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He underwent an [ SP 18 sp F]PSMA-1007 PET/CT in the context of biochemical recurrence (PSA 4.5 ng/ml) and continuous low back pain, with a negative abdominal CT and bone scintigraphy. To our knowledge, this is the first case in which nLSP is extensively visible on [ SP 18 sp F]PSMA-1007 PET/CT, stressing the importance of the knowledge of the neuroanatomy to detect this common though often more subtle spread of prostate cancer. [Extracted from the article]

Guidelines that summarize the views of the European Association of Nuclear Medicine Neuroimaging Committee regarding brain tumor imaging using radiolabelled amino acid analogues are presented. The guidelines' purpose is to aid the nuclear medicine practitioners in recommending the diagnostic impact of this technique in neuro-oncological practice.

A comparative study was carried out on two promising presynaptic dopamine transporter single-photon emission tomography (SPECT) radioligands with a fast pharmacokinetic profile, 123I-FP-β-CIT (FP) and 99mTc-TRODAT-1 (TR), in order to assess their differential diagnostic power in early parkinsonism and their sensitivity for detection of disease progression. This cross-sectional study was conducted on 96 patients with early-stage parkinsonism referred in a tertiary clinical setting. Mean disease duration was 2.0±1.3 years, and patients had a modified Hoehn and Yahr (H&Y) stage of 1–2 (average 1.2). Forty-seven patients received TR, and 49 received FP. In both groups, ten patients with normal presynaptic function were included as a control population; all other patients were clinically diagnosed as having idiopathic Parkinson’s disease. Groups were matched for gender, age, disease duration and modified H&Y stage. Triple-head gamma camera SPECT was analysed using a semiquantitative index of transporter binding (BI). Discriminant analysis with cross-validation resulted in a maximal classification accuracy for FP of 93% (sensitivity 95% and specificity 86%) for the contralateral putamen BI. For TR, the corresponding values were 87% accuracy, 92% sensitivity and 70% specificity. For FP, disease duration was correlated with both the putamen BI (-8.8%/year, ρ=-0.41, P=0.025) and the putamen/caudate ratio (-7.4%/year, ρ=-0.51, P=0.004), but for TR no significant correlation was found (all P values >0.5). In conclusion, both FP and TR show high sensitivity in a clinically relevant setting, but FP has superior accuracy for early differential diagnosis of idiopathic parkinsonism and non-degenerative extrapyramidal disorders, as well as better sensitivity for disease follow-up. [ABSTRACT FROM AUTHOR]

A prospective pilot trial was performed in 20 patients randomised to receive either [sup 131]I-Lipiodol therapy alone (n=10) or [sup 131]I-Lipiodol combined with a short low-dose cisplatin infusion (n=10), the aim being to evaluate the possible positive influence of a radiosensitiser on toxicity and tumour response. An activity of 1,354-2,128 MBq (mean 1,824 MBq) [36.6-57.5 mCi (mean 49.3 mCi)] [sup 131]I-labelled Lipiodol was administered by selective instillation in the hepatic artery. Cisplatin was given in a dose of 30 mg/m² at day -1 and day +6 (day 0: [sup 131]I-Lipiodol). The primary endpoint of this trial was toxicity of therapy; points of secondary interest were tumour response and survival at 6 months. With the use of cisplatin we found a higher percentage of stable or diminished tumour size (90%, vs 40% without). A benefit in group survival at 6 months was not evident. Lowgrade stomatitis in one patient and minor changes in peripheral blood count were probably directly related to cisplatin, but its administration is unlikely to be associated with an excess of serious side-effects. The use of lowdose cisplatin infusion as a radiosensitising agent in [sup 131]ILipiodol therapy for hepatocellular carcinoma seems safe and may be beneficial for tumour control. Larger patient groups are necessary for confirmation and to establish the future role of [sup 131]I-Lipiodol in hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

Bifidobacterium adolescentis, a gram-positive saccharolytic bacterium found in the human colon, can, alongside other bacteria, utilise stachyose in vitro thanks to the production of an α-galactosidase. The enzyme was purified from the cell-free extract of Bi. adolescentis DSM 20083T. It was found to act with retention of configuration (α→α), releasing α-galactose from p-nitrophenyl galactoside. This hydrolysis probably operates with a double-displacement mechanism, and is consistent with the observed glycosyltransferase activity. As α-galactosides are interesting substrates for bifidobacteria, we focused on the production of new types of α-galactosides using the transgalactosylation activity of Bi. adolescentisα-galactosides. Starting from melibiose, raffinose and stachyose oligosaccharides could be formed. The transferase activity was highest at pH 7 and 40 °C. Starting from 300 mM melibiose a maximum yield of 33% oligosaccharides was obtained. The oligosaccharides formed from melibiose were purified by size-exclusion chromatography and their structure was elucidated by NMR spectroscopy in combination with enzymatic degradation and sugar linkage analysis. The trisaccharide α- d-Gal p-(1 → 6)-α- d-Gal p-(1 → 6)- d-Glc p and tetrasaccharide α- d-Gal p-(1 → 6)-α- d-Gal p-(1 → 6)-α- d-Gal p-(1 → 6)- d-Glc p were identified, and this indicates that the transgalactosylation to melibiose occurred selectively at the C-6 hydroxyl group of the galactosyl residue. The trisaccaride α- d-Gal p-(1 → 6)-α- d-Gal p-(1 → 6)- d-Glc p formed could be utilised by various intestinal bacteria, including various bifidobacteria, and might be an interesting pre- and synbiotic substrate. [ABSTRACT FROM AUTHOR]

Two novel arabinofuranohydrolases (AXH-d3 and AXH-m23) were purified from Bifidobacterium adolescentis DSM 20083. Both enzymes were induced upon growth of Bi. adolescentis on xylose and arabinoxylan-derived oligosaccharides. They were only active with arabinoxylans and therefore denoted as arabinoxylan arabinofuranohydrolases. Their optimal activity was at pH 6 and 30–40 °C. They were very specific in their mode of action and were clearly different from AXH-m from Aspergillus awamori. AXH-m23 released only arabinosyl groups, which were linked to the C-2 or C-3 position of singly substituted xylose residues in arabinoxylan oligomers. AXH-d3 hydrolysed C-3-linked arabinofuranosyl residues of doubly substituted xylopyranosyl residues of arabinoxylans and arab- inoxylan-derived oligosaccharides. No activity was observed with C-2-linked arabinofuranosyl residues of these doubly substituted xylopyranosyl residues, or against C-2- and C-3-linked arabinofuranosyl residues of singly substituted xylopyranosyl residues. The combination of AXH-d3 and AXH-m showed low debranching activity with highly substituted glucurono-arabinoxylans. However, arabinoxylan from wheat flour was debranched almost completely. [ABSTRACT FROM AUTHOR]

Background: Fully integrated PET/MR systems are being used frequently in clinical research and routine. National Electrical Manufacturers Association (NEMA) characterization of these systems is generally done with 18F which is clinically the most relevant PET isotope. However, other PET isotopes, such as 68Ga and 90Y, are gaining clinical importance as they are of specific interest for oncological applications and for follow-up of 90Y-based radionuclide therapy. These isotopes have a complex decay scheme with a variety of prompt gammas in coincidence. 68Ga and 90Y have higher positron energy and, because of the larger positron range, there may be interference with the magnetic field of the MR compared to 18F. Therefore, it is relevant to determine the performance of PET/MR for these clinically relevant and commercially available isotopes. Methods: NEMA NU 2–2007 performance measurements were performed for characterizing the spatial resolution, sensitivity, image quality, and the accuracy of attenuation and scatter corrections for 18F, 68Ga, and 90Y. Scatter fraction and noise equivalent count rate (NECR) tests were performed using 18F and 68Ga. All phantom data were acquired on the GE Signa integrated PET/MR system, installed in UZ Leuven, Belgium. Results: 18F, 68Ga, and 90Y NEMA performance tests resulted in substantially different system characteristics. In comparison with 18F, the spatial resolution is about 1 mm larger in the axial direction for 68Ga and no significative effect was found for 90Y. The impact of this lower resolution is also visible in the recovery coefficients of the smallest spheres of 68Ga in image quality measurements, where clearly lower values are obtained. For 90Y, the low number of counts leads to a large variability in the image quality measurements. The primary factor for the sensitivity change is the scale factor related to the positron emission fraction. There is also an impact on the peak NECR, which is lower for 68Ga than for 18F and appears at higher activities. Conclusions: The system performance of GE Signa integrated PET/MR was substantially different, in terms of NEMA spatial resolution, image quality, and NECR for 68Ga and 90Y compared to 18F. But these differences are compensated by the PET/MR scanner technologies and reconstructions methods. [ABSTRACT FROM AUTHOR]

The article presents the case of a 69-year-old man whose brain magnetic resonance imaging (MRI) showed bilateral hyperintense FLAIR signals in the amygdala and hippocampus. Topics covered include the fluorodeoxyglucose (FDG)-positron emission tomography (PET) and chest X-ray which led to the diagnosis of limbic encephalitis (LE), and the treatment that the patient underwent.

A response by T. Van der Borght and colleagues to a letter to the editor about their article "EANM Procedure Guidelines for Brain Tumor Imaging Using Labelled Amino Acids Analogues" is presented.

An abstract of the article "PET imaging in healthy subjects and migraineurs suggests CGRP receptor antagonists do not have to act centrally to achieve clinical efficacy" by J. de Hoon, B. De Saint-Hubert and colleagues is presented.

There is growing agreement that early diagnosis of Alzheimer’s disease (AD) prior to onset of dementia is required for efficient clinical trials of neuroprotective interventions. In the past years, substantial progress has been made in that respect by refining clinical and neuropsychological assessment and quantitative evaluation of structural and functional brain imaging (mainly MRI and PET). It is also hoped that quantitative imaging will provide more efficient means to monitor disease progression than repeated neuropsychological testing. Alzheimer’s disease is likely to be a common clinical manifestation with diverse and multifactorial etiology, and it also needs to be distinguished from other dementias, such as fronto-temporal dementia (FTD), dementia with Lewy bodies (DLB), and vascular dementia (VD). Yet, currently available clinical tools do not yet allow identifying specific etiologies and distinguishing between different dementing diseases at the clinical stage of mild cognitive impairment. To address these needs, we have formed a multicentre network to compare molecular and neurotransmitter imaging in mild cognitive impairment. Within this network we are including normal controls and patients with mild cognitive impairment using harmonized longitudinal study protocols that share common neuropsychological and clinical assessment (MMSE, DemTect, CDR, Rey auditory verbal learning and complex figure, digit span, verbal fluency, trail making, IADL, Geriatric depression scale, NPI). Participating laboratories have established positron emission tomography (PET) or single photon emission computed tomography (SPECT) procedures to assess in vivo key molecular events, specifically amyloid deposition (C-11-PIB) and microglial activiation (C-11-PK11195), and assessment of neurotransmitter deficits, specifically acetylcholine esterase (C-11-MP4A, C-11-MP4P), nicotinic receptors (I-123-A85380), serotonin and benzodiazepine receptors, and dopamine transporters. Preliminary results and evidence from postmortem studies suggest that amyloid deposition and cholinergic deficits occur early in AD but not in FTD, serotonergic deficits may be present in AD and FTD, whereas a dopaminergic deficit is seen in DLB only. The ongoing studies in MCI patients should provide more information on whether early differential diagnosis is possible and could become available for testing of drugs that target specific molecular mechanisms and transmitter systems. [Copyright &y& Elsevier]