Non-viral Smad7 gene delivery and attenuation of postoperative peritoneal adhesion in an experimental model.

BACKGROUND: Postoperative intra-abdominal adhesion is associated with high morbidity and mortality. Smad7, a protein that occupies a strategic position in fibrogenesis, inhibits the transforming growth factor (TGF) beta/Smad signalling pathway. In this study the therapeutic potential of exogenous Smad7 in preventing fibrogenesis in postoperative intra-abdominal adhesion was investigated. METHODS: Intra-abdominal adhesion was induced in a rodent model by peritoneal abrasion. Smad7 was delivered into the peritoneal cavity by a non-viral ultrasound-microbubble-mediated naked gene transfection system. The effect of Smad7 transgene on adhesion formation was studied by measuring changes in TGF-beta, fibrogenic factors, alpha-SMA and Smad2/3 activation in the anterior abdominal wall. RESULTS: Four weeks after surgical abrasion, all rats developed significant peritoneal adhesion with enhanced TGF-beta expression, increased levels of extracellular matrix components and activated myofibroblasts, accompanied by decreased Smad7 expression and increased Smad2/3 activation. In rats treated with the Smad7 transgene, the incidence and severity of peritoneal adhesion were significantly reduced, with biochemical downregulation of fibrogenic factors and inhibition of Smad2/3 activation. Serial quantitation using magnetic resonance imaging revealed a significant reduction in adhesion areas from day 14 onwards. CONCLUSION: Ultrasound-microbubble-mediated gene transfection provides timely targeted gene delivery for the treatment of postoperative peritoneal adhesions.

Temporal delays in incorporation of events into dreams.

20 subjects viewed an emotionally arousing video and then recorded their dreams at home for seven nights. Dreams were subsequently rated for the likelihood that some aspect of the video had been incorporated. For subjects who showed strong evidence of incorporation, mean likelihood of incorporation ratings followed a U-shaped pattern, with significantly higher scores on Nights 1, 6, and 7 than on Night 4. The similarity of this temporal pattern with REM sleep patterns observed in rats exposed to various learning experiences is noted, and the role of the hippocampus as a possible neural mechanism for delayed incorporations is discussed.

Discriminative facility and its role in the perceived quality of interactional experiences.

Discriminative facility refers to an individual's sensitivity to subtle cues about the psychological meaning of a situation. This research aimed at examining (a) the conceptual distinctiveness of discriminative facility, (b) the situation-appropriate aspect of this construct, and (c) the relationship between discriminative facility and interpersonal experiences. Discriminative facility was assessed by a new measure of situation-appropriate behaviors across a variety of novel stressful situations. Results from study 1 showed that discriminative facility had weak positive relationships with cognitive complexity and nonsignificant relationships with self-monitoring and social desirability, indicating that discriminative facility is a unique construct. Results from Study 2 revealed that higher levels of discriminative facility were associated with higher levels of perceived social support and a greater number of pleasant interpersonal events experienced, thus providing support for the theoretical proposition that discriminative facility is an aspect of social intelligence.