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71.
The synthesis of a new spiroether is described. The title compound is obtained as a diastereomeric mixture in 45% yield. 相似文献
72.
The success of positron emission tomography (PET) in personalised medicine and drug development requires radioisotopes that provide high quality images and flexible chemistry for a broad application. 64Cu is arguably one of the most suitable PET isotopes for imaging with the evolving target agents, but there are not many appropriate chelating agents for 64Cu and this has limited its wider application. The bi-functional chelator, SarAr is known to bind 64Cu2+ quantitatively (i.e. one metal per ligand present) and rapidly (<2 min) at 10(-6) M over a range of pH (4-9). In this paper the conjugation of SarAr to the whole and fragmented antibody is described. Conjugation of the SarAr to the protein does not impair its coordination of the 64Cu. It complexes the 64Cu2+ rapidly, quantitatively and essentially irreversibly at pH 5. Animal studies show that the 64Cu-SarAr-immunoconjugates maintain their specificity for the target and are stable in vivo. Also, SarAr is a platform technology, is easy to use in a kit formulation and is readily adaptable for the wider application in 64Cu PET imaging. 相似文献
73.
Fillaux F Romain F Limage MH Leygue N 《Physical chemistry chemical physics : PCCP》2006,8(37):4327-4336
We compare Raman and infrared spectra of the nuOH/OD modes in benzoic acid crystal powders at 7 K. The extremely sharp Raman bands contrast to the broad infrared profiles and suggest adiabatic separation of hydrogen (deuterium) dynamics from the crystal lattice. There is no evidence of any proton-proton coupling term. The assignment scheme is consistent with a quasisymmetric double-minimum potential, largely temperature independent. Tunnel splitting is a major band shaping mechanism, in addition to anharmonic coupling with lattice modes. The proton/deuteron dynamics are rationalized with nonlocal pseudoparticles and extended states. We propose a symmetry-related damping mechanism to account for the broad infrared profiles, as opposed to the sharp Raman bands. We assign spectral features to distinct interconversion mechanisms based on either pseudoparticle transfer or adiabatic pairwise transfer. We establish close contacts with theoretical models based on first-principles calculations. 相似文献
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Gold nanoparticles have strong and tunable absorption peaks in their optical extinction spectra, a phenomenon that has recently been exploited to generate localized heating in the vicinity of these particles. However the optimum particle geometry and illumination regime to maximize these effects appears not to have been previously examined in any detail. Here we show that the interplay between the particles' absorption cross-sections, volume, and surface area lead to there being specific conditions that can maximize particle temperature and surface heat flux. Optical absorption efficiencies were calculated from the formulation of Mie, and radiative, convective, and conductive heat transfer models were used to model the thermal performance of particles in different situations. Two technologically relevant scenarios for illumination, namely, irradiation by sunlight at 800 W/m2 and by a monochromatic laser source of 50 kW/m2 tuned to the peak absorption wavelength, were considered. For irradiation by sunlight, the resultant heat flux is optimized for an 80 nm diameter nanoshell with an aspect ratio of 0.8, while for irradiation by laser the maximum heat flux is found for 50 nm nanoshells, with an aspect ratio of 0.9. 相似文献
76.
Alexandre Boulay Sophie Laine Nadine Leygue Eric Benoist Sophie Laurent Luce Vander Elst Robert N. Muller Béatrice Mestre-Voegtle Claude Picard 《Tetrahedron letters》2013
In the design of dual-imaging probes, the first functionalized and neutral heterobimetallic Re(I)–Gd(III) complex, highly soluble in aqueous solutions, has been prepared. This system exhibits interesting photophysical properties (λem = 578 nm, ? = 1.4%) for optical imaging and substantial higher relaxivity (r1 = 6.6 mM−1 s−1 at 0.47 T and 37 °C) than the clinically used MRI contrast agents. Moreover, this system incorporates an aromatic ester functionality suitable for bioconjugation. 相似文献
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79.
Nowadays, long wait, cancellations and resource overload frequently occur in healthcare, especially in those sectors related to the patients passing through the operating theatre in both United States and the European Union. Since more and more hospitals seek to develop the overall patient pathways instead of the effectiveness of “isolated” departments, the most important work has been defining suitable patient groups for employing process management and simulation tools developed in the recent decades. In this study, we proposed a data mining method, an auto-stopped Bisecting K-Medoids clustering algorithm, to classify patients into groups with homogenous trajectories. This method classifies the patient trajectories with two stages. At the first stage, patients are classified by the complexity of outpatient visits; afterwards, the groups obtained at the first stage are further classified by the original information of the trajectories where all medical appointments including outpatient ones are taken into account. By using a real data set collected from a medium-size Belgian hospital, we demonstrate how the proposed approach works and examine which kinds of trajectories are grouped into the same clusters. According to the experimental results, the proposed method can be used to classify patients into manageable groups with homogenous trajectories, which can be used as a base for the process modelling techniques and simulation tools. 相似文献
80.
Greta Petrella Camilla Montesano Sara Lentini Giorgia Ciufolini Domitilla Vanni Roberto Speziale Andrea Salonia Francesco Montorsi Vincenzo Summa Riccardo Vago Laura Orsatti Edith Monteagudo Daniel Oscar Cicero 《Molecules (Basel, Switzerland)》2021,26(14)
A new strategy that takes advantage of the synergism between NMR and UHPLC–HRMS yields accurate concentrations of a high number of compounds in biofluids to delineate a personalized metabolic profile (SYNHMET). Metabolite identification and quantification by this method result in a higher accuracy compared to the use of the two techniques separately, even in urine, one of the most challenging biofluids to characterize due to its complexity and variability. We quantified a total of 165 metabolites in the urine of healthy subjects, patients with chronic cystitis, and patients with bladder cancer, with a minimum number of missing values. This result was achieved without the use of analytical standards and calibration curves. A patient’s personalized profile can be mapped out from the final dataset’s concentrations by comparing them with known normal ranges. This detailed picture has potential applications in clinical practice to monitor a patient’s health status and disease progression. 相似文献