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101.
Malay Patra Larissa S. Eichenberger Gregor Fischer Jason P. Holland 《Angewandte Chemie (International ed. in English)》2019,58(7):1928-1933
Monoclonal antibodies (mAbs), immunoglobulin fragments, and other proteins are important scaffolds in the development of radiopharmaceuticals for diagnostic immuno‐positron emission tomography (immuno‐PET) and targeted radioimmunotherapy (RIT). Conventional methods for radiolabelling proteins with metal ions such as 68Ga, 64Cu, 89Zr, and 90Y require multi‐step procedures involving pre‐purification, functionalisation with a chelate, and subsequent radiolabelling. Standard coupling chemistries are time‐consuming, difficult to automate, and involve synthesis, isolation, and storage of an intermediate, new molecular entity (the conjugated mAb) whose biochemical properties can differ from those of the parent protein. To circumvent these issues, we developed a photoradiochemical approach that uses fast, chemoselective, light‐induced protein modification under mild conditions with novel metal‐ion‐binding chelates derivatised with aryl azide (ArN3) groups. Experiments show that one‐pot photochemical conjugation and radiolabelling of formulated mAbs can be achieved in <20 min. 相似文献
102.
Zhou X Espy-Wilson CY Boyce S Tiede M Holland C Choe A 《The Journal of the Acoustical Society of America》2008,123(6):4466-4481
Speakers of rhotic dialects of North American English show a range of different tongue configurations for /r/. These variants produce acoustic profiles that are indistinguishable for the first three formants [Delattre, P., and Freeman, D. C., (1968). "A dialect study of American English r's by x-ray motion picture," Linguistics 44, 28-69; Westbury, J. R. et al. (1998), "Differences among speakers in lingual articulation for American English /r/," Speech Commun. 26, 203-206]. It is puzzling why this should be so, given the very different vocal tract configurations involved. In this paper, two subjects whose productions of "retroflex" /r/ and "bunched" /r/ show similar patterns of F1-F3 but very different spacing between F4 and F5 are contrasted. Using finite element analysis and area functions based on magnetic resonance images of the vocal tract for sustained productions, the results of computer vocal tract models are compared to actual speech recordings. In particular, formant-cavity affiliations are explored using formant sensitivity functions and vocal tract simple-tube models. The difference in F4/F5 patterns between the subjects is confirmed for several additional subjects with retroflex and bunched vocal tract configurations. The results suggest that the F4/F5 differences between the variants can be largely explained by differences in whether the long cavity behind the palatal constriction acts as a half- or a quarter-wavelength resonator. 相似文献
103.
O'Dell LA Gunawidjaja PN Holland MA Mountjoy G Pickup DM Newport RJ Smith ME 《Solid state nuclear magnetic resonance》2008,33(1-2):16-24
The HfO2-SiO2 system is attracting interest as a possible new dielectric material in semiconductor devices. Knowledge of the location of hafnium within the silica network and the effect hafnium has on the structure will be central to the successful use of this material system in this application. Here, sol-gel techniques have been used to manufacture (HfO2)x(SiO2)1-x samples (x=0.1, 0.2 and 0.4, each heat treated at 250, 500 and 750 degrees C) and these have been characterised by magic angle spinning (MAS) NMR (1H, 13C, 17 O, 29Si), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis. 29Si MAS NMR showed that increasing the hafnia content decreases the connectivity of the silicate network, i.e. increases the range of differently connected SiO4 (Qn) units with more having increased numbers of non-bridging oxygens (i.e. lower n). FTIR and 17 O MAS NMR showed unequivocally that the x=0.4 sample phase-separated at higher temperatures, while in the x=0.1 sample the hafnium was homogeneously mixed into the SiO2 phase without any phase separation. 相似文献
104.
105.
Jason P. Holland Melanie Gut Simon Klingler Rachael Fay Amaury Guillou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(1):33-48
The ability to modify biologically active molecules such as antibodies with drug molecules, fluorophores or radionuclides is crucial in drug discovery and target identification. Classic chemistry used for protein functionalisation relies almost exclusively on thermochemically mediated reactions. Our recent experiments have begun to explore the use of photochemistry to effect rapid and efficient protein functionalisation. This article introduces some of the principles and objectives of using photochemically activated reagents for protein ligation. The concept of simultaneous photoradiosynthesis of radiolabelled antibodies for use in molecular imaging is introduced as a working example. Notably, the goal of producing functionalised proteins in the absence of pre-association (non-covalent ligand-protein binding) introduces requirements that are distinct from the more regular use of photoactive groups in photoaffinity labelling. With this in mind, the chemistry of thirteen different classes of photoactivatable reagents that react through the formation of intermediate carbenes, electrophiles, dienes, or radicals, is assessed. 相似文献
106.
High‐Frequency Fe–H Vibrations in a Bridging Hydride Complex Characterized by NRVS and DFT 下载免费PDF全文
Dr. Vladimir Pelmenschikov Dr. Leland B. Gee Dr. Hongxin Wang Dr. K. Cory MacLeod Sean F. McWilliams Dr. Kazimer L. Skubi Prof. Dr. Stephen P. Cramer Prof. Dr. Patrick L. Holland 《Angewandte Chemie (International ed. in English)》2018,57(30):9367-9371
High‐spin iron species with bridging hydrides have been detected in species trapped during nitrogenase catalysis, but there are few general methods of evaluating Fe?H bonds in high‐spin multinuclear iron systems. An 57Fe nuclear resonance vibrational spectroscopy (NRVS) study on an Fe(μ‐H)2Fe model complex reveals Fe?H stretching vibrations for bridging hydrides at frequencies greater than 1200 cm?1. These isotope‐sensitive vibrational bands are not evident in infrared (IR) spectra, showing the power of NRVS for identifying hydrides in this high‐spin iron system. Complementary density functional theory (DFT) calculations elucidate the normal modes of the rhomboidal iron hydride core. 相似文献
107.
This paper describes the use of the terephthalate dosimeter to measure the threshold and extent of cavitation arising from medical ultrasound sources at high frequencies. Significant hydroxyl radical production was noted from a physiotherapy source and low level activity was also detected when using a pulsed, diagnostic type transducer system. The effect of sound intensity and the type of field is described. The possibility of using polymer degradation to monitor the cavitation is also discussed. 相似文献
108.
A. Juliard J. Ledrut E. B. Holland G. M. Gilligan H. F. Bradley M. G. Roeder S. G. Clarke und B. S. Evans 《Fresenius' Journal of Analytical Chemistry》1930,79(5-6):205-207
Ohne Zusammenfassung 相似文献
109.
Cadmium phosphate glasses, of general formula xCdO(1−x)P2O5 (0.25?x?0.6), have been prepared by melting in alumina crucibles, with resulting dissolution of up to 6.4 mol% Al2O3. The local structure in these glasses has been studied using 31P, 27Al and 113Cd nuclear magnetic resonance. The distribution of [PO4]Qn species as a function of composition has been shown to follow the simple binary model. The rate of change of the chemical shift of the 31P species in the Q2 environment depends on the bond order, which in turn reflects the extent of double bonding between phosphorus and oxygen. 相似文献
110.