Use of brain imaging (computed tomography and magnetic resonance imaging) in first-episode psychosis: review and retrospective study.

OBJECTIVE: To identify and review available evidence on the diagnostic yield of brain computed tomographies (CTs) and magnetic resonance images (MRIs) in first-episode psychosis, and examine yield in our own institution (Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, Quebec). METHOD: Using MEDLINE (1966 to October 2007) and EMBASE (1980 to October 2007), we identified and analyzed studies that examined imaging yields in first-episode psychosis; yield being defined as the percentage of scans showing abnormalities that may result in psychosis. We also retrospectively analyzed diagnostic yields in 46 patients hospitalized in our institution between 2001 and 2006 for first-episode psychosis. RESULTS: Five studies were deemed relevant. Including our own series, the sample comprised 384 CT and 184 MRI scans. Point estimate for diagnostic yield was 1.3% for CT and 1.1% for MRI scans. These yields likely overestimate clinical usefulness of findings. MRI scans also resulted in a sizeable number of fortuitous, clinically irrelevant findings. CONCLUSIONS: In first-episode psychosis, routine CT or MRI scans are of little benefit and should be reserved for situations where history or examination suggests neurological causation, or possibly for people aged 50 years and older.

1T Pixel Using Floating-Body MOSFET for CMOS Image Sensors.

We present a single-transistor pixel for CMOS image sensors (CIS). It is a floating-body MOSFET structure, which is used as photo-sensing device and source-follower transistor, and can be controlled to store and evacuate charges. Our investigation into this 1T pixel structure includes modeling to obtain analytical description of conversion gain. Model validation has been done by comparing theoretical predictions and experimental results. On the other hand, the 1T pixel structure has been implemented in different configurations, including rectangular-gate and ring-gate designs, and variations of oxidation parameters for the fabrication process. The pixel characteristics are presented and discussed.

Food effect on the bioavailability of two distinct formulations of megestrol acetate oral suspension.

OBJECTIVE: Megestrol acetate oral suspension (MAOS) is an appetite stimulant indicated for cachexia in patients with AIDS. It is available in its original formulation, Megace (MAOS), and as a nanocrystal dispersion, Megace ES (MA-ES). Three studies were conducted to evaluate the pharmacokinetic properties of these formulations under fed and fasting conditions. METHODS: An open-label, crossover trial was conducted in 24 healthy males randomized to MA-ES 625 mg/5 mL given with a high-calorie, high-fat meal, or after an overnight fast. Blood samples were drawn at multiple time points and pharmacokinetic parameters were determined. Two separate, open-label reference studies evaluated MAOS 800 mg/20 mL in 40 fed or 40 fasting healthy male volunteers. RESULTS: In fasting MA-ES subjects, the average maximum concentration (C(max)) was 30% less than the fed C(max) value. For MAOS, fasting C(max) was 86% less than fed C(max). In fasting subjects, the area under the curve was 12,095 ng.h/mL for MA-ES, and 8,942 ng.h/mL for MAOS. In fed subjects, the absorption of the two formulations was comparable. CONCLUSION: Bioavailability and absorption are greater for MA-ES than MAOS in fasting subjects. MA-ES may be a preferred formulation of megestrol acetate when managing cachectic patients whose caloric intake is reduced.