There are about 13332 clinical studies being (or have been) conducted in Netherlands. The country of the clinical trial is determined by the location of where the clinical research is being studied. Most studies are often held in multiple locations & countries.
This study aims to investigate the role of fronto-striatal circuits and cognitive control in the perseverative and inflexible behavior that is a defining feature of autism. We hypothesize that deficits in the development of fronto-striatal circuitry may underlie cognitive inflexibility in autism. Specifically, we hypothesize that repetitive, inflexible behavior arises as (1) fronto-striatal systems are capable of learning patterns present in the environment (as in implicit learning paradigms), but are unable to adapt behavior to changing circumstances, related to either (2) decreased ability of basal ganglia to detect violations of expectancy, (3) decreased ability of prefrontal cortex to respond to detected violations, or (4) decreased connectivity of the circuits. We are conducting three functional Magnetic Resonance Imaging (fMRI) studies to address these hypotheses.
Growth retardation in utero may be caused by uteroplacental vascular insufficiency. When Doppler ultrasound studies of the umbilical artery are abnormal pathological intrauterine growth restriction (IUGR) can be diagnosed. IUGR fetuses have a higher mortality and morbidity, both perinatally and on the longer term. This is probably due to chronic malnourishment and hypoxia due to placental insufficiency. This placental dysfunction causes generation of harmful free oxygen radicals in the fetus. The IUGR fetus has a diminished antioxidative capacity which means these free radicals cannot be buffered sufficiently. This leads to fetal oxidative stress. Previous studies have shown that allopurinol can inhibit the cascades that lead to generation of free radicals. High dosed allopurinol also scavenges radicals and binds free iron without adverse effects on the fetus or mother. As IUGR is associated with placental insufficiency and excessive production of free radicals we hypothesize that antenatal allopurinol administration could lead to a decrease in oxidative stress in the mother and fetus and subsequent improvement of the maternal and/or neonatal outcome.