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121.
Lidija Androš Dubraja Damir Pajić Martina Vrankić Jure Dragović Matjaz Valant Metka Benčina Marijana Jurić 《Journal of the American Ceramic Society》2019,102(11):6697-6704
Chromium niobate and tantalate (CrNbO4 and CrTaO4) were synthesized by pyrolysis of the oxalate-based heterometallic complexes [Cr2(bpy)4(μ-O)4Nb2(C2O4)4]·3H2O (Cr-Nb) and [Cr(bpy)2(H2O)(μ-O)Ta(C2O4)3]2·3.5H2O (Cr-Ta) (bpy = 2,2'-bipyridine). Compared to conventional solid-state synthesis, herein studied oxides are prepared at lower temperatures, in one step without repeating grinding procedures. The structure, morphology, and optical properties of the as-synthesized oxides were characterized using powder X-ray diffraction (PXRD), field emission scanning electron microscopy (SEM), the thermogravimetric and differential thermal analysis (TG/DTA) and UV-vis diffuse reflectance spectroscopy (UV-vis DRS). The determined band gap energies of CrNbO4 and CrTaO4 are 2.39 and 2.82 eV, respectively, which prompted us to investigate photocatalytic activity of these oxides in degradation of dyes. Microscopy studies show that the particles of both oxides began to aggregate into bigger particles, leading to an increase in grain size. Additionally, magnetization measurements on both oxides revealed spin-glass behavior at low temperatures. 相似文献
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123.
Evaluation of standard and new chromogenic selective plating media for isolation and identification of Bacillus cereus 总被引:2,自引:0,他引:2
Fricker M Reissbrodt R Ehling-Schulz M 《International journal of food microbiology》2008,121(1):27-34
In this study, the performance of two new chromogenic plating media (CBC and BCM) was compared with two standard selective plating media (PEMBA and MYP) recommended by food authorities for isolation, identification and enumeration of Bacillus cereus. The four media types were challenged with a strain set comprising 100 B. cereus isolates from different origins and with different toxigenic potentials (40 food isolates, 40 isolates from food borne outbreaks and 20 clinical isolates). Additionally, the performance of the plating media for analysis of complex samples was assessed using naturally contaminated foods. Our survey showed that the new chromogenic media represent a good alternative to the conventional standard media. Especially, if laboratory staff are not highly trained in identification of B. cereus, the conventional media could lead to substantial misidentification and underestimation of food borne illness caused by B. cereus. However, there are some B. cereus strains that could not even be detected with this new type of chromogenic media. After the fatal misidentification of a highly toxic strain, other methods for a conclusive identification of B. cereus are needed. Sequence analysis of the plcR gene, a pleiotropic regulator of various virulence factors and B. cereus specific enzymes, revealed a significant correlation between atypical colony appearance and specific variances within the plcR gene sequences of those strains. The current concept of selective plating media, utilising PlcR regulated enzyme activities for differentiation purposes, should therefore be reconsidered and research should be geared towards culture independent methods. 相似文献
124.
Intermittent agitation strategies have been increasingly used for a range of process development applications, i.e., to modulate physical cues, to improve stem cell differentiation yields, and to control hydrodynamic shear stresses in microcarrier suspension; however, there is a distinct lack of characterization. Both continuous and intermittent agitation modes in relation to suspension and mixing dynamics within a DASGIP bioreactor were characterized. Suspension dynamics were found to be affected by microcarrier porosity and the degree of settling was found to be more pronounced at the top of the bioreactor. Mixing time characterization showed a marked improvement in mixing efficiency for intermittent agitation, with an overall dependence on the timing of tracer insertion. 相似文献
125.
Arianna Giacomini Sara Taranto Sara Rezzola Sara Matarazzo Elisabetta Grillo Mattia Bugatti Alessia Scotuzzi Jessica Guerra Martina Di Trani Marco Presta Roberto Ronca 《International journal of molecular sciences》2020,21(24)
Lung cancer represents an extremely diffused neoplastic disorder with different histological/molecular features. Among the different lung tumors, non-small-cell lung cancer (NSCLC) is the most represented histotype, characterized by various molecular markers, including the expression/overexpression of the fibroblast growth factor receptor-1 (FGFR1). Thus, FGF/FGFR blockade by tyrosine kinase inhibitors (TKi) or FGF-ligand inhibitors may represent a promising therapeutic approach in lung cancers. In this study we demonstrate the potential therapeutic benefit of targeting the FGF/FGFR system in FGF-dependent lung tumor cells using FGF trapping (NSC12) or TKi (erdafitinib) approaches. The results show that inhibition of FGF/FGFR by NSC12 or erdafitinib induces apoptosis in FGF-dependent human squamous cell carcinoma NCI-H1581 and NCI-H520 cells. Induction of oxidative stress is the main mechanism responsible for the therapeutic/pro-apoptotic effect exerted by both NSC12 and erdafitinib, with apoptosis being abolished by antioxidant treatments. Finally, reduction of c-Myc protein levels appears to strictly determine the onset of oxidative stress and the therapeutic response to FGF/FGFR inhibition, indicating c-Myc as a key downstream effector of FGF/FGFR signaling in FGF-dependent lung cancers. 相似文献
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127.
Monoclonal antibody‐targeted polymeric nanoparticles for cancer therapy – future prospects 下载免费PDF全文
Stephen Goodall Martina L. Jones Stephen Mahler 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2015,90(7):1169-1176
Although combination therapy for cancer utilising monoclonal antibodies in conjunction with chemotherapeutic drugs has resulted in increases in 5 year survivals, there nevertheless remains significant morbidity and mortality associated with systemic delivery of cytotoxic drugs. The advent of living radical polymerisation has resulted in complex and elegant nanoparticle structures that can be engineered to passively target a drug payload for cancer treatment. This presents a therapeutic modality whereby biodistribution and consequently systemic toxicity can be reduced, while focusing drug delivery to the tumour site. Nanoparticle delivery can be enhanced by attachment of a targeting monoclonal antibody fragment to facilitate tumour cell uptake through endocytosis, and so increase therapeutic efficacy. In this way, monoclonal antibodies can be supercharged by carrying a payload consisting of a cocktail of conventional chemotherapeutic drugs and siRNA. This review will focus on antibody‐targeted polymeric nanoparticles to cancer cells, and methods and technologies for synthesising such antibody‐targeted nanoparticles. The review is confined to polymeric‐based nanoparticles as these offer some advantages over liposomal nanoparticles and may circumvent some of the pitfalls in nanomedicine. Development of these antibody based polymeric nanoparticles and future directions for therapy are highlighted in this review. © 2014 Society of Chemical Industry 相似文献
128.
Alessandro Sannino Dr. Elena Gabriele Martina Bigatti Dr. Sara Mulatto Dr. Jacopo Piazzi Dr. Jörg Scheuermann Prof. Dr. Dario Neri Dr. Etienne J. Donckele Dr. Florent Samain 《Chembiochem : a European journal of chemical biology》2019,20(7):955-962
DNA-encoded chemical libraries are often used for the discovery of ligands against protein targets of interest. These large collections of DNA-barcoded chemical compounds are typically screened by using affinity capture methodologies followed by PCR amplification and DNA sequencing procedures. However, the performance of individual steps in the selection procedures has been scarcely investigated, so far. Herein, the quantitative analysis of selection experiments, by using three ligands with different affinity to carbonic anhydrase IX as model compounds, is described. In the first set of experiments, quantitative PCR (qPCR) procedures are used to evaluate the recovery and selectivity for affinity capture procedures performed on different solid-phase supports, which are commonly used for library screening. In the second step, both qPCR and analysis of DNA sequencing results are used to assess the recovery and selectivity of individual carbonic anhydrase IX ligands in a library, containing 360 000 compounds. Collectively, this study reveals that selection procedures can be efficient for ligands with sub-micromolar dissociation constants to the target protein of interest, but also that selection performance dramatically drops if 104 copies per library member are used as the input. 相似文献
129.
130.
Claudio Baiocchi Martina Magni Francesco Romaniello Emanuele Forte Mauro Fontana 《Journal of the American Oil Chemists' Society》2020,97(10):1057-1069
Nominal sorbitan tristearate (E492) commercial samples are widely used generally as emulsifiers and particularly as anti-bloom agents in confectionery products. In spite of this generalized use, their qualitative and quantitative evaluation is poorly documented in literature and the relative works go back to the last decades of last century. In the present work, a deep study by HPLC-High Resolution Mass Spectrometry of qualitative composition of five E492 commercial samples was made up showing a very complex pattern of stearic and palmitic acid esters with the sorbitol anhydrides, sorbitan, and isosorbide. A clear distinction of sorbitan mono-, di-, tri-, and tetra-esters, of sorbitol penta- and hexa-esters and isosorbide mono- and di-esters was achieved. Contemporarily, difference in the qualitative pattern between E492 commercial samples coming from different suppliers was established. As a consequence, quantitative evaluation can be reliably obtained by using as calibration standard the same E492 present in real samples. The accuracy and recovery of the method were determined allowing in this way a reliable application to commercial confectionery products. The detailed knowledge of STS composition may be of great help to orient the synthesis conditions in order to modulate its properties as a function of various experimental necessities. 相似文献