Hypocretin/orexin selectively increases dopamine efflux within the prefrontal cortex: involvement of the ventral tegmental area.

Hypocretins (HCRTs) modulate a variety of behavioral and physiological processes, in part via interactions with multiple ascending modulatory systems. Further, HCRT efferents from the lateral hypothalamus innervate midbrain dopamine (DA) nuclei, and DA cell bodies express HCRT receptors. Combined, these observations suggest that HCRT may influence behavioral state and/or state-dependent processes via modulation of DA neurotransmission. The current studies used in vivo microdialysis in the unanesthetized rat to first characterize the effect of intracerebroventricular infusion of HCRT-1 (0.07, 0.7 nmol) on extracellular levels of DA within the prefrontal cortex (PFC) and nucleus accumbens (Acc). Electroencephalographic/electromyographic measures of sleep-wake state were collected along with select behavioral measures (eg locomotor activity, grooming). HCRT-1 dose-dependently increased PFC dialysate DA levels, and these increases were closely correlated with increases in time spent awake. In contrast, Acc DA levels were unaffected. Additional studies examined whether HCRT-1 acts directly within the ventral tegmental area (VTA) to selectively increase PFC DA efflux and modulate behavioral state. Unilateral infusion of HCRT-1 (0.1, 1.0 nmol) within the VTA increased PFC, but not Acc, DA levels. Importantly, intra-VTA infusion of HCRT-1 increased the time spent awake and grooming. Moreover, HCRT-induced increases in both time spent awake and time spent grooming were significantly correlated with post-infusion PFC DA levels. The current observations predict a prominent modulatory influence of HCRT on PFC-dependent cognitive and affective processes that results, in part, from actions within the VTA. Additionally, these observations suggest that the activation of VTA DA neurons contributes to the behavioral state-modulatory actions of HCRT.     

Contribution of hypoxia-measuring molecular imaging techniques to radiotherapy planning and treatment

Hypoxia is related to poor prognosis because it is associated to chemo-and radioresistance. During recent years the evolution of imaging methods like PET/CT and MRI has meant the appearance of new perspectives with direct implications in radiation therapy. We discuss previous experiences in staging, planning and in the follow-up process with these techniques for measuring tumour hypoxia.     

Sensory functions of institutionalized Romanian infants: A pilot study

Infants living in an orphanage (n = 22) in Romania were assessed on the Test of Sensory Functions in Infants (TSFI). Testing of the institutionalized infants was done before and 6 months after an enriched caregiver intervention program. Results showed significant changes in areas of reactivity to tactile deep pressure, visual-tactile integration, oculomotor control, reactivity to vestibular stimulation and total test responses. No significant changes occurred in the area of adaptive motor functions. Effects of sensory deprivation resulting from institutional settings and changes that can occur from enriched caregiver environments are discussed.     

Saline infusion sonohysterography: technique, indications, and imaging findings.

OBJECTIVE: To review the technique, indications, and common imaging findings regarding saline infusion sonohysterography. METHODS: The literature on saline infusion sonohysterography was reviewed. Pertinent images from our institution are presented to illustrate common imaging findings. RESULTS: From the literature review, we summarize the various clinical scenarios in which saline infusion sonohysterography is useful and give examples from our clinical practice. CONCLUSIONS: Saline infusion sonohysterography is a useful procedure for evaluation of endometrial and subendometrial abnormalities.