OBJECTIVES To describe a new first-trimester sonographic landmark, posterior displacement of the midbrain and aqueduct of Sylvius, which may be useful in early screening for neural tube defects. METHODS This was a prospective study of 457 normal fetuses at 11 + 0 to 13 + 6 weeks' gestation. We measured the distance from the posterior border of the aqueduct of Sylvius to the anterior border of...

Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on local circulation and apoptosis in the midbrain were investigated in zebrafish (Danio rerio) embryos during early development. Embryos were exposed to TCDD from 24 h post fertilization (hpf) until observation, in water maintained at 28.5 degrees C. TCDD decreased blood flow in the mesencephalic vein, the only vessel perfusing the dorsal m...

Anti-apoptotic proteins are suggested to be important for the normal health of neurons and synapses as well as for resilience to stress. In order to determine whether stressful events may influence the expression of anti-apoptotic protein Bcl-xL in the midbrain and specifically in the midbrain serotonergic (5-HT) neurons involved in neurobehavioral responses to adverse stimuli, adult male rats ...

Chick midbrain comprises two major components along the dorsoventral axis, the tectum and the tegmentum. The alar plate differentiates into the optic tectum, while the basal plate gives rise to the tegmentum. It is largely unknown how the differences between these two structures are molecularly controlled during the midbrain development. The secreted protein Sonic hedgehog (Shh) produced in the...

Although spinal commissural neurons serve as a model system for studying the mechanisms that underlie axonal pathfinding during development, little is known about their synaptic targets. Previously we identified a group of ventromedially located commissural neurons in rat spinal cord that are gamma-aminobutyric acid (GABA)-ergic and express L1 CAM on their axons. In this study, serial sagittal ...

Hostile jokes (HJs) provide aggressive catharsis and a feeling of superiority. Behavioral research has found that HJs are perceived as funnier than non-hostile jokes (NJs). The purpose of the present study was to identify the neural correlates of the interaction between type and humor by comparing HJs, NJs, and their corresponding hostile sentences (HSs) and non-hostile sentences (NSs). HJs pri...

Development of midbrain dopaminergic neurons is known to depend on inductive signals derived from the ventral midline, including Sonic hedgehog (Shh) as one of the identified molecules. Here we show that in addition to Shh, transforming growth factor (TGF)-beta is required for both induction and survival of ventrally located midbrain dopaminergic neurons. Like Shh, TGF-beta is expressed in earl...