View clinical trials related to Fragile X Syndrome.
Filter by:The purpose of this study is to determine the effectiveness and tolerability of aripiprazole in the treatment of children and adolescents with FXS. We hypothesize that aripiprazole will be effective in decreasing aggression, SIB, agitation, and interfering repetitive behavior commonly observed in individuals with FXS. We also hypothesize that aripiprazole will be well tolerated.
Biosynthesis of proteins is essential for growth and continued maintenance of the entire neuron including axons, dendrites, and synaptic terminals, and it is clearly one of the important biochemical processes underlying adaptive changes in the nervous system. Studies in experimental animals with the quantitative autoradiographic L [1 (14)C]leucine method have demonstrated a number of the physiological and pathological conditions in which changes in regional rates of cerebral protein synthesis (rCPS) occur. We have recently developed the first fully quantitative method for determining rCPS with positron emission tomography (PET). The PET method was adapted from the autoradiographic L [1 (14)C]leucine method; it uses L [1 (11)C]leucine as the PET tracer, dynamic scanning, and a kinetic modeling approach for quantification. This method was validated in nonhuman primates by comparison of PET measurements with those based on established biochemical and autoradiographic techniques. The objective of the present study is to examine the degree to which changes in rCPS in human subjects can be quantified with the L [1 (11)C]leucine PET method. We propose three studies to be carried out sequentially. In Part I we will establish the L-[1-(11)C]leucine PET method in human subjects. In Part II we will measure rCPS in normal control subjects in two states: awake and under deep sedation/general anesthesia with propofol. A difference in rCPS between these two states may indicate that we can detect activity-dependent protein synthesis with the PET method. In Part III we will study subjects with fragile X syndrome. This patient group was chosen since the affected gene in fragile X syndrome codes for a protein that is thought to be a negative regulator of message translation. Thus an effect on protein synthesis may be very close to the underlying genetic abnormality in fragile X syndrome. Regionally selective increases in rCPS have been found in studies in a mouse model of this disease. The present study will establish the sensitivity of the L [1 (11)C]leucine PET method to detect changes in rCPS in human subjects. A quantitative and sensitive method to measure rCPS with PET will augment the tools available for investigating the brain and its regional adaptive responses. Ultimately the method may have widespread applications, not only for the study of normal development and plasticity but also in clinical medicine, e.g., in the investigation of disorders of brain development, recovery from brain injury, and neurodegenerative diseases. SPECIFIC AIMS 1. <TAB>Establish the L-[1-(11)C]leucine PET method for measurement of rCPS in human subjects. Evaluate the optimal scan time and the variability of the measurement in an individual. 2. <TAB>Determine the effect of deep sedation with propofol on rCPS in normal human subjects. We will use the [1-(11)C]leucine PET method to evaluate lambda, i.e., the fraction of the precursor pool for protein synthesis that is derived from arterial plasma, and rCPS in the same subjects under awake and deep sedation conditions. I)<TAB>Hypothesis 1a. Deep sedation with propofol has effects on rCPS. II)<TAB>Hypothesis 1b. Deep sedation with propofol has effects on values of lambda. 3. <TAB>Assess the sensitivity of the [1-(11)C]leucine PET method to detect differences in rCPS in subjects with fragile X syndrome. I)<TAB>Hypothesis 3a. There are regionally selective changes in rCPS in subjects with fragile X syndrome compared with age-matched healthy controls. Regions affected include hippocampus, thalamus, hypothalamus, amygdala, and frontal and parietal cortex. II)<TAB>Hypothesis 3b. In centrum semiovale, cerebellum, striatum and occipital and temporal cortex rCPS are unchanged in subjects with fragile X syndrome compared with age-matched healthy controls. III)<TAB>Hypothesis 3c. Values of lambda in the brain as a whole and in the regions examined are unchanged in subjects with fragile X syndrome compared with age-matched healthy controls. IV) Hypothesis 3d. The average rate of protein synthesis in the brain as a whole is unchanged in subjects with fragile X syndrome compared with age-matched healthy controls.
Fragile X syndrome is the most common known inherited cause of neurodevelopmental disability. Functional magnetic resonance imaging (fMRI) studies from our laboratory indicate that specific brain regions using the neurochemical, acetylcholine, show significantly reduced activation during learning. Since donepezil is a medication that enhances acetylcholine function in the brain, the purpose of this study is to determine if donepezil has any beneficial effect on behavior or cognition in subjects with fragile X syndrome.
This study will investigate whether CX516 can improve attention, memory, language, or behavior in adults with Fragile X Syndrome and/or Autism. CX516 is an AMPAKINE® compound. AMPAKINE compounds enhance synaptic strength. There is evidence to suggest that the synapses in the brain of an individual with fragile X syndrome are immature and abnormal. It is possible CX516 may partially correct this synaptic transmission defect and lead to improvement in cognitive and behavioral functioning. There is also reason to believe that these changes caused by CX516 could be helpful in managing cognitive and behavioral symptoms in patients with autistic disorder. Involvement for each participant will last 28 days. Participants will be given study medication, a physical exam, and a variety of cognitive assessment tests to study potential drug effectiveness at improving disease symptoms.