Effect of Fe substitution on the structural, magnetic and electron-transport properties of half-metallic Co2TiSi

The structural, magnetic and electron-transport properties of Co2Ti1-xFexSi (x = 0, 0.25, 0.5) ribbons prepared by arc-melting and melt-spinning were investigated. The rapidly quenched Co2Ti0.5Fe0.5Si crystallized in the cubic L21 structure whereas Co2Ti0.75Fe0.25Si and Co2TiFe0Si showed various degrees of B2-type disorder. At room temperature, all the samples are ferromagnetic, and the Curie temperature increased from 360 K for Co2TiSi to about 800 K for Co2Ti0.5Fe0.5Si. The measured magnetization also increased due to partial substitution of Fe for Ti atoms. The ribbons are moderately conducting and show positive temperature coefficient of resistivity with the room temperature resistivity being between 360 µΩcm and 440 µΩcm. The experimentally observed structural and magnetic properties are consistent with the results of first-principle calculations. Our calculations also indicate that the Co2Ti1-xFexSi compound remains nearly half-metallic for x ≤ 0.5. The predicted large band gaps and high Curie temperatures much above room temperature make these materials promising for room temperature spintronic and magnetic applications

Effect of Fe substitution on the structural, magnetic and electron-transport properties of half-metallic Co2TiSi

The structural, magnetic and electron-transport properties of Co2Ti1-xFexSi (x = 0, 0.25, 0.5) ribbons prepared by arc-melting and melt-spinning were investi- gated. The rapidly quenched Co2Ti0.5Fe0.5Si crystallized in the cubic L21 structure whereas Co2Ti0.75Fe0.25Si and Co2TiFe0Si showed various degrees of B2-type disorder. At room temperature, all the samples are ferromagnetic, and the Curie tem- perature increased from 360 K for Co2TiSi to about 800 K for Co2Ti0.5Fe0.5Si. The measured magnetization also increased due to partial substitution of Fe for Ti atoms. The ribbons are moderately conducting and show positive tempera- ture coefficient of resistivity with the room temperature resistivity being between 360 μΩcm and 440 μΩcm. The experimentally observed structural and magnetic prop- erties are consistent with the results of first-principle calculations. Our calculations also indicate that the Co2Ti1-xFexSi compound remains nearly half-metallic for x ≤ 0.5. The predicted large band gaps and high Curie temperatures much above room temperature make these materials promising for room temperature spintronic and magnetic applications

Volumetry - an alternative to assess therapy response for malignant pleural mesothelioma?

The purpose of this study was to assess robustness of volumetric measurement of malignant pleural mesothelioma (MPM) before and after chemotherapy to modified RECIST. Thirty patients with digitally available chest CT scan before and after 3 cycles of chemotherapy were included. Three readers assessed independently tumour response using two different methods: Modified RECIST criteria and tumour volumetric approach using dedicated software (Myrian, Intrasense, France). Inter-rater reliability of uni-dimensional and volumetric measurements was assessed using intraclass correlation. tumour response classification for modified RECIST was compared to volumetric approach applying uni-dimensional RECIST volumetric equivalent criteria. The determination of uni-dimensional tumour measurement (RECIST) revealed a low inter-rater reliability (0.55) and a low interobserver agreement for tumour response classification (general kappa 0.33). Only 14 patients were classified equally. A high inter-rater reliability (0.99) and interobserver agreement (general kappa 0.9)) was found for absolute tumour volumes (volumetric measurements). 27 cases were classified equally. The number of cases classified as "stable disease" was higher for volumetric approach using tumour equivalent criteria compared to modified RECIST. Volumetric measurement of MPM on CT-scan using Myrian software is a reliable, reproducible and sensitive method to measure tumour volume and hence therapy response after induction chemotherapy

Repeated lung volume reduction surgery is successful in selected patients

OBJECTIVES Lung volume reduction surgery (LVRS) improves dyspnoea, quality of life and may even prolong survival in carefully selected patients with end-stage emphysema. The benefit may be sustained for several years and vanishes with the natural progression of the disease. Data on repeated surgical treatment of emphysema are scarce. The aim of this study was to evaluate the safety, effects and outcomes of repeated LVRS (Re-LVRS) in patients no longer benefiting from their initial LVRS. METHODS Between June 2002 and December 2013, 22 patients (9 females) with advanced emphysema underwent Re-LVRS at a median of 60 months (25–196) after their initial LVRS. While initial LVRS was performed thoracoscopically as a bilateral procedure, Re-LVRS was performed unilaterally by a video-assisted thoracoscopic technique in 19 patients and, due to adhesions, by thoracotomy in 3 patients. Pulmonary function test (PFT) was performed at 3 and 12 months postoperatively. RESULTS Lung function at Re-LVRS was similar to that prior to the first LVRS. The 90-day mortality rate was 0%. The first patient died 15 months postoperatively. The median hospitalization time after Re-LVRS was significantly longer compared with the initial LVRS [14 days, interquartile range (IQR): 11–19, vs 9 days, IQR: 8–14; P = 0.017]. The most frequent complication was prolonged air leak with a median drainage time of 11 days (IQR: 6–13); reoperations due to persistent air leak were necessary in 7 patients (32%). Five patients (23%) had no complications. Lung function and Medical Research Council (MRC) score improved significantly for up to 12 months after Re-LVRS, with results similar to those after initial bilateral LVRS. The average increase in the forced expiratory volume in 1 s (FEV1) was 25% (a 7% increase over the predicted value or 0.18 l) at 3 months, and the mean reduction in hyperinflation, assessed by relative decrease in RV/TLC (residual volume/total lung capacity), was 12% at 3 months (a decrease of 8% in absolute ratios). The mean MRC breathlessness score decreased significantly after 3 months (from 3.7 to 2.2). CONCLUSIONS Re-LVRS can be performed successfully in carefully selected patients as a palliative treatment. It may be performed as a bridge to transplantation or in patients with newly diagnosed intrapulmonary nodules or during elective cardiac surgery. Morbidity is acceptable and outcomes may be satisfactory with significantly improved lung function and reduced dyspnoea for at least 12 months postoperatively

Induction of senescence markers after neo-adjuvant chemotherapy of malignant pleural mesothelioma and association with clinical outcome: an exploratory analysis

The aim of this study was to assess the induction of senescence markers versus apoptosis pathways in malignant pleural mesothelioma (MPM) tumour samples before and after neo-adjuvant platinum-based chemotherapy and to investigate their relationship with clinical outcome. Specific senescence pathways were assessed by quantifying the expression of p21 and plasminogen activator inhibitor-1 (PAI-1) for the p21-p53 pathway, IGFBP7 for the IGF pathway and ALDH1A3 for the IFN pathway. p21 and PAI-1 expression were also assessed by immunohistochemistry. In addition, beta-galactosidase activity staining at pH 6.0 was performed. Apoptosis was determined by TUNEL assay. Clinical outcome was assessed by modified RECIST criteria, progression-free and overall survival. In a training set (n=9 patients) paired comparison demonstrated a significant increase in p21 (p<0.05), PAI-1 (p<0.01) and apoptosis (p<0.01) after neo-adjuvant chemotherapy. The patients with the highest increase in PAI-1 had stable disease, whilst patients with little change in senescence markers accompanied by a high increase in apoptosis had an objective response after chemotherapy. The hypothesis that stable disease might be associated with an increase in senescence markers was confirmed in a tissue microarray (n=26 patients) using p21 and PAI-1 immunohistochemistry as readouts. For patients where survival and time to progression data were available, increased PAI-1 levels were significantly associated with a worst outcome. Our results demonstrate induction of senescence markers by neo-adjuvant chemotherapy in a proportion of patients with MPM and its potential association with a poor outcome

Effect of Fe substitution on the structural, magnetic and electron-transport properties of half-metallic Co 2

The structural, magnetic and electron-transport properties of Co2Ti1−xFexSi (x = 0, 0.25, 0.5) ribbons prepared by arc-melting and melt-spinning were investigated. The rapidly quenched Co2Ti0.5Fe0.5Si crystallized in the cubic L21 structure whereas Co2Ti0.75Fe0.25Si and Co2TiFe0Si showed various degrees of B2-type disorder. At room temperature, all the samples are ferromagnetic, and the Curie temperature increased from 360 K for Co2TiSi to about 800 K for Co2Ti0.5Fe0.5Si. The measured magnetization also increased due to partial substitution of Fe for Ti atoms. The ribbons are moderately conducting and show positive temperature coefficient of resistivity with the room temperature resistivity being between 360 μΩcm and 440 μΩcm. The experimentally observed structural and magnetic properties are consistent with the results of first-principle calculations. Our calculations also indicate that the Co2Ti1−xFexSi compound remains nearly half-metallic for x ≤ 0.5. The predicted large band gaps and high Curie temperatures much above room temperature make these materials promising for room temperature spintronic and magnetic applications

Induction of senescence markers after neo-adjuvant chemotherapy of malignant pleural mesothelioma and association with clinical outcome: An exploratory analysis

The aim of this study was to assess the induction of senescence markers versus apoptosis pathways in malignant pleural mesothelioma (MPM) tumour samples before and after neo-adjuvant platinum-based chemotherapy and to investigate their relationship with clinical outcome. Specific senescence pathways were assessed by quantifying the expression of p21 and plasminogen activator inhibitor-1 (PAI-1) for the p21-p53 pathway, IGFBP7 for the IGF pathway and ALDH1A3 for the IFN pathway. p21 and PAI-1 expression were also assessed by immunohistochemistry. In addition, beta-galactosidase activity staining at pH 6.0 was performed. Apoptosis was determined by TUNEL assay. Clinical outcome was assessed by modified RECIST criteria, progression-free and overall survival. In a training set (n = 9 patients) paired comparison demonstrated a significant increase in p21 (p < 0.05), PAI-1 (p < 0.01) and apoptosis (p < 0.01) after neo-adjuvant chemotherapy. The patients with the highest increase in PAI-1 had stable disease, whilst patients with little change in senescence markers accompanied by a high increase in apoptosis had an objective response after chemotherapy. The hypothesis that stable disease might be associated with an increase in senescence markers was confirmed in a tissue microarray (n = 26 patients) using p21 and PAI-1 immunohistochemistry as readouts. For patients where survival and time to progression data were available, increased PAI-1 levels were significantly associated with a worst outcome. Our results demonstrate induction of senescence markers by neo-adjuvant chemotherapy in a proportion of patients with MPM and its potential association with a poor outcome. © 2010 Elsevier Ltd. All rights reserved