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Abstract: Introduction: Curative therapy for patients with small-cell lung cancer (SCLC) is based on multidrug chemotherapy combinations and radiotherapy. After a long time follow-up, the aim of the study was to evaluate the efficacy and toxicity of sequential chemo-radiotherapy and the effect of prophylactic cranial irradiation (PCI). Methods: From 1995–2005, 96 patients with SCLC (64 limited-disease [LD], 32 extensive-disease [ED]; median age 61years [range 39–79]) were treated at our department with varying chemotherapy regimens and sequential mediastinal radiotherapy (50Gy+10Gy boost in case of residual disease after chemotherapy). Afterwards, 15 patients with LD, good general condition and at least partial response after local treatment received PCI (30Gy). Results: After a median follow-up of 78.6months, 20 patients remained alive (20.8%, median survival time 18.2months). The 2-/5-year overall survival rates were 33.8% and 12.6%, the 2-/5-year loco-regional control rates were 30.3% and 24.5%, respectively. Distant metastases occurred in 43 patients (24 cerebral). Cerebral metastasis occurred in 6.7% and 27.2% of the patients with PCI and without PCI respectively. Only tumor stage showed a statistically significant impact on overall survival and loco-regional control in multivariate analysis. Radiotherapy was well tolerated. Grade 3/4 toxicity occurred in seven patients. Prognosis of patients with SCLC remains poor. Administration of PCI in selected patients bears a decrease in the incidence of cerebral metastases. Alternative chemotherapy schemes as well as irradiation schemes and techniques should be the substance of future randomized trials. [Copyright &y& Elsevier]

Abstract: Metabolic and functional studies of the amyloid precursor protein (APP) in platelets have advanced our understanding of Alzheimer''s disease (AD). Here we report that human platelets contain Aβ peptides, process and secrete them constitutively. Platelets generate formerly unkown Aβ-species by differential processing of APP. Release of Aβ peptides were also increased by platelet activation with thrombin, indicating the existence of a regulated exocytotic pathway. We showed that Aβ-levels, Aβ-processing patterns and Aβ-release kinetics were regulated by thrombin. In controls, release of Aβ peptide species (Aβ 1-40/42 and 1-37/38/39/) continued for more than 4h, while thrombin activated cells ceased secretion after 1h at large. Treatment of platelets with prostaglandine 2 slowed this process down. Intracellular Aβ peptide concentrations decreased steadily until no peptides could be detected after 20h (control) or after 4h (thrombin) in cultured platelets. [Copyright &y& Elsevier]

Abstract: SBA-12 mesoporous silica was modified by 3-aminopropyl (AP), 3-(methylamino)propyl (MAP) and 3-(phenylamino)propyl (PAP) ligands. The electronic effects in AP, MAP and PAP ligands resulted in different surface basicity of the modified silica materials. The materials were characterized by thermogravimetry, X-ray powder diffraction, nitrogen adsorption/desorption and transmission electron microscopy. The CO2 sorption/desorption experiments performed at 25 oC by gravimetric method showed that carbon dioxide sorption capacities were 1.04mmol/g for the sample SBA-12/AP, 0.98mmol/g for the sample SBA-12/MAP and 0.68mmol/g for the sample SBA-12/PAP. The modified silica can be regenerated by purge with inert gas without heating. The fastest desorption was observed for the SBA-12/PAP silica containing amine of low basicity (pK b =8.9). The desorption process of SBA-12/AP and SBA-12/MAP samples was accompanied by consumption of heat evolved on adsorption, while no thermal effect was recorded on the DTA curve of SBA-12/PAP sample. [Copyright &y& Elsevier]

A predictive model is developed for estimating the amount of clay water and the hydration thermodynamic properties as a function of relative humidity (R.H.), for any 2:1 clay composition. From a methodology performed by Gailhanou et al. (2017) upon MX80-Na smectite, based on experimental water adsorption isotherms and structural data, a regular solid solution between anhydrous and highly hydrated clay end-members is parameterized, providing a set of 4 thermodynamic parameters Δ Cem. W H , Δ Cem. W S , W H and W S characterizing the theoretical mechanisms of adsorption of the clay water versus the relative humidity. To complete literature data, water adsorption isotherms are acquired at 25 °C and 45 °C for five natural 2:1 clays, with various compositions, interlayer charges and interlayer cations (Na, Ca, K, Mg). The amounts of clay water are extracted from the total adsorbed water amounts by removing the contribution of capillary water and the thermodynamic entities of the hydration reaction are calculated and are closely related to the nature of the clay (characterized by its interlayer and tetrahedral charges and the nature of the interlayer cation), allowing two predictive models, for di-octahedral smectites and for tri-octahedral 2:1 clays. These two models are assessed by using experimental data for other clay minerals provided by literature. For a given 2:1 clay composition, the model allows - to predict quite well the clay water adsorption isotherm, - to provide hydration thermodynamic properties (G, H, S) for the di-octahedral model and for the tri-octahedral model and-to predict the thermodynamic properties of formation for some hydrated clays of fictive compositions. Image 1 • Five natural 2:1 clays, (dioct and trioct) with various interlayer cations. • Adsorption - desorption isotherms performed at 25 °C and 45 °C. • Extraction of clay water properties from adsorption isotherms. • Prediction of the thermodynamic properties of hydration for 2:1 clays. [ABSTRACT FROM AUTHOR]