Pseudoathetosis: report of three patients.

We report on 3 patients with pseudoathetosis, which are involuntary, slow, writhing movements due to loss of proprioception.     

Application of a vibration measuring technique to evaluate the dynamic stiffness of porcine periodontal ligament.

The performance of a tooth replacement by using a dental implant relies on the mechanical and biological capability of the anatomical substitute to restore lost physiological functions. The design of an implant device able to properly replace the physiological tooth requires the study of the load transfer mechanism at the implant-bone interface and the understanding of the relevance of the periodontal ligament (PDL) in this mechanism. The PDL is a connective soft tissue that provides the fixation of the tooth in its bone-socket and the attenuation of occlusal loads. It also provides the ground cells that are involved in the remodelling process, induced by a change in the stress-strain pattern of the alveolar bone and also in the cementum of the tooth root. The purpose of this study was to determine the PDL effects on the dynamic load transfer mechanism, from the tooth to the alveolar bone, evaluating the equivalent dynamic stiffness of the ligament structure. A porcine fresh mandible with a tooth was used within the study, applying an experimental procedure to identify the dynamic transmissibility of the entire system. The transmissibility function provided information about the stiffness and damping of the PDL, information that can assist the design of an improved dental implant system.     

Pulmonary artery distensibility in pulmonary arterial hypertension: an MRI pilot study.

Pulmonary arterial hypertension (PAH) is a disease of the small vessels in which there is a substantial increase in pulmonary vascular resistance leading to right ventricle failure and death. Invasive haemodynamic evaluation is mandatory not only for diagnosis confirmation but also to address prognosis and eligibility for the use of calcium-channel blockers through an acute vasodilator challenge. Noninvasive surrogate response markers to the acute vasodilator test have been sought. In the present study, the relationship between pulmonary artery distensibility, assessed using magnetic resonance imaging (MRI), and response to acute vasodilator tests was investigated. In total, 19 patients diagnosed with idiopathic PAH without any specific treatment were evaluated. Within a 48-h window after pulmonary artery catheterisation, patients underwent cardiac MRI. Cardiac index, calculated after the determination (invasively and noninvasively) of cardiac output, showed excellent correlation, as did right atrial pressure and right ventricle ejection fraction. Pulmonary artery distensibility was significantly higher in responders. A receiver operating characteristic curve analysis has shown that 10% distensibility was able to differentiate responders from nonresponders with 100% sensitivity and 56% specificity. The present findings suggest that magnetic resonance imaging and pulmonary artery distensibility may be useful noninvasive tools for the evaluation of patients with pulmonary hypertension.