The glymphatics system describes a CSF-mediated clearance pathway for the removal of potentially harmful molecules, such as amyloid beta, from the brain. As such, its components may represent new therapeutic targets to alleviate aberrant protein accumulation that defines the most prevalent neurodegenerative conditions. Currently, however, the absence of any non-invasive measurement technique prohibits detailed understanding of glymphatic function in the human brain and in turn, it’s role in pathology. Here, we present the first non-invasive technique for the assessment of glymphatic inflow by using an ultra-long echo time, low b-value, multi-direction diffusion weighted MRI sequence to assess perivascular fluid movement (which represents a critical component of the glymphatic pathway) in the rat brain. This novel, quantitative and non-invasive approach may represent a valuable biomarker of CSF-mediated brain clearance, working towards the clinical need for reliable and early diagnostic indicators of neurodegenerative conditions such as Alzheimer’s disease.

The blood–cerebrospinal fluid barrier (BCSFB) is a highly dynamic transport interface that serves brain homeostasis. To date, however, understanding of its role in brain development and pathology has been hindered by the absence of a non-invasive technique for functional assessment. Here we describe a method for non-invasive measurement of BSCFB function by using tracer-free MRI to quantify rates of water delivery from arterial blood to ventricular cerebrospinal fluid. Using this method, we record a 36% decrease in BCSFB function in aged mice, compared to a 13% decrease in parenchymal blood flow, itself a leading candidate biomarker of early neurodegenerative processes. We then apply the method to explore the relationship between BCSFB function and ventricular morphology. Finally, we provide proof of application to the human brain. Our findings position the BCSFB as a promising new diagnostic and therapeutic target, the function of which can now be safely quantified using non-invasive MRI.

The blood-brain barrier (BBB) is a dynamic and regulatory interface that protects the brain parenchyma from deleterious infiltration. 1 Its composition includes endothelial cells, tight junction proteins, pericytes, and aquaporin-4 (AQP4) water channels that reside on astrocytic end feet. Dysfunction of the BBB is an early occurring

The COVID-19 crisis focused attention on how experts from different scientific fields provided advice to governments through expert committees and task forces. We compared experiences in two federal democracies, Belgium and Australia, by applying a mixed methods approach (literature review, media review, policy documents analysis). This comparative study found that expertise was institutionalized in different ways and its processes and priorities shifted over time. The policy coordination challenges inherent in federalism were largely overcome in Australia through strongly embedded health advisory processes. In Belgium, the advisory process was less stable, with advisory councils being abandoned, replaced, expanded, or downgraded during the course of the crisis.

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