Notes: In this study, we evaluated safety and recovery using a patient maintained, target controlled infusion of propofol for sedation in 20 patients undergoing colonoscopy. Using a handset with a two-minute lockout interval, patients could make 0.2 µg.ml−1 increments to an initial target plasma concentration of 1 µg.ml−1 up to a maximum 4.5 µg.ml−1. Four patients became oversedated but required no airway or circulatory interventions. Subjects had a significant reduction in mean (SD) heart rate: 78.7 (15) vs. 69.8 (13.5) (p 〈 0.001) and in systolic blood pressure 121.1 (13.2) mmHg vs. 96.5 (8.6) mmHg (p 〈 0.001). Choice reaction time testing 15 min after colonoscopy showed a significant median (IQR [range]) rise of 162 (− 16, 383.3 [-199–859]) ms (p 〈 0.05). Six patients had faster reaction times postcolonoscopy. All patients denied unpleasant recall and were satisfied with the system. Although oversedation was a problem in this model, we conclude that patient maintained propofol sedation could be possible for colonoscopy.

Notes: Summary Background Caveolin-1 is a key structural and functional protein for plasmalemmal invaginations termed caveolae. Caveolin-1 is known to modulate multiple signal-transducing pathways involved in cell differentiation and proliferation. Psoriasis is viewed as a multifactorial pathology characterized by keratinocyte hyperproliferation and abnormal cell maturation. We hypothesized that loss of caveolin-1 within epidermal keratinocytes may contribute to the development and/or progression of the psoriatic phenotype. Objectives To examine the expression and spatial distribution of caveolin-1 in skin biopsies from normal subjects and in patients with psoriasis. Methods Using immunohistochemical methods caveolin-1 protein expression was assayed in two independent patient groups. Firstly, a retrospective analysis was conducted on archival skin samples obtained from nine normal subjects and from involved tissue of 12 patients with psoriasis. Following this, a prospectively designed study was conducted in 10 further patients with active psoriasis and involving caveolin-1 staining of biopsy tissue from the uninvolved, advancing edge and lesional skin tissue from within the same subject. Results In normal skin or uninvolved skin from psoriasis patients intense caveolin-1 staining was present throughout full-thickness epidermis. In 20 of the 22 patient cases (combined retrospective and prospective samples) caveolin-1 protein was significantly reduced and consistently showed very weak or absent staining within the hyperproliferative basal cell layers of the psoriatic plaque (P 〈 0·002 for retrospective archival study and P 〈 0·01 for prospectively designed study). Comparisons between caveolin-1 staining in uninvolved tissue and at the advancing edge of a migrating plaque were more equivocal (P 〉 0·05). Conclusions The findings of this study are consistent with a downregulation of caveolin-1 that may serve as an aetiological factor in the development and/or progression of psoriasis. Further mechanistic investigations are required with the potential that caveolin-1 protein may be a novel target for therapy of psoriasis.