244 research outputs found

    Lipidoid-Coated Iron Oxide Nanoparticles for Efficient DNA and siRNA delivery

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    The safe, targeted and effective delivery of gene therapeutics remains a significant barrier to their broad clinical application. Here we develop a magnetic nucleic acid delivery system composed of iron oxide nanoparticles and cationic lipid-like materials termed lipidoids. Coated nanoparticles are capable of delivering DNA and siRNA to cells in culture. The mean hydrodynamic size of these nanoparticles was systematically varied and optimized for delivery. While nanoparticles of different sizes showed similar siRNA delivery efficiency, nanoparticles of 50–100 nm displayed optimal DNA delivery activity. The application of an external magnetic field significantly enhanced the efficiency of nucleic acid delivery, with performance exceeding that of the commercially available lipid-based reagent, Lipofectamine 2000. The iron oxide nanoparticle delivery platform developed here offers the potential for magnetically guided targeting, as well as an opportunity to combine gene therapy with MRI imaging and magnetic hyperthermia.National Heart, Lung, and Blood InstituteNational Institutes of Health (U.S.) (Program of Excellence in Nanotechnology (PEN) Award, Contract #HHSN268201000045C

    Learn to Spot Phishing URLs with the Android NoPhish App

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    Part 3: Tools and Applications for TeachingInternational audiencePhishing is a münich issue in today’s Internet. It can have financial or personal consequences. Attacks continue to become more and more sophisticated and the advanced ones (including spear phishing) can only be detected if people carefully check URLs – be it in messages or in the address bar of the web browser. We developed a game-based smartphone app – NoPhish – to educate people in accessing, parsing and checking URLs; i.e. enabling them to distinguish between trustworthy and non-trustworthy messages and websites. Throughout several levels of the game information is provided and phishing detection is exercised in a playful manner. Several learning principles were applied and the interfaces and texts were developed in a user-centered design

    Magnetic resonance imaging (MRI) contrast agents for tumor diagnosis

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    10.1260/2040-2295.4.1.23Journal of Healthcare Engineering4123-4

    Magnetic hyperthermia controlled drug release in the GI tract : solving the problem of detection

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    Drug delivery to the gastrointestinal (GI) tract is highly challenging due to the harsh environments any drug- delivery vehicle must experience before it releases it’s drug payload. Effective targeted drug delivery systems often rely on external stimuli to effect release, therefore knowing the exact location of the capsule and when to apply an external stimulus is paramount. We present a drug delivery system for the GI tract based on coating standard gelatin drug capsules with a model eicosane- superparamagnetic iron oxide nanoparticle composite coating, which is activated using magnetic hyperthermia as an on-demand release mechanism to heat and melt the coating. We also show that the capsules can be readily detected via rapid X-ray computed tomography (CT) and magnetic resonance imaging (MRI), vital for progressing such a system towards clinical applications. This also offers the opportunity to image the dispersion of the drug payload post release. These imaging techniques also influenced capsule content and design and the delivered dosage form. The ability to easily change design demonstrates the versatility of this system, a vital advantage for modern, patient-specific medicine

    Dating Business Cycles in a Historical Perspective: Evidence for Switzerland

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    In this study we suggest a chronology of the classical business cycle in Switzerland. To this end we use two approaches: the approach of Artis et al. (2004) and an approach based on Markov-switching models (Hamilton, 1989). Our results show that similar conclusions can be reached by applying the two methodologies. Another result is that the chronology obtained displays high concordance with the chronology derived for the Euro Area by the CEPR Business Cycle Dating Committee. A further contribution of our study is that we determine the sensitivity of the chronology obtained with respect to a particular GDP vintage used. For this purpose we employ the real-time database that contains 53 vintages of GDP data starting from 1997Q4 until 2010Q4. The main result of this robustness exercise is that the chronology obtained is stable across different vintages, although some minor differences across vintages can be detected

    Shock Identification of Macroeconomic Forecasts Based on Daily Panels

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    This paper proposes a new procedure for shock identification of macroeconomic forecasts based on factor analysis. Our identification scheme for information shocks relies on data reduction techniques for daily panels and the recognition that macroeconomic releases exhibit a high level of clustering. A large number of data releases on a single day is of considerable practical interest not only for the estimation but also for the identification of the factor model. The clustering of cross-sectional information facilitates the interpretation of the forecast innovations as real or as nominal information shocks. An empirical application is provided for Swiss inflation. We show that (i) the monetary policy shocks generate an asymmetric response to inflation, (ii) the pass-through for consumer price index inflation is weak, and (iii) the information shocks to inflation are not synchronized

    "Nanohybrids" based on pH-responsive hydrogels and inorganic nanoparticles for drug delivery and sensor applications.

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    Allyl-PEG capped inorganic NPs, including magnetic iron oxide (IONPs), fluorescent CdSe/ZnS quantum dots (QDs), and metallic gold (AuNPs of 5 and 10 nm) both individually and in combination, were covalently attached to pH-responsive poly(2-vinylpyridine-co-divinylbenzene) nanogels via a facile and robust one-step surfactant-free emulsion polymerization procedure. Control of the NPs associated to the nanogels was achieved by the late injection of the NPs to the polymerization solution at a stage when just polymeric radicals were present. Remarkably, by varying the total amount of NPs injected, the swelling behavior could be affected. Furthermore, the magnetic response as well as the optical features of the nanogels containing either IONPs or QDs could be modified. In addition, a radical quenching in case of gold nanoparticles was observed, thus affecting the final nanogel geometry

    Recommendations for Pregnancy in Rare Inherited Anemias

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    Rare inherited anemias are a subset of anemias caused by a genetic defect along one of the several stages of erythropoiesis or in different cellular components that affect red blood cell integrity, and thus its lifespan. Due to their low prevalence, several complications on growth and development, and multi-organ system damage are not yet well defined. Moreover, during the last decade there has been a lack of proper understanding of the impact of rare anemias on maternal and fetal outcomes. In addition, there are no clear-cut guidelines outlining the pathophysiological trends and management options unique to this special population. Here, we present on behalf of the European Hematology Association, evidence- and consensus-based guidelines, established by an international group of experts in different fields, including hematologists, gynecologists, general practitioners, medical geneticists, and experts in rare inherited anemias from various European countries for standardized and appropriate choice of therapeutic interventions for the management of pregnancy in rare inherited anemias, including Diamond-Blackfan Anemia, Congenital Dyserythropoietic Anemias, Thalassemia, Sickle Cell Disease, Enzyme deficiency and Red cell membrane disorders

    Effects of Aging and Cyclosporin A on Collagen Turnover in Human Gingiva

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    BACKGROUND: WE AIMED AT CHARACTERIZING THE AGING GINGIVA ANALYZING: i) collagen content and turnover in human gingival tissues and fibroblasts obtained from healthy young and aging subjects. ii) the effect of cyclosporin A administration in human cultured gingival fibroblasts obtained from aging compared to young subjects. METHODS: Morphological analysis was performed on haematoxylin-eosin and Sirius red stained paraffin-embedded gingival biopsies from young and aging healthy subjects. The expression of the main genes and proteins involved in collagen turnover were determined by real time PCR, dot blot and SDS-zymography on cultured young and aging gingival fibroblasts, and after cyclosporin A administration. RESULTS: Our results suggest that in healthy aged people, gingival connective tissue is characterized by a similar collagen content and turnover. Collagen turnover pathways are similarly affected by cyclosporin A treatment in young and aging gingival fibroblasts. CONCLUSIONS: Cyclosporin A administration affects gingival collagen turnover pathways in young and aging fibroblasts at the same extent, suggesting that during aging cyclosporin A administration is not related to relevant collagen turnover modifications

    IGF-1 Induction by Acylated Steryl β-Glucosides Found in a Pre-Germinated Brown Rice Diet Reduces Oxidative Stress in Streptozotocin-Induced Diabetes

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    BACKGROUND: The pathology of diabetic neuropathy involves oxidative stress on pancreatic β-cells, and is related to decreased levels of Insulin-like growth factor 1 (IGF-1). Acylated steryl β-glucoside (PR-ASG) found in pre-germiated brown rice is a bioactive substance exhibiting properties that enhance activity of homocysteine-thiolactonase (HTase), reducing oxidative stress in diabetic neuropathy. The biological importance of PR-ASG in pancreatic β-cells remains unknown. Here we examined the effects of PR-ASG on IGF-1 and glucose metabolism in β-cells exposed to oxidative stress. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, a pre-germinated brown rice (PR)-diet was tested in streptozotocin (STZ)-induced diabetic rats. Compared with diabetic rats fed control diets, the PR-diet fed rats showed an improvement of serum metabolic and neurophysiological parameters. In addition, IGF-1 levels were found to be increased in the serum, liver, and pancreas of diabetic rats fed the PR-diet. The increased IGF-1 level in the pancreas led us to hypothesize that PR-ASG is protective for islet β-cells against the extensive injury of advanced or severe diabetes. Thus we examined PR-ASG to determine whether it showed anti-apoptotic, pro-proliferative effects on the insulin-secreting β-cells line, INS-1; and additionally, whether PR-ASG stimulated IGF-1 autocrine secretion/IGF-1-dependent glucose metabolism. We have demonstrated for the first time that PR-ASG increases IGF-1 production and secretion from pancreatic β-cells. CONCLUSION/SIGNIFICANCE: These findings suggest that PR-ASG may affect pancreatic β-cells through the activation of an IGF-1-dependent mechanism in the diabetic condition. Thus, intake of pre-germinated brown rice may have a beneficial effect in the treatment of diabetes, in particular diabetic neuropathy
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