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Azzari C.,University of Florence | Moriondo M.,University of Florence | Di Pietro P.,Instituto Giannina Gaslini | Di Bari C.,Azienda Ospedaliera Universitaria | And 10 more authors.
Italian Journal of Pediatrics | Year: 2015

Background: Invasive diseases (ID) caused by Streptococcus pneumoniae (S. pneumoniae), Haemophilus influenzae (H. influenzae), and Neisseria meningitidis are a major public health problem worldwide. Comprehensive data on the burden of bacteremia and ID in Italy, including data based on molecular techniques, are needed. Methods: We conducted a prospective, multi-centre, hospital-based study (GSK study identifier: 111334) to assess the burden of bacteremia and ID among children less than five years old with a fever of 39 °C or greater. Study participation involved a single medical examination, collection of blood for polymerase chain reaction (PCR) and blood culture, and collection of an oropharyngeal swab for colonization analysis by PCR. Results: Between May 2008 and June 2009, 4536 patients were screened, 944 were selected and 920 were enrolled in the study. There were 225 clinical diagnoses of ID, 9.8 % (22) of which were bacteremic. A diagnosis of sepsis was made for 38 cases, 5.3 % (2) of which were bacteremic. Among the 629 non-ID diagnoses, 1.6 % (10) were bacteremic. Among the 34 bacteremic cases, the most common diagnoses were community-acquired pneumonia (15/34), pleural effusion (4/34) and meningitis (4/34). S. pneumoniae was the most frequently detected bacteria among bacteremic cases (29/34) followed by H. influenzae (3/34). Ninety percent (27/30) of bacteremic patients with oropharyngeal swab results were colonized with the studied bacterial pathogens compared to 46.1 % (402/872) of non-bacteremic cases (p < 0.001). PCV7 (7-valent pneumococcal conjugate vaccine) vaccination was reported for 55.9 % (19/34) of bacteremic cases. S. pneumoniae serotypes were non-vaccine serotypes in children who had been vaccinated. Mean duration of hospitalization was longer for bacteremic cases versus non-bacteremic cases (13.6 versus 5.8 days). Conclusions: These results confirm that S. pneumoniae is one of the pathogens frequently responsible for invasive disease. © 2015 Azzari et al.


Vigna L.,Azienda Ospedaliera Maggiore della Carita | Matheoud R.,Azienda Ospedaliera Maggiore della Carita | Ridone S.,Radiation Protection Institute | Arginelli D.,Radiation Protection Institute | And 4 more authors.
Physica Medica | Year: 2011

[153Sm]Sm-EDTMP is a radiopharmaceutical used in palliation cares of bone metastases. The purpose of this study is to provide an explicit description of [153Sm]Sm-EDTMP pharmacokinetics, adopting a simple three-compartmental model with the analytical expressions calculating the rate constants and determining biodistribution parameters, like radiopharmaceutical uptake and clearance. This biokinetic model allowed us to calculate on an individual basis the dose to bone surface and to red bone marrow and to assess the degree of variability in dosimetric parameters using a fixed administered activity based only on patient weight.In this study twenty patients were enrolled and were treated with [153Sm]Sm-EDTMP, administering a fixed activity per kilogram (37 MBq/kg); blood and urine samples were collected during 24 h post treatment. The median value of the administered activity was 2.7 GBq.Blood clearance confirmed that an aliquot of [153Sm]Sm-EDTMP rapidly localizes and is retained in bone, while the remainder is rapidly cleared from the blood pool by the urinary system. Our data show a bi-exponential clearance from blood: the rapid component has a half life median value of 6 min (range: 2-24 min), while the slow one has a half life median value of 1.4 h (range: 0.6-5.8 h). Median value of the urinary excretion is 40 (range: 3-75) % of the administered activity.Our model shows the behaviour of a tracer which is distributed in the extracellular space of the body, localized in the skeleton and excreted via glomerular filtration. Half life median values of [153Sm]Sm-EDTMP transferring between compartments, T1/2 (blood→ECF), T1/2 (ECF→blood) are 7.4 (range: 1.9-37) and 48 (range: 8-408) min, respectively. Median values of half lives of [153Sm]Sm-EDTMP clearance through the urine and of uptake into bone are 1.0 (range: 0.1-6.0) and 1.6 (range: 0.6-9.0) h, respectively.Median value of red marrow absorbed dose is 2.1 (range: 0.7-3.5) Gy and 0.8 (range: 0.3-2.1) Gy/GBq, while median value of bone surface absorbed dose is 11.5 Gy (range: 5.0-18.4) and 4.4 (range: 2.3-14.3) Gy/GBq. It is remarkable that there is a really great biological variability within patients, especially considering the excreted activity. The cumulated activity in bone and red marrow doses were significantly higher in prostate cancer, where metastatic bone lesions are osteoblastic, than in breast cancer where metastatic bone lesions are osteolytic or mixed (lytic/blastic).The relevant biological variability in biodistribution and metabolism of [153Sm]Sm-EDTMP suggests that the fixed administered activity based on patient weight is not sufficient to optimize the treatment and a better optimization would be reached by using a predictive dosimetry tailored to individual patient characteristics. © 2010 Associazione Italiana di Fisica Medica.


PubMed | Ospedale Santobono, CROS NT SRL, Azienda Ospedaliera Universitaria, Azienda Ospedaliera Maggiore della Carita and 6 more.
Type: | Journal: Italian journal of pediatrics | Year: 2015

Invasive diseases (ID) caused by Streptococcus pneumoniae (S. pneumoniae), Haemophilus influenzae (H. influenzae), and Neisseria meningitidis are a major public health problem worldwide. Comprehensive data on the burden of bacteremia and ID in Italy, including data based on molecular techniques, are needed.We conducted a prospective, multi-centre, hospital-based study (GSK study identifier: 111334) to assess the burden of bacteremia and ID among children less than five years old with a fever of 39 C or greater. Study participation involved a single medical examination, collection of blood for polymerase chain reaction (PCR) and blood culture, and collection of an oropharyngeal swab for colonization analysis by PCR.Between May 2008 and June 2009, 4536 patients were screened, 944 were selected and 920 were enrolled in the study. There were 225 clinical diagnoses of ID, 9.8 % (22) of which were bacteremic. A diagnosis of sepsis was made for 38 cases, 5.3 % (2) of which were bacteremic. Among the 629 non-ID diagnoses, 1.6 % (10) were bacteremic. Among the 34 bacteremic cases, the most common diagnoses were community-acquired pneumonia (15/34), pleural effusion (4/34) and meningitis (4/34). S. pneumoniae was the most frequently detected bacteria among bacteremic cases (29/34) followed by H. influenzae (3/34). Ninety percent (27/30) of bacteremic patients with oropharyngeal swab results were colonized with the studied bacterial pathogens compared to 46.1 % (402/872) of non-bacteremic cases (p<0.001). PCV7 (7-valent pneumococcal conjugate vaccine) vaccination was reported for 55.9 % (19/34) of bacteremic cases. S. pneumoniae serotypes were non-vaccine serotypes in children who had been vaccinated. Mean duration of hospitalization was longer for bacteremic cases versus non-bacteremic cases (13.6 versus 5.8 days).These results confirm that S. pneumoniae is one of the pathogens frequently responsible for invasive disease.


Veronese I.,University of Milan | Cantone M.C.,University of Milan | Catalano M.,Instituto Clinico Humanitas | Chiodini N.,University of Milan Bicocca | And 7 more authors.
Journal of Physics D: Applied Physics | Year: 2013

In this study, the spectral emission of Eu3+-doped silica optical fibres is investigated under irradiation with photons and electrons of different energies, field sizes and orientations, in order to discover the origin of stem effect and evaluate its influence on the radioluminescence (RL) spectral shape under experimental conditions. A comparison with previously investigated Ce-doped silica fibres is also made. Below the Cerenkov radiation energy threshold, a slight contribution to the total RL signal is observed. This is due to fluorescence effects occurring in the passive fibre. Above the energy threshold, the stem effect is mainly caused by Cerenkov radiation. A method for removing the stem effect, based on RL spectral analysis, is proposed and validated by measuring the output factors of extended photon fields and by studying the angular dependence of the dosimeter. © 2013 IOP Publishing Ltd.


De Mattia C.,University of Milan | Mones E.,Azienda Ospedaliera Maggiore della Carita | Veronese I.,University of Milan | Fasoli M.,University of Milan Bicocca | And 3 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

The recent progresses in the development and characterization of doped silica fiber optics for dosimetry applications in the modern radiation therapy, and for high energy physics experiments, are presented and discussed. In particular, the main purpose was the production of scintillating fiber optics with an emission spectrum which can be easily and efficiently distinguished from that of other spurious luminescent signals originated in the fiber optic material as consequence of the exposition to ionizing radiations (e.g. Cerenkov light and intrinsic fluorescence phenomena). In addition to the previously investigated dopant (Ce), other rare earth elements (Eu and Yb) were considered for the scintillating fiber optic development. The study of the luminescent and dosimetric properties of these new systems was carried out by using X and gamma rays of different energies and field sizes. © 2014 SPIE.


Veronese I.,University of Milan | Cantone M.C.,University of Milan | Chiodini N.,University of Milan Bicocca | De Mattia C.,University of Milan | And 3 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013

In the last decade, the interest in scintillating fiber optics for ionizing radiation monitoring is constantly increasing. Among the fields of possible applications of these sensors, radiation therapy represents a driving force for the research and development of new devices. In fact, the small dimensions of fiber optics based detectors, together with their realtime response, make these systems extremely promising both in quality assurance measurements of intensity modulated radiotherapy beams, and in in-vivo dosimetry. On the other hand, two specific aspects might represent limiting factors: (i) the stem effect, that is the spurious luminescence originating as a consequence of the irradiation of the light guide, and (ii) the memory effect, that is the radioluminescence sensitivity increase during prolonged exposition to ionizing radiation, typical of many scintillating materials. These two issues, representing the main challenges to face for the effective use of scintillating fiber as dosimeters in radiotherapy, were studied considering amorphous silica matrices prepared by sol-gel method and doped with europium. The origin of the stem effect was investigated by means of spectral measurements of the doped fibers irradiated with Xrays and electrons of different energies, field sizes and orientations. New approaches for removing the stem effect on the basis of the radioluminescent spectral analysis are presented and discussed. Furthermore, the causes and phenomenology of the memory effect are described, considering also the effect of dose accumulation with different dose rates and energies of ionizing radiation. © 2013 SPIE.


Veronese I.,University of Milan | Cantone M.C.,University of Milan | Chiodini N.,University of Milan Bicocca | Fasoli M.,University of Milan Bicocca | And 3 more authors.
Radiation Measurements | Year: 2013

The depth-dose-profile and the transversal beam profile of a 6 MV photon beam are measured by means of Eu-doped silica optical fibres. In both cases, a non-negligible influence of the stem effect was observed as consequence of the change in the relative contribution of the Cerenkov light while varying the vertical and lateral position of the fibre. The approach for removing the spurious luminescence signal based on the radioluminescence (RL) spectral analysis proved to be effective and independent of the irradiation configurations. © 2013 Elsevier B.V. All rights reserved.


De Mattia C.,University of Milan | Veronese I.,University of Milan | Fasoli M.,University of Milan Bicocca | Chiodini N.,University of Milan Bicocca | And 7 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

Rare earths-doped silica optical fibers have shown promising results for ionizing radiation monitoring, thanks to their radio-luminescence (RL) properties. However, the use of these systems for accurate and precise dosimetric measurements in radiation fields above the Cerenkov energy threshold, like those employed in radiation therapy, is still challenging, since a spurious luminescence, namely the "stem effect" is also generated in the passive fiber portion exposed to radiation. The spurious signal mainly occurs in the UV-VIS region, therefore a dopant emitting in the near infrared may be suitable for an optical discrimination of the stem effect. In this work, the RL and dosimetric properties of Yb-doped silica optical fibers, produced by sol-gel technique, are studied, together with the methods and instruments to achieve an efficient optical detection of the Yb3+ emission, characterized by a sharp line at about 975 nm. The results demonstrate that the RL of Yb3+ is free from any spectral superposition with the spurious luminescence. This aspect, in addition with the suitable linearity, reproducibility, and sensitivity properties of the Yb-doped fibers, paves the way to their use in applications where an efficient stem effect removal is required. © 2015 SPIE.


Veronese I.,University of Milan | Mattia C.D.,University of Milan | Fasoli M.,University of Milan Bicocca | Chiodini N.,University of Milan Bicocca | And 3 more authors.
Applied Physics Letters | Year: 2014

Radio-luminescence (RL) optical fiber sensors enable a remote, punctual, and real time detection of ionizing radiation. However, the employment of such systems for monitoring extended radiation fields with energies above the Cerenkov threshold is still challenging, since a spurious luminescence, namely, the "stem effect," is also generated in the passive fiber portion exposed to radiation. Here, we present experimental measurements on Yb-doped silica optical fibers irradiated with photon fields of different energies and sizes. The results demonstrate that the RL of Yb3+, displaying a sharp emission line at about 975 nm, is free from any spectral superposition with the spurious luminescence. This aspect, in addition with the suitable linearity, reproducibility, and sensitivity properties of the Yb-doped fibers, paves the way to their use in applications where an efficient stem effect removal is required. © 2014 AIP Publishing LLC.

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