Clinical Research Directory

Effects of tDCS for Enhancing Cognitive Function in Individuals With Persistent Post-Concussion Syndrome

Globally, 10 million new traumatic brain injury (TBI) cases are estimated annually, with mild traumatic brain injury (mTBI) accounting for 75-90% of all TBI cases. It is estimated that 40-80% of individuals with mTBI may experience the post-concussion syndrome (PCS), which is characterized by a range of physical, cognitive, and emotional symptoms. Although the underlying basis of cognitive dysfunction of patients with persistent PCS remains to be clarified, converging evidence shows that the clinical symptoms is underpinned by abnormal neural information processing as a result of axonal injury due to mTBI. Recent studies have demonstrated abnormalities in both structural and functional cortical connectivity, and a loss of cortical excitability-inhibitory (E/I) balance after TBI. Yet, there is no consensus for treating chronic symptoms of concussion, and PCS remains a chronic and highly disabling condition. One potential treatment option is transcranial direct current stimulation (tDCS), a non-invasive brain stimulation technique that has been shown to modify behavior by enhancing connectivity between targeted brain areas. However, research on the therapeutic effect of tDCS on PCS symptoms is limited, and the neurologic mechanisms underlying its effects are not well understood. The proposed study aims to address these knowledge gaps by examining the effects of tDCS on the central nervous system function in patients with PCS, with a specific focus on functional cortical connectivity and cognitive functions such as processing speed and executive function. The study also aims to add value to existing evidence by potentially opening new directions for designing intervention programs for the treatment of PCS after mTBI.

Non-Invasive Monitoring Of Metabolite Levels Using Novel And Adapted MR Spectroscopy Techniques

This Swiss National Science Foundation (SNF) funded project and the linked European project aim * to improve magnetic resonance (MR) methods, specifically MR spectroscopy and metabolic imaging (making them more sensitive and accurate - also less dependent on motion), * to extend them (making previously unobservable metabolites visible) and also * to make them more stable (suitable for routine clinical use). Magnetic resonance spectroscopy (MRS) is closely related to the widely used magnetic resonance imaging (MRI). Both methods are based on the same physical effect and are performed on the same equipment. However, while MRI mainly images the anatomy inside the body, MRS gives us information about the metabolism of the tissue. The main goal of this study is to develop and improve methods of MRS to better measure the concentrations of endogenous substances without actual intervention. MRS methodology development is performed in 4 steps: 1. A new method is developed and optimized theoretically and in sample preparations (solutions of chemicals). 2. The new methodology is evaluated in single healthy volunteers and optimized step by step for the conditions of use in the human body. 3. The methodology in evaluated in small groups of healthy volunteers (measurement accuracy and range of variation in healthy volunteers). 4. Feasibility is studied in different situations with possibly different metabolic situations (e.g. awake versus asleep or before and after muscular exertion). For this purpose, about 100 subjects will be measured for different subprojects. Thus, among other things, one determines the measurement accuracy and also normal values in healthy subjects for the assessment of diseases in future studies.

Magnetic Resonance & Optical Spectroscopy Validation

The purpose of this study is to develop and refine techniques for using magnetic resonance and optical spectroscopy to investigate how your body uses energy.

New Imaging Biomarkers Predictive of MA Progression

The pathophysiology of AD is complex. In addition to amyloid plaques and neurofibrillary degeneration, there is a metabolic alteration of the energy pathways, oxidative phosphorylation and glycolysis, which are involved in brain function. Several authors have shown a series of early metabolic dysregulations via an increase in phosphorylation at the origin of neuronal death. Ultra-high field imaging (7T MRI) may allow, with its better spatial resolution and advanced imaging techniques, to shed light on the mechanisms of progression of Alzheimer's disease. A Magnetic Resonance Spectroscopy (MRS) examination can be coupled to brain MRI without additional risk for the patient. Multinuclear 1H-31P metabolic imaging is a promising tool that can provide information on the metabolic evolutionary profile of AD. Thus, we propose a longitudinal study in patients with early-stage AD on 7T MRI-MRS.

Investigating Myosteatosis in Steatotic Liver Diseases

Steatotic liver diseases (SLD) are the most common chronic liver diseases worldwide. SLD are defined by an excessive liver lipid content (steatosis) of more than 5% of the total liver weight and includes 3 clinical entities : metabolic dysfunction-associated steatotic liver disease (MASLD), alcohol-related liver disease (ALD) and a mixed entity combining the two settings referred as MetALD. SLD are associated to extra-hepatic complications such as cardiovascular diseases, insulin resistance or muscle changes. Among the latter, myosteatosis, defined by an excessive muscle fat content, has been reported as a muscle change in MASLD occuring even in non-cirrhotic stages. Investigators will explore these muscle changes in SLD patients according to the severity of the underneath liver disease.

MRI Biomarkers Predictive of Disability Progression in Patients With Multiple Sclerosis

The transition from relapsing-remitting multiple sclerosis to secondarily progressive multiple sclerosis (SPMS) is difficult to identify. Typically, SPMS is diagnosed retrospectively, with a significant delay, on the basis of a clinical history of progressive worsening, independent of relapses. Thus, SPMS is often associated with a considerable period of diagnostic uncertainty. The use of ultra-high field imaging can shed light on the mechanisms of disability progression thanks to its better spatial resolution and advanced imaging techniques. The new morphological imaging techniques make it possible to visualize chronic inflammatory lesions and to evaluate their evolution. It also allows for the precise measurement of brain atrophy, a reference in the evaluation of neurodegeneration. Metabolic imaging via proton spectroscopy allows the analysis of several promising cerebral metabolites that can provide information on cellular energy metabolism, mitochondrial function, or oxidative stress, and can help identify tissues at risk of neurodegeneration. Sodium imaging can provide information on axonal energy metabolism before the occurrence of stable and irreversible axonal damage. This technique is promising as an early marker of neurodegeneration.