Dosimetric analysis of tomotherapy-based intensity-modulated radiotherapy with and without bone marrow sparing for the treatment of cervical cancer

Objective The aim of the study was to compare tomotherapy-based bone marrow-sparing intensity-modulated radiotherapy(BMS-IMRT) with intensity-modulated radiotherapy(IMRT) without entering the pelvic bone marrow as a planning constraint in the treatment of cervical cancer after hysterectomy. Methods BMS-IMRT and IMRT plans were designed for a cohort of nine patients. The prescribed dose was 45 Gy in 1.8 Gy daily fractions, and 95% of the planned target volume received this dose. The doses were computed using a commercially available treatment planning system with the convolution/superposition algorithm. Plans were compared according to dose-volume histogram analysis in terms of planning target volume homogeneity and conformity indices(HI and CI) as well as organ at risk dose and volume parameters. Results BMS-IMRT had advantages over IMRT in terms of CI, but was equivalent to the latter in HI. V5, V10, V20, V30, and V40 of pelvic bone marrow in BMS-IMRT decreased by 0.06%, 17.33%, 22.19%, 13.85%, and 16.46%, respectively, compared with IMRT. Except for V30 of the small bowel and V30 and V40 of the bladder, no statistically significant differences were found between BMS-IMRT and IMRT in the small bowel, bladder, and rectum. Conclusion For cervical cancer patients receiving tomotherapy-based radiotherapy after hysterectomy, BMS-IMRT reduced pelvic bone marrow volume receiving low-dose radiation, and it may be conducive to preventing acute hematologic toxicity.     

Evaluation of foramen magnum in gender determination using helical CT scanning

Objective

The present research was undertaken to study the accuracy and reliability of the foramen magnum (FM) and some cranial measurements in gender classification through the use of reconstructed helical CT images.

Methods

88 patients (43 males and 45 females; age range, 20–49 years) were selected for this study. FM sagittal diameter, transverse diameter, area and circumference were measured and data were subjected to discriminant analysis for gender using multiple regression analysis.

Results

FM circumference and area were the best discriminant parameters that could be used to study sexual dimorphism with an overall accuracy of 67% and 69.3%, respectively. By using multivariate analysis, 90.7% of FM dimensions of males and 73.3% of FM dimensions of females were sexed correctly.

Conclusion

It can be concluded that the reconstructed CT image can provide valuable measurements for the FM and could be used for sexing when other methods are inconclusive.     

ToMoTHERAPY螺旋断层放射治疗的现状与应用前景

本文以Wisconsin大学Madison医院开发的螺旋断层治疗技术为依据介绍螺旋断层治疗系统,阐述了螺旋断层放射治疗在以图像引导为特征的肿瘤放疗中的重要地位和发展前景。     

Ventricular Structure and Surgical History

The Reviews report will establish guidelines that underlie why the restoration concept may develop a paradigm shift in thinking, by addressing the geometric underpinnings of heart failure and their evolution. This presentation will (a) show that the underlying structure of the failing dilated heart involves a cardiac architectural change from the normal elliptical shape toward a dilated spherical form, (b) define the anatomic framework of this shape change, (c) convey the functional characteristics of heart function that result from this architectural underpinning, (d) describe the pattern of CHF development, (e) indicate imaging measurement guidelines to follow as heart form adversely changes from ellipse to sphere, (f) identify how such architectural changes alter prognosis, and (g) develop a historical evolution of surgical approaches to alter form to improve function to create the background for subsequent RESTORE team reports of current restoration to treat CHF and its complications.     

螺旋聚苯乙炔膜的制备及其气体透过性能

利用非手性((nbd)Rh+［η6-(C6H5)B-(C6H5)3］)为催化剂,将3种手性苯乙炔单体与非手性苯乙炔单体按照不同的比例进行共聚,得到了高分子量的可溶苯乙炔共聚物。将得到共聚物利用溶剂挥发法进行制膜,然后采用圆二色光谱仪(CD)对共聚物的二级结构进行测试。结果表明：该膜对CO2有优先透过性能,共聚物主链上形成单手性螺旋结构。     

螺旋CT在外科疑难急腹症中的诊断价值

目的探讨螺旋CT在外科疑难急腹症中的诊断价值。方法自身对照研究分析2003年3月～2004年11月外科疑难急腹症患者147例,比较螺旋CT检查前后的诊断、治疗方案、手术符合率。结果147例疑难急腹症患者通过16排螺旋CT检查后,50.3%的患者改变了原先的诊断与治疗计划,33.33%的患者完全改变原初的诊断和治疗方案。结论螺旋CT能够提高外科疑难急腹症诊治水平。     

多层螺旋CT曲面重建技术在胆总管扩张诊断中的应用

目的:研究胆总管扩张螺旋CT曲面重建技术(CPR)的操作方法、临床应用价值及其局限性。方法:收集20例胆总管扩张患者,将其1～3mm薄层扫描轴位源像(ASI)传到工作站后处理,行扩张胆总管曲面重建成像,作任意曲面显示所要观察的扩张胆总管。经手术病理及随访证实,评估CPR对胆总管扩张病因的定位与定性价值。结果:CPR对扩张胆总管的成像率达100%,均能显示完整的扩张胆总管及梗阻部位,定位准确率达100%,定性准确率达90%。结论:CPR能将不在同一平面的扩张胆总管显示于一个平面上,更好地显示扩张胆总管的连续性,可直观地显示胆总管扩张程度、部位及梗阻端形态,对诊断及鉴别诊断有重要价值。     

Cytoskeletal changes in rat cortical neurons induced by long-term intraventricular infusion of leupeptin

Neurofibrillary tangles (NFTs), which are composed of paired helical filament (PHF)-like filaments, were induced by the long-term intraventricular infusion of leupeptin, a potent protease inhibitor. The fibrils composing the NFTs were 20 nm in maximal width and had periodic constrictions at 40-nm intervals. They were identical to the PHF that had been found in aged rat neurons. Dystrophic axons filled with mainly tubular structures were also abundantly found in the parietal and temporal isocortices, which were not affected in the acute or subacute phases of leupeptin treatment. An immunohistochemical study using antibodies related to the neuronal cytoskeleton showed that neuronal cytoskeletal changes accompanying ubiquitination occurred in dystrophic axons distributed widely in the isocortex as well as the hippocampal formation. The present findings suggest that long-term administration of leupeptin accelerates the neuronal ageing process in rats and causes other neuronal changes: NFT formation, such as seen in the aged brain or in neurodegenerative diseases including Alzheimer's disease, in addition to accumulation of lipofuscin granules and degeneration of neuronal processes. In other words, some disturbance of the balance between proteases and their inhibitors may play an important role in the neuronal ageing process, and some regulatory intervention in the intraneuronal protease activity may provide a new therapeutic strategy for the neurodegenerative diseases.This study was presented in part at the Third International Congress on Alzheimer's Disease and Related Disorders at Padova in July 1992     

Ubiquitin immunoreactivity of paired helical filaments differs in Alzheimer’s disease and corticobasal degeneration

To establish whether there is a relationship between ubiquitination and ultrastructural appearance of filaments, we compared the ubiquitin immunoreactivity of paired helical filaments (PHFs) in Alzheimer’s disease (AD) and corticobasal degeneration (CBD). PHFs in these disorders share a limited similarity since filaments in CBD are wider and twisted at longer intervals than those in AD, and also display less ultrastructural stability. Preparations enriched in SDS-soluble filaments were isolated from AD and CBD brains and subjected to tau and ubiquitin immunogold labeling. Both preparations contained mostly dispersed individual PHFs, which labeled for the amino and carboxyl termini of tau. Immunolabeling of ubiquitin was variable, however, being more intense in AD than CBD samples. SDS-insoluble filaments were prepared from PHFs by boiling in the presence of SDS and 2-mercaptoethanol and collected by sedimentation. In both disorders, the pellets contained highly aggregated and bundled filaments, which were devoid of the amino but not the carboxyl terminal region of tau. Again, ubiquitin labeling was more intense in AD than CBD filaments. The present results suggest that ubiquitination has limited influence on SDS solubility, aggregation and bundling of PHFs; however, it may be one of the factors responsible for the ultrastructural variability and/or stability of filaments. Received: 6 March 1998 / Revised, accepted: 14 May 1998     

Coexistence of paired helical filaments and polyglucosan bodies in the same neuron in an autopsy case of Alzheimer’s disease

The coexistence of polyglucosan bodies (PBs) and paired helical filaments (PHFs) in the same neuron is reported in an autopsy case of Alzheimer’s disease. The patient was a 56-year-old Japanese male with a typical clinical course and pathological findings of Alzheimer’s disease. Electron microscopically, numerous neurofibrillary tangles, mainly composed of PHFs, were observed in the neuronal cytoplasm, axons and dendrites. Some of them coexisted with other filamentous structures, which comprised randomly oriented branching filaments with a diameter of 5–10 nm. These structures were compatible with PBs. Glial tangles could not be found. Coexistence of these two structures was thought to occur in neurites. Received: 16 October 1995 / Revised, accepted: 20 May 1996