Closed-loop administration of atracurium

The advent of newer muscle relaxants with predictable rates of metabolism and times of offset of neuromuscular blockade now makes it possible to use intravenous infusion safely as a mode of delivery. This has many advantages over administration by intermittent bolus. Moreover, it is feasible to use a servo system for their delivery. We have developed and evaluated such a system which is portable and requires little computer expertise to set up and use. It is a useful adjunct to routine anaesthesia, as well as a potentially powerful research tool.     

Assessment of invasive growth pattern and lymphocytic infiltration in colorectal cancer

A total of 122 specimens of colorectal cancer were re-assessed in relation to the reporting of invasive growth pattern (expanding vs. infiltrating) and presence or absence of peritumoral lymphocytic infiltrate as used in the Jass prognostic classification. Jass agreed with 69% of cases reported as infiltrating and 90% of those reported as expanding. This parameter was distributed similarly amongst Dukes B and C cases in the original assessment ( P  = 0.27), whereas in the reviewed data infiltrating cases were more likely to be staged as Dukes C ( P  = 0.04). Jass agreed with 44% of lymphocyte present and 94% of lymphocyte absent assessments. The original lymphocyte assessments showed no significant differences in distribution between Dukes A and B cases ( P  = 0.12) or B and C cases ( P  = 0.75), whereas the reviewed data showed significant differences for A vs. B ( P  = 0.015) and B vs. C cases ( P  = 0.0025). Criteria for assessment were circulated to eight observers who revisited 20 of the cases in which there was disagreement. Consensus agreement with Jass was achieved in nine of 10 cases for invasive growth pattern and seven of 10 cases for lymphocyte infiltration (with two being evenly split). Most observers showed at least fair levels of agreement with Jass and some achieved excellent levels of agreement. This study indicates that assessment of criteria used in the Jass prognostic system for colorectal cancer is less than optimal in routine practice, but is improved through the provision of simple guidelines.     

A study of parental age effects on the occurrence of fresh mutations for the Apert syndrome

A sample of 44 patients with the Apert syndrome was analysed for parental age effects on the occurrence of fresh mutations by using two conceptually similar techniques, one proposed by Smith (1972) and the other devised for the purposes of this study. The results of both analyses confirmed the parental age effect reported by Blank (1960), and was probably due solely to increased paternal age.