Commentary on the Article “Systematic Review and Meta-Analysis Comparing Prostatic Artery Embolisation to Gold-Standard Transurethral Resection of the Prostate for Benign Prostatic Hyperplasia”

CardioVascular and Interventional Radiology -     

The Source of Power Matters: Positional Power as a Better Predictor of Sexual Interest Perceptions than Dispositional Power Among Men within a Military Context

Archives of Sexual Behavior - The current research examined the roles of positional power induced by one’s hierarchical position in an organization and dispositional power (i.e., one’s...     

Primary auditory cortex representation of fear‐conditioned musical sounds

Auditory cortex is required for discriminative fear conditioning beyond the classical amygdala microcircuit, but its precise role is unknown. It has previously been suggested that Heschl's gyrus, which includes primary auditory cortex (A1), but also other auditory areas, encodes threat predictions during presentation of conditioned stimuli (CS) consisting of monophones, or frequency sweeps. The latter resemble natural prosody and contain discriminative spectro‐temporal information. Here, we use functional magnetic resonance imaging (fMRI) in humans to address CS encoding in A1 for stimuli that contain only spectral but no temporal discriminative information. Two musical chords (complex) or two monophone tones (simple) were presented in a signaled reinforcement context (reinforced CS+ and nonreinforced CS?), or in a different context without reinforcement (neutral sounds, NS1 and NS2), with an incidental sound detection task. CS/US association encoding was quantified by the increased discriminability of BOLD patterns evoked by CS+/CS?, compared to NS pairs with similar physical stimulus differences and task demands. A1 was defined on a single‐participant level and based on individual anatomy. We find that in A1, discriminability of CS+/CS? was higher than for NS1/NS2. This representation of unconditioned stimulus (US) prediction was of comparable magnitude for both types of sounds. We did not observe such encoding outside A1. Different from frequency sweeps investigated previously, musical chords did not share representations of US prediction with monophone sounds. To summarize, our findings suggest decodable representation of US predictions in A1, for various types of CS, including musical chords that contain no temporal discriminative information.     

Mechanical stability in a human radius fracture treated with a novel tissue‐engineered bone substitute: a non‐invasive,longitudinal assessment using high‐resolution pQCT in combination with finite element analysis

The clinical gold standard in orthopaedics for treating fractures with large bone defects is still the use of autologous, cancellous bone autografts. While this material provides a strong healing response, the use of autografts is often associated with additional morbidity. Therefore, there is a demand for off‐the‐shelf biomaterials that perform similar to autografts. Biomechanical assessment of such a biomaterial in vivo has so far been limited. Recently, the development of high‐resolution peripheral quantitative computed tomography (HR‐pQCT) has made it possible to measure bone structure in humans in great detail. Finite element analysis (FEA) has been used to accurately estimate bone mechanical function from three‐dimensional CT images. The aim of this study was therefore to determine the feasibility of these two methods in combination, to quantify bone healing in a clinical case with a fracture at the distal radius which was treated with a new bone graft substitute. Validation was sought through a conceptional ovine model. The bones were scanned using HR‐pQCT and subsequently biomechanically tested. FEA‐derived stiffness was validated relative to the experimental data. The developed processing methods were then adapted and applied to in vivo follow‐up data of the patient. Our analyses indicated an 18% increase of bone stiffness within 2 months. To our knowledge, this was the first time that microstructural finite element analyses have been performed on bone‐implant constructs in a clinical setting. From this clinical case study, we conclude that HR‐pQCT‐based micro‐finite element analyses show high potential to quantify bone healing in patients. Copyright © 2010 John Wiley & Sons, Ltd.