Novel Styrylpyridines as Probes for SPECT Imaging of Amyloid Plaques
ABSTRACT We report a series of radioiodinated styrylpyridines as single photon emission computed tomography probes for imaging Abeta plaques in the brain of patients with Alzheimer's disease (AD). In vitro binding showed that all of the styrylpyridines displayed very good binding affinities in postmortem AD brain homogenates (Ki = 3.6 to 15.5 nM). No-carrier-added samples of 13a, 13b, 16a, 16b, and 16e (radioiodinated with 125I) were successfully prepared. The in vivo biodistribution in normal mice, at 2 min after injection, showed excellent initial brain penetrations (4.03, 6.22, 5.43, and 8.04% dose/g for [125I]13a, 13b, 16a, and 16b, respectively). Furthermore, in vitro autoradiography of AD brain sections showed that the high binding signal was specifically due to the presence of Abeta plaques. Taken together, these results strongly suggest that these styrylpyridines are useful for imaging Abeta plaques in the living human brain.
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ABSTRACT: This paper describes a new approach to the evaluation of loss adjustment factors for distribution systems. Such factors are required for `use of system' and wheeling calculations and reflect the amount by which purchases of energy at entry points to the system must exceed consumption at the point of use to account for the losses which occur in between. Renewed interest in cost-reflective methods of charging for losses has resulted from the deregulation of the electricity supply industry in many parts of the world. An algorithm is described which combines the use of graph theory with readily available load flow results, to assign the losses in each line or transformer within the system to the consumers supplied by it. The resulting allocation is shown to account for the voltage level, location and consumption pattern of the consumer in a way which is economically efficient. A variety of strategies for apportioning losses between multiple consumers at a given location can be implemented. The algorithm is suitable for allocating both demand and energy losses. Results on a full size distribution network are presented, and are compared with traditional published loss adjustment factorsPower Industry Computer Application Conference, 1995. Conference Proceedings., 1995 IEEE; 06/1995
Article: Nuclear medicine in psychiatry.Nuclear medicine review. Central & Eastern Europe: journal of Bulgarian, Czech, Macedonian, Polish, Romanian, Russian, Slovak, Yugoslav societies of nuclear medicine and Ukrainian Society of Radiology 02/2007; 10(2):116-24.
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ABSTRACT: Through the development and application of a unique approach for producing Re-metallopeptides, a new class of peptide-derived probes that are designed to target beta-amyloid plaques was developed. Derivatives of a class of beta-breaker peptides having the core sequence lvffa or affvl (lower case letters represent D-amino acids) and the single amino acid chelate quinoline (SAACQ) ligand which can bind Re and (99m)Tc were prepared on an automated peptide synthesizer. Both monomeric and dimeric peptides were synthesized in modest to good yields where in select examples a biotin-containing amino acid derivative was included to act as a linker point for further conjugation to carrier proteins. The Re complexes for all reported peptides were prepared similarly and screened for their ability to inhibit fibrillogenesis. Two of the reported compounds showed excellent inhibitory properties (8a: 40 +/- 5% amyloid formation versus control; 16: 40 +/- 4%) and warrant further investigation. For one of these leads, the (99m)Tc analogue was synthesized and the product showed high stability toward histidine and cysteine challenges, making it a viable candidate for in vivo biodistribution studies.Bioconjugate Chemistry 06/2008; 19(5):1087-94. DOI:10.1021/bc800001g · 4.82 Impact Factor