Contribution of magnetic resonance spectrometry to the diagnosis of intracranial tumors

Magnetic resonance spectroscopy (MRS) is a method enabling the analysis of the tissue metabolic content. It may offer a more accurate diagnosis of the intracranial tumors than conventional MRI sequences. MRS of normal brain parenchyma displays 4 main metabolites: N-acetyl aspartate (neuronal marker), creatine (cellular density marker), choline (membrane activity marker) and myoinositol (glial marker); pathological processes lead to variations of the level of these metabolites and/or the appearance of abnormal metabolites (lactate), following different patterns according to pathological process involved: glioma, meningioma, metastasis, bacterial or toxoplasmic abscess, radionecrosis. The potential clinical use of this method includes positive, differential and etiological diagnosis of tumors, determination of the level of malignancy of gliomas, screening for tumor recurrence following treatment. Our laboratory has been performing MR spectroscopic explorations of brain tumors for many years. Based on this experience, we show how MRS can be routinely performed in the clinical setting, what are its limitations and potential, and what kind of information can be supplied to the clinician.     

北京市40家基层医院高血压防治硬件条件的现状调查

目的 了解北京市基层一、二级医院高血压诊断治疗相关辅助检查设备以及抗高血压药物的拥有和使用现状,评估基层医院开展高血压防治工作的能力。从医院硬件条件(辅助检查设备、药物等)的角度分析基层医院实施《中国高血压防治指南》(以下简称《指南》)的过程中可能存在的障碍和问题。方法 采用面访和问卷调查的方式,访问北京市部分基层医院主管业务的院长以及检验科、药房、影像科的相关业务主管,了解医院高血压相关辅助检查设备及用药情况。结果 (1)被调查的二级医院现有的设备条件基本能够满足《指南》提出的对高血压患者进行临床评估的要求;(2)64．5％的一级医院具有开展高血压防治所需要的最基本的设备和检查项目,35．5％的一级医院检查项目不全(缺少血离子、尿蛋白、血浆肌酐浓度等检测);(3)71．0％的一级医院无法独立完成患者靶器官损害的评估工作;(4)一、二级医院抗高血压药物的种类比较齐全,可以满足患者治疗的需要。结论 只要相关实验室检查项目配备齐全,基层医院完全有能力按照《指南》的要求开展高血压的治疗和疗效监测工作,但一级医院需要和上级医院配合才能完成对高血压患者全面的临床评估。     

The reversed Delta shoulder prosthesis in reconstruction of the proximal humerus after tumour resection

The authors present two series of six and seven patients respectively, with a tumour of the proximal humerus, who were treated at two different institutions with a Delta type inverted shoulder prosthesis (DePuy International Ltd) after a Malawer type Ia or Ib resection. The rationale of using an inverted shoulder prosthesis is the aim to improve the functional outcome in rotator cuff deficient shoulders. This type of prosthesis medializes and lowers the centre of rotation, lengthens the lever arm of the deltoid muscle and improves its function. At one institution the resected part of the humerus was re-implanted after extracorporeal irradiation. It was fixed intramedullarly by cementation of the humeral prosthetic component to facilitate restoration of humeral height. This graft allowed reinsertion of muscles (deltoid, pectoralis, biceps) thus improving power generation postoperatively. The largest glenosphere, size 42, was routinely used to reconstruct the glenoid; this theoretically improves the functional outcome (increased external rotation) and stability. At the other institution no graft augmentation was used except in one patient. The height of the humeral prosthetic component was assessed after resection of the tumour by measurement of the resected part. The prosthetic stem was fitted in the remaining part of the humeral diaphysis, in three cases by cementation and in three cases by press-fit (hydroxyapatite coating). Muscle balance was appreciated intra-operatively. Stability of the prosthesis was directly related to the level of resection. Both techniques resulted in a minimum active abduction of 60 degrees, reaching 90 degrees or more in most patients. When compared to other results in the literature, this is a major functional improvement. The mean adjusted postoperative Constant score was 72.5% (range: 30-90%), and the mean MSTS score was 75.8% (range 36.7-96.7%).     

Resveratrol analog (Z)-3,5,4'-trimethoxystilbene is a potent anti-mitotic drug inhibiting tubulin polymerization

Resveratrol (3,5,4'-trihydroxystilbene) a natural polyphenol present in medicinal plants, grapes and wines, has potent chemopreventive properties on intestinal carcinogenesis. A methylated derivative (Z-3,5,4'-trimethoxystilbene: R3) was synthesized. R3 at 0.3 microM exerted a 80% growth inhibition of human colon cancer Caco-2 cells and arrested growth completely at 0.4 microM (R3 was 100-fold more active than resveratrol). The cis conformation of R3 was also 100-fold more potent than the trans isomer. R3 (0.3 microM) caused cell cycle arrest at the G2/M phase transition. The drug inhibited tubulin polymerization in a dose-dependent manner (IC50=4 microM), and it reduced also by 2-fold ornithine decarboxylase and s-adenosylmethionine decarboxylase activities. This caused the depletion of the polyamines, putrescine and spermidine, which are growth factors for cancer cells. R3 inhibited partially colchicine binding to its binding site on tubulin, indicating that R3 either partially overlaps with colchicine binding or that R3 binds to a specific site of tubulin that is not identical with the colchicine binding site modifying colchicine binding by allosteric influences. The resveratrol derivative (Z)-3,5,4'-trimethoxystilbene (R3) is an interesting anti-mitotic drug that exerts cytotoxic effects by depleting the intracellular pool of polyamines and by altering microtubule polymerization. Such a drug may be useful for the treatment of neoplastic diseases.     

Orthodontic Space Closure without Contralateral Extraction through Mesial Movement of Lower Molars in Patients with Aplastic Lower Second Premolars

METHOD AND PATIENTS: A method is presented that allows unilateral space closure in patients with aplastic lower second premolars. Based on a straight-wire appliance, space closure was achieved with a combination of "push mechanics" using the second molar as an anchorage unit and Class II "pull mechanics", thus avoiding the application of any distalizing force on the lower incisors. The results from 13 consecutively treated subjects (five boys, eight girls, mean age 12 years and 6 months) were analyzed. RESULTS: Complete bodily space closure was achieved in all 13 cases within a mean treatment time of 2 years and 7 months. The desired Angle Class III molar relationship of one premolar width (+/- 1/4 premolar width) on the aplastic side was successful in eleven patients, an additional 4.7 mm of space being created for the third molar on the aplastic side compared with the contralateral side (p < or = 0.01). However, adverse effects could be kept to a minimum, with no method-dependent side effects being recorded with regard to canine and molar relationships on the contralateral side, or to overbite, overjet, or upper and lower incisor inclination. The mean lower midline shift of 0.8 mm was in accordance with the mean distal canine relationship of 1/3 premolar width on the aplastic side. CONCLUSION: These results confirm that orthodontic space closure in cases of unilateral aplastic lower second premolars can be performed successfully with the presented treatment method without the need for additional premolar extractions, prosthodontic treatment or implants. Furthermore, the prognosis for the lower wisdom tooth on the aplastic side is improved.     

Acute disseminated encephalomyelitis cohort study: prognostic factors for relapse.

To date, there is no available epidemiological study about prognostic factors of acute disseminated encephalomyelitis (ADEM) in children, using a cohort of patients with homogenous inclusion criteria. We aimed to evaluate prognostic factors for relapse after ADEM in children. A total of 132 children from the French National KIDSEP Neuropediatric Cohort (mean age at onset: 6+/-3.3 years; mean follow-up: 5.4+/-3.3 years; lost to follow-up: 10%). ADEM diagnosis was considered in a previously healthy patient acutely presenting more than one neurological deficit, change in mental state and MRI alterations including white matter changes. We used multivariate survival analysis (Cox model) evaluating the prognostic value of baseline clinical, biological and MRI covariates, for the occurrence of a second attack. Twenty-four (18%) of included patients had a second attack. An increased risk of relapse was associated with optic neuritis (hazard ratio, 5.23; 95% CI, 2-13.65), familial history of central nervous system inflammatory demyelination (7.79; 1.54-39.5), Barkhof multiple sclerosis (MS) criteria on MRI (2.52; 1.04-6.12) and no neurological sequelae after first attack (3.79; 1.12-12.85). Clinical and MRI prognostic factors for relapse in ADEM may contribute to an early distinction between monophasic and relapsing disease, which may be related to MS.