No abstract

Ann R Coll Surg Engl 2006; 88: 116-121 116Rotator cuff tears are a common problem causing significant morbidity in terms of pain, activity limitation and sleep disturbance. A wide variation in the prevalence of cuff tears have been reported in cadaveric and radiological studies; as with other tendon failure, it is likely that this increases with age. The population in cadaveric studies tends to be older than the general population; consequently, a higher prevalence of cuff tears is likely. Furthermore, as no clinical data are available for the cadaveric population, it is reasonable to assume that, as in any large sample, some had symptomatic shoulders. The prevalence of rotator cuff tear in asymptomatic subjects determined by magnetic resonance imaging (MRI) and ultrasonography should be lower than the cadaveric population. Conversely, the radiological prevalence of rotator cuff tears in a population with symptomatic shoulders should be higher. This study reviewed the literature in an attempt to test this hypothesis. Patients and MethodsA Medline search was performed using the key words: rotator cuff tear, prevalence, cadaver, MRI and ultrasound. The search was widened using references from these articles. All publications up to the time of the search were used.The results were split into the following categories: cadaveric studies, ultrasound studies and MRI studies. The radiological studies were further categorised into asymptomatic and symptomatic.Data were collected on the total number of shoulders, the mean age of the group, the sex distribution, the number TRAUMA/ORTHOPAEDICS

Abstract. The Long-Wavelength Spectrometer (LWS) is one of two complementary spectrometers aboard the European Space Agency's Infrared Space Observatory 1 (ISO) (Kessler et al., 1996). It operates over the wavelength range 43 196:9 m at either medium (about 150 to 200) or high (6800 to 9700) spectral resolving power. This Letter describes the instrument and its modes of operation; a companion paper describes its performance and calibration.Send offprint requests to: P.E. Clegg (p.e.clegg@qmw.ac.uk) ? ISO is an ESA project with instruments funded by ESA Member States (especially the PI countries: France Germany, the Netherlands and the United Kingdom) and with the participation of ISAS and NASA.

Communication between endothelial and bone cells is crucial for controlling vascular supply during bone growth, remodeling, and repair but the molecular mechanisms coordinating this intercellular crosstalk remain ill-defined. We have used primary human and rat long bone-derived osteoblast-like cells (HOB and LOB) and human umbilical vein endothelial cells (HUVEC) to interrogate the potential autocrine/paracrine role of vascular endothelial cell growth factor (VEGF) in osteoblast:endothelial cell (OB:EC) communication and examined whether prostaglandins (PG), known modulators of both OB and EC behavior, modify VEGF production. We found that the stable metabolite of PGI2, 6-keto-PGF(1alpha) and PGE2, induced a concentration-dependent increase in VEGF release by HOBs but not ECs. In ECs, VEGF promoted early ERK1/2 activation, late cyclooxygenase-2 (COX-2) protein induction, and release of 6-keto-PGF1alpha. In marked contrast, no significant modulation of these events was observed in HOBs exposed to VEGF, but LOBs clearly exhibited COX-dependent prostanoid release (10-fold less than EC) following VEGF treatment. A low level of osteoblast-like cell responsiveness to exogenous VEGF was supported by VEGFR2/Flk-1 immunolabelling and by blockade of VEGF-mediated prostanoid generation by a VEGFR tyrosine kinase inhibitor (TKI). HOB alkaline phosphatase (ALP) activity was increased following long-term non-contact co-culture with ECs and exposure of ECs to VEGF in this system further increased OB-like cell differentiation and markedly enhanced prostanoid release. Our studies confirm a paracrine EC-mediated effect of VEGF on OB-like cell behavior and are the first supporting a model in which prostanoids may facilitate this unidirectional VEGF-driven OB:EC communication. These findings may offer novel regimes for modulating pathological bone remodeling anomalies through the control of the closely coupled vascular supply.