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61.
Antonio Ieni Valeria Barresi Rosario Caltabiano Alessia Caleo Luca Reggiani Bonetti Salvatore Lanzafame Pio Zeppa Rosario Alberto Caruso Giovanni Tuccari 《International journal of molecular sciences》2014,15(12):22331-22341
Background: The assessment of human epidermal growth factor receptor 2 (HER2) gene amplification is essential in order to identify those patients affected by advanced gastric cancer who may benefit from Trastuzumab targeted therapy. Materials and Methods: With the aim to investigate the concordance rate in HER2 status between primary gastric carcinoma (GC) and synchronous lymphnode metastases, we investigated HER2 status in a cohort of 108 surgical formalin-fixed paraffin-embedded specimens of GC and matched synchronous metastatic lymph nodes collected from three different units of Anatomic Pathology in southern of Italy. Fleiss-Cohen weighted k statistics were used to assess the concordance rate of HER2 status. Results: HER2 amplification was observed in 17% of primary GCs and the overall concordance rate with corresponding nodal metastases was 90.74%. Changes in HER2 status between primary GC and matched synchronous metastases were evidenced in 10 (9.26%) cases. Of these, 6 cases were HER2 amplified in the primary GC and not amplified in the metastases, while 4 were HER2 not amplified in the primary tumour and amplified in the lymph node metastases. Conclusions: Although at present the simultaneous determination of HER2 in advanced gastric cancer and corresponding metastatic lymph nodes is not mandatory, the possibility that the synchronous metastases of GC have a different HER2 status from that of the primary tumour is of remarkable significance; Indeed this may have influence on the therapeutic management and prognosis of the patients. 相似文献
62.
Tiziana Nardo Valeria Chiono Piergiorgio Gentile Maryam Tabrizian Gianluca Ciardelli 《国际聚合物材料杂志》2016,65(14):741-750
Poly(DL-lactide-co-ε-caprolactone) (PLCL) and poly(DL-lactide-co-glycolide) (PLGA) blends of various compositions were prepared. Fractured sections of PLCL/PLGA blends did not evidence phase separation and blend glass transition temperatures suggested some degree of blend compatibility. The elastic modulus showed a negative deviation from the additive law of mixture. Superior biocompatibility in terms of fibroblast NIH 3T3 cell adhesion and proliferation, better mechanical properties, and a more homogeneous phase were obtained with PLCL/PLGA 25/75 blend. Rapid degradation of PLCL phase (4–8 weeks) in PLCL/PLGA 25/75 blend led to a porous structure, which makes it a potential candidate for drug delivery systems. 相似文献
63.
Mariana Pinteala Valeria Harabagiu Cornelia Cotzur Marian N. Holerca Bogdan C. Simionescu 《Polymer Bulletin》1994,32(2):173-178
Summary Carboxyester- and carboxyamido-terminated polydimethylsiloxanes were obtained through the reaction of cyclic anhydrides (succinic, maleic and phthalic anhydride) with hydroxypropyl- and aminoalkyl-terminated polydimethylsiloxanes, respectively. The reactivity of the starting compounds and the influence of the reaction conditions on the characteristics of the final products are discussed.Part 1: Eur. Polym. J., in press 相似文献
64.
Ian W Hamley Valeria Castelletto Nágila MPS Ricardo Maria EN Pinho Colin Booth David Attwood Zhuo Yang 《Polymer International》2007,56(1):88-92
Small‐angle X‐ray scattering was used to characterise aqueous micellar gels of triblock copolymers E137S18E137, E82S9E82, E76S5E76, E62P39E62, and of two mixtures: E137S18E137 and E62P39E62 (Mix 1) and E82S9E82 and E62P39E62 (Mix 2), each 50/50 wt%. E = oxyethylene, CH2CH2O; S = oxyphenylethylene, OCH2CH(C6H5); and P = oxypropylene, OCH2CH(CH3). Within the concentration and temperature ranges investigated (30–40 wt% copolymer, 20–80 °C), spherical micelles of copolymers E137S18E137, E82S9E82 and E62P39E62 packed into body‐centred cubic (BCC) structures. Gels of E76S5E76 were stable only at high concentrations and low temperatures, and a 70 wt% copolymer solution at T = 30 °C formed a hexagonal gel consistent with cylindrical micelles. It is likely that the mixed copolymers would form two distributions of micelles, and more complex structures were expected. However, gels of Mix 2 had well‐ordered BCC structures, while the less ordered gels of Mix 1 were also best characterised as BCC. Copyright © 2006 Society of Chemical Industry 相似文献
65.
Giovanni Bolelli Johannes Rauch Valeria Cannillo Andreas Killinger Luca Lusvarghi Rainer Gadow 《Materials Letters》2008,62(17-18):2772-2775
High-Velocity Suspension Flame Spraying (HVSFS) has recently emerged as a potential alternative to conventional HVOF-spraying: employing liquid suspensions instead of dry powder feedstock enables the use of very fine grain-sized particles, resulting in small-sized lamellae. Thin, low-porosity coatings can thus be manufactured. This paper details the first attempt at manufacturing glass coatings using the HVSFS technique: these coatings can have multiple applications (anti-corrosion coatings on metal and ceramic substrates, bio-compatible coatings, etc). A CaO–ZrO2–SiO2 glass frit was selected for this attempt. Excellent potentialities emerged (very low porosity), but some problems still existed (big “droplet-like” features on the coating surface), which have recently been largely overcome thanks to process modifications. 相似文献
66.
Lorena?del?Rosario Cappellari Maricel?Valeria?Santoro Herminda?Reinoso Claudia?Travaglia Walter?Giordano Erika?BanchioEmail author 《Journal of chemical ecology》2015,41(2):149-158
Plant growth-promoting rhizobacteria (PGPR) generally exert their effects through enhancement of plant nutrient status and/or phytohormone production. The effects of PGPR on aromatic plant species are poorly known. We measured plant growth parameters, chlorophyll content, trichome density, stomatal density, and levels of secondary metabolites in peppermint (Mentha piperita) seedlings inoculated with PGPR strains Bacillus subtilis GB03, Pseudomonas fluorescens WCS417r, P. putida SJ04, or a combination of WCS417r?+?SJ04. The treated plants, in comparison with controls, showed increases in shoot biomass, root biomass, leaf area, node number, trichome density, and stomatal density, and marked qualitative and quantitative changes in monoterpene content. Improved knowledge of the factors that control or affect biosynthesis of secondary metabolites and monoterpene accumulation will lead to strategies for improved cultivation and productivity of aromatic plants and other agricultural crops without the use of chemical fertilizers or pesticides. 相似文献
67.
Thioether Analogues of Disulfide‐Bridged Cyclic Peptides Targeting Death Receptor 5: Conformational Analysis,Dimerisation and Consequences for Receptor Activation 下载免费PDF全文
Dr. Karolina Pulka‐Ziach Dr. Valeria Pavet Neila Chekkat Dr. Karine Estieu‐Gionnet Roman Rohac Dr. Marie‐Charlotte Lechner Dr. Cristian R. Smulski Dr. Gabrielle Zeder‐Lutz Dr. Danièle Altschuh Dr. Hinrich Gronemeyer Prof. Dr. Sylvie Fournel Dr. Benoit Odaert Dr. Gilles Guichard 《Chembiochem : a European journal of chemical biology》2015,16(2):293-301
Cyclic peptides containing redox‐stable thioether bridges might provide a useful alternative to disulfide‐bridged bioactive peptides. We report the effect of replacing the disulfide bridge with a lanthionine linkage in a 16‐mer cyclic peptide that binds to death receptor 5 (DR5, TRAIL‐R2). Upon covalent oligomerisation, the disulfide‐bridged peptide has previously shown similar behaviour to that of TNF‐related apoptosis inducing ligand (TRAIL), by selectively triggering the DR5 cell death pathway. The structural and biological properties of the DR5‐binding peptide and its desulfurised analogue were compared. Surface plasmon resonance (SPR) data suggest that these peptides bind DR5 with comparable affinities. The same holds true for dimeric versions of these peptides: the thioether is able to induce DR5‐mediated apoptosis of BJAB lymphoma and tumorigenic BJELR cells, albeit to a slightly lower extent compared to its disulfide homologue. NMR analysis revealed subtle variation in the conformations of the two peptides and suggests that the thioether peptide is slightly less folded than its disulfide homologue. These observations could account for the different capability of the two dimers to cluster DR5 receptors on the cell surface and to trigger apoptosis. Nevertheless, our results suggest that the thioether peptide is a potential candidate for evaluation in animal models. 相似文献
68.
Cesira Pasquarella Licia Veronesi Giorgio Liguori Christian Napoli Ida Torre Valeria Di Onofrio Carola Tinteri SItI working group "Hygiene in Dentistry 《The Science of the total environment》2010,408(19):4045-4051
The dental practice is associated with a high risk of infections, both for patients and healthcare operators, and the environment may play an important role in the transmission of infectious diseases. A microbiological environmental investigation was carried out in six dental clinics as a pilot study for a larger multicentre study that will be performed by the Italian SItI (Society of Hygiene, Preventive Medicine and Public Health) working group "Hygiene in Dentistry". Microbial contamination of water, air and surfaces was assessed in each clinic during the five working days of the week, before and during treatments. Air and surfaces were also examined at the end of the daily activity. A wide variation was found in microbial environmental contamination, both within the participating clinics and relative to the different sampling times. Microbial water contamination in Dental Unit Water Systems (DUWS) reached values of up to 26 × 104 cfu/mL (colony forming units per millilitre). P. aeruginosa was found in 33% of the sampled DUWS and Legionella spp. in 50%. A significant decrease in the Total Viable Count (TVC) was recorded during the activity. Microbial air contamination showed the highest levels during dental treatments and tended to decrease at the end of the working activity (p < 0.05). Microbial buildup on surfaces increased significantly during the working hours. As these findings point out, research on microbial environmental contamination and the related risk factors in dental clinics should be expanded and should also be based on larger collections of data, in order to provide the essential knowledge aimed at targeted preventive interventions. 相似文献
69.
Efficient and stable nitritation and denitritation of ammonium-rich sludge dewatering liquor using an SBR with continuous loading 总被引:3,自引:0,他引:3
Separate treatment of dewatering liquor from anaerobic sludge digestion significantly reduces the nitrogen load of the main stream and improves overall nitrogen elimination. Such ammonium-rich wastewater is particularly suited to be treated by high rate processes which achieve a rapid elimination of nitrogen with a minimal COD requirement. Processes whereby ammonium is oxidised to nitrite only (nitritation) followed by denitritation with carbon addition can achieve this. Nitrogen removal by nitritation/denitritation was optimised using a novel SBR operation with continuous dewatering liquor addition. Efficient and robust nitrogen elimination was obtained at a total hydraulic retention time of 1 day via the nitrite pathway. Around 85-90% nitrogen removal was achieved at an ammonium loading rate of 1.2 kg [corrected] NH(4)(+)-N m(-3)d(-1). Ethanol was used as electron donor for denitritation at a ratio of 2.2 g COD g(-1) N removed. Conventional nitritation/denitritation with rapid addition of the dewatering liquor at the beginning of the cycle often resulted in considerable nitric oxide (NO) accumulation during the anoxic phase possibly leading to unstable denitritation. Some NO production was still observed in the novel continuous mode, but denitritation was never seriously affected. Thus, process stability can be increased and the high specific reaction rates as well as the continuous feeding result in decreased reactor size for full-scale operation. 相似文献