3,261 research outputs found

    Immune cells and microbiota response to iron starvation

    Get PDF
    Metal ions are essential for life on Earth, mostly as crucial components of all living organisms; indeed, they are necessary for bioenergetics functions as crucial redox catalysts. Due to the essential role of iron in biological processes, body iron content is finely regulated and is the battlefield of a tug-of-war between the host and the microbiota.Iron availability in the intestinal lumen could prevent or promote intestinal dysbiosis, although current data do not provide a definitive response. Recent data demonstrated that nutritional derived polyphenols explicit their anti-inflammatory functions sequestrating iron from immune cells. Here, we discuss whether nutritional iron chelators could be able to change the gut microbiota composition and prevent the intestinal dysbiosis associated with intestinal chronic inflammatory syndromes.Iron is lost by cellular exfoliation and occasional bleeding; it is absorbed from nutritional components. Heme is the most important source of dietary iron, while non-heme iron can be absorbed only in the duodenum and the beginning of the jejunum in pH permissive (acid) conditions. Western diets often contain large quantities of foods characterized by a high heme-iron content like meat, fish, and poultry, and small quantities of non-heme-iron content like vegetables, fruits, and nuts. Furthermore, nutritional substances can affect iron absorption: ascorbic acid is an efficient enhancer of non-heme-iron absorption, vice versa, phytic acid is known to be among the major iron absorption inhibitors, and iron-chelating substances like quercetin inhibit its absorption, likely due to loss of chelated-iron solubility.Iron deficiency is the most common cause of anemia worldwide and one of the most common complications observed in inflammatory bowel disease (IBD) patients due to gastrointestinal hemorrhages. In IBD patients, the guidelines for the management of iron deficiency are not entirely satisfactory because following oral iron supplementation patients sometimes report worsening of the IBD symptoms (1). Interestingly, iron supplemented diets can also show protective effects in dextran sodium sulfate (DSS)-induced colitis models. Constante et al. demonstrated that iron formulation dramatically changed the outcome of the DSS-induced colitis, as oral supplementation with ferrous bisglycinate but not ferric ethylenediaminetetraacetic acid enhanced the beneficial action of probiotics (2)

    Implementing Mindfulness in General Life and Organizations. Validation of the Time Flow Mindfulness Questionnaire for Effective Health Management

    Get PDF
    The primary purpose of the current research was to examine the psychometric properties of the Time Flow Mindfulness Questionnaire (TFMQ), a new self-report scale designed to measure cognitive, emotional, bodily, context-related, and action-related distracting inputs experienced by the mind during three different time windows of mindfulness practice (preliminary moments, during-the-practice, after-the-practice). The 42-item scale assesses the following second-order and first-order factors: Practice (preliminary, during), Benefits (short-term, long-term) and Benefits at work. Three studies were conducted. The first study assessed the factor structure and internal consistency on a sample of 141 mindfulness practitioners. Using a two-wave lagged design on a different sample of 46 trainees attending MBSR courses, the second study examined concurrent validity by performing correlations between the TFMQ and Five Facets Mindfulness Questionnaire (FFMQ). The third study (same sample as study 1) examined criterion validity by testing a structural equation model wherein mindfulness practice predicts job burnout, both directly and indirectly through mindfulness benefits at work. All studies relied on anonymous surveys. Our findings suggest that the TFMQ: a) has a factor structure consistent with the hypothesized conceptual dimensions; b) has good concurrent validity as demonstrated by significant correlations with the FFMQ dimensions; and c) consists of mindfulness dimensions that predict job burnout in organizations (i.e., criterion validity). The TFMQ is a valid and reliable mindfulness measure that may help a) practitioners gain awareness of different types of inputs that potentially distract the mind and mindfulness beneficial consequences, and b) organizations implement mindfulness in work-settings

    Metabolic syndrome and cardiovascular risk after liver transplantation: a single-center experience.

    Get PDF
    Excessive weight gain, hypertension, hyperlipidemia, and diabetes are frequently observed among orthotopic liver transplantation (OLT) patients. These alterations, which are probably multifactorial in origin, contribute to posttransplantation metabolic syndrome (PTMS), which increases the risk of cardiovascular events. We assessed the prevalence of PTMS (diagnosed according to modified NCEP Adult Treatment Panel III criteria) in 156 OLT patients undergoing regular follow-up after transplantation (median 68 months; range, 6 to 234 months). Several pre- and post-OLT data were collected to identify the factors associated with the presence of PTMS which was found in 28% of cases. The only independent predictive factors for PTMS were diabetes mellitus and patients who were overweight or obese before-OLT. The prevalence of PTSM was lower among patients on tacrolimus immunosuppression. In our population, 21% of patients showed a high cardiovascular risk score with a 4% incidence of cardiovascular events, which was higher among subjects with PTMS. Close follow-up is mandatory to prevent the development of PTMS mainly among overweight and diabetic patients before transplantation

    Hawking radiation in different coordinate settings: Complex paths approach

    Get PDF
    We apply the technique of complex paths to obtain Hawking radiation in different coordinate representations of the Schwarzschild space-time. The coordinate representations we consider do not possess a singularity at the horizon unlike the standard Schwarzschild coordinate. However, the event horizon manifests itself as a singularity in the expression for the semiclassical action. This singularity is regularized by using the method of complex paths and we find that Hawking radiation is recovered in these coordinates indicating the covariance of Hawking radiation as far as these coordinates are concerned.Comment: 18 pages, 2 figures, Uses IOP style file; final version; accepted in Class. Quant. Gra

    The "Peeking" Effect in Supervised Feature Selection on Diffusion Tensor Imaging Data

    Get PDF
    We read with great interest the article by Haller et al[1][1] in the February 2013 issue of the American Journal of Neuroradiology . The authors used whole-brain diffusion tensor imaging–derived fractional anisotropy (FA) data, skeletonized through use of the standard tract-based spatia

    Interactions of hadrons in the CALICE SiW ECAL prototype

    No full text
    This article presents results of test beams obtained for pions with energies between 2 and 10 GeV which interact in the volume of the highly granular CALICE Silicon-Tungsten electromagnetic calorimeter prototype (SiW ECAL). An algorithm optimised to ïŹnd interactions in the SiW ECAL at small hadron energies is developed. This allows identifying the interaction point in the calorimeter at an efficiency between 62% and 83% depending on the energy of the primary particle. The unprecedented granularity of the SiW ECAL allows for the distinction between different interaction types. This in turn permits more detailed examinations of hadronic models than was possible with traditional calorimeters. So far, it is possible to disentangle minimum ionising particle (MIP) events, elastic π-nucleus scattering and spallation reactions which lead to the start of a internuclear cascade or which result in a small number of highly ionising particles. Various observables are compared with predictions from hadronic physics lists as contained in the simulation toolkit geant4

    Fractal Analysis of MRI Data at 7 T: How Much Complex Is the Cerebral Cortex?

    Get PDF
    The human brain is a highly complex structure, which can be only partially described by conventional metrics derived from magnetic resonance imaging (MRI), such as volume, cortical thickness, and gyrification index. In the last years, the fractal dimension (FD) - a useful quantitative index of fractal geometry - has proven to well express the morphological complexity of the cerebral cortex. However, this complexity is likely higher than that we can observe using MRI scanners with 1.5 T or 3 T field strength. Ultrahigh-field MRI (UHF-MRI) improves imaging of smaller anatomical brain structures by exploring down to a submillimetric spatial resolution with higher signal-to-noise and contrast-to-noise ratios. Accordingly, we hypothesized that UHF-MRI might reveal a higher level of the structural complexity of the cerebral cortex. In this study, using an improved box-counting algorithm, we estimated the FD of the cerebral cortex in six public or private T1-weighted MRI datasets of young healthy subjects (for a total of 87 subjects), acquired at different field strengths (1.5 T, 3 T, and 7 T). Our results showed, for the first time, that MRI-derived FD values of the cerebral cortex imaged at 7 T were significantly higher than those observed at lower field strengths. UHF-MRI provides an anatomical definition not achievable at lower field strengths and can improve unveiling the real structural complexity of the human brain

    In vitro evidences of different fibroblast morpho-functional responses to red, near-infrared and violet-blue photobiomodulation: Clues for addressingwound healing

    Get PDF
    Although photobiomodulation (PBM) has proven promising to treat wounds, the lack of univocal guidelines and of a thorough understanding of light–tissue interactions hampers its mainstream adoption for wound healing promotion. This study compared murine and human fibroblast responses to PBM by red (635 ± 5 nm), near-infrared (NIR, 808 ± 1 nm), and violet-blue (405 ± 5 nm) light (0.4 J/cm2 energy density, 13 mW/cm2 power density). Cell viability was not altered by PBM treatments. Light and confocal laser scanning microscopy and biochemical analyses showed, in red PBM irradiated cells: F-actin assembly reduction, up-regulated expression of Ki67 proliferation marker and of vinculin in focal adhesions, type-1 collagen down-regulation, matrix metalloproteinase-2 and metalloproteinase-9 expression/functionality increase concomitant to their inhibitors (TIMP-1 and TIMP-2) decrease. Violet-blue and even more NIR PBM stimulated collagen expression/deposition and, likely, cell differentiation towards (proto)myofibroblast phenotype. Indeed, these cells exhibited a higher polygonal surface area, stress fiber-like structures, increased vinculin- and phospho-focal adhesion kinase-rich clusters and α-smooth muscle actin. This study may provide the experimental groundwork to support red, NIR, and violet-blue PBM as potential options to promote proliferative and matrix remodeling/maturation phases of wound healing, targeting fibroblasts, and to suggest the use of combined PBM treatments in the wound management setting
    • 

    corecore