重离子12C对60Coγ射线诱发人染色体畸变效应的比较研究

目的 重离子和高剂量率^60Coγ射线照射离体人血建立染色体畸变的剂量-效应曲线；比较重离子^12C照射与^60Coγ射线照射诱发染色体畸变的相对生物效能。方法 重离子^12和^60Coγ射线照射离体人血，吸收剂量率为3Gy/min，吸收剂量为1．0～8．0Gy。主要记录染色体型畸变的非稳定性畸变，对双着丝粒体和着丝粒环做曲线拟合，并检验回归系数的显著性和曲线的拟合度。结果 重离子^12C和^60Coγ射线照射离体血诱发的染色体畸变(双 环)，在0—8Gy范围内，呈良好的剂量一效应关系。^12C离子诱发染色体畸变的RBE值是不恒定的，它随吸收剂量增加而减少，在0．3—8．0Gy范围内，RBE值(Dr/Dc)从2．62到1．00，平均1．58。结论 ^12C离子对^60Coγ射线照射诱发染色体畸变，在照射剂量较低时，有较高的生物效应。     

AT细胞系辐射敏感性与细胞凋亡的相关研究

目的 探讨AT细胞高辐射敏感性与细胞凋亡之间的联系。方法 以液体闪烁测量法测3H-TdR掺入百分率来观察^60Co γ射线照射对AT5BIVA（AT）和GM0639（GM）细胞增殖的影响;实验于照射后0、24、48和72 h,用细胞流式术动态检测AT和GM细胞的自发凋亡率及^60Co γ射线照射诱发的凋亡率。结果 ^60Co γ射线0～6 Gy照射后,AT和GM两种细胞3H-TdR掺入百分率均呈剂量依赖性降低,且AT细胞降低得比GM细胞快,两种细胞3H-TdR掺入百分率与受照射剂量间可拟合成指数方程：SAT=0.9718e^-0.6855D（R^2=0.9950）、SGM=1.0928e^-0.3731D（R^2=0.9777）;AT细胞的自发凋亡率高于GM细胞;2～6 Gy照后24 h,两种细胞由辐射诱发的凋亡率均随照射剂量增大而升高,且在同一剂量点,前者凋亡率高于后者;2 Gy照射后0～72 h,AT和GM细胞的凋亡率均呈时间依赖性增加,且随照后时间延长两者间差异逐步增大,在72 h达到显著水平。结论 AT细胞高辐射敏感性与其较高的自发及辐射诱发的凋亡密切相关。     

β和γ射线照射肿瘤细胞的生物效应比较

目的 比较低剂量率β射线和高剂量率γ射线照射诱发肿瘤细胞生物效应特点。方法采用^32Pβ射线和^60Coγ射线照射人宫颈癌HeLa细胞系，用台盼蓝排除法和X-gal衰老细胞染色法比较两种照射肿瘤细胞死亡方式的差异。结果 ^32Pβ射线(0．375cGy/min)和^60Coγ射线(206cGy/min)照射HeLa细胞后72h的结果表明，低剂量率β射线抑制细胞增殖为渐进性，使多数的细胞在一个或几个细胞倍增周期后死亡，以增殖性死亡为主；高剂量率γ射线对细胞的抑制作用直接、迅速，细胞坏死比例高，增殖性死亡(衰老)比例低于持续低剂量照射方式。结论 不同的辐射方式对细胞的杀伤方式不同，了解其放射生物学机理有助于临床治疗方案的选择。     

酵母TEL1基因对辐射诱发A-T细胞染色体畸变的影响

目的研究酵母TEL1基因在毛细血管扩张-运动共济失调症(ataxia-telangiectasia,A-T)A-T细胞中的异位表达对辐射诱发A-T细胞染色体畸变的影响.方法稳定转染酵母TEL1全基因序列、酵母TEL1基因片断和pRep5空载体的AT-TEL1、AT-deltaTEL1、AT-rep、GM-rep细胞分别在含100μg/ml潮霉素的DMEM培养液中培养;A-T细胞和正常对照的GM639细胞分别在DMEM培养液中常规培养.应用60Co源对处于指数生长期的上述细胞进行γ射线照射,吸收剂量分别为0,1和3Gv.应用常规染色体技术制片,并进行染色体畸变分析.结果传代培养的AT-TEL1、AT-deltaTEL1、AT-rep、A-T、GM639、GM-rep细胞的染色体数目均是非整倍体;无论是A-T细胞染色体自发畸变率还是辐射诱发的染色体畸变率均明显高于正常对照的GM639纤维母细胞;A-T细胞的高染色体畸变率主要是由于染色体双着丝粒体和染色体断片所至的染色体型畸变;稳定转染酵母TEL1全基因序列的AT-TEL1细胞染色体自发畸变率与A-T细胞之间差异无显著性(P＞0.05);辐射诱发AT-TEL1细胞的染色体畸变率明显低于A-T细胞(P＜0.01);辐射诱发AT-deltaTEL1、AT-rep细胞染色体畸变率则高于A-T细胞.结论酵母TEL1基因在A-T细胞中的异位表达,能够明显降低电离辐射诱发的A-T细胞染色体畸变率.     

M-FISH技术检测辐射诱导染色体易位和双着丝粒畸变

目的　探讨用多色荧光原位杂交 (M FISH)技术检测的易位和双着丝粒染色体畸变的差异。方法　用 1,2 ,3,7,8,9,14和 15号染色体端粒和着丝粒特异性探针的M FISH方法 ,分析6 0 Coγ射线离体照射的脐带血淋巴细胞染色体易位和双着丝粒畸变。结果　 (1)用M FISH方法分析6 0 Coγ射线诱导的易位和双着丝粒染色体畸变的剂量 效应曲线 ,均符合线性二次剂量效应模式 ;易位与双着丝粒的比值在大多数剂量水平不等于 1。 (2 )细胞中无非稳定性畸变的完全相互易位的比例随着吸收剂量的增加而降低。 (3)对大多数被标记染色体 ,3 0 0Gyγ射线照射诱发的染色体畸变观察值与理论值无差别 ;9号染色体畸变 (易位和双着丝粒 )观察值显著高于理论值 (P <0 0 5或P <0 0 1) ,15号染色体易位观察值显著低于理论值 (P <0 0 1)。结论　电离辐射诱导的染色体易位率不等于双着丝粒畸变率 ;对于大多数染色体 ,辐射诱发染色体易位率和双着丝粒畸变率符合随机性规律。     

ATM基因对60Co γ射线照射后AT细胞hTERT表达的影响

目的研究外源性ATM基因对电离辐射照射的毛细血管扩张-共济失调症（ataxia tehngiectasia，AT）患者皮肤的成纤维细胞系AT细胞（AT5BIVA）hTERT mRNA和蛋白表达的影响。方法以正常人皮肤的成纤维细胞系GM细胞（GM0639）为对照，应用RT-PCR与Western blot实验方法，观察经0、1、3和5Gy（剂量率1．0Gy／min）^60Coγ射线照射后，AT细胞、空载体AT细胞、ATM^＋-AT细胞和GM细胞的hTERT mRNA和蛋白表达的变化。结果未照射时，除GM细胞外，其余各细胞均有hTERT mRNA和蛋白的表达；ATM^＋-AT细胞的hTERT mRNA和蛋白表达量较AT细胞明显下降（P〈0．05）；ATM^＋-AT细胞的hTERT mRNA和蛋白表达量仍然明显高于GM细胞的hTERT mRNA表达量。在1～5Gy剂量范围内，AT、空载体AT、ATM^＋-AT和GM细胞的hTERT mRNA和蛋白表达量呈剂量依赖性增加；在相同照射剂量点，ATM^＋-AT细胞的hTERT mRNA表达量较AT细胞均有明显降低（P〈0．05）。结论电离辐射可诱导细胞hTERT mRNA和蛋白的表达；并且细胞hTERT mRNA和蛋白表达量呈剂量依赖性增加；外源性ATM基因可下调AT细胞hTERT mRNA和蛋白的表达。推测端粒酶参与电离辐射诱导DNA损伤的修复。     

60Coγ射线照射诱导人卵巢癌细胞凋亡及细胞周期的改变

目的：探讨^60Coγ射线照射对人卵巢癌细胞株A2780及其顺铂耐药株A2780－CP体外生长、凋亡及细胞周期的影响。方法：采用四甲基偶唑蓝（MTT）比色法分析不同辐照剂量（1－10Gy)对A2780及A2780－CP两种细胞株体外生长的影响,用流式细胞术（FCM）比较两者辐照后凋亡及细胞周期的变化。结果：（1）1－10^60Coγ射线照射引起A2780细胞株明显的生长抑制和凋亡,而A2780－CP细胞则表现出明显的辐照抗性。（2）6Gy ^60Coγ射线照射后6－48hA1780细胞呈现G1期细胞阻滞和S期细胞比较下降,A2780－CP细胞则呈G1期细胞比例减少和S期细胞比例增加。结论卵癌耐药细胞具有辐射抗性和物征性的细胞周期变化,流式细胞术测定辐照诱导肿瘤细胞凋讯及细胞周期的变化可预测恶性肿瘤细胞的辐射敏性。     

G_1期人淋巴细胞的细胞遗传学与存活适应性反应

用T细胞克隆法分析了用低剂量和高剂量X射线照射PHA刺激后处于第1个G_1期人淋巴细胞的染色体畸变和细胞致死效应,以检验D_1期细胞遗传学适应性反应是否能导致存活适应性反应.血样来自6名献血员,分离并培养单核细胞层,加PHA 12和18小时后,分别以5cGy(20cGy/min)和200cGy或400cGy(1Gy/min)X射线照射培养物.观察细胞存活和染色体畸变情况.对5人的细胞遗传学分析表明,在5cGy+400cGy组均存在适应性反应,其中3人双着丝粒及环以及2人的缺失显著减少;在5cGy+200cGy组,     

低剂量辐射刺激作用的实验研究

本文报告低剂量,低LET辐射对小鼠免疫功能、染色体畸变和DNA损伤修复影响的实验资料。低剂量单次x线或持续γ线全身照射后,出现辐射刺激效应,表现为(1)增强免疫功能,包括抗体形成反应增强、自介素2产生增多、NK活性增高、胸膜细胞增殖加快和ConA诱导的大分子合成激活,(2)诱导细胞遗传学适应性反应,即低剂量辐射预先作用使相继较大剂量所致染色体损伤减轻； (3)促进DNA修复,包括非程序DNA合成增强和DNA聚合酶活性增高。对辐射刺激效应的发生机理和意义进行了讨论。     

γ射线诱发染色体畸变的原子力显微镜观察

目的 为寻找辐射损伤新的检测方法，用原子力显微镜观察正常及^60Coγ射线照射后的染色体结构改变。方法 制备正常及受照射人外周血淋巴细胞染色体标本，用原子力显微镜观测染色体的三维结构及其高度变化。结果 正常染色体三维结构及受照射染色体中双着丝粒体结构清晰可见，提供的染色体高度数据利于双着丝粒体的识别。结论 原子力显微镜通过高分辨三维成像及线性测量为辐射诱发染色体畸变分析提供了一种新的有价值的检测方法。     

Knee injury and Osteoarthritis Outcome Score (KOOS) - validation of a Swedish version

The Knee injury and Osteoarthritis Outcome Score (KOOS) is a self-administered instrument measuring outcome after knee injury at impairment, disability, and handicap level in five subscales. Reliability, validity, and responsiveness of a Swedish version was assessed in 142 patients who underwent arthroscopy because of injury to the menisci, anterior cruciate ligament, or cartilage of the knee. The clinimetric properties were found to be good and comparable to the American version of the KOOS. Comparison to the Short Form-36 and the Lysholm knee scoring scale revealed expected correlations and construct validity. Item by item, symptoms and functional limitations were compared between diagnostic groups. High responsiveness was found three months after arthroscopic partial meniscectomy for all subscales but Activities of Daily Living.     

The acutely limping child

Acute limping may be the result of multiple pathologies in children. The differential diagnosis varies based on the age of the child. Irrespective of age, the initial imaging work-up includes AP and frog leg radiographs of the pelvis and ultrasound; MRI may sometimes be helpful. In children less than 3 years, infections and trauma are most frequent. MRI is the imaging modality of choice when osteomyelitis is clinically suspected. Between the ages of 3 and 10 years, transient synovitis of the hip and Legg-Calvé-Perthes disease are main considerations but infection, inflammation and focal bony lesions are also considered. In children over 10 years, slipped capital femoral epiphysis also is considered.     

Do Balance Board Training Programs Reduce the Risk of Ankle Sprains in Athletes?

Introduction Ankle sprains are the most common musculo-skeletal injury that occurs in athletes,particularly in sports that require jumping and landing on one foot such as soccer,and basketball(1-4).These injuries often result in significant time loss from participation,long-term disability,and have a major impact on health care costs and resources(5-8).     

High Intensity Interval Training:New Insights

KEY POINTS ·High-intensity interval training(HIT)is characterized by repeated sessions of relatively brief，intermittent exercise.often performed with an“a11 out”effort or at an intensity close to that which elicits peak oxygen uptake(i.e.，≥90%of VO2 peak).     

Endovascular management of carotid-cavernous fistulas

Objective To investigate endovascular treatment of traumatic direct carotid-cavernous fistulas （CCF） and their complications such as pseudoaneurysms. Methods： Over a five-year period, 22 patients with traumatic direct CCFs were treated endovascularly in our institution. Thirteen patients were treated once with the result of CCF occluded, 8 twice and 1 three times. Treatment modalities included balloon occlusion of the CCF, sacrifice of the ipsilateral internal carotid artery with detachable balloon, coll embolization of the cavernous sinus and secondary pseudoaneurysms, and covered-stem management of the pseudoaneurysms. Results All the direct CCFs were successfully managed endovascularly. Four patients developed a pseudoaneurysm after the occlusion of the CCF with an incidence of pseudoaneurysm formation of 18.2% （4/22）. A total number of 8 patients experienced permanent occlusion of the ICA with a rate of ICA occlusion reaching 36.4% （8/22）. Followed up through telephone consultation from 6 months to 5 years, all did well with no recurrence of CCF symptoms and signs. Conclusion Traumatic direct CCFs can be successfully managed with endovascular means. The pseudoaneurysms secondary to the occlusion of the CCFs can be occluded with stent-assisted coiling and implantation of covered stents.     

Developmental validation of the PowerPlex(®) ESI 16 and PowerPlex(®) ESI 17 Systems: STR multiplexes for the new European standard

In response to the ENFSI and EDNAP groups’ call for new STR multiplexes for Europe, Promega^® developed a suite of four new DNA profiling kits. This paper describes the developmental validation study performed on the PowerPlex^® ESI 16 (European Standard Investigator 16) and the PowerPlex^® ESI 17 Systems. The PowerPlex^® ESI 16 System combines the 11 loci compatible with the UK National DNA Database^®, contained within the AmpFlSTR^® SGM Plus^® PCR Amplification Kit, with five additional loci: D2S441, D10S1248, D22S1045, D1S1656 and D12S391. The multiplex was designed to reduce the amplicon size of the loci found in the AmpFlSTR^® SGM Plus^® kit. This design facilitates increased robustness and amplification success for the loci used in the national DNA databases created in many countries, when analyzing degraded DNA samples. The PowerPlex^® ESI 17 System amplifies the same loci as the PowerPlex^® ESI 16 System, but with the addition of a primer pair for the SE33 locus. Tests were designed to address the developmental validation guidelines issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM), and those of the DNA Advisory Board (DAB). Samples processed include DNA mixtures, PCR reactions spiked with inhibitors, a sensitivity series, and 306 United Kingdom donor samples to determine concordance with data generated with the AmpFlSTR^® SGM Plus^® kit. Allele frequencies from 242 white Caucasian samples collected in the United Kingdom are also presented. The PowerPlex^® ESI 16 and ESI 17 Systems are robust and sensitive tools, suitable for the analysis of forensic DNA samples. Full profiles were routinely observed with 62.5 pg of a fully heterozygous single source DNA template. This high level of sensitivity was found to impact on mixture analyses, where 54–86% of unique minor contributor alleles were routinely observed in a 1:19 mixture ratio. Improved sensitivity combined with the robustness afforded by smaller amplicons has substantially improved the quantity of data obtained from degraded samples, and the improved chemistry confers exceptional tolerance to high levels of laboratory prepared inhibitors.     

Bronchial stump fistula :treatment with covered retrievable hinged metallic stents-preliminary clinical experience

Objective To evaluate the preliminaily clinical efficacy and retrievability of a retrievable hinged covered metallic stent in the treatment of the bronchial stump fistula （BSF）. Methods Between April 2003 and March 2005, 8 patients with bronchial stump fistula after pneumonectomy or lobectomy were treated with two types （A and B） of retrievable hinged covered metallic stents. Type A stent was placed in 6 patients and type B in 2 under fluoroscopic guidance. The stent was removed with a retrieval set when BSF was healed or complications occurred. Results Stent placement in the bronchial tree was technically successful in all patients, without procedure-related complications. Immediate closure of the BSF was achieved in all patients after the procedure. Stents were removed from all patients but one. Removal of the stents was difficult in two patients due to tissue hyperplasia. Patients were followed up for 6 - 21 months. Placement of the stents remained stable in all patients except one due to severe cough. Permanent closure of BSF was achieved in 7 （87.5%） of 8 patients. Conclusion Use of a retrievable hinged covered expandable metallic stent is a simple, safe, and effective procedure for closure of the BSF. Retrieval of the stent seems to be feasible. （J Intervent Radiol, 2007, 16： 253-257）     

Prevalence and severity of hip and groin pain in sub‐elite male football: a cross‐sectional cohort study of 695 players

The purpose of this study was twofold: (a) to investigate the prevalence of hip and groin pain in sub‐elite male adult football in Denmark and (b) to explore the association between prevalence and duration of hip and groin pain in the previous season with the Copenhagen Hip and Groin Outcome Score (HAGOS) in the beginning of the new season. In total 695 respondents from 40 teams (Division 1–4) were included. Players completed in the beginning of the new season (July–Sept 2011) a self‐reported paper questionnaire on hip and/or groin pain during the previous season and HAGOS. In total 49% (95% CI: 45–52%) reported hip and/or groin pain during the previous season. Of these, 31% (95% CI: 26–36%) reported pain for >6 weeks. Players with the longest duration of pain during the previous season had the lowest HAGOS scores, when assessed at the beginning of the new season, P < 0.001. This study documents that half of sub‐elite male adult football players report pain in the hip and/or groin during a football season. The football players with the longest duration of pain in previous season displayed the lowest HAGOS scores in the beginning of the new season.