277 research outputs found

    Enteric Nervous System Abnormalities in Ulcerative Colitis

    Get PDF
    In the recent years, there is increasing evidence highlighting the crucial role played by ENS in intestinal inflammation, as demonstrated by the growing numbers of studies looking at both morphological and functional alterations in the ENS and its cellular elements, neurons and glial cells. These observations are the results of investigations carried out in both experimental animal models and in intestinal tissues of patients with inflammatory bowel disease. Although morpho-functional abnormalities of the ENS of UC patients have been consistently reported, additional studies are necessary to better understand the changes in the enteric cells, including neurons (of both submucosal and myenteric layers) and glial cells, which control gut functions, such as colonic motility and secretion, in the inflamed gut. This approach will help to prevent enteric neuropathies associated with inflammation and pave the way to future therapeutic options. Targeting neuronal and/or glial alterations during the course of inflammation may represent a novel approach to diminish the entity of tissue damage as well as the lack of long-term effectiveness of classical immunosuppressant agents used in the treatment of UC. Moreover, additional studies investigating the relationship between ENS and immune cells are warranted in order to carry out an in-depth assessment of the role of neurons, glial cells and their derived factors in the modulation of immune/inflammatory responses in the human gut, in light of establishment of new therapeutic approaches towards the treatment of gut inflammatory diseases. One of the main questions that still need to be addressed to is whether the alterations of the ENS precede or are secondary to the inflammatory process within the gut. This will hopefully help to predict the disease outcome in UC, that until now remains a challenge, and for better understanding of the pathogenesis of this disease. In conclusion, the complex interactions of the ENS and the other systems during gut inflammation require a broad perspective from neurophysiology, biochemistry and immunology to completely understand the regulation of inflammatory processes involved in UC. Therefore, important progress in this field can only be achieved by interdisciplinary approaches. Further research in this direction needs to be done for the discovery of longlasting, effective treatment for inflammatory diseases of the gut

    La formazione del docente di Scuola Primaria nell’interazione teoria-prassi

    Get PDF
    Teachers school of base has been among the most important themes of reflectionof the Italian school in the last twenty years. The education and theformation in fact together with the search historian critical of the formativetrials with the renewal of the didactic methodologies they not only evolvehim to change some social classes, of the relationships between individualand collectivity or to constitute him of new conditions of life of job andknowledge, but also to impose and the to converge of practical-scientificappeals, (you see the role of the socials middle, the technological innovation)at least as point of departure to the educational problem list. In subjectof formation teacher emerges by now a contradiction leading generallyalways among the traditional structure-function of the M. P.I., in the dialecticsamong the two logical natural-mind prevails.La formazione degli insegnanti della scuola di base è stata tra i più importantitemi di riflessione della scuola italiana nell’ultimo ventennio. L’educazionee l’istruzione infatti insieme alla ricerca storico critica dei processiformativi con il rinnovamento delle metodologie didattiche si evolvononon solo per il trasformarsi dei ceti sociali, dei rapporti fra individuo e collettivitào per il costituirsi di nuove condizioni di vita di lavoro e diconoscenza, ma anche per l’imporsi e il convergere di istanze pratico-scientifiche,(vedi il ruolo dei social media, l’innovazione tecnologica) almenocome punto di partenza alle problematiche educative. In materia di formazionedocente emerge ormai una contraddizione di fondo tra latradizionale struttura-funzione del M.P.I., in genere sempre più centralizzatadi ogni altra amministrazione statale, e le nuove spinte autonomistiche esocializzanti che dalla fine degli anni ‘60 hanno preso a circolare e che oggisi sono, spesso trasformate in Camarilles amministrativo-scolastiche

    S100B inhibitor pentamidine attenuates reactive gliosis and reduces neuronal loss in a mouse model of Alzheimer's disease

    Get PDF
    Among the different signaling molecules released during reactive gliosis occurring in Alzheimer’s disease (AD), the astrocytederived S100B protein plays a key role in neuroinflammation, one of the hallmarks of the disease. The use of pharmacological tools targeting S100B may be crucial to embank its effects and some of the pathological features of AD. The antiprotozoal drug pentamidine is a good candidate since it directly blocks S100B activity by inhibiting its interaction with the tumor suppressor p53. We used a mouse model of amyloid beta- (A-) induced AD, which is characterized by reactive gliosis and neuroinflammation in the brain, and we evaluated the effect of pentamidine on the main S100B-mediated events. Pentamidine caused the reduction of glial fibrillary acidic protein, S100B, and RAGE protein expression, which are signs of reactive gliosis, and induced p53 expression in astrocytes. Pentamidine also reduced the expression of proinflammatory mediators and markers, thus reducing neuroinflammation in AD brain. In parallel, we observed a significant neuroprotection exerted by pentamidine on CA1 pyramidal neurons. We demonstrated that pentamidine inhibits A-induced gliosis and neuroinflammation in an animal model of AD, thus playing a role in slowing down the course of the disease

    Critical currents and pinning forces in Nd2−xCexCuO4− thin films

    Get PDF
    Critical current density, Jc, and flux-pinning force density, Fp, have been investigated at different temperatures in electron-doped Nd2−xCexCuO4− thin films for magnetic fields, H, applied parallel to the c axis. The reduced pinning force density fFp /Fp max shows a clear scaling behavior when H is normalized to the irreversibility field H, indicating the presence of the same pinning mechanism in the investigated temperature range. Moreover the maximum of Fp as function of the field at each temperature depends linearly on H. The experimental data, interpreted using a modified Anderson-Kim description of the flux-creep theory, imply a magnetic field dependence of the activation energy UHH− with =0.8. This value indicates that in Nd2−xCexCuO4− a quasi-two-dimensional vortex system is present, intermediate between Bi-based and Y-based hole-doped compounds

    Critical temperature of triplet superconductor-ferromagnet bilayers as a probe for pairing symmetry

    Full text link
    Identifying superconducting materials with spin-polarized Cooper pairs is an important objective both for exploration of new fundamental physics and for cryogenic applications in spintronics and quantum sensing. We here compute the critical temperature TcT_c of the superconducting transition in a bilayer comprised of a superconductor with an intrinsic spin-triplet order parameter and a ferromagnet. We determine how TcT_c varies both with the thickness of the ferromagnet and its magnetization direction. We show that both the orbital and spin part of the triplet superconducting order parameter leave clear signatures in TcT_c which do not appear in a bilayer of a conventional s-wave superconductor and a ferromagnet. In particular, the dependence of TcT_c on these variables changes depending on whether or not the superconducting order parameter features Andreev bound-states and also changes qualitatively when the magnetization is rotated in the plane of the ferromagnetic film. Measurements of TcT_c in such bilayers are therefore useful to identify the pairing symmetry of intrinsic triplet superconductors

    Quasiparticles energy relaxation times in NbN/CuNi nanostripes from critical velocity measurements

    Get PDF
    The dynamic instability of the moving vortex lattice at high driving currents in NbN/CuNi-based and NbN nanostripes designed for optical detection has been studied. By applying the model proposed by Larkin and Ovchinnikov [Zh. Eksp. Teor. Fiz. 68, 1915 (1975)], from the critical velocity v∗ for the occurrence of the instability, it was possible to estimate the values of the quasiparticle relaxation times τE. The results show that the NbN/CuNi-based devices are characterized by shorter values of τE compared to that of NbN

    Local characterization of ferromagnetic properties in ferromagnet/superconductor bilayer by Point Contact Andreev Reflection Spectroscopy

    Full text link
    We realized point contact spectroscopy experiment on ferromagnet/superconductor bilayers. Differential conductance curves show several features that we explained within Bogoliubov-de Gennes formalism considering the presence of two interfaces in the normal-metal-tip/ferromagnet/superconductor device. We demonstrate that such configuration is suitable as local probe of the spin polarization and thickness of ferromagnetic layer, directly on bilayer areas. This is due to the high sensitivity of the Andreev surface states to the physical properties of the ferromagnetic interlayer

    Temperature dependence of resistivity of porous silicon formed on N-substrates

    Get PDF
    Results of measurement of resistivity of mesoporous silicon formed on n-type substrates in a wide temperature range are presented. Measurements show that at low temperatures there is a growth of resistance of four orders of magnitude compared to that at room temperature which occurs in a relatively narrow temperature range. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2063

    Novel Findings into AIRE Genetics and Functioning: Clinical Implications

    Get PDF
    Autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED), formerly known as autoimmune polyendocrine syndrome type 1, is a paradigm of a monogenic autoimmune disease caused by mutations of a gene, named autoimmune regulator (AIRE). AIRE acts as a transcription regulator that promotes immunological central tolerance by inducing the ectopic thymic expression of many tissue-specific antigens. Although the syndrome is a monogenic disease, it is characterized by a wide variability of the clinical expression with no significant correlation between genotype and phenotype. Indeed, many aspects regarding the exact role of AIRE and APECED pathogenesis still remain unraveled. In the last decades, several studies in APECED and in its mouse experimental counterpart have revealed new insights on how immune system learns self-tolerance. Moreover, novel interesting findings have extended our understanding of AIRE's function and regulation thus improving our knowledge on the pathogenesis of APECED. In this review, we will summarize recent novelties on molecular mechanisms underlying the development of APECED and their clinical implications
    corecore