An integrated coronary circulation teaching model.

Objectives: We present in this paper a model of the coronary circulation. This model is integrated with a model of the systemic circulation, and contains models for oxygen supply and demand.

Methods: Three compartments are created: one for the right ventricle, one for the epicardial segment of the left ventricle and one for the endo-cardial segment of the left ventricle.

A model for educational simulation of infant cardiovascular physiology.

Full-body patient simulators provide the technology and the environment necessary for excellent clinical education while eliminating risk to the patient. The extension of simulator-based training into management of basic and critical situations in complex patient populations is natural. We describe the derivation of an infant cardiovascular model through the redefinition of a complete set of parameters for an existing adult model.

RNA recognition and base flipping by the toxin sarcin.

Sarcin is a member of a fungal toxin family that enters cells and specifically cleaves one of the thousands of RNA phosphodiester bonds in the ribosome. As a result, elongation factor binding is disrupted, translation is inhibited and apoptosis is triggered. The toxin targets a universal RNA structure in the ribosome called the sarcin/ricin loop (SRL).

The common and the distinctive features of the bulged-G motif based on a 1.04 A resolution RNA structure.

Bulged-G motifs are ubiquitous internal RNA loops that provide specific recognition sites for proteins and RNAs. To establish the common and distinctive features of the motif we determined the structures of three variants and compared them with related structures. The variants are 27-nt mimics of the sarcin/ricin loop (SRL) from Escherichia coli 23S ribosomal RNA that is an essential part of the binding site for elongation factors (EFs).

A new approach to mechanical simulation of lung behaviour: pressure-controlled and time-related piston movement.

A mechanical lung simulator is described (an extension of a previous mechanical simulator) which simulates normal breathing and artificial ventilation in patients. The extended integration of hardware and software offers many new possibilities and advantages over the former simulator. The properties of components which simulate elastance and airway resistance of the lung are defined in software rather than by the mechanical properties of the components alone.