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1.
Opt Express ; 25(5): 4714-4719, 2017 Mar 06.
Article in English | MEDLINE | ID: mdl-28380742

ABSTRACT

We investigate the spatio-temporal dynamics of a ring cavity filled with a non-instantaneous Kerr medium and driven by a coherent injected beam. We show the existence of a stable mixed-mode solution that can be either extended or localized in space. The mixed-mode solutions are obtained in a regime where Turing instability (often called modulational instability) interacts with self-pulsing phenomenon (Andronov-Hopf bifurcation). We numerically describe the transition from stationary inhomogeneous solutions to a branch of mixed-mode solutions. We characterize this transition by constructing the bifurcation diagram associated with these solutions. Finally, we show stable localized mixed-mode solutions, which consist of time-periodic oscillations that are localized in space.

2.
Opt Lett ; 42(6): 1063-1066, 2017 Mar 15.
Article in English | MEDLINE | ID: mdl-28295092

ABSTRACT

Complex spatiotemporal dynamics have been a subject of recent experimental investigations in optical frequency comb microresonators and in driven fiber cavities with Kerr-type media. We show that this complex behavior has a spatiotemporal chaotic nature. We determine numerically the Lyapunov spectra, allowing us to characterize different dynamical behavior occurring in these simple devices. The Yorke-Kaplan dimension is used as an order parameter to characterize the bifurcation diagram. We identify a wide regime of parameters where the system exhibits a coexistence between the spatiotemporal chaos, the oscillatory localized structure, and the homogeneous steady state. The destabilization of an oscillatory localized state through radiation of counter-propagating fronts between the homogeneous and the spatiotemporal chaotic states is analyzed. To characterize better the spatiotemporal chaos, we estimate the front speed as a function of the pump intensity.

3.
Ann Oncol ; 26(6): 1123-1128, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25802238

ABSTRACT

BACKGROUND: Papillary renal cell carcinoma (PRCC), type 1 and type 2, represents 10%-15% of renal cell carcinomas (RCC). There is no standard first-line treatment of metastatic PRCC (mPRCC). Anti-angiogenics have shown activity in retrospective studies but no prospective studies in pure papillary histology have been reported, but one with foretinib. PATIENTS AND METHODS: A prospective phase II study evaluated sunitinib in first-line treatment of mPRCC. The primary end point was overall response rate (ORR). Secondary end points were progression-free survival (PFS) and overall survival (OS). RESULTS: Fifteen and 46 patients, respectively, with type 1 and type 2 mPRCC were enrolled. Using the MSKCC scoring system: 12 (20%), 33 (55%) and 9 (15%) patients were, respectively, in the favourable, intermediate or poor risk group and 7 undetermined. Median follow-up is 51.4 months. In type 1, 2 patients 13% [95% confidence interval (CI) 0.1-30.5] had a partial response (PR), 10 had stable disease (SD) with 5 (33%) ≥12 weeks. In type 2, 5 patients 11% (95% CI 1.9-20.3) had a PR, 25 had SD with 10(22%) ≥12 weeks. Median PFS was 6.6 months (95% CI 2.8-14.8) in type 1 and 5.5 months (95% CI 3.8-7.1) in type 2. Median OS was 17.8 (95% CI 5.7-26.1) and 12.4 (95% CI 8.2-14.3) months, respectively, in type 1 and 2. Safety was as expected with sunitinib for metastatic RCC. CONCLUSION: Sunitinib showed activity in treatment of type 1 and 2 mPRCC but lower than in clear-cell mRCC. Both PFS and OS are longer in type I PRCC. Sunitinib represents an acceptable option in first-line treatment of mPRCC.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Carcinoma, Renal Cell/drug therapy , Indoles/therapeutic use , Kidney Neoplasms/drug therapy , Pyrroles/therapeutic use , Aged , Angiogenesis Inhibitors/adverse effects , Carcinoma, Renal Cell/mortality , Carcinoma, Renal Cell/secondary , Disease Progression , Disease-Free Survival , Female , France , Humans , Indoles/adverse effects , Kaplan-Meier Estimate , Kidney Neoplasms/mortality , Kidney Neoplasms/pathology , Male , Middle Aged , Prospective Studies , Pyrroles/adverse effects , Risk Factors , Sunitinib , Time Factors , Treatment Outcome
4.
Ann Oncol ; 26(5): 865-872, 2015 May.
Article in English | MEDLINE | ID: mdl-25070543

ABSTRACT

BACKGROUND: The use of potential surrogate end points for overall survival, such as disease-free survival (DFS) or time-to-treatment failure (TTF) is increasingly common in randomized controlled trials (RCTs) in cancer. However, the definition of time-to-event (TTE) end points is rarely precise and lacks uniformity across trials. End point definition can impact trial results by affecting estimation of treatment effect and statistical power. The DATECAN initiative (Definition for the Assessment of Time-to-event End points in CANcer trials) aims to provide recommendations for definitions of TTE end points. We report guidelines for RCT in sarcomas and gastrointestinal stromal tumors (GIST). METHODS: We first carried out a literature review to identify TTE end points (primary or secondary) reported in publications of RCT. An international multidisciplinary panel of experts proposed recommendations for the definitions of these end points. Recommendations were developed through a validated consensus method formalizing the degree of agreement among experts. RESULTS: Recommended guidelines for the definition of TTE end points commonly used in RCT for sarcomas and GIST are provided for adjuvant and metastatic settings, including DFS, TTF, time to progression and others. CONCLUSION: Use of standardized definitions should facilitate comparison of trials' results, and improve the quality of trial design and reporting. These guidelines could be of particular interest to research scientists involved in the design, conduct, reporting or assessment of RCT such as investigators, statisticians, reviewers, editors or regulatory authorities.


Subject(s)
Endpoint Determination/standards , Gastrointestinal Stromal Tumors/therapy , Randomized Controlled Trials as Topic/standards , Research Design/standards , Sarcoma/therapy , Terminology as Topic , Consensus , Delphi Technique , Disease Progression , Disease-Free Survival , Endpoint Determination/classification , Gastrointestinal Stromal Tumors/diagnosis , Gastrointestinal Stromal Tumors/mortality , Humans , Randomized Controlled Trials as Topic/classification , Sarcoma/diagnosis , Sarcoma/mortality , Time Factors , Treatment Failure
5.
BMC Cancer ; 15: 700, 2015 Oct 15.
Article in English | MEDLINE | ID: mdl-26472661

ABSTRACT

BACKGROUND: Advanced malignant solitary fibrous tumors (SFTs) are rare soft-tissue sarcomas with a poor prognosis. Several treatment options have been reported, but with uncertain rates of efficacy. Our aim is to describe the activity of trabectedin in a retrospective, multi-center French series of patients with SFTs. METHODS: Patients were mainly identified through the French RetrospectYon database and were treated between January 2008 and May 2013. Trabectedin was administered at an initial dose of 1.5 mg/m(2), q3 weeks. The best tumor response was assessed according to the Response Evaluation Criteria In Solid Tumors 1.1. The Kaplan-Meier method was used to estimate median progression-free survival (PFS) and overall survival (OS). The growth-modulation index (GMI) was defined as the ratio between the time to progression with trabectedin (TTPn) and the TTP with the immediately prior line of treatment (TTPn-1). RESULTS: Eleven patients treated with trabectedin for advanced SFT were identified. Trabectedin had been used as second-line treatment in 8 patients (72.7 %) and as at least third-line therapy in a further 3 (27.3 %). The best RECIST response was a partial response (PR) in one patient (9.1 %) and stable disease (SD) in eight patients (72.7 %). Disease-control rate (DCR = PR + SD) was 81.8 %. After a median follow-up of 29.2 months, the median PFS was 11.6 months (95 % CI = 2.0; 15.2 months) and the median OS was 22.3 months (95 % CI = 9.1 months; not reached). The median GMI was 1.49 (range: 0.11-4.12). CONCLUSION: Trabectedin is a very promising treatment for advanced SFTs. Further investigations are needed.


Subject(s)
Dioxoles/administration & dosage , Prognosis , Sarcoma/drug therapy , Solitary Fibrous Tumors/drug therapy , Tetrahydroisoquinolines/administration & dosage , Adult , Disease-Free Survival , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Neoplasm Staging , Retrospective Studies , Sarcoma/pathology , Solitary Fibrous Tumors/pathology , Trabectedin , Treatment Outcome
6.
Prog Urol ; 25(7): 370-8, 2015 Jun.
Article in French | MEDLINE | ID: mdl-25937373

ABSTRACT

OBJECTIVE: Radical prostatectomy (RP) is an oncologic and functional challenge. Few series compare prospectively the two approaches, open retropubic (ORP) and laparoscopic robot-assisted RP (LRARP). The objective was to compare the oncological and functional results of ORP and LRARP. MATERIAL AND METHODS: From January 2009 to March 2012, two practiced surgeons conducted 304 consecutive RP: respectively 129 ORP and 175 LRARP. Preoperative, perioperative and postoperative data (location and size of positive surgical margins [PSM]) were recorded prospectively and compared with oncological results (PSM, biochemical recurrence-free survival [BCR]) and functional outcomes (urinary and erectile) by self-validated questionnaires (USP, IIEF-15). The comparison was made by the Chi(2) test and Student t-test for qualitative and quantitative variables. RESULTS: The preoperative data 2 groups were comparable. MCP rate was 13.2% for the ORP and 20% for the LRARP (ns) and was 1.4% and 29.6% (ORP) versus 9.4% and 36.7% (LRARP) for pT2 and pT3 for respectively (P=0.078). BCR was the same in both groups (95.2% at 13.1 months). At 12 months, the results of continence showed no difference (P=0.49) and about erectile function, the EF-score was significantly higher in LRARP: 22 versus 17 for the ORP (P=0.03). CONCLUSION: Oncological results were comparable after ORP and LRARP. The recovery of continence was excellent regardless of the surgical technique, the recovery of erectile function a bit faster by LRARP. LEVEL OF EVIDENCE: 3.


Subject(s)
Laparoscopy , Prostatectomy/methods , Prostatic Neoplasms/surgery , Robotic Surgical Procedures , Adult , Aged , Humans , Male , Middle Aged , Penile Erection , Prospective Studies , Treatment Outcome , Urination
7.
Ann Oncol ; 25(12): 2425-2432, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25294887

ABSTRACT

BACKGROUND: The EORTC-STBSG coordinated two large trials of adjuvant chemotherapy (CT) in localized high-grade soft tissue sarcoma (STS). Both studies failed to demonstrate any benefit on overall survival (OS). The aim of the analysis of these two trials was to identify subgroups of patients who may benefit from adjuvant CT. PATIENTS AND METHODS: Individual patient data from two EORTC trials comparing doxorubicin-based CT to observation only in completely resected STS (large resection, R0/marginal resection, R1) were pooled. Prognostic factors were assessed by univariate and multivariate analyses. Patient outcomes were subsequently compared between the two groups of patients according to each analyzed factor. RESULTS: A total of 819 patients had been enrolled with a median follow-up of 8.2 years. Tumor size, high histological grade and R1 resection emerged as independent adverse prognostic factors for relapse-free survival (RFS) and OS. Adjuvant CT is an independent favorable prognostic factor for RFS but not for OS. A significant interaction between benefit of adjuvant CT and age, gender and R1 resection was observed for RFS and OS. Males and patients >40 years had a significantly better RFS in the treatment arms, while adjuvant CT was associated with a marginally worse OS in females and patients <40 years. Patients with R1 resection had a significantly better RFS and OS favoring adjuvant CT arms. CONCLUSION: Adjuvant CT is not associated with a better OS in young patients or in any pathology subgroup. Poor quality of initial surgery is the most important prognostic and predictive factor for utility of adjuvant CT in STS. Based on these data, we conclude that adjuvant CT for STS remains an investigational procedure and is not a routine standard of care.


Subject(s)
Antibiotics, Antineoplastic/therapeutic use , Doxorubicin/therapeutic use , Sarcoma/drug therapy , Chemotherapy, Adjuvant , Disease-Free Survival , Female , Humans , Male , Prognosis
8.
Nanotechnology ; 25(2): 025701, 2014 Jan 17.
Article in English | MEDLINE | ID: mdl-24334512

ABSTRACT

We have carried out nanoindentation studies of gold in which the indenter is atomically characterized by field-ion microscopy and the scale of deformation is sufficiently small to be directly compared with atomistic simulations. We find that many features of the experiment are correctly reproduced by molecular dynamics simulations, in some cases only when an atomically rough indenter rather than a smooth repulsive-potential indenter is used. Heterogeneous nucleation of dislocations is found to take place at surface defect sites. Using input from atomistic simulations, a model of indentation based on stochastic transitions between continuum elastic-plastic states is developed, which accurately predicts the size distributions of plastic 'pop-in' events and their dependence on tip geometry.

9.
Ann Oncol ; 24(10): 2672-2676, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23868907

ABSTRACT

BACKGROUND: To determine the activity of radiotherapy in patients with inoperable desmoid-type fibromatosis (DF) a multicenter prospective phase II trial was carried out. MATERIALS AND METHODS: Patients with inoperable progressive disease of primary, recurrent or incompletely resected lesions received a dose of 56 Gy in 28 fractions. Follow-up MRI studies were carried out every 3 months for 2 years and thereafter every 6 months. The primary end point was local control rate at 3 years, estimated by a nonparametric method for interval-censored survival data. Secondary end points were objective tumor response, acute and late toxic effect. RESULTS: Forty-four patients (27 F/17 M) were enrolled from 2001 to 2008. Median age was 39.5 years. Main tumor sites included trunk 15 (34.1%) and extremities 27 (61.3%). Median follow-up was 4.8 years. The 3-year local control rate was 81.5% (90% one-sided confidence interval 74% to 100%). Best overall response during the first 3 years was complete response (CR) 6 (13.6%), partial response (PR) 16 (36.4%), stable disease 18 (40.9%), progressive disease 3 (6.8%) and nonassessable 1 (2.3%). Five patients developed new lesions. After 3 years, the response further improved in three patients: (CR 2, PR 1). Acute grade 3 side-effects were limited to skin, mucosal membranes and pain. Late toxic effect consisted of mild edema in 10 patients. CONCLUSIONS: Moderate dose radiotherapy is an effective treatment of patients with DF. Response after radiation therapy is slow with continuing regression seen even after 3 years.


Subject(s)
Fibromatosis, Aggressive/radiotherapy , Neoplasm Recurrence, Local/radiotherapy , Adolescent , Adult , Aged , Female , Fibromatosis, Aggressive/diagnostic imaging , Follow-Up Studies , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Pilot Projects , Prospective Studies , Radiography , Survival Analysis , Treatment Outcome , Young Adult
10.
Encephale ; 38(6): 519-23, 2012 Dec.
Article in French | MEDLINE | ID: mdl-23200619

ABSTRACT

INTRODUCTION: The frequency of neuropsychiatric symptoms in systemic lupus varies between 14 and 75%. Their mechanisms are multiple and their non-specificity makes the etiological diagnosis more difficult. The MRI lesions are dominated by small white matter hyperintensities. CASE REPORT: We report a case of 17-year-old girl without medical, surgical or familial past, who presented an acute psychotic episode with fever. The neurological examination showed a pyramidal syndrome. The brain MRI objectified diffuse, bilateral and symmetrical white and gray matter hyperintensities. The diagnosis of neuropsychiatric lupus was retained with association of more than four criteria among the 11 ARA revised criteria: pleural effusion, neuropsychiatric manifestations, anemia, lymphopenia and positive ANA. The treatment was based on corticosteroids. The evolution was fatal. DISCUSSION: Psychiatric disorders are polymorphic and appear during the course of the disease or at diagnosis; they can be seen in 20% of cases and are a sign of a poor prognosis. Most often these disorders are a non-specific reaction, but severe clinical forms can be observed as suicidal risk or mood disorders (depression, mania...), or acute psychotic episode. CONCLUSION: The diagnosis of neuropsychiatric lupus must be evoked systematically in atypical neuropsychiatric disorders especially when confronted with minimal biological and brain imaging abnormalities.


Subject(s)
Brain/pathology , Diffusion Magnetic Resonance Imaging , Lupus Vasculitis, Central Nervous System/diagnosis , Magnetic Resonance Imaging , Psychotic Disorders/diagnosis , Acute Disease , Adrenal Cortex Hormones/therapeutic use , Adult , Diagnosis, Differential , Fatal Outcome , Female , Humans , Lupus Vasculitis, Central Nervous System/drug therapy , Neurologic Examination , Psychotic Disorders/drug therapy
11.
Br J Cancer ; 104(10): 1544-50, 2011 May 10.
Article in English | MEDLINE | ID: mdl-21505457

ABSTRACT

BACKGROUND: We investigated prognostic factors (PFs) for 90-day mortality in a large cohort of advanced/metastatic soft tissue sarcoma (STS) patients treated with first-line chemotherapy. METHODS: The PFs were identified by both logistic regression analysis and probability tree analysis in patients captured in the Soft Tissue and Bone Sarcoma Group (STBSG) database (3002 patients). Scores derived from the logistic regression analysis and algorithms derived from probability tree analysis were subsequently validated in an independent study cohort from the French Sarcoma Group (FSG) database (404 patients). RESULTS: The 90-day mortality rate was 8.6 and 4.5% in both cohorts. The logistic regression analysis retained performance status (PS; odds ratio (OR)=3.83 if PS=1, OR=12.00 if PS ≥2), presence of liver metastasis (OR=2.37) and rare site metastasis (OR=2.00) as PFs for early death. The CHAID analysis retained PS as a major discriminator followed by histological grade (only for patients with PS ≥2). In both models, PS was the most powerful PF for 90-day mortality. CONCLUSION: Performance status has to be taken into account in the design of further clinical trials and is one of the most important parameters to guide patient management. For those patients with poor PS, expected benefits from therapy should be weighed up carefully against the anticipated toxicities.


Subject(s)
Sarcoma/drug therapy , Sarcoma/mortality , Soft Tissue Neoplasms/drug therapy , Soft Tissue Neoplasms/mortality , Adult , Cohort Studies , Europe/epidemiology , Female , Humans , Logistic Models , Male , Middle Aged , Risk Factors , Sarcoma/pathology , Soft Tissue Neoplasms/pathology , Treatment Outcome
12.
Ann Oncol ; 22(6): 1266-1272, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21183581

ABSTRACT

BACKGROUND: The prognosis of advanced soft tissue sarcoma remains poor. Many phase II trials investigating new regimens have been published in the last 10 years. MATERIALS AND METHODS: Full English-language reports of phase II clinical trials from January 1999 to October 2009 have been reviewed. We have defined those that provided 3- and 6-month progression-free survival rates (PFSR) >39% and 14%, respectively, as promising second-line regimens. For studies enrolling both chemonaive and pretreated patients, we have compared the reported PFSR3 to the expected PFSR3 of an active treatment administered in the same proportions of pretreated and nonpretreated patients. RESULTS: Forty-nine trials were identified. Among the trials investigating new regimens in pretreated patients alone, the promising second-line regimens were ifosfamide, brostallicin, pazopanib (except in liposarcoma), temozolomide, trabectedin, dacarbazine-gemcitabine and docetaxel (Taxotere)-gemcitabine combinations (in uterine leiomyosarcoma). Among the trials enrolling both chemonaive and pretreated patients, most regimens reached the level of efficacy; moreover, in three trials, the reported PFSR3 was particularly high: weekly paclitaxel (Taxol) in angiosarcoma, docetaxel-gemcitabine combination (in uterine leiomyosarcoma) and oral perifosine. CONCLUSIONS: In the past 10 years, several drugs or combinations have demonstrated promising activity in exploratory phase II trials and warrant further investigation in appropriate phase III trials.


Subject(s)
Antineoplastic Agents/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Sarcoma/drug therapy , Clinical Trials as Topic , Humans , Prognosis , Sarcoma/diagnosis , Soft Tissue Neoplasms/diagnosis , Soft Tissue Neoplasms/drug therapy
13.
Ann Oncol ; 22(1): 207-214, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20656792

ABSTRACT

BACKGROUND: the role of chemotherapy in advanced malignant peripheral nerve sheath tumor (MPNST) is unclear. PATIENTS AND METHODS: chemotherapy-naive soft tissue sarcomas (STS) patients treated on 12 pooled nonrandomized and randomized European Organization for Research and Treatment of Cancer Soft Tissue and Bone Sarcoma Group trials were retrospectively analyzed. Clinical outcomes, overall survival, progression-free survival (PFS) and response were determined for MPNST and other STS histotypes and compared. Additionally, prognostic factors within the MPNST population were defined. Studied cofactors were demographics, sarcoma history, disease extent and chemotherapy regimen. RESULTS: after a median follow-up of 4.1 years, 175 MPNST out of 2675 eligible STS patients were analyzed. Outcome was similar for MPNST versus other STS histotypes, with a response rate, median PFS and overall survival of 21% versus 22%, 17 versus 16 weeks and 48 versus 51 weeks, respectively. Performance status was an independent prognostic factor for overall survival. Chemotherapy regimen was an independent prognostic factor for response (P < 0.0001) and PFS (P = 0.009). Compared with standard first-line doxorubicin, the doxorubicin-ifosfamide regimen had the best response, whereas ifosfamide had the worst prognosis. CONCLUSION: this series indicates the role of chemotherapy in treatment of advanced MPNST. This first comparison showed similar outcomes for MPNST and other STS histotypes. The apparent superiority of the doxorubicin-ifosfamide regimen justifies further investigations of this combination in randomized trials.


Subject(s)
Nerve Sheath Neoplasms/drug therapy , Sarcoma/drug therapy , Adolescent , Adult , Aged , Child , Disease-Free Survival , Female , Humans , Male , Middle Aged , Young Adult
14.
J Hazard Mater ; 163(1): 463-7, 2009 Apr 15.
Article in English | MEDLINE | ID: mdl-18687523

ABSTRACT

In this paper, experimental methods and results are reported on the removal of the dye Green Bezanyl-F2B (an acid dye) from MgAlCO(3) (HT) and from intercalated anionic surfactant, "sodium dodecylsulfate (SDS)", into the Mg-Al layered double hydroxides by the calcination-rehydration reaction using Mg-Al oxide precursors calcined at 773 K. Dodecylsulfate hydrotalcite was prepared by the calcination-rehydration method. The surfactant intercalation in the interlayer space of hydrotalcite was investigated by XRD and FT-IR spectroscopy where the resulting materials were found to be similar to those reported in the literature and were used to remove an acid dye from an aqueous solution. Equilibrium time and rate-determining step of the dye Green Bezanyl-F2B sorption were determined. Two simplified kinetic models were tested to investigate the sorption. The adsorption capacity data were also fitted to Langmuir and Freundlich equation as well. The sorption data fitted to the Langmuir model gave good values of the determination coefficient.


Subject(s)
Acids/chemistry , Coloring Agents/chemistry , Hydroxides/chemistry , Magnesium/chemistry , Adsorption , Aluminum/chemistry , Hydrogen-Ion Concentration , Solutions , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
15.
Colloids Surf B Biointerfaces ; 66(2): 240-5, 2008 Oct 15.
Article in English | MEDLINE | ID: mdl-18693090

ABSTRACT

A biological sludge--waste-activated sludge (WAS)--from a dairy filtering station was investigated for the removal of trivalent chromium from aqueous solution. Kinetic results revealed that chromium adsorption was instantaneous. The removal rate increases up to pH 4 for contact times beyond 20 min. The equilibrium state is attained in 30 min in all the considered systems. The reaction orders as well as the diffusion rate constant were determined. Values adsorption isotherms measured at pH 3 generally followed the Langmuir model. The maximum uptake capacity was 25.64 mg/g. Values of thermodynamic parameters show that chromium (III) sorption on WAS is an exothermic process. This study provides an opportunity for the removal of heavy metals such as chromium from aqueous solutions using a low-cost biosolid as adsorbent support.


Subject(s)
Chromium/isolation & purification , Sewage/chemistry , Water Pollutants, Chemical/isolation & purification , Adsorption , Chromium/chemistry , Diffusion , Hydrogen-Ion Concentration , Surface Properties , Temperature , Thermodynamics , Time Factors , Water Pollutants, Chemical/chemistry
16.
J Colloid Interface Sci ; 293(2): 270-7, 2006 Jan 15.
Article in English | MEDLINE | ID: mdl-16023127

ABSTRACT

An Algerian bentonite was purified and modified by intercalation of 8-hydroxyquinolinium ion. These materials were characterized by X-ray diffraction, infrared spectroscopy, and thermal analysis. Comparative batch experiments were performed using bentonite-oxine complex (B-oxine) and sodic bentonite (B-Na) for removing cadmium from aqueous solutions. Kinetics study results of cadmium removal with B-Na and B-oxine fit a pseudo-second-order model. The adsorption isotherm data follow the Langmuir equation in which parameters were calculated. B-oxine has a better cadmium removal capacity (61.35 mg/g) than B-Na (29.41 mg/g). Calculated thermodynamic parameters using the van't Hoff equation showed that the removal process is endothermic with B-oxine and exothermic with B-Na. A mechanism of ion exchange followed by complexation-precipitation is suggested for cadmium removal with B-oxine.

17.
Cancer Radiother ; 20(1): 18-23, 2016 Feb.
Article in French | MEDLINE | ID: mdl-26749214

ABSTRACT

PURPOSE: Optimal timing of neck dissection remains debated in the conservative management of patients with locoregionally advanced squamous cell carcinoma of the head and neck. PATIENTS AND METHODS: The files of 63 patients with radiographic evidence of bulky or necrotic nodal metastases treated by up-front neck dissection and definitive radiotherapy between 2000 and 2012 at two institutions were retrospectively reviewed. RESULTS: The primary site was oropharyngeal, hypopharyngeal or laryngeal in 63%, 21% and 13% cases, respectively. Overall, 83% of the tumours were staged pN2b or more. Extracapsular spread was found in 48 cases (77%). After a 48-month median follow-up, the 3-year locoregional control and overall survival were 88% and 68%, respectively. Only one isolated failure occurred in the dissected neck. CONCLUSION: This combination therapy provides a good locoregional tumour control. It should be considered as an option in laryngeal, hypopharyngeal or oropharyngeal squamous cell carcinomas with bulky or necrotic nodal metastases at presentation.


Subject(s)
Carcinoma, Squamous Cell/therapy , Head and Neck Neoplasms/therapy , Neck Dissection , Neoadjuvant Therapy , Adult , Aged , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/pathology , Chemotherapy, Adjuvant , Dose Fractionation, Radiation , Female , Follow-Up Studies , Head and Neck Neoplasms/mortality , Head and Neck Neoplasms/pathology , Humans , Lymphatic Metastasis , Male , Middle Aged , Radiotherapy, Adjuvant , Retrospective Studies
18.
Clin Oncol (R Coll Radiol) ; 27(1): 48-55, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25300878

ABSTRACT

AIMS: Recent data suggest that patients with pulmonary metastases from sarcomas might benefit from ablation of their metastases. Some data are available regarding osteosarcomas/angiosarcomas and lung metastases. The purpose of this study was to assess the efficacy of local ablative treatment on the survival of patients with oligometastases (one to five lesions, any metastatic site, any grade/histology) from sarcomas. MATERIALS AND METHODS: A multicentric retrospective study of the French Sarcoma Group was conducted in sarcoma patients with oligometastases who were treated between 2000 and 2012. Survival was analysed using multivariate sensitivity analyses with propensity scores to limit bias. RESULTS: Of the 281 patients evaluated, 164 patients received local treatment for oligometastases between 2000 and 2012. The groups' characteristics were similar in terms of tumour size and remission of the primary tumours. The median follow-up was 25.7 months; 129 (45.9%) patients had died at this point. The median overall survivals were 45.3 (95% confidence interval = 34-73) months for the local treatment group and 12.6 for the other group (95% confidence interval = 9.33-22.9). Survival was better among patients who received local treatment (hazard ratio = 0.47; 95% confidence interval = 0.29-0.78; P < 0.001). Subgroup analyses revealed similar findings in the patients with single oligometastases (hazard ratio = 0.48; 95% confidence interval = 0.28-0.82; P = 0.007); a significant benefit was observed for grade 3, and a trend was observed for grade 2. CONCLUSION: Local ablative treatment seemed to improve the overall survival of the patients who presented with oligometastatic sarcomas, including soft tissue and bone sarcomas. The survival benefit remained after repeated local treatments for several oligometastatic events. Surgery yielded the most relevant results, but alternative approaches (i.e. radiofrequency ablation and radiotherapy) seemed to be promising. The relevance of these results is strengthened by our analysis, which avoided biases by restricting the population to patients with oligometastatic disease and used propensity scores.


Subject(s)
Lung Neoplasms/secondary , Lung Neoplasms/surgery , Sarcoma/secondary , Sarcoma/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Multivariate Analysis , Neoplasm Metastasis , Prognosis , Retrospective Studies , Young Adult
19.
Protein Sci ; 9(6): 1162-76, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10892809

ABSTRACT

We describe a new classifier for protein secondary structure prediction that is formed by cascading together different types of classifiers using neural networks and linear discrimination. The new classifier achieves an accuracy of 76.7% (assessed by a rigorous full Jack-knife procedure) on a new nonredundant dataset of 496 nonhomologous sequences (obtained from G.J. Barton and J.A. Cuff). This database was especially designed to train and test protein secondary structure prediction methods, and it uses a more stringent definition of homologous sequence than in previous studies. We show that it is possible to design classifiers that can highly discriminate the three classes (H, E, C) with an accuracy of up to 78% for beta-strands, using only a local window and resampling techniques. This indicates that the importance of long-range interactions for the prediction of beta-strands has been probably previously overestimated.


Subject(s)
Protein Structure, Secondary , Proteins/chemistry , Neural Networks, Computer
20.
Biochimie ; 77(11): 835-9, 1995.
Article in English | MEDLINE | ID: mdl-8824761

ABSTRACT

We describe how we can reduce the periodic bending motions in the simulation in vacuo of the molecular dynamics of a short DNA fragment containing the Gly 12 hot spot of the K-ras oncogene and having at its center a mismatch CA+.


Subject(s)
Genes, ras , Models, Molecular , Base Sequence , DNA/genetics , Hydrogen Bonding , Molecular Sequence Data
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