite independently. An unusually higher electrocatalytic performance of gold with respect to silver electrode for the electrocleavage of carbon-halogen bonds (that decreases by increasing number of halo substituents) is tentatively explained in term of a specific interaction between gold and the nitrogen-rich planar cyclotrimer platform

    Neural basis of anticipatory multisensory integration

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    The brain is able to gather different sensory information to enhance salient event perception, thus yielding a unified perceptual experience of multisensory events. Multisensory integration has been widely studied, and the literature supports the hypothesis that it can occur across various stages of stimulus processing, including both bottom-up and top-down control. However, evidence on anticipatory multisensory integration occurring in the fore period preceding the presentation of the expected stimulus in passive tasks, is missing. By means of event-related potentials (ERPs), it has been recently proposed that visual and auditory unimodal stimulations are preceded by sensory-specific readiness activities. Accordingly, in the present study, we tested the occurrence of multisensory integration in the endogenous anticipatory phase of sensory processing, combining visual and auditory stimuli during unimodal and multimodal passive ERP paradigms. Results showed that the modality-specific pre-stimulus ERP components (i.e., the auditory positivity-aP-and the visual negativity-vN-) started earlier and were larger in the multimodal stimulation compared with the sum of the ERPs elicited by the unimodal stimulations. The same amplitude effect was also present for the early auditory N1 and visual P1 components. This anticipatory multisensory effect seems to influence stimulus processing, boosting the magnitude of early stimulus processing. This paves the way for new perspectives on the neural basis of multisensory integration

    Breast tuberculosis: A case report of primary type mammary tuberculosis

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    Mammary tuberculosis is exceptional in developed countries. It can mimic an abscess or a granulomatous mastitis. In subjects coming from endemic areas, it is necessary to suspect a tuberculosis infection in case of recurrent mastitis refractory to antibiotics. Positivity of Quantiferon-TB Gold assay can help to confirm the clinical suspicion

    A comparative study of electrochemical, spectroscopic and structural properties of phenyl, thienyl and furyl substituted ethylenes

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    a detailed electrochemical and photophysical comparative study of three parallel series of phenyl, thienyl and furyl substituted ethylenes has been carried out, implemented by the computational calculation of selected terms. Relationships have been highlighted between molecular structure (number and type of aromatic rings) and important functional properties (in particular, electronic features and oligomerization ability). Interestingly, some of the studied heteroaryl-ethylenes show emission in the solid state displaying an aggregation-induced emission behavior

    Targeted photoimmunotherapy for cancer

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    Photodynamic therapy (PDT) is a clinically approved procedure that can exert a curative action against malignant cells. The treatment implies the administration of a photoactive molecular species that, upon absorption of visible or near infrared light, sensitizes the formation of reactive oxygen species. These species are cytotoxic and lead to tumor cell death, damage vasculature, and induce inflammation. Clinical investigations demonstrated that PDT is curative and does not compromise other treatment options. One of the major limitations of the original method was the low selectivity of the photoactive compounds for malignant over healthy tissues. The development of conjugates with antibodies has endowed photosensitizing molecules with targeting capability, so that the compounds are delivered with unprecedented precision to the site of action. Given their fluorescence emission capability, these supramolecular species are intrinsically theranostic agents

    Inspiratory effort and lung mechanics in spontaneously breathing patients with acute respiratory failure due to COVID-19. A matched control study.

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    Several physical and biological mechanisms can drive progression between the different phases of lung injury due to SARS-CoV-2 infection, thus modifying the mechanical properties and behavior of COVID-19 over time. In this research letter we have presented the findings of a registered clinical trial aimed at describing and comparing the inspiratory effort (primary outcome) and the breathing pattern of spontaneously breathing patients with ARF in COVID-19 and historically matched non-COVID-19 patients, either candidate to NIV. Moreover, we reported the response to a 2 hours NIV trial in the two groups. Spontaneously breathing COVID-19 at their early onset of acute respiratory failure with indication for NIV showed different mechanical characteristics and breathing pattern when compared with non-COVID-19

    Considerations for the optimal management of antibiotic therapy in elderly patients

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    Objectives: To maximise efficacy and minimise toxicity, special considerations are required for antibiotic prescription in elderly patients. This review aims to provide practical suggestions for the optimal management of antibiotic therapy in elderly patients. Methods: This was a narrative review. A literature search of published articles in the last 15 years on antibiotics and elderly patients was performed using the Cochrane Library and PubMed electronic databases. The three priority areas were identified: (i) pharmacokinetics/pharmacodynamics (PK/PD) for optimising dosage regimens and route of administration; (ii) antibiotic dosages in some special subpopulations; and (iii) treatment considerations relating to different antibiotic classes and their adverse events. Results: Clinicians should understand the altered PK/PD of drugs in this population owing to co-morbid conditions and normal physiological changes associated with ageing. The body of evidence justifies the need for individualised dose selection, especially in patients with impaired renal and liver function. Clinicians should be aware of the major drug–drug interactions commonly observed in the elderly as well as potential side effects. Conclusion: Antibiotic therapy in the elderly requires a comprehensive approach, including strategies to improve appropriate antibiotic prescribing, limit their use for uncomplicated infections and ensure the attainment of an optimal PK/PD target. To this purpose, further studies involving the elderly are needed to better understand the PK of antibiotics. Moreover, it is necessary to assess the role therapeutic drug monitoring in guiding antibiotic therapy in elderly patients in order to evaluate its impact on clinical outcome

    Rhodococcus equi Pneumonia in Kidney Transplant Recipient Affected by Acute Intermittent Porphyria: A Case Report

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    Rhodococcus equi is a gram-positive coccobacillus responsible for severe infections in patients with weakened immune systems. R equi generally causes pnumonia that may evolve into fatal systemic infection if left untreated. Here, we present a case of a 67-year-old woman affected by acute intermittent porphyria (AIP) who developed R equi pneumonia 7 months after kidney transplant. Although clinical features at presentation were nonspecific, lung computed tomography showed right perihilar consolidation with a mass-like appearance causing bronchial obstruction. Appropriate antibiotic including intravenous meropenem and oral azithromycin that was then switched to oral levofloxacin and oral azithromycin along with reduction of immunosuppressive therapy resolved pneumonia without provoking an acute attack of porphyria. AIP limited the choice of antibiotics for the treatment of R equi infection because some potentially porphyrinogenic antibacterial agents were avoided. Based on this experience, azithromycin and meropenem can be safely administered for the treatment of R Equi infection in patients with AIP

    Dasabuvir and Ombitasvir/Paritaprevir/Ritonavir with or without Ribavirin in Patients with HIV-HCV Coinfection. Real Life Interim Analysis of an Italian Multicentre Compassionate Use Program

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    Background and Aims: An HCV cure is now possible in a large proportion of HIV-HCV patient. We present real life results of a compassionate use program promoted by SIMIT (Infectious and Tropical Diseases Italian Society) of Dasabuvir and Ombitasvir/Paritaprevir/Ritonavir ± Ribavirin for 12 weeks in 213 HIV-HCV genotype 1 patients. Data on efficacy and tolerability of this strategy in HIV patients have been reported until now only in 43 non cirrhotic HIV subjects

    The Interaction of Hypericin with SARS-CoV-2 Reveals a Multimodal Antiviral Activity

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    Hypericin is a photosensitizing drug that is active against membrane-enveloped viruses and therefore constitutes a promising candidate for the treatment of SARS-CoV-2 infections. The antiviral efficacy of hypericin is largely determined by its affinity toward viral components and by the number of active molecules loaded on single viruses. Here we use an experimental approach to follow the interaction of hypericin with SARS-CoV-2, and we evaluate its antiviral efficacy, both in the dark and upon photoactivation. Binding to viral particles is directly visualized with fluorescence microscopy, and a strong affinity for the viral particles, most likely for the viral envelope, is measured spectroscopically. The loading of a maximum of approximately 30 molecules per viral particle is estimated, despite with marked heterogeneity among particles. Because of this interaction, nanomolar concentrations of photoactivated hypericin substantially reduce virus infectivity on Vero E6 cells, but a partial effect is also observed in dark conditions, suggesting multiple mechanisms of action for this drug
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