184 resultados para 3-PHASE JUNCTION


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OBJECTIVE: The objective of this study was to analyse the long-term mortality and morbidity of a group of patients undergoing thrombolysis during the acute phase of myocardial infarction and to determine the factors influencing the prognosis. One hundred and seventy five patients (149 mean and 26 women, mean age: 54 years) were included in a randomized study, comparing the efficacy of 2 thrombolytic substances administered during the acute phase of myocardial infarction. A standard questionnaire was sent to the various attending physicians to follow-up of these 175 patients. RESULTS: The hospital mortality was 5% (9 patients) and 14 patients (9%) died after a mean follow-up of 4.3 +/- 2.1 years. The 5-year actuarial survival was 81%. Fourteen patients (8%) were lost to follow-up and 49 patients (32%) underwent surgical or percutaneous revascularization during follow-up. Revascularized patients had a significantly better survival than non-revascularized patients. The mean left ventricular ejection fraction of patients who died was lower (48% versus 71%) than that of survivors. Patients with an ejection fraction < 40% also had a significantly lower survival (p = 0.01). Patency of the vessel after thrombolysis was associated with a slightly better survival; this difference was not significant. The ejection fraction at 6 month was also significantly higher (60 +/- 10% versus 49 +/- 11%) for patients with a patent artery. Three risk factors for death or reinfarction were identified: age > 65 years at the time of infarction, disease in more than one coronary vessel and absence of angina pectoris before infarction. The probability of a coronary accident varied from 2 to 88% according to the number of risk factors present. At the time of follow-up, 60% of patients presented hypercholesterolaemia versus only 7% before infarction 73% of patients received anticoagulant or antiaggregant treatment and 81% of patients were asymptomatic. CONCLUSION: The mortality and the acute and long-term morbidity of myocardial infarction remain high, as only 34% of our patients did not develop any events during follow-up, despite serious medical management and follow-up. The ejection fraction has an important prognostic value. Patient management should take the abovementioned risk factors into account.

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Les problèmes d'écoulements multiphasiques en média poreux sont d'un grand intérêt pour de nombreuses applications scientifiques et techniques ; comme la séquestration de C02, l'extraction de pétrole et la dépollution des aquifères. La complexité intrinsèque des systèmes multiphasiques et l'hétérogénéité des formations géologiques sur des échelles multiples représentent un challenge majeur pour comprendre et modéliser les déplacements immiscibles dans les milieux poreux. Les descriptions à l'échelle supérieure basées sur la généralisation de l'équation de Darcy sont largement utilisées, mais ces méthodes sont sujettes à limitations pour les écoulements présentant de l'hystérèse. Les avancées récentes en terme de performances computationnelles et le développement de méthodes précises pour caractériser l'espace interstitiel ainsi que la distribution des phases ont favorisé l'utilisation de modèles qui permettent une résolution fine à l'échelle du pore. Ces modèles offrent un aperçu des caractéristiques de l'écoulement qui ne peuvent pas être facilement observées en laboratoire et peuvent être utilisé pour expliquer la différence entre les processus physiques et les modèles à l'échelle macroscopique existants. L'objet premier de la thèse se porte sur la simulation numérique directe : les équations de Navier-Stokes sont résolues dans l'espace interstitiel et la méthode du volume de fluide (VOF) est employée pour suivre l'évolution de l'interface. Dans VOF, la distribution des phases est décrite par une fonction fluide pour l'ensemble du domaine et des conditions aux bords particulières permettent la prise en compte des propriétés de mouillage du milieu poreux. Dans la première partie de la thèse, nous simulons le drainage dans une cellule Hele-Shaw 2D avec des obstacles cylindriques. Nous montrons que l'approche proposée est applicable même pour des ratios de densité et de viscosité très importants et permet de modéliser la transition entre déplacement stable et digitation visqueuse. Nous intéressons ensuite à l'interprétation de la pression capillaire à l'échelle macroscopique. Nous montrons que les techniques basées sur la moyenne spatiale de la pression présentent plusieurs limitations et sont imprécises en présence d'effets visqueux et de piégeage. Au contraire, une définition basée sur l'énergie permet de séparer les contributions capillaires des effets visqueux. La seconde partie de la thèse est consacrée à l'investigation des effets d'inertie associés aux reconfigurations irréversibles du ménisque causé par l'interface des instabilités. Comme prototype pour ces phénomènes, nous étudions d'abord la dynamique d'un ménisque dans un pore angulaire. Nous montrons que, dans un réseau de pores cubiques, les sauts et reconfigurations sont si fréquents que les effets d'inertie mènent à différentes configurations des fluides. A cause de la non-linéarité du problème, la distribution des fluides influence le travail des forces de pression, qui, à son tour, provoque une chute de pression dans la loi de Darcy. Cela suggère que ces phénomènes devraient être pris en compte lorsque que l'on décrit l'écoulement multiphasique en média poreux à l'échelle macroscopique. La dernière partie de la thèse s'attache à démontrer la validité de notre approche par une comparaison avec des expériences en laboratoire : un drainage instable dans un milieu poreux quasi 2D (une cellule Hele-Shaw avec des obstacles cylindriques). Plusieurs simulations sont tournées sous différentes conditions aux bords et en utilisant différents modèles (modèle intégré 2D et modèle 3D) afin de comparer certaines quantités macroscopiques avec les observations au laboratoire correspondantes. Malgré le challenge de modéliser des déplacements instables, où, par définition, de petites perturbations peuvent grandir sans fin, notre approche numérique apporte de résultats satisfaisants pour tous les cas étudiés. - Problems involving multiphase flow in porous media are of great interest in many scientific and engineering applications including Carbon Capture and Storage, oil recovery and groundwater remediation. The intrinsic complexity of multiphase systems and the multi scale heterogeneity of geological formations represent the major challenges to understand and model immiscible displacement in porous media. Upscaled descriptions based on generalization of Darcy's law are widely used, but they are subject to several limitations for flow that exhibit hysteric and history- dependent behaviors. Recent advances in high performance computing and the development of accurate methods to characterize pore space and phase distribution have fostered the use of models that allow sub-pore resolution. These models provide an insight on flow characteristics that cannot be easily achieved by laboratory experiments and can be used to explain the gap between physical processes and existing macro-scale models. We focus on direct numerical simulations: we solve the Navier-Stokes equations for mass and momentum conservation in the pore space and employ the Volume Of Fluid (VOF) method to track the evolution of the interface. In the VOF the distribution of the phases is described by a fluid function (whole-domain formulation) and special boundary conditions account for the wetting properties of the porous medium. In the first part of this thesis we simulate drainage in a 2-D Hele-Shaw cell filled with cylindrical obstacles. We show that the proposed approach can handle very large density and viscosity ratios and it is able to model the transition from stable displacement to viscous fingering. We then focus on the interpretation of the macroscopic capillary pressure showing that pressure average techniques are subject to several limitations and they are not accurate in presence of viscous effects and trapping. On the contrary an energy-based definition allows separating viscous and capillary contributions. In the second part of the thesis we investigate inertia effects associated with abrupt and irreversible reconfigurations of the menisci caused by interface instabilities. As a prototype of these phenomena we first consider the dynamics of a meniscus in an angular pore. We show that in a network of cubic pores, jumps and reconfigurations are so frequent that inertia effects lead to different fluid configurations. Due to the non-linearity of the problem, the distribution of the fluids influences the work done by pressure forces, which is in turn related to the pressure drop in Darcy's law. This suggests that these phenomena should be taken into account when upscaling multiphase flow in porous media. The last part of the thesis is devoted to proving the accuracy of the numerical approach by validation with experiments of unstable primary drainage in a quasi-2D porous medium (i.e., Hele-Shaw cell filled with cylindrical obstacles). We perform simulations under different boundary conditions and using different models (2-D integrated and full 3-D) and we compare several macroscopic quantities with the corresponding experiment. Despite the intrinsic challenges of modeling unstable displacement, where by definition small perturbations can grow without bounds, the numerical method gives satisfactory results for all the cases studied.

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PURPOSE: We conducted a phase I multicenter trial in naïve metastatic castrate-resistant prostate cancer patients with escalating inecalcitol dosages, combined with docetaxel-based chemotherapy. Inecalcitol is a novel vitamin D receptor agonist with higher antiproliferative effects and a 100-fold lower hypercalcemic activity than calcitriol. EXPERIMENTAL DESIGN: Safety and efficacy were evaluated in groups of three to six patients receiving inecalcitol during a 21-day cycle in combination with docetaxel (75 mg/m2 every 3 weeks) and oral prednisone (5 mg twice a day) up to six cycles. Primary endpoint was dose-limiting toxicity (DLT) defined as grade 3 hypercalcemia within the first cycle. Efficacy endpoint was ≥30% PSA decline within 3 months. RESULTS: Eight dose levels (40-8,000 μg) were evaluated in 54 patients. DLT occurred in two of four patients receiving 8,000 μg/day after one and two weeks of inecalcitol. Calcemia normalized a few days after interruption of inecalcitol. Two other patients reached grade 2, and the dose level was reduced to 4,000 μg. After dose reduction, calcemia remained within normal range and grade 1 hypercalcemia. The maximum tolerated dose was 4,000 μg daily. Respectively, 85% and 76% of the patients had ≥30% PSA decline within 3 months and ≥50% PSA decline at any time during the study. Median time to PSA progression was 169 days. CONCLUSION: High antiproliferative daily inecalcitol dose has been safely used in combination with docetaxel and shows encouraging PSA response (≥30% PSA response: 85%; ≥50% PSA response: 76%). A randomized phase II study is planned.

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Impressive developments in X-ray imaging are associated with X-ray phase contrast computed tomography based on grating interferometry, a technique that provides increased contrast compared with conventional absorption-based imaging. A new "single-step" method capable of separating phase information from other contributions has been recently proposed. This approach not only simplifies data-acquisition procedures, but, compared with the existing phase step approach, significantly reduces the dose delivered to a sample. However, the image reconstruction procedure is more demanding than for traditional methods and new algorithms have to be developed to take advantage of the "single-step" method. In the work discussed in this paper, a fast iterative image reconstruction method named OSEM (ordered subsets expectation maximization) was applied to experimental data to evaluate its performance and range of applicability. The OSEM algorithm with different subsets was also characterized by comparison of reconstruction image quality and convergence speed. Computer simulations and experimental results confirm the reliability of this new algorithm for phase-contrast computed tomography applications. Compared with the traditional filtered back projection algorithm, in particular in the presence of a noisy acquisition, it furnishes better images at a higher spatial resolution and with lower noise. We emphasize that the method is highly compatible with future X-ray phase contrast imaging clinical applications.

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Background: Single agent DTIC is the standard therapy for metastatic melanoma (MM) with response rates of 5−20%. Temozolomide (Tem) as an oral drug has shown equal efficacy in phase III trials. Preclinical models have shown an inhibitory effect for bevacizumab (Bev) on the proliferation of melanoma cells as well as on sprouting endothelial cells. Therefore, a therapeutic approach that combines angiogenesis inhibitors with cytotoxic agents may provide clinical benefit in MM. Methods: Design: Multicenter phase II trial. Primary endpoint: Clinical benefit (CR, PR and SD) at 12 weeks; secondary endpoints: best overall response by RECIST, response duration, progression free survival, adverse events, survival after 6 months and overall survival. Sample size was calculated according to Simon's two stage optimal design (5% significance level and 80% power) with an overall sample size of 62 patients (pts) to test H0: 20% versus H1: 35% rate of clinical benefit. Response assessment was done every 6 weeks (3 cycles). Eligibility: Stage IV MM, ECOG PS 0−2, no prior treatment for metastatic disease. Treatment regimen: One cycle consisted of Tem at 150 mg/m2 days 1−7 po and Bev at 10 mg/kg day 1 over 30 min iv and was repeated every 2 weeks until progression or unacceptable toxicity. Results: Between January 2008 and April 2009, 62 pts (40 male/22 female) at a median age of 61 years (range 30−86) with stage IV (M1a:4, M1b:12, M1c:46) melanoma were enrolled in 9 centers. The first 50 pts, who received 415 cycles are included in this interim report. The overall response rate was 26% (CR: 1 pt, PR: 12 pts; PR not confirmed yet in 3 pts), and 44% (22 pts) had stable disease over 1.5−7.5 months (median: 3). Only 30% (15 pts) had disease progression at the first evaluation at week 6. The hematological grade 3/4 toxicities according to NCI CTAE 3.0 were thrombocytopenia 10% (5 pts), neutropenia 8% (4 pts), lymphopenia and leucocytopenia each 2% (1 pt). Cumulative non-hematological toxicities grade 3/4 were nausea and fatigue each 6% (3 pts), hypertension, vomiting and hemorrhage, each 4% (2 pts), thrombosis/embolism, infection, constipation, anorexia, elevation of alkaline phosphatase, bilirubin, GGT, ALT and AST each 2% (1 pt). Conclusion: In metastatic melanoma the combination of Tem/Bev is a safe regimen with a promising efficacy and few grade 3/4 toxicities. Updated results of all 62 pts will be presented.

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The aim was to investigate the efficacy of neoadjuvant docetaxel-cisplatin and identify prognostic factors for outcome in locally advanced stage IIIA (pN2 by mediastinoscopy) non-small-cell lung cancer (NSCLC) patients. In all, 75 patients (from 90 enrolled) underwent tumour resection after three 3-week cycles of docetaxel 85 mg m-2 (day 1) plus cisplatin 40 or 50 mg m-2 (days 1 and 2). Therapy was well tolerated (overall grade 3 toxicity occurred in 48% patients; no grade 4 nonhaematological toxicity was reported), with no observed late toxicities. Median overall survival (OS) and event-free survival (EFS) times were 35 and 15 months, respectively, in the 75 patients who underwent surgery; corresponding figures for all 90 patients enrolled were 28 and 12 months. At 3 years after initiating trial therapy, 27 out of 75 patients (36%) were alive and tumour free. At 5-year follow-up, 60 and 65% of patients had local relapse and distant metastases, respectively. The most common sites of distant metastases were the lung (24%) and brain (17%). Factors associated with OS, EFS and risk of local relapse and distant metastases were complete tumour resection and chemotherapy activity (clinical response, pathologic response, mediastinal downstaging). Neoadjuvant docetaxel-cisplatin was effective and tolerable in stage IIIA pN2 NSCLC, with chemotherapy contributing significantly to outcomes.

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Recent immunotherapy trials have shown that lymphodepletion induced by short-term chemotherapy favors subsequent expansion of adoptively transferred T cells, by homeostatic mechanisms. To take advantage of this effect, novel regimens are being developed with the aim to enhance tumor immunity and reduce treatment toxicity. We have designed a clinical phase I trial combining chemotherapy, reinfusion of PBMC containing Melan-A(MART-1)-specific T cells, and vaccination with Melan-A peptide in Incomplete Freund's Adjuvant. Treatment with Busulfan plus Fludarabine depleted lymphocytes only weakly. Cyclophosphamide (CTX) plus Fludarabine depleted lymphocytes more profoundly, with a maximal effect using high doses of CTX. It is interesting to note that, the degree of homeostatic T-cell proliferation correlated tightly with the extent of lymphodepletion. As compared with CD4 T cells, CD8 T cells showed higher susceptibility to chemotherapy, followed by more rapid homeostatic proliferation and recovery, resulting in strong inversions of CD4/CD8 ratios. Despite efficient homeostatic proliferation of total CD4 and CD8 T cells, the frequency of CD8 T cells specific for Melan-A and cancer-testis antigens remained relatively low. In contrast, EBV-specific T cells expanded and reached high numbers. We conclude that short-term chemotherapy promoted homeostatic lymphocyte proliferation depending on the intensity of lymphocyte depletion, however without preferential expansion of tumor antigen-specific T cells.

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OBJECTIVE: The aim of the current study was to investigate the biomechanical stability and fixation strength provided by a posterior approach reconstruction technique to realign the craniovertebral junction.¦METHODS: We tested seven human cadaver occipito-cervical spines (occiput-C4) by applying pure moments of ±1.5 Nm on a spine tester. Each specimen was tested in the following modes: 1) intact; 2) injured; 3) spacers alone at C1-C2 articulation (S); 4) spacers plus C1-C2 Posterior Instrumentation (S+PI); and 5) spacers plus C1-C2 posterior instrumentation plus midline wiring (S+PI+MLW). C1-C2 range of motion for each construct was obtained in flexion-extension, lateral bending, and axial rotation.¦RESULTS: In all the loading modes, S, S+PI, and S+PI+MLW constructs significantly reduced range of motion compared with the intact and injured condition (P < 0.05). There was no statistical difference between any of the three instrumentation constructs (P > 0.05).¦CONCLUSIONS: This study investigated the biomechanics of the posterior approach technique for realignment of the craniovertebral junction and also made comparisons with additional posterior fixations. The stand-alone spacers were stable in all three loading modes. Posterior instrumentation increased the stability as compared to stand-alone spacers. The third point of fixation, carried out by using midline wiring, increased the stability further. However, there was not much difference in the stability imparted with the midline wiring versus without. The present study highlights the biomechanics of this novel concept and reaffirms the view that distraction of the C1-C2 articular facets and direct articular joint atlantoaxial fixation would be an ideal method of management of basilar invagination.

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PURPOSE: Recurrent head and neck cancer is associated to a poor survival prognosis. A high toxicity rate is demonstrated when surgery and/or radiotherapy and/or chemotherapy are combined. Furthermore, the duration of treatment is often not ethically compatible with the expected survival (median survival<1year). Normal tissues tolerance limits the use of reirradiation and stereotactic body radiotherapy (SBRT) could offer precise irradiation while sparing healthy tissues. After completion of a feasibility study, results of a multicentric study (Lille, Nancy & Nice) using SBRT with cetuximab are reported. The aim of the study was to deliver non toxic short course SBRT (2weeks) in order to get the same local control as the one demonstrated with longer protocols. METHODS AND MATERIALS: Patients with inoperable recurrent, or new primary tumor in a previously irradiated area, were included (WHO<3). Reirradiation (RT) dose was 36Gy in six fractions of 6Gy to the 85% isodose line covering 95% of the PTV with 5 injections of concomitant cetuximab (CT). All patients had previous radiotherapy, 85% had previous surgery and 48% previous chemotherapy. RESULTS: Between 11/2007 and 08/2010, 60 were included (46 men and 14 women), 56 received CT+RT, 3 were not treated and 1 received only CT. Median age was 60 (42-87)) and all 56 patients had squamous carcinoma and received concomitant cetuximab. Mean time between previous radiotherapy and the start of SBRT was 38months. Cutaneous toxicity was observed for 41 patients. There was one toxic death from hemorrhage and denutrition. Median follow-up was 11.4months. At 3months, response rate was 58.4% (95% CI: 43.2-72.4%) and disease control rate was 91.7% (95% CI: 80.0-97.7%). The one-year OS rate was 47.5% (95% CI: 30.8-62.4). CONCLUSION: These results suggest that short SBRT with cetuximab is an effective salvage treatment with good response rate in this poor prognosis population with previously irradiated HNC. Treatment is feasible and, with appropriate care to limiting critical structure, acute toxicities are acceptable. This combination may be the reference treatment is this population.

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BACKGROUND: Letrozole radiosensitises breast cancer cells in vitro. In clinical settings, no data exist for the combination of letrozole and radiotherapy. We assessed concurrent and sequential radiotherapy and letrozole in the adjuvant setting. METHODS: This phase 2 randomised trial was undertaken in two centres in France and one in Switzerland between Jan 12, 2005, and Feb 21, 2007. 150 postmenopausal women with early-stage breast cancer were randomly assigned after conserving surgery to either concurrent radiotherapy and letrozole (n=75) or sequential radiotherapy and letrozole (n=75). Randomisation was open label with a minimisation technique, stratified by investigational centres, chemotherapy (yes vs no), radiation boost (yes vs no), and value of radiation-induced lymphocyte apoptosis (< or = 16% vs >16%). Whole breast was irradiated to a total dose of 50 Gy in 25 fractions over 5 weeks. In the case of supraclavicular and internal mammary node irradiation, the dose was 44-50 Gy. Letrozole was administered orally once daily at a dose of 2.5 mg for 5 years (beginning 3 weeks pre-radiotherapy in the concomitant group, and 3 weeks post-radiotherapy in the sequential group). The primary endpoint was the occurrence of acute (during and within 6 weeks of radiotherapy) and late (within 2 years) radiation-induced grade 2 or worse toxic effects of the skin. Analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00208273. FINDINGS: All patients were analysed apart from one in the concurrent group who withdrew consent before any treatment. During radiotherapy and within the first 12 weeks after radiotherapy, 31 patients in the concurrent group and 31 in the sequential group had any grade 2 or worse skin-related toxicity. The most common skin-related adverse event was dermatitis: four patients in the concurrent group and six in the sequential group had grade 3 acute skin dermatitis during radiotherapy. At a median follow-up of 26 months (range 3-40), two patients in each group had grade 2 or worse late effects (both radiation-induced subcutaneous fibrosis). INTERPRETATION: Letrozole can be safely delivered shortly after surgery and concomitantly with radiotherapy. Long-term follow-up is needed to investigate cardiac side-effects and cancer-specific outcomes. FUNDING: Novartis Oncology France.

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Cases of fatal outcome after surgical intervention are autopsied to determine the cause of death and to investigate whether medical error caused or contributed to the death. For medico-legal purposes, it is imperative that autopsy findings are documented clearly. Modern imaging techniques such as multi-detector computed tomography (MDCT) and postmortem CT angiography, which is used for vascular system imaging, are useful tools for determining cause of death. The aim of this study was to determine the utility of postmortem CT angiography for the medico-legal death investigation. This study investigated 10 medico-legal cases with a fatal outcome after surgical intervention using multi-phase postmortem whole body CT angiography. A native CT scan was performed as well as three angiographic phases (arterial, venous, and dynamic) using a Virtangio((R)) perfusion device and the oily contrast agent, Angiofil((R)). The results of conventional autopsy were compared to those from the radiological investigations. We also investigated whether the radiological findings affected the final interpretation of cause-of-death. Causes of death were hemorrhagic shock, intracerebral hemorrhage, septic shock, and a combination of hemorrhage and blood aspiration. The diagnoses were made by conventional autopsy as well as by postmortem CT angiography. Hemorrhage played an important role in eight of ten cases. The radiological exam revealed the exact source of bleeding in seven of the eight cases, whereas conventional autopsy localized the source of bleeding only generally in five of the seven cases. In one case, neither conventional autopsy nor CT angiography identified the source of hemorrhage. We conclude that postmortem CT angiography is extremely useful for investigating deaths following surgical interventions. This technique helps document autopsy findings and allows a second examination if it is needed; specifically, it detects and visualizes the sources of hemorrhages in detail, which is often of particular interest in such cases.

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The Breast International Group (BIG) 1-98 study is a four-arm trial comparing 5 years of monotherapy with tamoxifen or with letrozole or with sequences of 2 years of one followed by 3 years of the other for postmenopausal women with endocrine-responsive early invasive breast cancer. From 1998 to 2003, BIG -98 enrolled 8,010 women. The enhanced design f the trial enabled two complementary analyses of efficacy and safety. Collection of tumor specimens further enabled treatment comparisons based on tumor biology. Reports of BIG 1-98 should be interpreted in relation to each individual patient as she weighs the costs and benefits of available treatments. Clinicaltrials.gov ID: NCT00004205.

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PURPOSE: The benefit of surgery on renal function in unilateral ureteropelvic junction stenosis (UPJS) is still debated. We evaluated renal function outcome after unilateral pyeloplasty in 53 children. MATERIALS AND METHODS: We retrospectively reviewed 123I-hippuran renography performed at diagnosis and 5 to 15 years (mean +/- SD 7 +/- 3 years) after successful pyeloplasty. UPJS was prenatally detected in 26 children because of urinary tract infection in 17 and miscellaneous reasons in 10. Relative function (RF) and absolute function were measured on background corrected renograms. Absolute function of the affected and contralateral kidneys was determined by an accumulation index (AI), representing the percent injected dose extracted by each kidney 30 to 90 seconds after the heart peak. RESULTS: Preoperatively 33 of the 53 UPJS kidneys had a decreased AI but only 8 had a RF of less than 40%, which was improved in 7 at followup. In addition, the AI improved in 29 kidneys, of which 19 (36%) normalized. Of the UPJS kidneys 14 had an initially decreased AI that remained abnormal at followup. In these kidneys preoperative RF was less than 40% in all. At followup RF was greater than 40% in 4 children, in whom the AI of the UPJS kidney did not improve but the AI of the contralateral one decreased from supranormal to normal. Seven contralateral kidneys had a supranormal AI, whereas the AI remained normal in 3, of which the RF in the UPJS kidney remained at less than 40%. The AI and RF were normal in 20 UPJS kidneys and remained normal. CONCLUSIONS: When normal, the AI and RF reflected renal function outcome similarly. The AI added relevant information in UPJS kidneys with impaired function, showing compensation of the contralateral kidney.

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Crystallisation of hydrous mafic magmas at high pressure is a subject of numerous petrologic and experimental studies since the last century and is mainly related to the process of continental crust formation and the possible link between mantle derived melts and low pressure granitoids. Albeit the sequence of crystallization is well constrained by experimental studies, the origin of exposed lower crustal rocks exposed on the earth surface is controversial. Ones line of argument is favouring high pressure crystallization of dry or wet mafic magmas, whereas others invoke partial melting of pre-existing crust. Therefore studies involving field, textural and chemical observations of exposed lower crust such as in Kohistan (Pakistan) or Talkeetna (Alaska) are crucial to understand the continental crust formation processes via arc magmatism. Epidote-bearing gabbros are very sparse and always associated with the deep part of continental crust (>30 km) as in the Kohistan Arc Complex (Pakistan) or in the Chelan Complex (western U.S.). Magmatic epidote is restricted to a small temperature interval above the water-saturated solidus of MORB and represent the last crystallizing liquids in lower crustal regions. However, epidote and melt stability at lower crustal pressures are not clearly established.¦The Chelan complex (western U.S.) at the base of the Cascadian Arc is composed mainly by peraluminous tonalité associated with gabbroic and ultramafic rocks and was traditionally interpreted as a migmatitic terrain. However field, chemical and mineralogical observations rather suggest a magmatic origin and point to a protracted crystallization at intermediate to high pressure ~ 1.0 GPa dominated by amphibole fractionation and followed by isobaric cooling down to 650°C. Crystal fractionation modelling using whole rock composition and field constraints is able to generate peraluminous tonalité. The modelled crystallisation sequence and the volume proportions are in agreement with experimental studies performed at these pressures. The Chelan complex was thus not formed during a partial melting event, but represent the sequence of crystallisation occurring at the base of the crust. Massive fractionation of hornblende is able to generate peraluminous tonalité without significant assimilation of crustal rock.¦Similarly to the Chelan complex, the base of the Kohistan arc is composed of cumulates derived by high pressure crystallization of hydrous magma. In garnet gabbros, epidote occurs as magmatic phase, crystallising from hydrous interstitial melt trapped between grain boundaries at lower crustal pressures (Ρ ~ 1.2 GPa) for temperature of (650-700 °C). Trace and REE signature in epidote indicate that epidote was formed through peritectic reaction involving garnet, clinopyroxene and plagioclase. At the beginning of the crystallisation epidote signature is dominated by REE content in the melt, whereas at the end the signature is dominated by reacting phases. Melt in equilibrium with epidote inferred from the partition coefficients available is similar to intrusive tonalité up the section indicating that hydrous melt was extracted from the garnet gabbros. In some gabbros epidote shows single homogeneous compositions, while in others coexisting epidote have different compositions indicating the presence of solvi along the Al-Fe3+ join. The overgowths are only observed in presence of paragonite in the assemblage, suggesting high water content. At high water content, the hydrous solidus is shift to lower temperature and probably intersects the solvi observed along the Al-Fe3+ join. Therefore, several compositions of epidote is stable at high water content.¦-¦La composition chimique de la croûte continentale est considérée comme similaire à celle du magmatisme calco-alcalin de marge continentale active (enrichissement en éléments mobiles dans les fluides, anomalies négatives en Nb, Ta et éléments à haut potentiel électronique, etc...). Cependant la nature andésitique de la croûte continentale (Si02 > 60 wt%), résultant des nombreuses intrusions de granitoïdes dans la croûte supérieure, est sujette à polémique et le lien entre les magmas dérivés du manteau et les roches évoluées de faible profondeur n'est pas clairement établi (fusion partielle de croûte basaltique, cristallisation fractionnée à haute pression, etc...).¦Les affleurements de croûte profonde sont rares mais précieux, car ils permettent d'observer les phénomènes se passant à grande profondeur. Le complexe de Chelan (Washington Cascades) en est un exemple. Formé à environ 30 km de profondeur, il est composé de roches gabbroïques et ultramafiques, ainsi que de tonalités, qui furent souvent interprétés comme le produit de la fusion partielle de la croûte. Cependant, les relations de terrain, la chimie des éléments majeurs et des éléments traces sont cohérentes avec l'évolution d'un complexe magmatique mafique dans la croûte profonde ou moyenne ( 1.0 GPa), dominée par le fractionnement de l'amphibole. Après son emplacement, le complexe a subi un refroidissement isobare jusqu'à des températures de l'ordre de 650 °C, déduit de la composition chimique des minéraux. Un bilan de masse contraint pax les observations de terrain permet de calculer la séquence et les volumes de fractionnement. Les faciès évolués légèrement hyperalumineux observés sur le terrain peuvent être générés par la cristallisation de 3 % de websterite à olivine, 12 % d'hornblendite à pyroxène 33 % d'hornblendite, 19 % de gabbros, 15 % de diorite et 2 % de tonalité. Nous montrons ainsi qu'une série de fractionnement contrôlée par l'amphibole permet de générer des tonalités sans assimilation de matériel crustal et l'exemple de Chelan illustre la viabilité de ce processus dans la formation de croûte continentale.¦Les réactions proches du solidus saturé en H20 dans les systèmes basaltiques à des pressions élevées restent énigmatiques. Diverses expériences tendent à montrer que l'épidote est stable dans ces conditions, mais rarement observée (décrite ?) comme phase primaire dans les systèmes naturels. Les épidotes trouvées dans les gabbros de Jijal (nord-Pakistan) montrent des textures de type .magmatique telles qu'observées dans les roches évoluées. Le contenu en terres rares de ces épidotes est très variable allant de signatures enrichies en terres rares légères impliquant la présence de liquide interstitiel à des signatures complètement déprimées en ces mêmes éléments, évoquant une cristallisation en coexistence avec du grenat. Ces diverses signatures reflètent un chemin de cristallisation en présence de liquide interstitiel et enregistrent des réactions péritectiques impliquant grenat, clinopyroxene et plagioclase à des pressions de ~ 1.2 GPa pour des températures de 650-700 °C. Cependant dans quelques échantillons deux ou trois compositions d'épidotes coexistent démontrant la présence de lacunes d'immiscibilité le long de la solution solide épidote-clinozoïsite. La forte teneur en H20 du liquide magmatique est certainement à l'origine de la coexistence de deux compositions distinctes.

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Purpose/Objective(s): Letrozole radiosensitizes breast cancer cells in vitro. In clinical settings, no data exist for the combination of letrozole and radiotherapy. We assessed concurrent and sequential radiotherapy and letrozole in the adjuvant setting.Materials/Methods: The present study is registered with ClinicalTrials.gov, number NCT00208273. This Phase 2 randomized trial was undertaken in two centers in France and one in Switzerland between January 12, 2005, and February 21, 2007. One hundred fifty postmenopausal women with early-stage breast cancer were randomly assigned after conserving surgery to either concurrent radiotherapy and letrozole (n = 75) or sequential radiotherapy and letrozole (n = 75). Randomization was open label with a minimization technique, stratified by investigational centers, chemotherapy (yes vs. no), radiation boost (yes vs. no), and value of radiation-induced lymphocyte apoptosis (#16% vs. .16%). The whole breast was irradiated to a total dose of 50 Gy in 25 fractions over 5 weeks. In the case of supraclavicular and internal mammary node irradiation, the dose was 44 - 50 Gy. Letrozole was administered orally once daily at a dose of 2 - 5 mg for 5 years (beginning 3 weeks pre-radiotherapy in the concomitant group, and 3 weeks postradiotherapy in the sequential group). The primary endpoint was the occurrence of acute (during and within 6 weeks of radiotherapy) and late (within 2 years) radiation-induced Grade 2 or worse toxic effects of the skin and lung (functional pulmonary test and lung CT-scan). Analyses were by intention-to-treat. The long-term follow-up after 2 years was only performed in Montpellier (n = 121) and evaluated skin toxicity (clinical examination every 6 months), lung fibrosis (one CT-scan yearly), cosmetic outcome.Results: All patients were analyzed apart from 1 in the concurrent group who withdrew consent before any treatment.Within the first 2 years (n = 149), no lung toxicity was identified by CT scan and no modification from baseline was noted by the lung diffusion capacity test. Two patients in each group had Grade 2 or worse late effects (both radiation-induced subcutaneous fibrosis [RISF]). After 2 years (n = 121), and with a median follow-up of 50 months (38-62), 2 patients (1 in each arm) presented a Grade 3 RISF. No lung toxicity was identified by CT scan. Cosmetic results (photographies) and quality of life was good to excellent. All patients who had Grade 3 subcutaneous fibrosis had an RILA value of 16% or less, irrespective of the sequence with letrozole.Conclusions:With long-term follow-up, letrozole can be safely delivered shortly after surgery and concomitantly with radiotherapy.