880 research outputs found

    Epigenetic and genetic landscape of uterine leiomyomas: a current view over a common gynecological disease

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    Purpose: Despite the numerous studies on the factors involved in the genesis and growth of uterine leiomyomas, the pathogenesis of these tumors remains unknown. Intrinsic abnormalities of the myometrium, abnormal myometrial receptors for estrogen, and hormonal changes or altered responses to ischemic damage during the menstrual period may be responsible for the initiation of (epi)genetic changes found in these tumors. Considering these elements, we aimed to offer an overview about epigenetic and genetic landscape of uterine leiomyomas. Methods: Narrative overview, synthesizing the findings of literature retrieved from searches of computerized databases. Results: Several studies showed that leiomyomas have a monoclonal origin. Accumulating evidence converges on the risk factors and mechanisms of tumorigenesis: the translocation t (12;14) and deletion of 7q were found in the highest percentages of recurrence; dysregulation of the HMGA2 gene has been mapped within the critical 12q14-q15 locus. Estrogen and progesterone are recognized as promoters of tumor growth, and the potential role of environmental estrogens has been poorly explored. The growth factors with mitogenic activity, such as transforming growth factor-β3, fibroblast growth factor, epidermal growth factor, and insulin-like growth factor-I are elevated in fibroids and may have a role as effectors of the tumor promotion. Conclusion: The new clues on genetics and epigenetics, as well as about the growth factors that control normal and pathological myometrial cellular biology may be of great help for the development of new effective and less invasive therapeutic strategies in the near future

    Preliminary results of a single-arm pilot study to assess the safety and efficacy of visnadine, prenylflavonoids and bovine colostrum in postmenopausal sexually active women affected by vulvovaginal atrophy

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    This single-arm pilot study enrolled 47 post-menopausal women affected by vulvovaginal atrophy (VVA). The Vaginal Health Index Score (VHIS) was evaluated for all women and all completed the Female Sexual Function Index (FSFI) questionnaire at baseline (T0) and after 15 days of vaginal cream treatment with one application per day (T1). Following treatment there was a significant improvement in all VHIS parameters and total score (p < 0.0001). Similarly, there was a significant improvement on four FSFI domains (lubrication, orgasm, satisfaction and pain) and total score (p = 0.001). None of the patients reported any local or systemic side-effects during treatment

    Search for gamma-ray emission from magnetars with the Fermi Large Area Telescope

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    We report on the search for 0.1-10 GeV emission from magnetars in 17 months of Fermi Large Area Telescope (LAT) observations. No significant evidence for gamma-ray emission from any of the currently-known magnetars is found. The most stringent upper limits to date on their persistent emission in the Fermi-LAT energy range are estimated between ~10^{-12}-10^{-10} erg/s/cm2, depending on the source. We also searched for gamma-ray pulsations and possible outbursts, also with no significant detection. The upper limits derived support the presence of a cut-off at an energy below a few MeV in the persistent emission of magnetars. They also show the likely need for a revision of current models of outer gap emission from strongly magnetized pulsars, which, in some realizations, predict detectable GeV emission from magnetars at flux levels exceeding the upper limits identified here using the Fermi-LAT observations.Comment: ApJ Letters in press; Corresponding authors: Caliandro G. A., Hadasch D., Rea N., Burnett

    Detection of Gamma-Ray Emission from the Starburst Galaxies M82 and NGC 253 with the Large Area Telescope on Fermi

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    We report the detection of high-energy gamma-ray emission from two starburst galaxies using data obtained with the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. Steady point-like emission above 200 MeV has been detected at significance levels of 6.8 sigma and 4.8 sigma respectively, from sources positionally coincident with locations of the starburst galaxies M82 and NGC 253. The total fluxes of the sources are consistent with gamma-ray emission originating from the interaction of cosmic rays with local interstellar gas and radiation fields and constitute evidence for a link between massive star formation and gamma-ray emission in star-forming galaxies.Comment: Submitted to ApJ Letter

    Fermi Gamma-ray Imaging of a Radio Galaxy

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    The Fermi Gamma-ray Space Telescope has detected the gamma-ray glow emanating from the giant radio lobes of the radio galaxy Centaurus A. The resolved gamma-ray image shows the lobes clearly separated from the central active source. In contrast to all other active galaxies detected so far in high-energy gamma-rays, the lobe flux constitutes a considerable portion (>1/2) of the total source emission. The gamma-ray emission from the lobes is interpreted as inverse Compton scattered relic radiation from the cosmic microwave background (CMB), with additional contribution at higher energies from the infrared-to-optical extragalactic background light (EBL). These measurements provide gamma-ray constraints on the magnetic field and particle energy content in radio galaxy lobes, and a promising method to probe the cosmic relic photon fields.Comment: 27 pages, includes Supplementary Online Material; corresponding authors: C.C. Cheung, Y. Fukazawa, J. Knodlseder, L. Stawar

    Fermi Large Area Telescope observations of PSR J1836+5925

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    The discovery of the gamma-ray pulsar PSR J1836+5925, powering the formerly unidentified EGRET source 3EG J1835+5918, was one of the early accomplishments of the Fermi Large Area Telescope (LAT). Sitting 25 degrees off the Galactic plane, PSR J1836+5925 is a 173 ms pulsar with a characteristic age of 1.8 million years, a spindown luminosity of 1.1×1034\times10^{34} erg s1^{-1}, and a large off-peak emission component, making it quite unusual among the known gamma-ray pulsar population. We present an analysis of one year of LAT data, including an updated timing solution, detailed spectral results and a long-term light curve showing no indication of variability. No evidence for a surrounding pulsar wind nebula is seen and the spectral characteristics of the off-peak emission indicate it is likely magnetospheric. Analysis of recent XMM observations of the X-ray counterpart yields a detailed characterization of its spectrum, which, like Geminga, is consistent with that of a neutron star showing evidence for both magnetospheric and thermal emission.Comment: Accepted to Astrophysical Journa
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