Anaplastic ameloblastic fibrosarcoma arising from recurrent ameloblastic fibroma: restricted molecular abnormalities of certain genes to the malignant transformation.

A rare case of anaplastic ameloblastic fibrosarcoma (AS) arising in an ameloblastic fibroma (AF) of the maxilla of a 48-year-old patient 10 years after the primary excision is presented. The recurrent tumor retained focal areas of AF but manifested heterogeneous malignant features ranging from low-grade spindle to highly pleomorphic sarcomas. Biomarker analysis showed alterations of the p53 and c-KIT genes restricted to the sarcomatous component. The biological implications of these findings in the future management of these tumors are discussed.     

重睑术

重睑术是美国最流行的美容外科手术，每年的手术人数达500000-600000之多。洛杉矶Jules Stein眼科研究所的Baylis医师说，1年做10例的医师可以与1年做200例其他医师一样熟练。Baylis医师估计，人群的25％企望做重险术。     

Development and reproducibility of a tool to assess school food-purchasing practices and lifestyle habits of Australian primary school-aged children

Objective: To describe the development and reproducibility of a self‐report instrument, for use with children in years 4–6, to identify sources of food eaten during the day, and type and frequency of food purchases at school. Design: Tool development stages included formulation of content and format, expert review, piloting and a test–retest study. Subjects/setting: The pilot study included school students (n = 20) in years 4 and 5 (seven girls, mean age 9.7 ± 0.7 years) attending an Australian public primary school. The test–retest study was performed in a large metropolitan public primary school (n = 245 children, 52% female, mean age 10.7 ± 0.91 years) including children from years 4 (n = 88), 5 (n = 84) and 6 (n = 73). Statistical analysis: A Kappa statistic was used to assess level of agreement between the two time periods separated by 1 week. The results were analysed using SAS version 8.2 with each question compared at time 1 and 2. Results: The mean kappa was 0.529 using pairings from 17 questions. Values ranged from 0.18 to 0.71 (CI 0.46–0.60). Conclusions and applications: The School Eating Habits and Lifestyle Survey has been developed and pilot‐tested in primary school‐aged children and shown to have moderate stability over time. The results show that each phase of development, particularly those spent in consultation and testing, led to progressive improvement of this instrument. This process improved the quality of information produced and gave insights to self‐report of dietary intake and behaviours among children.     

Reversible reorganisation of the motor cortical representation of the hand in cervical dystonia.

Previous work has suggested that there may be a widespread disturbance of motor control mechanisms in patients with cervical dystonia. In the present study, we used transcranial magnetic stimulation to investigate the topography of the corticomotor projection to the abductor pollicis brevis (APB) muscle in 10 subjects with idiopathic torticollis. Threshold-adjusted stimuli were delivered at multiple scalp sites during a low-level voluntary contraction of the APB, and maps were generated of motor evoked potential amplitude versus scalp site. The cortical maps for the APB on the side opposite to the direction of head rotation were displaced laterally or posteriorly in all subjects and reverted to a more normal position after botulinum toxin injection of the cervical muscles in 5 subjects. The findings point to a reversible reorganisation of the corticomotor representation of the hand on the same side as the sternocleidomastoid (SCM) muscle that is involved in producing the dystonia. These results provide further evidence for the involvement of cortical centres and for a more widespread abnormality of motor control mechanisms in focal dystonia. The findings also support the notion that head turning is chiefly mediated by the hemisphere ipsilateral to the direction of the head rotation by means of a corticomotor projection to the contralateral SCM.     

Perceived mistreatment of graduating dental students: a retrospective study.

This study assessed types and sources of perceived mistreatment among graduating dental students. A total of 38 of 46 (83 percent) students anonymously completed a mistreatment questionnaire. All 38 students perceived experiencing at least one type of mistreatment from some source and reported an average of about 35 separate incidents. Psychological mistreatment was most frequent with physical mistreatment reported relatively infrequently. Classmates and clinical faculty were the most frequent sources of mistreatment. Sexual harassment was perceived by about one-third of the students. The potentially adverse effects of perceived mistreatment were discussed with a view to improving dental education through an emphasis on stress management, environmental change, and self-responsibility for health designed to enhance the personal growth of each dental student.     

Reproducibility of lateral spine scans using dual energy X-ray absorptiometry

Summary Reproducibility of lateral spine dual energy X-ray absorptiometry (LAT DEXA) scans using a Lunar DPX-L scanner was assessed in a cadaveric phantom and in patients. One hundred phantom measurements over 7 months demonstrated a longitudinal stability of 1.7% (coefficient of variation, CV). Additional scans were performed with the phantom rotated by up to 20° in each of the three orthogonal planes to assess the effects of variable patient positioning. Horizontal and vertical rotation of the spine had little effect on the estimated bone mineral density (BMD), however, axial rotation of greater than 8° led to errors in the BMD measurement. One hundred consecutive patients had two lateral scans performed within 1 month. BMD (range 0.10–1.6 g/cm²) was determined for each scan by one operator. Significant overlap from ribs and pelvis was often seen with L2 and L4 vertebrae but one vertebra (L3) could be measured in every case. Intraoperator and interoperator variability was assessed by three experienced operators, each analyzing 10 patients' scans on five separate occasions, and was found to be less than 1.1% for a single vertebra. BMD estimation of vertebral bodies and midslices by lateral DEXA scans (CV% of 3.8% and 4.6%) have a 95% confidence interval of 0.074 g/cm² and 0.096 g/cm², respectively for two vertebrae. This variability is due mainly to axial rotation, with operator variability, horizontal rotation, and vertical rotation having little effect on BMD estimation.