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81.
Maria Cristina Cassani Francesca Gambassi Barbara Ballarin Daniele Nanni Ilaria Ragazzini Davide Barreca Chiara Maccato Antonietta Guagliardi Norberto Masciocchi Alessandro Kovtun Katia Rubini Elisa Boanini 《RSC advances》2021,11(33):20429
A copper-based metal–organic framework (MOF) was prepared using a new linker, a 5-substituted isophthalic acid bearing a propargyl carbamate group, intended to provide a terminal alkyne function protruding from the material surface to generate supported gold species for potential catalytic applications. The novel material was fully characterized by spectroscopic analyses of different kinds: FTIR, Raman, EDX, and XPS, as well as by thermal and surface area measurements. Synchrotron X-ray diffraction data analysis, in particular, revealed that this MOF, labelled [Cu(1,3-YBDC)]·xH2O (x ∼ 2), where Y stands for the pendant alkYne and BDC for benzene dicarboxylate, contains a complex network of 5-substituted isophthalate anions bound to Cu(ii) centers, arranged in pairs within paddlewheel (or “Chinese lantern”) fragments of Cu2(μ-COO)4(D)2 formulation (D being a neutral Lewis base), with a short Cu⋯Cu distance of 2.633(4) Å. Quite unexpectedly, the apical atom in the paddlewheel structure belongs to the carbamate carbonyl oxygen atom. Such extra coordination by the propargyl carbamate groups drastically reduces the MOF porosity, a feature that was also confirmed by BET measurements. However, the MOF functionality is retained at the external crystal surface where 2% of active terminal alkynes is located.A copper-based metal–organic framework with a novel 5-substituted isophthalic linker bearing a propargyl carbamate group protruding from the material surface. 相似文献
82.
The current study presents the electron beam melting (EBM) efficiency of copper technogenic material with high impurity content (Se, Te, Pb, Bi, Sn, As, Sb, Zn, Ni, Ag, etc.) by means of thermodynamic analysis and experimental tests. On the basis of the calculated values of Gibbs free energy and the physical state of the impurity (liquid and gaseous), a thermodynamic assessment of the possible chemical interactions occurring in the Cu-Cu2O-Mex system in vacuum in the temperature range 1460–1800 K was made. The impact of the kinetic parameters (temperature and refining time) on the behaviour and the degree of removal of impurities was evaluated. Chemical and metallographic analysis of the obtained ingots is also discussed. 相似文献
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84.
Marina de Tommaso Marianna La Rocca Silvia Giovanna Quitadamo Katia Ricci Giusy Tancredi Livio Clemente Eleonora Gentile Elena Ammendola Marianna Delussi 《The journal of headache and pain》2022,23(1)
BackgroundThe discovery of the prominent action of Calcitonin Gene Related Peptide –CGRP- on trigeminal afferents and meningeal vessels, opened a new era in migraine treatment. However, how the block of nociceptive afferents could act on central mechanisms of migraine is still not clear. In this pilot study we aimed to test the effect of 3 months Galcanezumab (CGA) therapy on occipital visual reactivity in migraine patients, using the Steady State Visual Evoked Potentials-SSVEPs and Functional Near Infrared Spectroscopy –fNIRS.MethodThirteen migraine patients underwent clinical and neurophysiological examination in basal condition (T0), 1 h after GCA injection (T1) and after 3 months of GCA treatment (T2). Ten healthy volunteers were also evaluated.ResultsAt T2, there was a reduction of headache frequency and disability. At T2, the EEG power significantly diminished as compared to T0 and T1 at occipital sites, and the topographical analysis confirmed a restoration of SSVEPs within normal values. The Oxyhemoglobin levels in occipital cortex, which were basically increased during visual stimulation in migraine patients, reverted to normal values at T2.ConclusionsThe present pilot study indicates that Galcanezumab could act on cortical targets located beyond the pain network, restoring the abnormal occipital reactivity. This effect could indicate the possible disease modifying properties of CGRP related monoclonal antibodies. 相似文献
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86.
Katia Herz Alexandra Becker Chenyue Shi Masatsugo Ema Satoru Takahashi Michael Potente Michael Hesse Bernd K. Fleischmann Daniela Wenzel 《Angiogenesis》2018,21(2):349-361
Endothelial cell proliferation is a key process during vascular growth but its kinetics could only be assessed in vitro or ex vivo so far. To enable the monitoring and quantification of cell cycle kinetics in vivo, we have generated transgenic mice expressing an eGFP-anillin construct under control of the endothelial-specific Flt-1 promoter. This construct labels the nuclei of endothelial cells in late G1, S and G2 phase and changes its localization during the different stages of M phase, thereby enabling the monitoring of EC proliferation and cytokinesis. In Flt-1/eGFP-anillin mice, we found eGFP+ signals specifically in Ki67+/PECAM+ endothelial cells during vascular development. Quantification using this cell cycle reporter in embryos revealed a decline in endothelial cell proliferation between E9.5 to E12.5. By time-lapse microscopy, we determined the length of different cell cycle phases in embryonic endothelial cells in vivo and found a M phase duration of about 80 min with 2/3 covering karyokinesis and 1/3 cytokinesis. Thus, we have generated a versatile transgenic system for the accurate assessment of endothelial cell cycle dynamics in vitro and in vivo. 相似文献
87.
Fernanda Neves de Carvalho Carolina Toniolo Zenatti Danila Cassia Reis Santana Juliana Maria da Silva Juliane Cristina Oliveira dos As Katia Kisielow dos Anjos Jessica Sigari Cassia de Lima Santos Marcelle Guerra Olivia Pereira Barros Tomaz Cochemore Roberto Camargo Narciso Mario Lucio Baptista Filho 《The Brazilian journal of infectious diseases》2018
88.
Katia Abarca Isabel Ibánez Cecilia Perret Pablo Vial Jean-Antoine Zinsou 《International journal of infectious diseases》2008,12(3):270-277
OBJECTIVES: To compare the immunogenicity, safety, and interchangeability of two pediatric hepatitis A vaccines, Avaxim 80U-Pediatric and Havrix 720, in Chilean children. METHODS: In this randomized trial, 332 hepatitis A virus (HAV) seronegative children from 1 to 15 years of age received two doses of Avaxim, two doses of Havrix, or Havrix followed by Avaxim, 6 months apart. Anti-HAV antibody titers were measured before and 14 days after the first dose of vaccine, and before and 28 days after the second dose of vaccine. Immediate reactions were monitored; reactogenicity was evaluated from parental reports. RESULTS: Seroconversion rates after the first vaccination were 99.4% and 100% for Avaxim and Havrix, respectively. Anti-HAV geometric mean concentrations (GMCs) were 138 mIU/ml for Havrix (95% confidence interval (CI): 120; 159) and 311 mIU/ml for Avaxim (95% CI: 274; 353). GMCs increased to 4008 mIU/ml after two doses of Havrix, 8537 mIU/ml following two doses of Avaxim, and 7144 mIU/ml in children who received Havrix with Avaxim as the second dose. Following the first injection, 36% of subjects given Avaxim and 44% given Havrix reported local reactions; 38% of subjects in the Avaxim group and 40% in the Havrix group reported systemic reactions related to vaccination. Solicited reactions were less frequent after the second dose of Avaxim or Havrix, occurring in 27% to 37% of subjects. CONCLUSIONS: No significant difference in seroconversion rates was seen 14 days after a single dose of vaccine. A two-dose schedule with either vaccine or with Havrix/Avaxim provided a strong booster response. Both vaccines were well tolerated and can be recommended for routine vaccination of Chilean children. Avaxim 80 may be used to complete a vaccine schedule begun with Havrix 720. 相似文献
89.
Thierry Atzeni Chantal Henry Isabelle Minois Sébastien Gard Alain Desage Léa Zanouy Katia M'Bailara 《Psychiatry research》2013
To better explore the clinical heterogeneity of bipolar mood states, we developed a dimensional scale for assessing all mood episodes (depressive, hypomanic, manic, mixed states) using the same tool. The Multidimensional Assessment of Thymic States (MATHYS) (Henry et al., 2008) provides two scores, a total score measuring a level of activation and a sub-score of emotional reactivity. The aim of this study was to establish the appropriate cut-off in total activation versus inhibition and in the emotional reactivity sub-score in bipolar disorders. Patients (n=187) during an acute episode and controls (n=89) filled in the MATHYS. Receiver Operating Characteristic (ROC) curves were obtained to estimate the sensitivity and specificity of the global score and the emotional reactivity sub-score of the MATHYS, in order to differentiate patients from controls. ROC curves showed very satisfactory sensitivity and specificity levels both for the total score and the sub-score of emotional reactivity, thus providing an appropriate cut-off. Concerning the total score between 0 and 200, patients with a score lower than 91 had significant global inhibition and those with a score higher than 109 had significant global activation. Regarding the emotional reactivity sub-score between 0 and 40, patients with a score lower than 16 had significant emotional hyporeactivity and those with a score higher than 24 had significant emotional hyperreactivity. Our results provide cut-offs for the MATHYS to identify patients in an acute phase. 相似文献
90.
Does treatment have an impact on incidence and risk factors for autism spectrum disorders in children with infantile spasms? 下载免费PDF全文