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The 18F-labelled amino acid derivative 3-O-methyl-6-[18F]fluoro-l-DOPA ([18F]OMFD) is a potential radiotracer for imaging tumour tissue using positron emission tomography. The precursor N-formyl-3-O-methyl-4-O-boc-6-trimethyl-stannyl-l-DOPA-ethyl ester enables direct electrophilic radiofluorination by stereoselective destannylation. After partial hydrolysis, optimized HPLC purification and sterile filtration, the [18F]OMFD obtained with high radiochemical purity and ready for use. The total synthesis time is about 50 min and the radiochemical yield achieved is 20–25% (decay corrected, related to [18F]F2). It was demonstrated that [18F]OMFD could be produced routinely and reliably for clinical use. [18F]FDOPA-preparation devices can be used with minor modifications. [Copyright &y& Elsevier]

Abstract: The ignition behavior of single bubbles during the first oscillation after a shock wave impact was investigated experimentally. The bubbles were created by injection of oxygen into liquid cyclohexane. High speed pressure and optical measurements were applied. The experiments were performed inside cyclohexane, at room temperature and at an initial pressure of 1bar. It was found that an incident shock wave with a peak pressure of 85bar 8.5bar can ignite bubbles with equivalent initial diameters between 2.4 and 7.2mm. Measurements related to the shock-induced bubble compression process, the jet formation inside the bubble, the ignition delay, the light illumination during the bubble explosion, as well as other aspects of the observed bubble behavior are presented. In addition to the experimental observations a theoretical analysis is presented. The set of equations for the theoretical estimation of the pressure and the temperature and of the gaseous mixture inside the bubble at the moment of the observed bubble ignitions is shown and explained. [Copyright &y& Elsevier]

Abstract: The bifunctional chelating agent 2-[4,7-bis(2-pyridylmethyl)-1,4,7-triazacyclononan-1-yl]acetic acid, DMPTACN-COOH, has been found to bind strongly to copper(II), resulting in a radiocopper(II)-ligand complex that exhibits high in vivo stability. The pendant carboxylic acid group enables this derivative to be conjugated to the N-terminal amino acid residues of peptides. Exploiting this, two stabilized bombesin (BBN) derivatives, βAla-βAla-[Cha13,Nle14]BBN(7–14) and βhomo-Glu-βAla-βAla-[Cha13,Nle14]BBN(7–14) have been coupled to DMPTACN-COOH and radiolabeled with the positron emitter copper-64 (64 Cu-1 and 64 Cu-3). The in vitro binding characteristics of the [64Cu]Cu-labeled bombesin conjugates in gastrin-releasing peptide receptor (GRPR) over-expressing prostate cancer (PC-3) cells have been evaluated. Biodistribution studies performed in Wistar rats indicate a specific uptake in the GRPR-rich pancreas and rapid renal elimination for both 64 Cu-1 and 64 Cu-3. Small animal PET imaging studies performed in NMRI nu/nu mice bearing the human prostate tumor PC-3 demonstrated a very high degree of tumor accumulation for 64 Cu-1 and 64 Cu-3. Incorporation of a single additional glutamic acid residue within the spacer between bombesin and the radiolabeled complex (64 Cu-3) leads to a higher tumor-to-muscle uptake ratio (amounting to >30 at 100 min post injection) compared to 64 Cu-1. [Copyright &y& Elsevier]

Abstract: In this work the production of 64Cu via the 64Ni(p,n)64Cu reaction with optimized conditions for low current irradiation is presented. Different target setups and cleaning steps for lowering metal contaminations in the product were applied. 64Cu with high specific activities up to 1685GBq/μmol was produced despite low overall activity (∼4.2GBq per run). The module processing leads to a highly reproducible, reliable product quality (<1μg Cu and <7μg Ni). Besides its diagnostic value 64Cu may be of interest even for therapeutic purposes due to its decay characteristics. [Copyright &y& Elsevier]

Abstract: The synthesis and structure–activity relationship of a new class of indole derivatives with low-nanomolar affinity for the SERT and high selectivity versus the 5-HT1A receptor were recently reported. Based on their chemical structure, four new indolylpropylamine derivatives which contain atoms to afford future labeling with PET isotopes, were synthesized and evaluated as SERT ligands. The chemistry of these novel derivatives, their biological evaluation, the general method of preparing the precursor indole for labeling, and the C-11 labeling of the most promising indole derivative, are described herein. [Copyright &y& Elsevier]

Abstract: An approach to synthesize the electrophilic fluorinating agent no-carrier-added (n.c.a.) [18F]perchloryl fluoride ([18F]FClO3) in superacidic media in the presence of KClO4 or anhydrous perchloric acid starting from [18F]fluoride was demonstrated in this study. However, the radiochemical yields were low (1–6%) and poorly reproducible. Fluorosulphonic acid proved to be an essential intermediate as revealed by non-radioactive experiments. A key problem in the preparation of [18F]FClO3 is the assumed kinetic inhibition due to the unfavourable stoichiometric ratio of the ClO4 moiety to [18F]HSO3F. [Copyright &y& Elsevier]

Based on a high affinity to the enzyme estrone sulfatase (ES), 16α-[18F]fluoroestradiol-3,17β-disulfamate ([18F]FESDS) has been suggested as a potential PET radiotracer for imaging steroid-dependent breast tumours. The distribution of [18F]FESDS was studied in rats, tumour-bearing nude mice and piglets. In all species evidence for binding to a second target, the enzyme carbonic anhydrase (CA), was obtained. ES and CA inhibitors significantly reduced the radiotracer uptake in various organs but not in tumours. It is concluded that [18F]FESDS binds to ES and CA in vivo but this binding is not strong enough to allow tumour imaging with positron emission tomography (PET). [Copyright &y& Elsevier]

16α-Fluoroestradiol-3,17β-disulfamate (FESDS) strongly inhibits estrone sulfatase (ES), an enzyme which is also present in the brain. The enzyme is probably involved in important regulatory functions of neurosteroids which may be disturbed in certain brain diseases. In the present study, [18F]FESDS was used to measure the amount of ES in various rat brain regions using quantitative in vitro autoradiography. The obtained values vary between 0.29 pmol (mg protein)–1 (pons) and 11.5 pmol (mg protein)–1 (striatum). They are positively correlated with the enzyme activity measured in homogenates of the corresponding regions. Because this radiotracer binds also to carbonic anhydrase in the brain it is only of limited use for in vivo imaging studies. [Copyright &y& Elsevier]

A modified method for the synthesis of the intermediate product N-Boc-3,4-di(Boc-O)-6-iodo-L-phenylalanine ethyl ester of the [18F]FDOPA precursor preparation was developed. With the application of bis-(trifluoroacetoxy)-iodobenzene for the iodination step with elemental iodine the yield of the intermediate can be increased from 12% to 50–60%. By replacing silica-gel-based RP HPLC column by a polymer-based column for semi-preparative purification of [18F]FDOPA from the reaction mixture the radiochemical purity of the final product can be increased up to >99%. For the determination of the radiochemical impurity [18F]fluoride a HPLC method using a column with polymer-based RP material was introduced. [Copyright &y& Elsevier]

• Comparison of refurbishment costs from different data sources. • Detailed representation of existing building stocks and possible renovation intensities. • Development of two types of energy saving cost curves: marginal and average costs. • Highly influencing factors on renovation costs per savings identified. • High amounts of heat savings could be cost effective in all analysed countries. Around 25% of final energy consumption in the European Union is currently used for space heating. The potential for reducing this demand through renovation of existing buildings is very significant and recognised to be an important factor for reaching CO 2 reduction targets. In this analysis we develop two types of cost curves for heat savings in buildings in 6 European countries. This is based on a detailed representation of the existing building stocks and an analysis and comparison of costs and effects of refurbishment actions for several levels of heat savings in each representative building in these countries. We find that the costs for reaching savings of 40–60% are remarkably cheaper than for reaching higher savings and that the highest and cheapest savings are located in buildings that are still not renovated. We also find the following highly influencing factors on the costs of renovation measures: the share of window area in the envelope, the surface-to-volume ratio and the current heat demand. The results of this work can be further used to investigate cost optimal levels of heat savings versus heat supply in order to draw the right decisions on the way to an efficient and low CO 2 energy system. [ABSTRACT FROM AUTHOR]