29 research outputs found

    Colorimetric nanofibers as optical sensors

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    Sensors play a major role in many applications today, ranging from biomedicine to safety equipment, where they detect and warn us about changes in the environment. Nanofibers, characterized by high porosity, flexibility, and a large specific surface area, are the ideal material for ultrasensitive, fastresponding, and user-friendly sensor design. Indeed, a large specific surface area increases the sensitivity and response time of the sensor as the contact area with the analyte is enlarged. Thanks to the flexibility of membranes, nanofibrous sensors cannot only be applied in high-end analyte detection, but also in personal, daily use. Many different nanofibrous sensors have already been designed; albeit, the most straightforward and easiest-to-interpret sensor response is a visual change in color, which is of particular interest in the case of warning signals. Recently, many researchers have focused on the design of so-called colorimetric nanofibers, which typically involve the incorporation of a colorimetric functionality into the nanofibrous matrix. Many different strategies have been used and explored for colorimetric nanofibrous sensor design, which are outlined in this feature article. The many examples and applications demonstrate the value of colorimetric nanofibers for advanced optical sensor design, and could provide directions for future research in this area

    When, how and why to treat the neck in patients with esthesioneuroblastoma: a review.

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    Item does not contain fulltextEsthesioneuroblastoma is an uncommon tumor that presents in the sinonasal cavity and anterior skull base. Cervical metastases are not frequently found on initial presentation but eventually occur in 20-25% of these patients. This presents the treating physician with the difficult decision as to how and when to treat the neck in this disease. The aims of this study were to provide a comprehensive review of the incidence of N+ disease at presentation, make recommendations about the optimal treatment strategy of patients with N+ disease, explain the role of elective neck treatment in patients with N0 disease, and comment on treatment of patients with late cervical metastases that require salvage therapy, using the literature review of the incidence and treatment of neck disease in patients with esthesioneuroblastoma. This review revealed an approximately 5-8% incidence of cervical nodal metastasis at the time of presentation. Combined modality therapy with surgery and radiotherapy is recommended to treat the N+ neck at the time of diagnosis and later. Chemotherapy may have a role combined with radiation treatment, but there are little data to support this. There is limited evidence to substantiate the use of elective neck dissection or elective radiotherapy in the clinically and radiologically N0 neck. Patients who have late cervical metastases have a clear survival advantage (59 vs. 14%) when treated with combined surgery and radiotherapy relative to single modality methods alone. The results indicate that the management of the neck in esthesioneuroblastoma continues to be a significant challenge in the treatment algorithm of these complex patients.1 november 201

    Carotenoids, birdsong and oxidative status : administration of dietary lutein is associated with an increase in song rate and circulating antioxidants (albumin and cholesterol) and a decrease in oxidative damage

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    Despite the appealing hypothesis that carotenoid-based colouration signals oxidative status, evidence supporting the antioxidant function of these pigments is scarce. Recent studies have shown that lutein, the most common carotenoid used by birds, can enhance the expression of non-visual traits, such as birdsong. Nevertheless, the underlying physiological mechanisms remain unclear. In this study we hypothesized that male European starlings (Sturnus vulgaris) fed extra lutein increase their song rate as a consequence of an improved oxidative status. Although birdsong may be especially sensitive to the redox status, this has, to the best of our knowledge, never been tested. Together with the determination of circulating oxidative damage (ROMs, reactive oxygen metabolites), we quantified uric acid, albumin, total proteins, cholesterol, and testosterone, which are physiological parameters potentially sensitive to oxidation and/or related to both carotenoid functions and birdsong expression. We found that the birds fed extra lutein sang more frequently than control birds and showed an increase of albumin and cholesterol together with a decrease of oxidative damage. Moreover, we could show that song rate was associated with high levels of albumin and cholesterol and low levels of oxidative damage, independently from testosterone levels. Our study shows for the first time that song rate honestly signals the oxidative status of males and that dietary lutein is associated with the circulation of albumin and cholesterol in birds, providing a novel insight to the theoretical framework related to the honest signalling of carotenoid-based traits
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