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Purpose: Scintigraphic imaging of malignant glioblastoma (MG) continues to be challenging. We hypothesized that VPAC1 cell surface receptors can be targeted for positron emission tomography (PET) imaging of orthotopically implanted MG in a mouse model, using a VPAC1-specific peptide [ 64 Cu]TP3805., Procedures: The expression of VPAC1 in mouse GL261 and human U87 glioma cell lines was determined by western blot. The ability of [ 64 Cu]TP3805 to bind to GL261 and U87 cells was studied by cell-binding. Receptor-blocking studies were performed to validate receptor specificity. GL261 tumors were implanted orthotopically in syngeneic T-bet knockout C57BL/6 mouse brain (N = 15) and allowed to grow for 2-3 weeks. Mice were injected i.v., first with ~ 150 μCi of 2-deoxy-2-[ 18 F]fluoro-D-glucose ([ 18 F]FDG) then 24 h later with ~ 200 μCi of [ 64 Cu]TP3805. In another set of tumor-bearing mice, (N = 5), ionic [ 64 Cu]Cl 2 was injected as a control. Mice were imaged at a 2-h post-injection using an Inveon micro-PET/CT, sacrificed and % ID/g of [ 64 Cu]TP3805 and [ 64 Cu]Cl 2 were calculated in a tumor, normal brain, and other tissues. For histologic tissue examination, 3-μm thick sections of the tumors and normal brain were prepared, digital autoradiography (DAR) was performed, and then the sections were H&E stained for histologic examination., Results: Western blots showed a strong signal for VPAC1 on both cell lines. [ 64 Cu]TP3805 cell-binding was 87 ± 1.5 %. Receptor-blocking reduced cell-binding to 24.3 ± 1.5 % (P < 0.01). PET imaging revealed remarkable accumulation of [ 64 Cu]TP3805 in GL261 MG with a negligible background in the normal brain, as compared to [ 18 F]FDG. Micro-PET/CT image analyses and tissue distribution showed that the brain tumor uptake for [ 64 Cu]TP3805 was 8.2 ± 1.7 % ID/g and for [ 64 Cu]Cl 2 2.1 ± 0.5 % ID/g as compared to 1.0 ± 0.3 % ID/g and 1.4 ± 0.3 % ID/g for normal mouse brains, respectively. The high tumor/normal brain ratio for [ 64 Cu]TP3805 (8.1 ± 1.1) allowed tumors to be visualized unequivocally. Histology and [ 64 Cu]TP3805 DAR differentiated malignant tumors from healthy brain and confirmed PET findings., Conclusion: Targeting VPAC1 receptors using [ 64 Cu]TP3805 for PET imaging of MG is a promising novel approach and calls for further investigation.

Introduction: Combined infections from Candida albicans and Staphylococcus aureus are a leading cause of death in the developed world. Evidence suggests that Candida enhances the virulence of Staphylococcus -hyphae penetrate through tissue barriers, while S. aureus tightly associates with the hyphae to obtain entry to the host organism. Indeed, in a biofilm state, C. albicans enhances the antimicrobial resistance characteristics of S. aureus . The association of these microorganisms is also associated with significantly increased morbidity and mortality. Due to this tight association we hypothesised that metabolic effects were also in evidence., Objectives: To explore the interaction, we used a novel GC-Orbitrap-based mass spectrometer, the Q Exactive GC, which combines the high peak capacity and chromatographic resolution of gas chromatography with the sub-ppm mass accuracy of an Orbitrap system. This allows the capability to leverage the widely available electron ionisation libraries for untargeted applications, along with expanding accurate mass libraries and targeted matches based around authentic standards., Methods: Optimised C. albicans and S. aureus mono- and co-cultured biofilms were analysed using the new instrument in addition to the fresh and spent bacterial growth media., Results: The targeted analysis experiment was based around 36 sugars and sugar phosphates, 22 amino acids and five organic acids. Untargeted analysis resulted in the detection of 465 features from fresh and spent medium and 405 from biofilm samples. Three significantly changing compounds that matched to high scoring library fragment patterns were chosen for validation., Conclusion: Evaluation of the results demonstrates that the Q Exactive GC is suitable for metabolomics analysis using a targeted/untargeted methodology. Many of the results were as expected: e.g. rapid consumption of glucose and fructose from the medium regardless of the cell type. Modulation of sugar-phosphate levels also suggest that the pentose phosphate pathway could be enhanced in the cells from co-cultured biofilms. Untargeted metabolomics results suggested significant production of cell-wall biosynthesis components and the consumption of non-proteinaceous amino-acids., Competing Interests: Compliance with ethical standards Conflicts of Interest Paul Silcock (PS) and Cristian Cojocariu (CC) are employed by Thermo Fisher Scientific. Thermo Fisher provided technical support, loan of instrumentation and consumables to the project. Research Involving Human Participants and/or Animals No studies contained in this article involved human participants or animals. Informed consents were not required for this study.

Viral insults that occur during early postnatal periods, can affect neuronal systems which exhibit significant postnatal development, such as the cerebral cortex and cerebellum. Borna disease virus (BDV) is a single-strand RNA virus which replicates in the nervous system of many species after experimental inoculation and causes acute neurological disease. Neonatal rats infected with BDV do not mount an aggressive response to the virus like their adult counterparts, but instead develop a persistent BDV infection with less overt clinical sequelae. Recently, the cerebellum, a neural structure associated with regulation of motor behavior, and perhaps with higher cognitive functions, has been demonstrated to be a target of neonatal BDV infections in rats (Bautista et al, 1995). In the present study neonatal rats were infected with BDV and their cerebella were analyzed histologically and immunohistochemically at 7 months of age. The cerebella of infected animals were reduced in size but normal foliation and laminar organization was present. However, as visualized with immunohistochemistry for the Purkinje cell-specific antigen calbindin, there were numerous gaps within the Purkinje cell layer and in the molecular layer which contains the Purkinje cell dendritic trees. We estimated the number of Purkinje cells and found there was an approximately 75% loss of PC in adult rats neonatally infected with BDV. These results suggest that neonatal BDV infection may either (1) target the PC and cause the death of these cells directly or (2) acts indirectly by triggering an immune response which is then responsible for the loss of these cells.

The presence of antibodies reactive with Borna disease virus (BDV) in the sera of some patients with certain psychiatric illnesses has been taken as evidence that this veterinary neurotrophic virus may occasionally infect and cause psychiatric disorders in humans. In this paper, we report the results of our studies concerning the detection of BDV-specific RNA in blood cells from patients with psychiatric diseases. Contrary to the results obtained by others, we have found no evidence for the presence of BDV-RNA in such cells. Prior work with BDV sequences in the assay environment, together with the exquisite sensitivity of RT-PCR, may account for the sporadic appearance of false positive evidence that BDV-specific RNA is present in human blood cells.