An Evidence-Based Review of Total Body Irradiation

The purpose of this literature review is to investigate clinical treatment methods of total body irradiation within the context of a clinical department adopting a paediatric cohort with no existing technique. An extensive review of the literature was conducted using PubMed, Science Direct, Google Scholar, and Clinicians Knowledge Network. Articles were limited to nonhelical tomotherapy, nonparticle therapies, and those using hyperfractionated regimes. Total marrow irradiation was excluded because of national treatment and trial limitations. Of the numerous patient positioning methods present within the literature, the most comfortable and reproducible positioning methods for total body irradiation include both supine and the supine and/or prone combination. These positions increased stability and patient comfort during treatment, while also facilitating computed tomography data acquisition at the simulation stage. Ideally, dose calculations should be performed using a three-dimensional treatment planning system and quality assurance procedures that include in vivo dosimetry measurements. The available literature also suggests inhomogeneity correction factors and intensity modulation are superior to conventional open field techniques and should be implemented within developing protocols. Dynamic machine dose modulation is suggested to reduce department impact, removing the need for tissue compensators and accessory shielding devices, while providing significant improvements to treatment time and dose accuracy. Further long-term survival and intensity modulation studies are warranted, including direct comparisons of both dose modulation and treatment efficiency.     

电子线照射对小鼠胰岛素生长因子相关蛋白表达的影响

目的：探讨电子线对胰岛素生长因子-1家族蛋白表达的影响，为研究辐射对肝脏的早期损伤提供依据。方法：采用电子线照射小鼠，照射剂量为1、2、4 Gy，用Western blot法检测照射后12、48和72 h小鼠肝脏中胰岛素生长因子1受体（IGF-1R）、胰岛素生长因子结合蛋白1（IGFBP1）、胰岛素生长因子结合蛋白4（IGFBP4）和胰岛素生长因子1（IGF-1）蛋白表达水平的改变。结果：照射剂量为1 Gy时，与对照组相比，IGF-1蛋白在照射后48 h时表达增加，IGFBP1、IGFBP4和IGF1R蛋白的表达在照射后12、48和72 h均表达减少。照射剂量为2 Gy时，IGF-1和IGFBP4蛋白在照射后48 h时表达增加，其余时间点表达减少。IGFBP1蛋白在照射后12 h时表达增加，48和72 h时表达减少。IGF1R蛋白在照射后3个时间点均呈现为表达减少。照射剂量4 Gy时，肝脏中IGF-1、IGFBP1和IGFBP4蛋白均表达减少，IGF1R蛋白在照射后12 h时表达增加，48、72 h时均表达减少（均为P < 0.05）。结论：电子线照射后小鼠肝脏中胰岛素生长因子-1家族蛋白多以下调表达为主，与前期基因表达的结果相一致，有可能作为反映放射性工作人员早期肝脏损伤的生物标志物之一。     

Ultrastructural detection of neuronally transported choleragenoid by postembedding immunocytochemistry in freeze-substituted Lowicryl HM20™ embedded tissue

Choleragenoid (cholera toxin B-fragment; CTB) is an anterograde, retrograde and transganglionic neuronal tracer. We describe a method for detecting CTB-labeled neuronal cell bodies, neurites and boutons at the ultrastructural level, using postembedding immunogold techniques on freeze-substituted Lowicryl HM20™ embedded nervous tissue. Primary afferents and motoneurons were labeled by injection of CTB in the dorsal ramus of the C2 spinal nerve of the rat. Following fixation with paraformaldehyde (4%) and glutaraldehyde (0.25%), tissue sections from the spinal cord C2 segment were freeze-substituted and embedded in Lowicryl HM20™ and subsequently processed with postembedding immunocytochemistry for CTB and glutamate. Immunogold particles indicating CTB immunoreactivity were found over primary afferents and motoneurons. In primary afferents in the central cervical nucleus (CCN) and motor nuclei, immunogold labeling was seen in boutons over vesicle-containing axoplasm and to a lesser extent over axoplasm devoid of vesicles, but not over mitochondria or axolemma. In motoneurons, immunogold particles were seen over the Golgi apparatus in the soma and over lysosomes in both soma and dendrites. Quantification of glutamate-like immunoreactivity in 20 CTB-labeled and 20 CTB-negative boutons in the neuropil was found similar, indicating that CTB does not interfere with the immunocytochemical detection of neuronal epitopes such as the transmitter substance glutamate.     

小儿特发性血小板减少性紫癜发病机制的研究

本文采用体外建立抗原—抗体—补体反应体系的试验方法,通过测定该反应体系的血小板~(51)Cr 释放量来进一步探讨特发性血小板减少紫癜(ITP)患儿血小板的破坏机制。结果45例ITP 惠儿其血小板~(51)Cr 释放量与正常值比较明显增高(P<0.01),急慢性之问无显著差异性。45例患儿中有31例血小板~(51)Cr释放量高出正常值上限。同时观察ITP 患儿血清对血小板超微形态和结构的影响,发现血小板表面有圆钝伪足形成,血小板聚集,血小板脱颗粒和空泡性变。正常儿血清对血小板超微形态和结构无明显影响。作者认为,ITP 患儿的血小板相关抗体,能介导血管内血小板的溶解与破坏,其既影响血小板数量,又改变血小板的结构,二者都是导致该病出血的重要原因。     

电镜下的乙型肝炎表面抗原

本文对81例乙型肝炎病人的肝活检组织进行了电镜观察,发现HBsAg的阳性率达93.8％。电镜下,HBsAg细丝不仅有一般的管状细丝型,还有分枝管型和管泡型,而且CAH病人肝组织不易找到HBsAg丝(易见者仅9％),CPH,CLH则多数(79.5％)为易见及可见,二者有高度显著性差异(P<0.01)。     

小剂量低LET辐射对人淋巴细胞SCE的影响

本文用磷酸盐Giemsa法观察了小剂量X射线照射对人离体外周血淋巴细胞SCE的影响。其结果照射组各剂量点均不明显地高于对照组,证实了SCE对电离辐射不敏感,说明染色体结构畸变和SCE的发生是彼此独立的两个不同事件。     

电子直线加速器照射对NIH 3T3细胞的细胞周期及凋亡的影响

目的 探讨电子直线加速器照射对细胞周期及细胞凋亡的影响。方法 采用直线加速器对NIH 3T3细胞进行照射，观察细胞周期及细胞凋亡的改变情况；同时测定损伤前后p53蛋白的表达情况。结果 照射后细胞凋亡数增加，p53蛋白表达量上升。结论 电子直线加速器照射损伤可诱导细胞凋亡。     

紫外线照射后哺乳动物细胞DNA的期外合成

本实验用~3H-TdR掺入,液体闪烁测量法测定细胞DNA期外合成的方法,测定了小鼠和大鼠的肠淋巴结细胞、人和大鼠外周血淋巴细胞、S-180V肿瘤细胞等经紫外线照射后的UDS,观察到UDS掺入量随辐照度增加而增加。在同一辐照剂量下,以小鼠肠淋巴结细胞的UDS值最高,其次是人外周血淋巴细胞和S-180V肿瘤细胞,而大鼠外周血淋巴细胞和肠淋巴结细胞最低。     

Scanning Electron Microscopic Observations on the Epithelium of the Human Prostatic Urethra

The human prostatic urethra has been investigated by means of scanning electron microscopy. On the posterior wall of the urethra, the seminal colliculus with the orifices of the ejaculatory ducts is clearly detectable. The upper portion of the prostatic urethra shows a typical transitional epithelium with large superficial cells of a ruffled appearance. In the lower portion of the organ (underneath the openings of the ejaculatory ducts), the apical pattern of the cells varies considerably. Four main aspects are recognizable: apices provided with microvilli, dome-shaped apices with an almost smooth surface, large apices with labyrinthic microplicae and ciliated apices. Also, apices showing intermediate characteristics can be noted. The functional significance of the morphological patterns as well as the possibility of a transition among the various types of surface structures are discussed.