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The aim of this study was the synthesis and structural characterization of SiO2–Al2O3 microspheres with SiO2 core and (100 − x)Al2O3·xFe2O3 (x = 0, 5, and 10 mol%) shell. Smooth spherical silica particles of uniform size around 1 μm have been synthesized as core material based on the Stober method. In order to enhance the specific surface area, the silica particles were coated with a thin nanostructurated shell, about 15 nm, of aluminum and iron oxides (100 − x)Al2O3·xFe2O3 (x = 0, 5, and 10 mol%). The embedding of iron oxide in the covering shell was related to potential applications of these composite biomaterials for contrast enhancement in magnetic resonance imaging (MRI) and at the same time for local treatments of cancer by hyperthermia. The XRD results point out the amorphous structure of the obtained core–shell particles. The TEM images evidence continuous shell coating of silica spherical microparticles and the XPS analysis of the surfaces prove the occurrence of iron oxide on the outermost layer of the microspheres. Both FTIR and XPS results evidence the formation of Al–O–Si linkage proving that Al2O3 and SiO2 are chemically bonded in the investigated core–shell microspheres.

Three active cellulose-based papers coated in chitosan (P-CH), chitosan-TiO2 (P-CH-TiO2) and chitosan-Ag/TiO2 (P-CH-Ag/TiO2), respectively were real-time aged for 6 months at 4°C, 55% relative humidity, 15 h light/9 h dark cycle and characterized in relation to plain paper (P). The reduction in the chitosan cristallinity, N-deacetylation of chitosan, degradation of cellulosic fibers and loss in the active agents (proven by SEM, FTIR, EDX techniques and physical-chemical-microbial measurements) occurred during storage explains the deterioration of the barrier and antimicrobial properties of the active papers and subsequently the decrease in their preservation efficiency. Experimental results indicate that after storage for 6 months of the clarified butter the most effective package was P-CH-Ag/TiO2 for which the lowest levels of PV (2.72 mEq O2/kg), yeasts and molds (5.8 CFU/g) and E. coli (6.12 CFU/g) counts were measured. By mathematical modeling of the evolution of the PV, E. coli, yeasts and molds experimental profiles the shelf-life of the clarified butter packed in P, P-CH, P-CH-TiO2 and P-CH-Ag/TiO2 was assessed in respect to their admitted limits to 1.6, 2, 4 and 9.3 months, respectively. At the end of storage the appearance of P-CH-Ag/TiO2 package was clean, without greasy spots, as opposed to that of P, P-CH and P-CH-TiO2, which proves its self-cleaning property.

Human skeletal remains may be considered bio-archives due to their particular combination of mechanical, structural, and chemical properties that render natural resistance against post-mortem degradation of ancient biomolecules. The survival of organic matter in ancient tissues is of great interest due to its potential in recovering information on the historical past of individuals and populations including health, dietary history, ancestry, and migration patterns. Even though the ancient biomolecules have become a powerful research tool, the archeogenetic research field can often deal with obstacles regarding the limited availability of osteological material and/or ethical concerns as their analysis is destructive. Here, we describe an alternative, efficient method for simultaneous extraction of DNA and proteins from the same archeological sample source, thus limiting the damage to valuable ancient human skeletal remains. The proposed method consists of overnight decalcification of powdered tissue, purification and concentration of biomolecules, and separation of the resulting solution for subsequent DNA purification and protein precipitation. Its performance was assessed relative to previously described approaches, comparing the concentration of the retrieved biomolecules. Our results show that this method designed to co-purify DNA and proteins is appropriate to obtain authentic sequences of the human mitochondrial control region from medieval or more recent human teeth. Also, the resulting proteins can be used for immunochromatographic detection of malaria in skeletal material suspect of infection with Plasmodium sp.

Three active cellulose-based papers coated with chitosan (P–CH), chitosan–TiO2 nanocomposite (P–CH–TiO2) and chitosan–Ag/TiO2 nanocomposite (P–CH–Ag/TiO2), respectively, were subjected to real-time ageing for 6 months at 25 °C and 45% re humidity and characterized from a physical–chemical–antimicrobial perspective in relation to plain paper (P). Scanning electron microscopy pictures indicate a smooth morphology in the active papers, while the structure of P is rough with large pores. The fresh papers containing nanocomposites displayed enhanced barrier properties against water vapor, air and grease. The photocatalytic action of TiO2 during ageing results in the deacetylation of the chitosan layer and the degradation of cellulosic fibers with a reduction of barrier properties. Fresh P–CH–Ag/TiO2 displayed the highest value of inhibition index against yeasts and molds (95.65%), its value decreasing to 79.25% after 6-month storage. Walnut kernels were stored for 6 months at 25 °C and 45% RH in packages made of investigated papers and analyzed. It was found that P–CH–Ag/TiO2 is the most effective in the prolongation of the shelf-life of kernels. They are assessed to be safe in terms of peroxide value and yeasts and molds count for 11.6 and 15.1 months when stored in P–CH–Ag/TiO2 filled with 25 and 50 g kernels, respectively, as compared to 1.8 and 3.4 months, respectively when they are stored in P. The appearance of packages containing nanocomposites was clean without grease spots in opposition with that of P and P–CH and proves the self-cleaning property of P–CH–TiO2 and P–CH–Ag/TiO2. Cluster diagrams indicate a strong correlation between the quality and safety of kernels and properties of paper sheets in a paper type-depending manner.

New silica-based particles embedding iron were synthesized following a freeze-drying-assisted sol–gel route. The samples were preliminary characterized in view of potential applications as theranostic magnetic resonance imaging (MRI) contrast agents and for hyperthermia treatment. The structural changes induced by iron addition were studied by X-ray diffraction, Fourier transform infrared and electron paramagnetic resonance spectroscopies. The addition of Fe2O3 impedes the SiO2 crystallization denoting that iron plays, in this case, the role of a glass network stabilizer. The composition on surface and nearby was analyzed by X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy both before and after samples immersion in simulated body fluid. The results suggest the nominal composition with 5 mol% Fe2O3 added to 0.7SiO2∙0.3Na2O matrix of interest for further investigations as potential MRI contrast agent and hyperthermia vector.

IF 2.673; International audience; ObjectiveTo evaluate the natural history of MEN1-related bronchial endocrine tumors (br-NETs) and to determine their histological characteristics, survival and causes of death.Summary background databr-NETs frequency ranges from 3 to 13% and may reach 32% depending on the number of patients evaluated and on the criteria required for diagnosis.MethodsThe 1023-patient series of symptomatic MEN1 patients followed up in a median of 48.7 [35.5–59.6] years by the Groupe d’étude des Tumeurs Endocrines was analyzed using time-to-event techniques.Resultsbr-NETs were found in 51 patients (4.8%, [95% CI 3.6–6.2%]) and were discovered by imaging in 86% of cases (CT scan, Octreoscan, Chest X-ray, MRI). Median age at diagnosis was 45 years [28–66]. Histological examination showed 27 (53%) typical carcinoids (TC), 16 (31%) atypical carcinoids (AC), 2 (4%) large cell neuroendocrine carcinomas (LCNEC), 3(6%) small cell neuroendocrine carcinomas (SCLC), 3(6%) TC associated with AC. Overall survival was not different from the rest of the cohort (HR 0.29, [95% CI 0.02–5.14]). AC tended to have a worse prognosis than TC (p = 0.08). Seven deaths were directly related to br-NETs (three AC, three SCLC and one LCNEC). Patients who underwent surgery survived longer (p = 10−4) and were metastasis free, while 8 of 14 non-operated patients were metastatic. There were no operative deaths.ConclusionsAround 5% of MEN1 patients develop br-NETs. br-NETs do not decrease overall survival in MEN1 patients, but poorly differentiated and aggressive br-NETs can cause death. br-NETs must be screened carefully. A biopsy is essential to operate on patients in time.

This study addresses the preparation and characterization of three active cellulose-based papers containing TiO2, Ag–TiO2 and Ag–TiO2–zeolite nanocomposites (P–TiO2, P–Ag–TiO2, P–Ag–TiO2–Z) and is aimed at use in bread packaging. It is organized in two parts: (1) the first part covers the morpho-structural characterization of nanocomposites and paper sheets (X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, energy dispersive X-ray) and explores some properties of the papers sheets (photocatalytic activity, wettability, barrier properties); (2) in the second part, the comparative efficiency of papers in the bread storage is discussed in terms of acidity, nutritional parameters (total fat, proteins and carbohydrates) and yeasts and molds charge. Morpho-structural investigations revealed a heterogeneous distribution of nanocomposites in the cellulose network as single particles or agglomerates. The higher content of active agents in the P–Ag–TiO2–Z positively affects the hydrophobicity, roughness, photocatalytic activity, opacity and water vapor permeability the most as compared to P–P (plain paper), P–TiO2 and P–Ag–TiO2. The free channels inside the zeolite structure result in the poorest barrier properties against air and grease of P–Ag–TiO2–Z and the highest food simulants–paper contact angles. Packaging tests indicate P–Ag–TiO2 as the most effective in the preservation of nutritional compounds in the bread. In return, P–Ag–TiO2–Z prolongs the microbiological safety of bread in terms of yeasts and molds content for 10 days at 20 °C and 12 days at 4 °C, 2 days longer than the second-ranked P–Ag–TiO2.

Different morphologies of TiO2 photoelectrodes for dye sensitized solar cells were obtained by using TiO2 gels dried in normal conditions (TiO2 amb) and in CO2 atmosphere at high pressure (TiO2 press). After a subsequent calcination, the powders were processed as pastes and drop-casted on conductive glass in order to prepare photoanodes for dye sensitized solar cells. N719 commercial dye was used as sensitizer in all the experiments. The structure and morphology of the processed TiO2 materials were investigated via X-ray diffraction, scanning electron microscopy, transmission electron microscopy and N2 adsorption/desorption measurements. The dye adsorption capacity of the photoanodes was tested using ultraviolet-visible absorption spectroscopy. The photovoltaic performances of the dye sensitized solar cells were investigated using current/voltage curves (I/V), open circuit photovoltage decay measurements and electrochemical impedance spectroscopy. The conversion efficiency (η) and short circuit density (Jsc) for TiO2 amb were 1.90 % and 5 mA/cm2 respectively, while the TiO2 press cell exhibited a 40 and 50 % increase in Jsc and η values respectively. This was correlated with increased dye loading capacities due to a broader distribution of pore size towards the mesopore region.

Early medical diagnostic in nanomedicine requires the implementation of innovative nanosensors with highly sensitive, selective, and reliable biomarker detection abilities. In this paper, a dual Localized Surface Plasmon Resonance - Surface Enhanced Raman Scattering (LSPR- SERS) immunosensor based on a flexible three-dimensional (3D) gold (Au) nanocups platform has been implemented for the first time to operate as a relevant “proof-of-concept” for the specific detection of antigen-antibody binding events, using the human IgG - anti-human IgG recognition interaction as a model. Specifically, polydimethylsilane (PDMS) elastomer mold coated with a thin Au film employed for pattern replication of hexagonally close-packed monolayer of polystyrene nanospheres configuration has been employed as plasmonic nanoplatform to convey both SERS and LSPR readout signals, exhibiting both well-defined LSPR response and enhanced 3D electromagnetic field. Synergistic LSPR and SERS sensing use the same reproducible and large-area plasmonic nanoplatform providing complimentary information not only on the presence of anti-human IgG (by LSPR) but also to identify its specific molecular signature by SERS. The development of such smart flexible healthcare nanosensor platforms holds promise for mass production, opening thereby the doors for the next generation of portable point-of-care devices.

Well-defined calcium molybdate (CaMoO4) and hydroxyapatite (HAP) nanocrystals were developed by thermal treatment on the surface of a SiO2–CaO–P2O5–MoO3 amorphous precursor synthesised at room-temperature by sol–gel route. The structural and morphological characterisaions were performed by several techniques: energy dispersive X-ray spectroscopy, thermal analyses (DTA/TGA), X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy, electron paramagnetic resonance. Complementary, Fourier transform infrared and Raman spectroscopies provided a clear picture regarding the short range order structure, emphasising beside the CaMoO4 phase development, the presence of HAP nanocrystals. The vibrational spectroscopic techniques proved to be valuable tools for evidencing very small HAP nanocrystallites that cannot be clearly observed by XRD and TEM analyses.

The synthesis procedure represents a key aspect in designing the physical and chemical properties of gold nanoparticles. The current study proposes a simple approach for gold nanoparticles synthesis using non-thermal plasma. The novelty of the setup consists in producing an in-liquid plasma discharge in argon bubbles that are externally generated in the solution exposed to treatment. Because plasma is the source of active species which are directly involved in gold reduction, no additional reducing agent was necessary. Collagen protein was used as capping agent. A plasma treatment of 10 min is sufficient for obtaining stable colloidal solutions with UV-Vis absorption maximum at 530 nm. Transmission electron microscopy images revealed preponderant spherical nanoparticles with dimensions in the range of 6–20 nm. The method of synthesis distinguishes by its good reproducibility, facility, efficiency, and ability to generate stable colloidal nanoparticles after several minutes of plasma exposure.

Background The development of novel biomaterials able to control cell activities and direct their fate is warranted for engineering functional bone tissues. Adding bioactive materials can improve new bone formation and better osseointegration. Three types of titanium (Ti) implants were tested for in vitro biocompatibility in this comparative study: Ti6Al7Nb implants with 25% total porosity used as controls, implants infiltrated using a sol–gel method with hydroxyapatite (Ti HA) and silicatitanate (Ti SiO2). The behavior of human osteoblasts was observed in terms of adhesion, cell growth and differentiation. Results The two coating methods have provided different morphological and chemical properties (SEM and EDX analysis). Cell attachment in the first hour was slower on the Ti HA scaffolds when compared to Ti SiO2 and porous uncoated Ti implants. The Alamar blue test and the assessment of total protein content uncovered a peak of metabolic activity at day 8–9 with an advantage for Ti SiO2 implants. Osteoblast differentiation and de novo mineralization, evaluated by osteopontin (OP) expression (ELISA and immnocytochemistry), alkaline phosphatase (ALP) activity, calcium deposition (alizarin red), collagen synthesis (SIRCOL test and immnocytochemical staining) and osteocalcin (OC) expression, highlighted the higher osteoconductive ability of Ti HA implants. Higher soluble collagen levels were found for cells cultured in simple osteogenic differentiation medium on control Ti and Ti SiO2 implants. Osteocalcin (OC), a marker of terminal osteoblastic differentiation, was most strongly expressed in osteoblasts cultivated on Ti SiO2 implants. Conclusions The behavior of osteoblasts depends on the type of implant and culture conditions. Ti SiO2 scaffolds sustain osteoblast adhesion and promote differentiation with increased collagen and non-collagenic proteins (OP and OC) production. Ti HA implants have a lower ability to induce cell adhesion and proliferation but an increased capacity to induce early mineralization. Addition of growth factors BMP-2 and TGFβ1 in differentiation medium did not improve the mineralization process. Both types of infiltrates have their advantages and limitations, which can be exploited depending on local conditions of bone lesions that have to be repaired. These limitations can also be offset through methods of functionalization with biomolecules involved in osteogenesis.