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Objective: Automated voxel-based analysis methods are used to detect cortical hypometabolism typical of Alzheimer's Disease (AD) on FDG-PET brain scans. We compared the accuracy of two clinically validated tools for their ability to identify those MCI subjects progressing to AD at followup, to evaluate the impact of the analysis method on FDG-PET diagnostic performance., Methods: SPMGrid and BRASS (Hermes Medical Solutions, Stockholm, Sweden) were tested on 131 MCI and elderly healthy controls from the EADC PET dataset. The concordance between the tools was tested by correlating the quantitative parameters (z- and t-values), calculated by the two software tools, and by measuring the topographical overlap of the abnormal regions (Dice score). Three independent expert readers blindly assigned a diagnosis based on the two map sets. We used conversion to AD dementia as the gold standard., Results: The t-map and z-map calculated with SPMGrid and BRASS, respectively, showed a good correlation (R > .50) for the majority of individual cases (128/131) and for the majority of selected regions of interest (ROIs) (98/116). The overlap of the hypometabolic patterns from the two tools was, however, poor (Dice score .36). The diagnostic performance was comparable, with BRASS showing significantly higher sensitivity (.82 versus .59) and SPMGrid showing higher specificity (.87 versus .52)., Conclusion: Despite similar diagnostic performance in predicting conversion to AD in MCI subjects, the two tools showed significant differences, and the maps provided by the tools showed limited overlap. These results underline the urgency for standardization across FDG-PET analysis methods for their use in clinical practice., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: To understand the substrates of response and nonresponse and to identify potential biomarkers for the selection and follow-up of patients with essential tremor (ET) treated with Gamma Knife (Elekta AB, Stockholm, Sweden) of the ventral intermediate nucleus (GKVIM)., Objective: To characterize positron emission tomography (PET) changes in the metabolism of glucose and metabolic connectivity in patients with ET treated by GKVIM through observational study., Methods: Forty-two patients with right ET were referred to 18F-fluorodesoxyglucose positron emission tomography (18F-FDG PET) imaging before and after left GKVIM. Statistical Parametric Mapping T-score map comparisons were performed between pre- and post-GKVIM groups and between clinical responders and nonresponders. Metabolic connectivity was evaluated by the interregional correlation analysis method., Results: After GKVIM, patients with ET exhibited decreased left thalamic metabolism, which was associated with remote metabolic decreases in the right cerebellum, left temporal gyri, and bilateral frontal gyri (P < .05, family-wise error-corrected). Additionally, nonresponders (n = 7) showed metabolic decreases in the right temporo-occipital area (P < .005 corrected for cluster volume) after GKVIM. The metabolism in this area was already reduced in nonresponders before treatment in comparison to that in responders and was predictive of future response (sensitivity: 89%; specificity: 71%). In nonresponder patients, strong connectivity between the left thalamus and right temporo-occipital area was found before GKVIM and was lost after treatment, whereas this connectivity remained weak and stable in responders., Conclusion: These findings could lead to better knowledge of the variability in the metabolic PET profiles among patients with ET, particularly the integration of 18F-FDG PET imaging in the pretherapeutic evaluation of patients with refractory ET candidates for GKVIM., (Copyright © 2018 by the Congress of Neurological Surgeons.)

Swedish snus is a smokeless tobacco product that contains reduced levels of harmful compounds compared with cigarette smoke. In Sweden, where snus use exceeds smoking among men, relatively low rates of major smoking-related diseases have been recorded. To better understand how snus use could align with current tobacco harm reduction strategies, its potential mechanisms of toxicity must be investigated. This study aimed to determine, via a systems toxicology approach, the biological impact of repeated 72-hour exposure of human gingival epithelial organotypic cultures to extracts from both a commercial and a reference snus and the total particulate matter (TPM) from cigarette smoke. At concentrations relevant for human use, cultures treated with snus extracts induced mild, generally reversible biological changes, while TPM treatment induced substantial morphological and inflammatory alterations. Network enrichment analysis and integrative analysis of the global mRNA and miRNA expression profiles indicated a limited and mostly transient impact of the snus extracts, in particular on xenobiotic metabolism, while the effects of TPM were marked and sustained over time. High-confidence miRNAs that might be related to pathological conditions in vivo were identified. This study highlights the limited biological impact of Swedish snus extract on human organotypic gingival cultures., (Copyright © 2018. Published by Elsevier Ltd.)

Background: Hypophysectomy performed by craniotomy or percutaneous techniques leads to complete pain relief in more than 70% to 80% of cases for opioid refractory cancer pain. Radiosurgery could be an interesting alternative approach to reduce complications., Objective: To assess the analgesic efficacy compared with standard of care is the primary goal. The secondary objectives are to assess ophthalmic and endocrine tolerance, drug consumption, quality of life, and mechanisms of analgesic action., Methods: The trial is multicenter, randomized, prospective, and open-label with 2 parallel groups. This concerns patients in palliative care suffering from nociceptive or mixed cancer pain, refractory to standard opioid therapy. Participants will be randomly assigned to the control group receiving standards of care for pain according to recommendations, or to the experimental group receiving a pituitary GammaKnife (Elekta, Stockholm, Sweden) radiosurgery (160 Gy delivered in pituitary gland) associated with standards of care. Evaluation assessments will be taken at baseline, day0, day4, day7, day14, day28, day45, month3, and month6., Expected Outcomes: We could expect pain improvement in 70% to 90% of cases at day4. In addition we will assess the safety of pituitary radiosurgery in a vulnerable population. The secondary endpoints could show decay of opioid consumption, good patient satisfaction, and improvement of the quality of life., Discussion: The design of this study is potentially the most appropriate to demonstrate the efficacy and safety of radiosurgery for this new indication. New recommendations could be obtained in order to improve pain relief and quality of life.