Development of the human temporomandibular joint.

A great deal of research has been published on the development of the human temporomandibularjoint (TMJ). However, there is some discordance about its morphological timing. The most controversial aspects concern the moment of the initial organization of the condyle and the squamous part of the temporal bone, the articular disc and capsule and also the cavitation and onset of condylar chondrogenesis. Serial sections of 70 human specimens between weeks 7 and 17 of development were studied by optical microscopy (25 embryos and 45 fetuses). All specimens were obtained from collections of the Institute of Embryology of the Complutense University of Madrid and the Department of Morphological Sciences of the University of Granada. Three phases in the development of the TMJ were identified. The first is the blastematic stage (weeks 7-8 of development), which corresponds with the onset of the organization of the condyle and the articular disc and capsule. During week 8 intramembranous ossification of the temporal squamous bone begins. The second stage is the cavitation stage (weeks 9-11 of development), corresponding to the initial formation of the inferior joint cavity (week 9) and the start condylar chondrogenesis. Week 11 marks the initiation of organization of the superior joint cavity. And the third stage is the maturation stage (after week 12 of development). This work establishes three phases in TMJ development: 1) the blastematic stage (weeks 7-8 of development); 2) the cavitation stage (weeks 9-11 of development); and 3) the maturation stage (after week 12 of development). This study identifies the critical period of TMJ morphogenesis as occurring between weeks 7 and 11 of development.     

Compressed sensing in hyperpolarized 3He Lung MRI

In this work, the application of compressed sensing techniques to the acquisition and reconstruction of hyperpolarized ³He lung MR images was investigated. The sparsity of ³He lung images in the wavelet domain was investigated through simulations based on fully sampled Cartesian two‐dimensional and three‐dimensional ³He lung ventilation images, and the k‐spaces of 2D and 3D images were undersampled randomly and reconstructed by minimizing the L1 norm. The simulation results show that temporal resolution can be readily improved by a factor of 2 for two‐dimensional and 4 to 5 for three‐dimensional ventilation imaging with ³He with the levels of signal to noise ratio (SNR) (～19) typically obtained. The feasibility of producing accurate functional apparent diffusion coefficient (ADC) maps from undersampled data acquired with fewer radiofrequency pulses was also demonstrated, with the preservation of quantitative information (mean ADC_cs ～ mean ADC_full ～ 0.16 cm² sec^?1). Prospective acquisition of 2‐fold undersampled two‐dimensional ³He images with a compressed sensing k‐space pattern was then demonstrated in a healthy volunteer, and the results were compared to the equivalent fully sampled images (SNR_cs = 34, SNR_full = 19). Magn Reson Med 63:1059–1069, 2010. © 2010 Wiley‐Liss, Inc.     

Effect of ezetimibe–simvastatine over endothelial dysfunction in dyslipidemic patients: Assessment by <Superscript>13</Superscript>N-ammonia positron emission tomography

Background  

Dyslipidemias constitute an independent risk factor for the development of atherogenesis and they also predispose to the development of endothelial dysfunction (ED). Using PET with ¹³N-ammonia, it is possible to quantify myocardial blood flow (MBF) in mL/min/g and to quantitatively evaluate ED. With the use of lipid lowering therapy it is possible to reduce ED and increase the MBF and the endothelial-dependent vasodilation index (ENDEVI). In this study, we aimed to evaluate with ¹³N-ammonia PET the benefic effects of the combined treatment ezetimibe/simvastatine on the endothelial function of dyslipidemic patients after 8 weeks of treatment.     

A primary care cardiovascular risk reduction clinic in Canada was more effective and no more expensive than usual on-demand primary care – a randomised controlled trial

The objective of this randomised controlled trial was to compare the effects and expense of three approaches to care (1) proactive cardiovascular risk reduction (CaRR) clinic; (2) nurse telephone calls; or (3) usual care for people with cardiovascular risk factors in a Primary Care, Health Service Organisation (HSO) in Ontario, Canada. Subjects included consenting patients with an identified cardiovascular disease (CVD) risk factor identified from the HSO computerised patient information system in 2004. Patients were excluded if they were mentally incompetent, <18 years of age, in a nursing home, or not English speaking. Of 1570 eligible subjects, 523 (33.3%) verbally declined, 145 (9.2%) could not be contacted, and 249 (15.9%) were not needed. The final sample size was 653 (41.6%), 634 completed the follow-up (97%). The Cardiovascular Risk Score, Health and Social Service Utilisation, Montgomery-Asberg Depression Rating, Billings and Moos Indices of Coping, Personal Resource and Self-Efficacy Questionnaires were measured at baseline and 1-year follow-up by clinical examination and telephone interview. Cardiovascular risk scores were reduced in all treatment groups after 1 year. The proportions of subjects showing reduction in risk score greater than or equal to 10% was greatest in the CaRR group (69.2%) compared with Nurse Phone intervention (57.8%) and Usual Care (59.0%) ( M - H χ² = 4.33, df = 1, P  = 0.037, CaRR-Usual Care). Self-efficacy scores showed the greatest improvements in the CaRR clinic. This effect was achieved with no significant difference in total person per annum costs for direct and indirect health and social service utilisation between all three groups. A CaRR clinic is more effective in reducing CVD risk after 1 year compared with nurse phone intervention and usual care with no additional expense found.