Paget disease with contraction of long bones

The evolution of Paget disease characterized both by expansion and subsequent contraction of the long bones of the ipsilateral upper extremity over a 10-year period is described.     

Backscattering from dental restorations and splint materials during therapeutic radiation

Models were constructed to simulate as closely as possible the human oral cavity. Radiation absorbed doses were determined for controls and various test situations involving the presence of dental restorative and splint materials during cobalt-60 irradiation of the models. Adjacent gold full crowns and adjacent solid dental silver amalgam cores both increased the dose to the interproximal gingivae by 20%. Use of orthodontic full bands for splinting the jaws increased the dose to the buccal tissues by an average of 10%. Augmentation of dose through backscatter radiation was determined to be only slight for intracoronal amalgam fillings and stainless steel or plastic bracket splints.     

Thymus dysfunction and chronic inflammatory disease in gp39 transgenic mice

Expression of gp39 on activated T cells provides a co-stimulatory signal in peripheral lymphoid tissue that regulates humoral and cell- mediated immunity. The function of gp39 and its receptor CD40 in thymus remains uncertain. Here we report that overexpression of gp39 in transgenic mouse thymus caused a dose-dependent decline in thymocyte numbers (> 500 fold), loss of cortical epithelium and expansion of CD40+ medullary cells. Transplantation of transgenic bone marrow into normal mice indicated that gp39 significantly diminished thymocyte viability in the context of a 'normal' thymic environment. The peripheral tissues of transgenic mice also accumulated abnormalities in a transgene dose-dependent manner that involved inflammation and lymphoid tissue hypertrophy. Animals with the highest transgene copy numbers acquired a lethal inflammatory bowel disease marked by the infiltration of gp39+ T cells and CD40+ cells into diseased tissues. Examination of cells overexpressing gp39 suggested that these defects were caused, in part, by the saturation of a mechanism that sequesters gp39 inside non-activated cells and thus protects the immune system from inappropriate gp39-CD40 interaction. These results establish a regulatory role for gp39 in thymus function and a causal relationship in mediating chronic inflammatory disease.      

Circle of Willis artery diameters on MR angiography: An Australian reference database

The aim was to establish a reference range of measurements for all major Circle of Willis (COW) arteries for an Australian population of patients presenting for brain magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) that is typical of a tertiary referral hospital; and to report the prevalence and disease associations of COW variants in our patient population. All technically diagnostic MRI and MRA studies performed at our magnetic resonance (MR) centre in the calendar year 2006 were re‐read by one reader who classified the COW anatomical layout and measured diameters of all the major vessels at defined locations. A subset of 30 was independently re‐read by another reader and the interobserver measurement variability analyzed. Graphical analysis, with 95% confidence intervals (95CI), summary statistics reporting, t‐testing for unpaired and for paired means, Hauck‐Anderson (H‐A) clinical equivalence testing and logistic regression analysis for categorical variables was performed as relevant. One hundred and seventy‐one studies (of 187 eligible) formed the analysis population. All of our patients had vessels of comparable calibre regardless of MRI disease status, gender or COW variant (P > 0.05). Basilar artery (BA) diameter showed significant association with age, but other vessel diameters did not. The reference range is widely applicable, methodology straightforward and appears tolerant of interobserver variability. A number of discontinuous COW variants become more prevalent with age, perhaps from atherosclerotic occlusive disease. There was no association between COW variants, gender, aneurysm location or MRI disease status.     

The impact of late acute rejection after cadaveric kidney transplantation

BACKGROUND: Acute graft rejection (AR) following renal transplantation results in reduced graft survival. However, there is uncertainty regarding the definition, aetiology and long-term graft and patient outcome of AR occurring late in the post-transplant period. AIM: To determine if rejection episodes can be classified by time from transplantation by their impact on graft survival into early acute rejection (EAR) and late acute rejection (LAR). MATERIALS AND METHODS: 687 consecutive adult renal transplant recipients who received their first cadaveric renal transplant at a single centre. All received cyclosporine (CyA)-based immunosuppression, from 1984 to 1996, with a median follow-up of 6.9 yr. Details were abstracted from clinical records, with emphasis on age, sex, co-morbid conditions, HLA matching, rejection episodes, patient and graft survival. ANALYSIS: Patients were classified by the presence and time to AR from the date of transplantation. Using those patients who had no AR (NAR) as a baseline, we determined the relative risk of graft failure by time to rejection. The characteristics of patients who had no rejection, EAR and LAR were compared. RESULTS: Compared with NAR, the risk of graft failure was higher for those patients who suffered a rejection episode. A much higher risk of graft failure was seen when the first rejection episode occurred after 90 d. Thus, a period of 90 d was taken to separate EAR and LAR (relative risk of 3.06 and 5.27 compared with NAR as baseline, p<0.001). Seventy-eight patients (11.4%) had LAR, 271 (39.4%) had EAR and 338 (49.2%) had NAR. The mean age for each of these groups differed (LAR 39.6 yr, EAR 40.8 yr compared with NAR 44 yr, p<0.003). The 5-yr graft survival for those who had LAR was 45% and 10-yr survival was 28%. HLA mismatches were more frequent in those with EAR vs. NAR (zero mismatches in HLA-A: 36 vs. 24%, HLA-B: 35 vs. 23% and HLA-DR: 63 vs. 41%, p<0.003). There was no difference in mismatching frequency between NAR and LAR. CONCLUSIONS: AR had a deleterious impact on graft survival, particularly if occurring after 90 d. AR episodes should therefore be divided into early and late phases. In view of the very poor graft survival associated with LAR, it is important to gain further insight into the main aetiological factors. Those such as suboptimal CyA blood levels and non-compliance with medication should be further investigated with the aim of developing more effective immunosuppressive regimens in order to reduce the incidence of LAR.     

中耳炎

中耳炎是儿童的高发病.中耳炎的病因病理是多因素的,包含免疫反应、咽鼓管功能障碍、细菌和病毒的感染、遗传以及环境因素等.早期的观察适用于大多数中耳炎儿童;对于被确诊为急性中耳炎的两岁以内的患儿,建议使用抗生素.手术方法的选择取决于合并症、儿童的生长发育状况以及对自发性渗出液的预期估计.推荐的手术方法有鼓室置管术、腺样体刮除术等.然而,到目前还没有理想的治疗方法,需要探索新的、基于现代中耳炎的病因病理理论的有创意性的治疗方法.