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Post-label delay times of ≥4 seconds are needed and may be combined with multidelay strategies for robust ASL assessment of CBF in Moyamoya disease.

Abstractβ-secretase (BACE1), an enzyme responsible for the production of amyloid β-peptide (Aβ), is increased by oxidative stress and is elevated in the brains of patients with sporadic Alzheimer's disease (AD). Here we show that oxidative stress fails to induce BACE1 expression in presenilin-1 (γ-secretase)-deficient cells and in normal cells treated with γ-secretase inhibitors. Oxidative stress-induced β-secretase activity and sAPPβ levels were suppressed by γ-secretase inhibitors. Levels of γ-and β-secretase activities were greater in brain tissue samples from AD patients compared to non-demented control subjects, and the elevated BACE1 level in the brains of 3xTgAD mice was reduced by treatment with a γ-secretase inhibitor. Our findings suggest that γ-secretase mediates oxidative stress-induced expression of BACE1 resulting in excessive Aβ production in AD. The authors declare that they have no actual or potential conflicts of interest to disclose. Appropriate approval and procedures were used concerning human subjects and animals.

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A reliable and automated radiosynthesis for providing routine clinical-grade [F]FTC-146 for human studies was established in a modified GE TRACERlab FX. PET/MRI demonstrated the initial tracer biodistribution in humans, and clinical studies investigating different S1R-related diseases are in progress.

Cancer cells reprogram their metabolism to meet increased biosynthetic demands, commensurate with elevated rates of replication. Pyruvate kinase M2 (PKM2) catalyzes the final and rate-limiting step in tumor glycolysis, controlling the balance between energy production and the synthesis of 2

No abstract

Major depressive disorder (MDD) is characterized by the altered integration of reward histories and reduced responding of the striatum. We have posited that this reduced striatal activation in MDD is due to tonically decreased stimulation of striatal dopamine synapses which results in decremented propagation of information along the cortico-striatal-pallido-thalamic (CSPT) spiral. In the present investigation, we tested predictions of this formulation by conducting concurrent functional magnetic resonance imaging (fMRI) and 11C-raclopride positron emission tomography (PET) in depressed and control (CTL) participants. We scanned 16 depressed and 14 CTL participants with simultaneous fMRI and 11C-raclopride PET. We estimated raclopride binding potential (BPND), voxel-wise, and compared MDD and CTL samples with respect to BPND in the striatum. Using striatal regions that showed significant between-group BPND differences as seeds, we conducted whole-brain functional connectivity analysis using the fMRI data and identified brain regions in each group in which connectivity with striatal seed regions scaled linearly with BPND from these regions. We observed increased BPND in the ventral striatum, bilaterally, and in the right dorsal striatum in the depressed participants. Further, we found that as BPND increased in both the left ventral striatum and right dorsal striatum in MDD, connectivity with the cortical targets of these regions (default-mode network and salience network, respectively) decreased. Deficits in stimulation of striatal dopamine receptors in MDD could account in part for the failure of transfer of information up the CSPT circuit in the pathophysiology of this disorder.