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91.
Rosana V. Pinto Sujing Wang Sergio R. Tavares Joo Pires Fernando Antunes Alexandre Vimont Guillaume Clet Marco Daturi Guillaume Maurin Christian Serre Moiss L. Pinto 《Angewandte Chemie (International ed. in English)》2020,59(13):5135-5143
Materials for the controlled release of nitric oxide (NO) are of interest for therapeutic applications. However, to date, many suffer from toxicity and stability issues, as well as poor performance. Herein, we propose a new NO adsorption/release mechanism through the formation of nitrites on the skeleton of a titanium‐based metal–organic framework (MOF) that we named MIP‐177, featuring a suitable set of properties for such an application: (i) high NO storage capacity (3 μmol mg?1solid), (ii) excellent biocompatibility at therapeutic relevant concentrations (no cytotoxicity at 90 μg mL?1 for wound healing) due to its high stability in biological media (<9 % degradation in 72 hours) and (iii) slow NO release in biological media (≈2 hours for 90 % release). The prospective application of MIP‐177 is demonstrated through NO‐driven control of mitochondrial respiration in cells and stimulation of cell migration, paving the way for the design of new NO delivery systems for wound healing therapy. 相似文献
92.
Valentin Chabert Lucille Babel Michael P. Füeg Maksym Karamash Edwin S. Madivoli Nelly Herault Joana M. Dantas Carlos A. Salgueiro Bernd Giese Katharina M. Fromm 《Angewandte Chemie (International ed. in English)》2020,59(30):12331-12336
Anaerobic microorganisms of the Geobacter genus are effective electron sources for the synthesis of nanoparticles, for bioremediation of polluted water, and for the production of electricity in fuel cells. In multistep reactions, electrons are transferred via iron/heme cofactors of c‐type cytochromes from the inner cell membrane to extracellular metal ions, which are bound to outer membrane cytochromes. We measured electron production and electron flux rates to 5×105 e s?1 per G. sulfurreducens. Remarkably, these rates are independent of the oxidants, and follow zero order kinetics. It turned out that the microorganisms regulate electron flux rates by increasing their Fe2+/Fe3+ ratios in the multiheme cytochromes whenever the activity of the extracellular metal oxidants is diminished. By this mechanism the respiration remains constant even when oxidizing conditions are changing. This homeostasis is a vital condition for living systems, and makes G. sulfurreducens a versatile electron source. 相似文献
93.
94.
Joana Antunes Quentin Gauthier Vanessa Aguiar-Pulido George Duncan Bruce McCord 《Electrophoresis》2021,42(9-10):1168-1176
Tissue-specific differentially methylated regions (tDMRs) are regions of the genome with methylation patterns that modulate gene expression in those tissue types. The detection of tDMRs in forensic evidence can permit the identification of body fluids at trace levels. In this report, we have performed a bioinformatic analysis of an existing array dataset to determine if new tDMRs could be identified for use in body fluid identification from forensic evidence. Once these sites were identified, primers were designed and bisulfite modification was performed. The relative methylation level for each body fluid at a given locus was then determined using qPCR with high-resolution melt analysis (HRM). After screening 127 tDMR's in multiple body fluids, we were able to identify four new markers able to discriminate blood (2 markers), vaginal epithelia (1 marker) and buccal cells (1 marker). One marker for each target body fluid was also tested with pyrosequencing showing results consistent with those obtained by HRM. This work successfully demonstrates the ability of in silico analysis to develop a novel set of tDMRs capable of being differentiated by real time PCR/HRM. The method can rapidly determine the body fluids left at crime scenes, assisting the triers of fact in forensic casework. 相似文献
95.
From superhydrophobic‐ to superhydrophilic‐patterned poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) architectures as a novel platform for biotechnological applications
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Vanessa F. Cardoso Ana R. Machado Vânia C. Pinto Paulo J. Sousa Gabriela Botelho Graça Minas Senentxu Lanceros‐Méndez 《Journal of Polymer Science.Polymer Physics》2016,54(18):1802-1810
The manufacture of three‐dimensional patterned electroactive poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) microstructures with tailored architecture, morphology, and wettability is presented. The patterned microstructures are fabricated using a simple, effective, low cost, and reproducible technique based on microfluidic technology. These novel structures can represent innovative platforms for advanced strategies in a wide range of biotechnological applications, including tissue engineering, drug delivery, microfluidic, and sensors and actuators devices. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1802–1810 相似文献
96.
Cordero BM Pérez Pavón JL García Pinto C Fernández Laespada ME Carabias Martínez R Rodriguez Gonzalo E 《Journal of chromatography. A》2000,902(1):195-204
An overview of the analytical applications of membrane-based systems for sample enrichment in chromatography and capillary electrophoresis is presented. A brief introduction to the different types of membranes and the main forces related to the transport through them is also given. 相似文献
97.
Several methods are being used with considerable advantage as alternatives to the Draize test, although some technical difficulties still persist. This work compared the sensitivity of HeLa and NCTC L 929 cells to evaluate the cytotoxicity of shampoos used by adults and children (undiluted and diluted to 25, 5, 1, and 0.1%), and eye drops and their containers and surfactants (diluted to 30, 10, 1, and 0.1%). Nondiluted adult shampoos and their 25 and 5% dilutions were cytotoxic for both cell lines. When diluted to 1%, only one of the shampoos was noncytotoxic, whereas among those diluted to 0.1%, only one was cytotoxic. Children's shampoos were cytotoxic when not diluted or diluted to 25%. From those diluted to 5%, only one was noncytotoxic for both cell lines. The cytotoxic tests showed that the eye drops and their containers were noncytotoxic. Surfactants were cytotoxic when diluted to 30 and 10% and noncytotoxic when diluted to 1 and 0.1%. An excellent correlation (r = 0.95) was demonstrated between the sensitivity of the HeLa and NCTC L929 cells in the evaluation of cytotoxicity reactions. 相似文献
98.
Condensation of salicylic acid and C-methylphloroglucinol gave the already known 1,3-dihydroxy-2-methylxanthone ( 1 ) along with two new compounds: 1,3-dihydroxy-4-methylxanthone ( 2 ) and a second one tentatively presented as being 1,3-dihydroxy-2-methyl-4-(2-hydroxybenzoyl)xanthone ( 3 ). The UV., IR., NMR, and mass spectra for the two first compounds are reported and their structures discussed on the basis of δ-values for H(2), H(4), CH3(4) and CH3(2). The UV. and IR. spectra for the third compound are reported too. 相似文献
99.
J. V.?Pinto M. M.?CruzEmail author R.C.?da Silva E.?Alves R.?González M.?Godinho 《The European Physical Journal B - Condensed Matter and Complex Systems》2005,45(3):331-338
The magnetic properties of Co and Ni nanosized aggregates
formed after implantation of nickel and cobalt ions in magnesium
oxide single crystals were investigated. The influence of the
implantation energy and annealing treatments was characterized. The
particle size distribution was determined from the combined analysis
of the magnetic moment dependence on both magnetic field and
temperature, and used to determine the magnetic anisotropy constant
of the aggregates. The results for nickel aggregates indicate the
presence of an antiferromagnetic layer after the annealing
treatments. 相似文献
100.
A study has been carried out on the morphology and structure of three-dimensional (3D) SiGe islands grown by molecular beam epitaxy (MBE) on Si(100) substrates. Samples of Si1-xGex alloys have been prepared to investigate the effects either of the alloy composition or of the growth temperature. Atomic force microscopy (AFM) evidenced the growth of 3D islands and transmission electron microscopy (TEM) demonstrated wetting layer growth on Si(100), independently on the deposition conditions. Energy dispersive spectroscopy (EDS) micro-analyses carried out on cross-sections of large Si1-xGex islands with defects allowed a measurement of the Ge distribution in the islands. To the best of our knowledge, these have been the first experimental evidences of a composition change inside SiGe islands. The interpretation of the experimental results has been done in terms of strain-enhanced diffusion mechanisms both of the growing species (Si and Ge) and of small islands. 相似文献