Neurodegeneration

The objective of this protocol is to use a case-control paradigm to compare the response to an intravenous administration of kisspeptin in individuals with and without post-covid-19 syndrome. The study subjects will receive a single bolus of kisspeptin.

The objective of this protocol is to use a case-control paradigm to compare the response to an intravenous administration of kisspeptin in individuals with and without post-covid-19 syndrome. The study subjects will receive a single bolus of kisspeptin. This study will utilize the technique of frequent blood sampling (q10 minutes) to provide detailed neuroendocrine characterization of endogenous LH secretion before and after kisspeptin administration. This frequency of blood sampling is required to define the features of LH pulses.

In addition to neuronal loss, dysfunction in brain network connectivity has been identified as a correlate of cognitive deficits in neurodegenerative and post-traumatic brain injury states. Transcranial alternating current stimulation (tACS) has been suggested as a promising, non-invasive, method of normalizing network connectivity and hence improving cognition, notably memory. This study will examine the efficacy of tACS at improving working memory performance in patients with neurodegeneration and its correlation to changes in network connectivity, based on functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) imaging data.

Veterans with mid to later stage Parkinson's disease (PD) may not be able to work out as hard as they need to, to prevent brain cell loss. Maybe they could work out longer and more frequently to make up for this during their good times and good weeks and then rest during the bad weeks. The investigators will compare how effective working out a lot one week per month with a break of three weeks is to continuously exercising weekly with no breaks in people with mid stage PD. The investigators will look at how fast participants walk per minute, whether they become more physically active, the biochemicals in their blood, and at how stiff their blood vessels are before and after the exercise.

This study aims to investigate how moderate wine consumption influences circulating extracellular vesicles (EVs) in healthy adults. EVs are small particles released by cells that carry proteins, lipids, and genetic material, and play important roles in communication between cells. Participants will consume a single serving of red or white wine, and blood samples will be collected before and after consumption to study changes in the composition and function of EVs. The study will also assess how these EVs affect vascular, immune, and brain-related cells. The results are expected to improve our understanding of how moderate wine intake contributes to cardiovascular and brain health.

In this study, the investigators aim to provide a deeper understanding of Parkinson's disease and find a biomarker of Parkinson's disease. This is done using imaging scans called Positron Emission tomography (PET), Single Photon Emission Computed Tomography (SPECT), and Magnetic Resonance Imaging (MRI). The findings will provide a deeper understanding of the brain changes in Parkinson's disease. More importantly, this study will help with the discovery and development of new medications aiming to delay progression of Parkinson's disease symptoms

In this study, the researchers aim to find a biomarker of PD. Using imaging scans called Positron Emission tomography (PET), Single Photon Emission Computed Tomography (SPECT), and Magnetic Resonance Imaging (MRI). The PET and SPECT scans use small amounts of radiation and specific compounds called tracers, to study chemical changes in the brain in a way not possible with any other procedure. The MRI uses magnetic fields to generate images of brain structure and function

To evaluate the potential usefulness of 18F-S16/T807 positron emission tomography/computed tomography (PET/CT) for the diagnosis of primary and metastatic lesions in various Tau-related disease patients.

This is a multi-center longitudinal study that consists of five cohorts: cognitive normal aging (CN), Subjective cognitive impairment (SCI), mild cognitive impairment (MCI), Alzheimer's disease (AD) and vascular cognitive impairment (VCI). The goals of this study are as follow: 1.To establish longitudinal cohort study database containing comprehensive epidemiological data, neuropsychological test data, laboratory parameters, image data and biological samples. 2. To determine the risk factors of AD and other dementias. 3. To explore the conversion rates from CN to SCI, MCI or AD and the risk factors as well as biomarkers for the progression from CN to SCI, MCI or AD. 4. To explore and validate blood, CSF, urine, imaging and other biomarkers for the early detection and progression of AD.