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Arena, Helene
Universite de Montpellier, 163 Rue Auguste Broussonnet, 34090 Montpellier (France); CEA DEN-DTCD (France)2016
Universite de Montpellier, 163 Rue Auguste Broussonnet, 34090 Montpellier (France); CEA DEN-DTCD (France)2016
AbstractAbstract
[en] This work takes place in the context of the long-term behavior of nuclear glasses under repository conditions. The main objective is to identify, understand and compare the effects of some chemical elements present in the glass composition and/or in the repository media (Zn, Mg, Ni, Co, Fe, Ca, Gd, Ce, K, Cs, Cr and Ag) on the processes involved in glass alteration by water. The cumulative or competitive nature of the effects of these chemical elements was determined. To reach this goal, a 6 oxides simple glass (ISG) has been altered for more than 500 days in a solution containing one or more of the chemical elements of interest. The results indicate that Zn, Mg, Ni, Co and Fe elements increase glass alteration forming secondary phases with the same structure and stoichiometry (tri-octahedral smectites). To form, these silicates consume chemical elements (Si, Al) from the environment and induce a pH decrease until a limiting value of pH. Beyond this pH the precipitation of secondary phases is inhibited and these chemical elements can be integrated into the gel, replacing Ca whose solubility increases at lower pH. As long as they form secondary phases, the effects of these elements are cumulative. Rare earths Gd and Ce also increase glass alteration forming secondary phases but their effects are lower as they contain less silicon. These elements are not integrated in the gel. Chromium increases glass alteration by precipitating with Ca and leading to a less protective gel, depleted in Ca. Silver precipitates as AgCl and has no effect on the alteration of the glass. The chemical elements K, Cs and Ca limit glass alteration by integrating into the gel and slowing down the transport phenomena therein. This integration is competitive: the order of integration (quantity and effectiveness glass alteration limitation) is the following Ca≥≥Cs≥K. Thus, the increase of glass alteration may be proportional to the quantity of elements promoting the precipitation of secondary phases, but the pH decrease limits the process. The effects of the elements that reduce glass alteration by incorporating into the gel are quantitatively limited by the gel composition and its ability to incorporate them, and qualitatively by the nature of the elements. (author)
[fr]
Cette these s'inscrit dans l'etude du comportement a long terme des verres nucleaires en conditions de stockage. Son objectif est de determiner, de comprendre et de comparer les effets de certains elements chimiques presents dans la composition du verre et/ou dans le milieu de stockage (Zn, Mg, Ni, Co, Fe, Ca, Gd, Ce, K, Cs, Cr et Ag) sur les differents processus mis en jeux lors de l'alteration aqueuse des verres nucleaires. Dans ce cadre, une attention particuliere a ete portee sur le caractere cumulatif ou competitif des effets de ces elements. Pour cela, un verre simple a 6 oxydes (ISG) a ete altere pendant plus de 500 jours dans une solution contenant un ou plusieurs des elements chimiques d'interet. Les elements Zn, Mg, Ni, Co et Fe augmentent l'alteration du verre en formant des phases secondaires de meme structure (smectites trioctaedriques) et de meme stoechiometrie (a l'element pres). Leur precipitation consomme des elements chimiques du milieu (Si, Al) et induit une diminution de pH. Ce processus se maintient jusqu'a l'atteinte d'un pH limite propre a chaque phase secondaire, au-dessous duquel leur precipitation est inhibee. Par la suite, ces elements peuvent s'integrer dans le gel d'alteration en remplacement du Ca rendu plus soluble par la baisse du pH. Tant qu'ils forment des phases secondaires, les effets de ces elements sont cumulatifs. Les terres rares Gd et Ce induisent une augmentation de l'alteration du verre en formant des phases secondaires, mais leurs effets sont plus faibles car les phases formees sont moins silicatees. Ces elements ne s'integrent pas dans le gel. Le Cr precipite avec le Ca pour former une phase qui appauvrit le gel en Ca, entraine une diminution du pH et augmente l'alteration du verre. Les elements K, Cs et Ca limitent l'alteration du verre en s'integrant dans le gel et en ralentissant les phenomenes de transport en son sein. Cette integration est competitive: l'ordre d'integration (quantite et efficacite sur la limitation de l'alteration) est le suivant Ca ≥≥ Cs ≥ K. L'element Ag precipitant sous forme d'AgCl, n'a pas d'effet sur l'alteration du verre: cette phase ne modifie ni le milieu, ni le developpement de la pellicule d'alteration. Ainsi, l'augmentation de l'alteration pourrait etre proportionnelle a la quantite d'elements favorisant la precipitation de phases secondaires, mais la diminution de pH qui l'accompagne limite ce processus. Les effets des elements qui diminuent l'alteration du verre en s'incorporant dans le gel, sont limites en quantite par la composition du gel et sa capacite a les recevoir, et en qualite par la nature meme des elementsOriginal Title
Effets cumulatifs et competitifs des elements chimiques sur l'alteration des verres nucleaires
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26 Feb 2016; 253 p; CEA-R--6450; 268 refs.; Available from the INIS Liaison Officer for France, see the 'INIS contacts' section of the INIS website for current contact and E-mail addresses: http://www.iaea.org/inis/Contacts/; Also available from Service commun de documentation Universite de Montpellier Place Eugene Bataillon, Bat 8 - CC 035, 34095 Montpellier Cedex 5 (France); Chimie et Physico-Chimie des Materiaux
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[en] The potential performance of apparent diffusion coefficient (ADC) values for distinguishing malignant and benign pulmonary lesions, further characterizing the subtype of lung cancer was assessed. PubMed, EMBASE, Cochrane Library, EBSCO, and three Chinese databases were searched to identify eligible studies on diffusion-weighted imaging (DWI) of focal pulmonary lesions. ADC values of malignant and benign lesions were extracted by lesion type and statistically pooled based on a linear mixed model. Further analysis for subtype of lung cancer was also performed. The methodological quality was assessed using the quality assessment of diagnostic accuracy studies tool. Thirty-four articles involving 2086 patients were included. Malignant pulmonary lesions have significantly lower ADC values than benign lesions [1.21 (95 % CI, 1.19-1.22) mm"2/s vs. 1.76 (95 % CI, 1.72-1.80) mm"2/s; P < 0.05]. There is a significant difference between ADC values of small cell lung cancer and non-small cell lung cancer (P < 0.05), while the differences were not significant among histological subtypes of lung cancer. The methodological quality was relatively high, and the data points from Begg's test indicated that there was probably no obvious publication bias. The ADC value is helpful for distinguishing malignant and benign pulmonary lesions and provides a promising method for differentiation of SCLC from NSCLC. (orig.)
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Available from: http://dx.doi.org/10.1007/s00330-015-3840-y
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[en] To evaluate whether visual assessment of T2-weighted imaging (T2WI) or an apparent diffusion coefficient (ADC) could predict lymphovascular invasion (LVI) status in cases with clinically node-negative invasive breast cancer. One hundred and thirty-six patients with 136 lesions underwent MRI. Visual assessment of T2WI, tumour-ADC, peritumoral maximum-ADC and the peritumour-tumour ADC ratio (the ratio between them) were compared with LVI status of surgical specimens. No significant relationship was found between LVI and T2WI. Tumour-ADC was significantly lower in the LVI-positive (n = 77, 896 ± 148 x 10"-"6 mm"2/s) than the LVI-negative group (n = 59, 1002 ± 163 x 10"-"6 mm"2/s; p < 0.0001). Peritumoral maximum-ADC was significantly higher in the LVI-positive (1805 ± 355 x 10"-"6 mm"2/s) than the LVI-negative group (1625 ± 346 x 10"-"6 mm"2/s; p = 0.0003). Peritumour-tumour ADC ratio was significantly higher in the LVI-positive (2.05 ± 0.46) than the LVI-negative group (1.65 ± 0.40; p < 0.0001). Receiver operating characteristic curve analysis revealed that the area under the curve (AUC) of the peritumour-tumour ADC ratio was the highest (0.81). The most effective threshold for the peritumour-tumour ADC ratio was 1.84, and the sensitivity, specificity, positive predictive value and negative predictive value were 77 % (59/77), 76 % (45/59), 81 % (59/73) and 71 % (45/63), respectively. We suggest that the peritumour-tumour ADC ratio can assist in predicting LVI status on preoperative imaging. (orig.)
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Available from: http://dx.doi.org/10.1007/s00330-015-3847-4
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No abstract available
Original Title
MRT macht Effekte einer lumbalen Traktion sichtbar
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RoeFo - Fortschritte auf dem Gebiete der Roentgenstrahlen und der Bildgebenden Verfahren; ISSN 1438-9029;
; CODEN RFGNDO; v. 188(1); p. 18

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No abstract available
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Available from: http://dx.doi.org/10.1007/s00259-015-3189-0
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European Journal of Nuclear Medicine and Molecular Imaging; ISSN 1619-7070;
; v. 43(1); p. 5-7

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ALKALINE EARTH ISOTOPES, ALKALINE EARTH METAL COMPOUNDS, ALPHA DECAY RADIOISOTOPES, ANTIMETABOLITES, BETA DECAY RADIOISOTOPES, BETA-PLUS DECAY RADIOISOTOPES, BODY, CARBON 14 DECAY RADIOISOTOPES, CHLORIDES, CHLORINE COMPOUNDS, COMPUTERIZED TOMOGRAPHY, DAYS LIVING RADIOISOTOPES, DIAGNOSTIC TECHNIQUES, DISEASES, DRUGS, EMISSION COMPUTED TOMOGRAPHY, EVEN-ODD NUCLEI, FLUORINE ISOTOPES, GLANDS, HALIDES, HALOGEN COMPOUNDS, HEAVY ION DECAY RADIOISOTOPES, HEAVY NUCLEI, HOURS LIVING RADIOISOTOPES, ISOMERIC TRANSITION ISOTOPES, ISOTOPES, LABELLED COMPOUNDS, LIGHT NUCLEI, MALE GENITALS, MATERIALS, MEDICINE, NANOSECONDS LIVING RADIOISOTOPES, NEOPLASMS, NUCLEAR MEDICINE, NUCLEI, ODD-ODD NUCLEI, ORGANS, RADIOACTIVE MATERIALS, RADIOISOTOPES, RADIOLOGY, RADIUM COMPOUNDS, RADIUM HALIDES, RADIUM ISOTOPES, THERAPY, TOMOGRAPHY
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[en] Definitive radiotherapy and vismodegib, an oral inhibitor of the hedgehog pathway, are both established treatment options for locally advanced basal cell carcinomas (BCC). Both have shown good results in local tumor control; however, the effects concerning advanced tumors are often not of a lasting nature and to date no systematic data about the combination of the two modalities are available. We retrospectively analyzed four patients who received vismodegib and radiotherapy in combination. Radiation doses varied between 50.4 Gy and 66.0 Gy. Three patients had recurrent BCC. One patient had locoregional lymph node involvement. Vismodegib was taken once a day (150 mg) during the entire time of irradiation and beyond upon instructions of the attending dermatologist. In three cases a persistent complete response was observed, in one case the tumor remained stable for approximately 6 months until further tumor progression was documented. The combined therapy was well tolerated in all cases. No exceptional side effects pointing at a drug-radiation interaction were observed. The combination of vismodegib and radiation seems feasible and the initial results are promising. In our cohort, there was no increase in unexpected side effects. Further research is needed to evaluate the significance of this combined therapy. (orig.)
[de]
Sowohl definitive Radiotherapie als auch Vismodegib, ein oraler Inhibitor der Hedgehog-Signalkaskade, sind etablierte Behandlungsoptionen fuer lokal fortgeschrittene Basalzellkarzinome (BCC). Beide Therapien zeigen fuer sich gute Ansprechraten, aber die lokale Tumorkontrolle ist oft nicht dauerhaft und bis heute existieren kaum Daten ueber eine Kombination der beiden Modalitaeten. Wir analysierten retrospektiv vier Patientenfaelle nach simultaner Applikation von Vismodegib und Bestrahlung. Die Bestrahlungsdosis variierte zwischen 50,4 Gy und 66,0 Gy. Drei der Patienten hatten ein rezidiviertes BCC. Ein Patient hatte einen befallenen regionalen Lymphknoten. Vismodegib wurde einmal taeglich (150 mg) ueber die gesamte Radiotherapie und nach deren Beendigung, je nach Empfehlung des betreuenden Dermatologen, eingenommen. In drei Faellen konnte ein laenger andauerndes Ansprechen beobachtet werden. In einem Fall verblieb der Tumor fuer 6 Monate stabil, bevor eine erneute Tumorprogression festgestellt werden konnte. Die kombinierte Therapie wurde in allen Faellen gut vertragen. Es konnten keine unerwarteten Nebenwirkungen beobachtet werden, die auf eine supraadditive Toxizitaet deuten koennten. Die Kombination von Vismodegib und Radiotherapie erscheint moeglich. Die ersten Ergebnisse sind vielversprechend. In unserer Kohorte konnte keine erhoehte Toxizitaet beobachtet werden. Kuenftige Studien sollten den Stellenwert dieser kombinierten Therapie untersuchen. (orig.)Primary Subject
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Available from: http://dx.doi.org/10.1007/s00066-015-0902-7
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ABSORBED DOSE RANGE, ANIMAL TISSUES, BEAMS, BIOLOGICAL EFFECTS, BIOLOGICAL RADIATION EFFECTS, BODY, DERMATITIS, DIAGNOSTIC TECHNIQUES, DISEASES, EPITHELIUM, GY RANGE, INJURIES, IRRADIATION, LEPTON BEAMS, LOCAL RADIATION EFFECTS, LYMPHATIC SYSTEM, MEDICINE, NEOPLASMS, NUCLEAR MEDICINE, ORGANS, PARTICLE BEAMS, RADIATION DOSE RANGES, RADIATION EFFECTS, RADIATION INJURIES, RADIOLOGY, RADIOTHERAPY, SKIN, SKIN DISEASES, THERAPY, TOMOGRAPHY
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[en] To examine the anatomic MRI characteristics of the adductor magnus mini hamstring (AMMH) and explore its involvement in cases of hamstring avulsion. An IRB-approved retrospective review of patients undergoing ''hamstring protocol'' MRI between March 2009 and June 2014 was performed. Two musculoskeletal radiologists recorded multiple AMMH anatomic characteristics and involvement in cases of hamstring avulsion. Seventy-six AMMHs were analyzed in 66 patients [35 females and 31 males, mean age 49.3 ± 15.2 years (range 17-81)]. Eleven percent of AMMHs were poorly visualized, 51 % visualized, and 37 % well visualized. Seven percent demonstrated round, 73 % ovoid, and 21 % flat/lenticular tendon morphologies. Most (88 %) demonstrated typical origins. Average cross-sectional area (CSA) was 22.4 ± 10.6 mm"2 (range 6-56), diameter was 7.2 ± 2.5 mm (range 2.9-15), medial distance from the semimembranosus tendon was 7.5 ± 2.5 mm (range 3-14), and tendon length was 6.8 ± 3.3 cm (range 1.2-14.1). There was no gender difference in AMMH anatomic measurements or correlation between age and CSA or diameter. Of 17 complete hamstring avulsion cases, the AMMH was intact in 13, partially torn in 3, and completely torn in 1. The AMMH is a constant finding with variable anatomic characteristics. It is visualized or well visualized by MRI in 88 % of cases and is a sizable tendon located in close proximity to the semimembranosus tendon. Because it is uncommonly completely torn (6 %) in cases of complete hamstring avulsion, radiologists should be aware of its presence and appearance to avoid diagnostic confusion. (orig.)
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Available from: http://dx.doi.org/10.1007/s00256-015-2291-5
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[en] The purpose was to investigate the diagnostic performance of different combinations of anatomical and functional imaging techniques in PET/MRI and PET/CT for the evaluation of metastatic colorectal cancer lesions. Image data of 15 colorectal cancer patients (FDG-PET/CT and subsequent FDG-PET/MRI) were retrospectively evaluated by two readers in five reading sessions: MRI (morphology) alone, MRI/diffusion-weighted MRI (DWI), MRI/PET, MRI/DWI/PET; and PET/CT. Diagnostic performance of lesion detection with each combination was assessed in general and organ-based. The reference standard was given by histology and/or follow-up imaging. Separate analysis of mucinous tumours was performed. One hundred and eighty lesions (110 malignant) were evaluated (intestine n = 6, liver n = 37, lymph nodes n = 55, lung n = 4, and peritoneal n = 74). The overall lesion-based diagnostic accuracy was 0.46 for MRI, 0.47 for MRI/DWI, 0.57 for MRI/PET, 0.69 for MRI/DWI/PET and 0.66 for PET/CT. In the organ-based assessment, MRI/DWI/PET showed the highest accuracy for liver metastases (0.74), a comparable accuracy to PET/CT in peritoneal lesions (0.55), and in lymph node metastases (0.84). The accuracy in mucinous tumour lesions was limited in all modalities (MRI/DWI/PET = 0.52). PET/MRI including DWI is comparable to PET/CT in the evaluation of colorectal cancer metastases, with a markedly higher accuracy when using combined imaging data than the modalities separately. Further improvement is needed in the imaging of peritoneal carcinomatosis and mucinous tumours. (orig.)
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Available from: http://dx.doi.org/10.1007/s00259-015-3137-z
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European Journal of Nuclear Medicine and Molecular Imaging; ISSN 1619-7070;
; v. 43(1); p. 123-132

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ANTIMETABOLITES, BETA DECAY RADIOISOTOPES, BETA-PLUS DECAY RADIOISOTOPES, BODY, COMPUTERIZED TOMOGRAPHY, DIAGNOSTIC TECHNIQUES, DIGESTIVE SYSTEM, DISEASES, DRUGS, EMISSION COMPUTED TOMOGRAPHY, FLUORINE ISOTOPES, FUNCTIONS, GASTROINTESTINAL TRACT, GLANDS, HOURS LIVING RADIOISOTOPES, INTESTINES, ISOMERIC TRANSITION ISOTOPES, ISOTOPES, LABELLED COMPOUNDS, LARGE INTESTINE, LIGHT NUCLEI, LYMPHATIC SYSTEM, MATERIALS, MEDICINE, NANOSECONDS LIVING RADIOISOTOPES, NEOPLASMS, NUCLEI, ODD-ODD NUCLEI, ORGANS, PROCESSING, RADIOACTIVE MATERIALS, RADIOISOTOPES, THERAPY, TOMOGRAPHY
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[en] To observe the distribution and potential distribution patterns of osteolytic and sclerotic vertebral involvement in a representative collective of multiple myeloma patients. A total of 66 consecutive patients with a diagnosis of multiple myeloma at initial diagnosis or during follow-up were examined by multidetector reduced-dose computed tomography to evaluate the distribution of bone lesions along the spine with focus on size, location, and lesion character. Confirmation of diagnosis was performed by comparison to follow-up computed tomography or magnetic resonance tomography. If >50 % of all detected malignant lesions occurred in one spinal segment, the distribution pattern was called cervical, thoracic, lumbar, or sacral, otherwise a ''mixed'' pattern was classified. Of a total number of 933 osseous spine lesions, 632 (67.7 %) were classified as malignant (98.9 % of them osteolytic) and 293 (31.5 %) as benign. The distribution pattern analysis yielded two patients (3.8 %) with a cervical, 26 (50 %) with a thoracic, 4 (7.7 %) with a lumbar, one (1.9 %) with a sacral pattern, and 19 cases (36.6 %) showed a mixed distribution pattern. Segment-wise, the mean lesion size was 6.52 ± 2.76 mm (cervical), 8.97 ± 5.43 mm (thoracic), 11.97 ± 7.11 mm (lumbar), and 17.5 ± 16.465 (sacral), whilst, related to the vertebra size, the lesion/vertebra size ratio is decreasing through the whole spine beginning from the top. Multiple myeloma bone lesions occur preferably and are larger in the thoracic and lumbar spine. Moreover, a specific distribution pattern is present in about 60 %. (orig.)
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Available from: http://dx.doi.org/10.1007/s00256-015-2268-4
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[en] The objective of this study was to investigate the common sites of subchondral insufficiency fractures of the femoral head (SIF) based on three-dimensional (3-D) reconstruction of MR images. In 33 hips of 31 consecutive patients diagnosed with SIF, 3-D reconstruction of the bone, fracture, and acetabular edge was performed using MR images. These 3-D images were used to measure the fractured areas and clarify the positional relationship between the fracture and degree of acetabular coverage. The fractured area in the anterior portion was significantly larger than in the posterior area. In 11 cases, the fractures contacted the acetabular edge and were distributed on the lateral portion. The indices of acetabular coverage (center-edge angle and acetabular head index) in these cases were less than the normal range. In the remaining 22 cases, the fractures were apart from the acetabular edge and distributed on the mediolateral centerline of the femoral head. The majority of these cases had normal acetabular coverage. The common site of SIF is the anterior portion. In addition, two types of SIF are proposed: (1) Lateral type: the contact stress between the acetabular edge and lateral portion of the femoral head causes SIF based on the insufficient acetabular coverage, and (2) Central type: the contact stress between the acetabular surface and the mediolateral center of the femoral head causes SIF independent from the insufficiency of acetabular coverage. These findings may be useful for considering the treatment and prevention of SIF. (orig.)
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Available from: http://dx.doi.org/10.1007/s00256-015-2258-6
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