The Globe reported Sunday that Boston Mayor Martin J. Walsh wouldn’t say whether he had been a grand jury witness in a federal investigation into the tactics of Boston Building Trades unions. Since then, many have chided him for not being more forthright. But that misses a critical point: Grand jury proceedings are supposed to be secret. Government agents are bound by strict confidentiality rules. They may not disclose who has been called, when they testified, or what the subject was; they are barred from releasing information about wiretaps or other evidence they have assembled. While witnesses may speak about their testimony, they do receive a letter from the government with their subpoena that strongly urges them not to do so to protect the integrity of the grand jury investigative process. And that “suggestion” is particularly important in this probe and one that Walsh was right to heed. Continue reading »
Calcitonin Gene-Related Peptide Modulates Heat Nociception in the Human Brain – An fMRI Study in Healthy Volunteers
By Mohammad Sohail Asghar, Lino Becerra, Henrik B. W. Larsson, David Borsook, and Messoud Ashina | PLoS ONE | March 18, 2016
Intravenous infusion of calcitonin-gene-related-peptide (CGRP) provokes headache and migraine in humans. Mechanisms underlying CGRP-induced headache are not fully clarified and it is unknown to what extent CGRP modulates nociceptive processing in the brain. To elucidate this we recorded blood-oxygenation-level-dependent (BOLD) signals in the brain by functional MRI after infusion of CGRP in a double-blind placebo-controlled crossover study of 27 healthy volunteers. BOLD-signals were recorded in response to noxious heat stimuli in the V1-area of the trigeminal nerve. In addition, we measured BOLD-signals after injection of sumatriptan (5-HT1B/1D antagonist).
Brain activation to noxious heat stimuli following CGRP infusion compared to baseline resulted in increased BOLD-signal in insula and brainstem, and decreased BOLD-signal in the caudate nuclei, thalamus and cingulate cortex. Sumatriptan injection reversed these changes.
The changes in BOLD-signals in the brain after CGRP infusion suggests that systemic CGRP modulates nociceptive transmission in the trigeminal pain pathways in response to noxious heat stimuli.