188 research outputs found
Hepatitis B immunity in teenagers vaccinated as infants: an Italian 17-year follow-up study
AbstractWe assessed the persistence of hepatitis B surface antigen antibody (anti-HBs) and immune memory in a cohort of 571 teenagers vaccinated against hepatitis B as infants, 17 years earlier. Vaccinees were followed-up in 2003 and in 2010 (i.e. 10 years and 17 years after primary vaccination, respectively). When tested in 2003, 199 vaccinees (group A) had anti-HBs <10 mIU/mL and were boosted, 372 (group B) were not boosted because they had anti-HBs ≥10 mIU/mL (n = 344) or refused booster (n = 28) despite anti-HBs <10 mIU/mL. In 2010, 72.9% (416/571) of participants had anti-HBs ≥10 mIU/mL (67.3% in group A vs. 75.8% in group B; p 0.03). The geometric mean concentrations (GMCs) were similar in both groups. Between 2003 and 2010, anti-HBs concentrations in previously boosted individuals markedly declined with GMC dropping from 486 to 27.7 mIU/mL (p <0.001). Fifteen vaccinees showed a marked increase of antibody, possibly due to natural booster. In 2010, 96 individuals (37 of group A and 59 of group B) with anti-HBs <10 mIU/mL were boosted; all vaccinees of the former group and all but two of the latter had an anamnestic response. Post-booster GMC was higher in group B (895.6 vs. 492.2 mIU/mL; p 0.039). This finding shows that the immune memory for HBsAg persists beyond the time at which anti-HBs disappears, conferring long-term protection
Infections caused by filamentous fungi in patients with hematologic malignancies. A report of 391 cases by GIMEMA Infection Program.
BACKGROUND AND OBJECTIVES: To evaluate the clinical characteristics of patients with hematologic malignancies developing a filamentous fungi infection (FFI) and to define the prognostic factors for their outcome.
DESIGN AND METHODS: A retrospective study, conducted on patients admitted to 14 Hematology divisions of tertiary care or university hospitals, participating in the GIMEMA Infection Program, over a ten-year period (1988-1997). The study included patients with hematological malignancies and a histologically and/or microbiologically proven or probable FFI.
RESULTS: We included 391 patients (male/female: 262/129, median age 49 years) with hematologic malignancies (225 acute myeloid leukemia, 67 acute lymphocytic leukemia, 30 chronic myeloid leukemia, 22 non-Hodgkin's lymphoma, 12 myelodysplastic syndrome, 10 aplastic anemia, 7 Hodgkin's disease, 8 chronic lymphocytic leukemia, 5 multiple myeloma, and 5 hairy cell leukemia) who developed a proven FFI. Eighty percent of the patients had been neutropenic for an average of 14 days before the infection, and 71% had an absolute neutrophil count lower than 0.5 x 10(9)/L at the time of FFI diagnosis. The primary sites of infection were: lungs (85%), nose and paranasal sinus (10%), and other sites (5%). The diagnosis was made while still alive in 310 patients (79%), and at autopsy in the remaining 81 patients (21%). Chest X-ray was diagnostic in 77% of patients with pulmonary FFI, while computed tomography (CT) scan of the thorax was positive in 95% of cases. A significant diagnostic advantage for CT scan was observed in 145 patients who had both a chest X-ray and CT scan. Aspergillus was identified as the cause of FFI in 296 patients, Mucorales in 45 patients, Fusarium in 6 patients and other filamentous fungi species in 4 patients, while in a further 40 patients no agent was identifiable. The overall mortality rate three months after the diagnosis of FFI was 74%, and fungal infection had been the cause of death in 51% of patients.
INTERPRETATION AND CONCLUSIONS: Our retrospective study shows that FFI still remains a life-threatening complication in neutropenic patients. Despite appropriate treatment, half of the patients die due to this complication. The use of glucocorticoids and recovery from neutropenia are the most important prognostic factors. Mucorales infections are associated with a significantly poorer prognosis than those due to Aspergillus spp
Positivity of HIV, hepatitis B and hepatitis C in patients enrolled in a confidential self-exclusion system of blood donation: a cross-sectional analytical study
Search for gamma-ray emission from magnetars with the Fermi Large Area Telescope
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
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
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
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 erg s, 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
A change in the optical polarization associated with a gamma-ray flare in the blazar 3C 279
It is widely accepted that strong and variable radiation detected over all
accessible energy bands in a number of active galaxies arises from a
relativistic, Doppler-boosted jet pointing close to our line of sight. The size
of the emitting zone and the location of this region relative to the central
supermassive black hole are, however, poorly known, with estimates ranging from
light-hours to a light-year or more. Here we report the coincidence of a
gamma-ray flare with a dramatic change of optical polarization angle. This
provides evidence for co-spatiality of optical and gamma-ray emission regions
and indicates a highly ordered jet magnetic field. The results also require a
non-axisymmetric structure of the emission zone, implying a curved trajectory
for the emitting material within the jet, with the dissipation region located
at a considerable distance from the black hole, at about 10^5 gravitational
radii.Comment: Published in Nature issued on 18 February 2010. Corresponding
authors: Masaaki Hayashida and Greg Madejsk
Calcium ion currents mediating oocyte maturation events
During maturation, the last phase of oogenesis, the oocyte undergoes several changes which prepare it to be ovulated and fertilized. Immature oocytes are arrested in the first meiotic process prophase, that is morphologically identified by a germinal vesicle. The removal of the first meiotic block marks the initiation of maturation. Although a large number of molecules are involved in complex sequences of events, there is evidence that a calcium increase plays a pivotal role in meiosis re-initiation. It is well established that, during this process, calcium is released from the intracellular stores, whereas less is known on the role of external calcium entering the cell through the plasma membrane ion channels. This review is focused on the functional role of calcium currents during oocyte maturation in all the species, from invertebrates to mammals. The emerging role of specific L-type calcium channels will be discussed
Clinical practice guidelines for the prevention and treatment of EGFR inhibitor-associated dermatologic toxicities
Background Epidermal growth factor receptor inhibitors (EGFRI) produce various dermatologic side effects in the majority of patients, and guidelines are crucial for the prevention and treatment of these untoward events. The purpose of this panel was to develop evidence-based recommendations for EGFRI-associated dermatologic toxicities. Methods A multinational, interdisciplinary panel of experts in supportive care in cancer reviewed pertinent studies using established criteria in order to develop first-generation recommendations for EGFRI-associated dermatologic toxicities. Results Prophylactic and reactive recommendations for papulopustular (acneiform) rash, hair changes, radiation dermatitis, pruritus, mucositis, xerosis/fissures, and paronychia are presented, as well as general dermatologic recommendations when possible. Conclusion Prevention and management of EGFRI-related dermatologic toxicities is critical to maintain patients’ health-related quality of life and dose intensity of antineoplastic regimens. More rigorous investigation of these toxicities is warranted to improve preventive and treatment strategies
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