Transcatheter Aortic Valve Implantation in the Elderly: Who to Refer?

In recent years, experience with transcatheter aortic valve implantation has led to improved outcomes in elderly patients with severe aortic stenosis (AS) who may not have previously been considered for intervention. These patients are often frail with significant comorbid conditions.     

The use of operant self-control procedures in the treatment of compulsive hair-pulling

Two young female patients with a 10-and 5-year history of compulsive hair pulling were individually treated by the same operant self-control procedure. Zero pulling was achieved at weeks 6 and 13, and maintained at follow-up 15 months later. These findings are discussed in the light of previous behavioural treatments, and the importance of eliciting an appropriate aversive consequence for habit control is stressed.     

QSAR analysis of 1,3-diaryl-4,5,6,7-tetrahydro-2H-isoindole derivatives as selective COX-2 inhibitors

Quantitative structure-activity relationship (QSAR) analysis was performed on a series of 1,3-diaryl-4,5,6,7-tetrahydro-2H-isoindole for their cyclooxygenase-2 (COX-2) inhibition. QSAR investigations were based on Hansch's extra thermodynamic multi-parameter approach and receptor surface analysis (RSA). QSAR investigations reveal that steric and electrostatic interactions are primarily responsible for COX-2 enzyme-ligand interaction. QSAR model derived from Hansch analysis demonstrated that COX-2 inhibitory activity is correlated with sum of atomic polarizability (Apol), number of hydrogen-bond donor groups (HBD), energy of the highest occupied molecular orbital (HOMO), desolvation free energy for water (F(H(2)O)) and fraction of areas of molecular shadow in the XY and ZX planes over area of enclosing rectangle (Sxyf and Sxzf) with r ranges 0.870-0.904. The best model was obtained from RSA model having r = 0.940 with good predictive ability (predicted compounds in training set and test set within +/- 1.0 unit of pIC(50)) and can be used in designing better selective COX-2 inhibitors among the congeners in future.     

A usability evaluation of four commercial dental computer-based patient record systems

BackgroundThe usability of dental computer-based patient record (CPR) systems has not been studied, despite early evidence that poor usability is a problem for dental CPR system users at multiple levels.MethodsThe authors conducted formal usability tests of four dental CPR systems by using a purposive sample of four groups of five novice users. The authors measured task outcomes (correctly completed, incorrectly completed and incomplete) in each CPR system while the participants performed nine clinical documentation tasks, as well as the number of usability problems identified in each CPR system and their potential relationship to task outcomes. The authors reviewed the software application design aspects responsible for these usability problems.ResultsThe range for correctly completed tasks was 16 to 64 percent, for incorrectly completed tasks 18 to 38 percent and for incomplete tasks 9 to 47 percent. The authors identified 286 usability problems. The main types were three unsuccessful attempts, negative affect and task incorrectly completed. They also identified six problematic interface and interaction designs that led to usability problems.ConclusionThe four dental CPR systems studied have significant usability problems for novice users, resulting in a steep learning curve and potentially reduced system adoption.Clinical ImplicationsThe significant number of data entry errors raises concerns about the quality of documentation in clinical practice.