Does an additional antirotation U-Blade (RC) lag screw improve treatment of AO/OTA 31 A1-3 fractures with gamma 3 nail?

IntroductionPoor bone quality and unstable fractures increase the cut-out rate in implants with gliding lag screws. The U-Blade (RC) lag screw for the Gamma3^® nail was introduced to provide monoaxial rotational stability of the femoral head and neck fragment. The purpose of this study was to evaluate whether the use of the U-Blade (RC) lag screw is associated with reduced cut-out in patients with OTA/AO 31A1-3 fractures.Material & methodsBetween 2009 and 2014, 751 patients with OTA/AO 31A1-3 fractures were treated with a Gamma3^® nail at our institution. Out of this sample 199 patients were treated with U-blade (RC) lag screws. A total of 135 patients (117 female, 18 male) with standard lag screw (treatment group A) were matched equally regarding age (±4 years) sex, fracture type and location to 135 patients with U-blade (RC) lag screw (treatment group B). Within a mean follow up of 9.2 months (range 6–18 months) we assessed the cut-out rate, the calTAD, lag screw migration, the Parker's mobility score and the Parker’s ratio at postoperatively, six and 12 months following surgery. Furthermore we recorded all complications, ASA-Score, hospital stay and duration of surgery retrospectively.ResultsThe most common fracture among group B with a cut-out of the lag screw were AO/OTA 2.3 and 3.2 fractures whereas in group A cut-out was most commonly seen in AO/OTA 2.1, 2.2 and 2.3 fractures, there was no significant reduction of the cut-out rate in group B 2.2% (n = 3) compared to group A 3.7% (n = 5). The duration of surgery was significantly shorter in group A (p < 0.05). There was no significant difference in lag screw placement, the Parker’s ratio and mobilization.ConclusionIn our study the U-Blade (RC) lag screw did not reduce the cut-out in treatment of OTA/AO 31A1-3 fractures at all. Considering the longer duration of surgery and the higher costs of the U-Blade (RC) lag screw, our results do not justify its use. However, further prospective randomized studies will be necessary.     

Pulse mode of laser photodynamic treatment induced cell apoptosis

One of the factors limiting photodynamic therapy (PDT) is hypoxia in tumor cells during photodynamic action. PDT with pulse mode irradiation and appropriate irradiation parameters could be more effective in the singlet oxygen generation and tissue re-oxygenation than continuous wave (CW) mode. We theoretically demonstrate differences between the cumulative singlet oxygen concentration in PDT using pulse mode and CW mode of laser irradiation. In vitro experimental results show that photodynamic treatment with pulse mode irradiation has similar cytotoxicity to CW mode and induces mainly cell apoptosis, whereas CW mode induces necrotic cell death. We assume that the cumulative singlet oxygen concentration and the temporal distribution of singlet oxygen are important in photodynamic cytotoxicity and apoptosis initiation. We expect our research may improve irradiation protocols and photodynamic therapy efficiency.     

Thiotepa‐based versus total body irradiation‐based myeloablative conditioning prior to allogeneic stem cell transplantation for acute myeloid leukaemia in first complete remission: a retrospective analysis from the Acute Leukemia Working Party of the European Group for Blood and Marrow Transplantation

Thiotepa is an alkylating compound with an antineoplastic and myeloablative activity and can mimic the effect of radiation. However, it is unknown whether this new regimen could safely replace the long‐established ones. This retrospective matched‐pair analysis evaluated the outcome of adults with acute myeloid leukaemia in first complete remission who received myeloablative conditioning either with a thiotepa‐based (n = 121) or a cyclophosphamide/total body irradiation‐based (TBI; n = 358) regimen for allogeneic hematopoietic stem cell transplantation from an HLA‐matched sibling or an unrelated donor. With a median follow‐up of 44 months, the outcome was similar in both groups. Acute graft‐versus‐host disease grade II‐IV was observed in 25% after thiotepa‐containing regimen versus 35% after TBI (P = 0.06). The 2‐yr cumulative incidence of chronic graft‐versus‐host disease was 40.5% for thiotepa and 41% for TBI (P = 0.98). At 2 yrs, the cumulative incidences of non‐relapse mortality and relapse incidence were 23.9% (thiotepa) vs. 22.4% (TBI; P = 0.66) and 17.2% (thiotepa) vs. 23.3% (TBI; P = 0.77), respectively. The probabilities of leukaemia‐free and overall survival at 2 yrs were not significantly different between the thiotepa and TBI groups, at 58.9% vs. 54.2% (P = 0.95) and 61.4% vs. 58% (P = 0.72), respectively. Myeloablative regimens using combinations including thiotepa can provide satisfactory outcomes, but the optimal conditioning remains unclear for the individual patient in this setting.     

CT引导下脉冲射频联合神经阻滞治疗带状疱疹后神经痛的疗效影响因素分析

目的 探讨CT引导下脉冲射频联合神经阻滞治疗带状疱疹后神经痛（PHN）疗效的影响因素。 方法 对102例接受CT引导下脉冲射频联合神经阻滞治疗的PHN患者进行回顾性分析,统计患者的简化McGill疼痛问卷（SF-MPQ）总分和疼痛视觉模拟评分法（VAS）评分。根据治疗后6个月的SF-MPQ总分及随访情况,将患者分为疗效良好组（44例）和疗效不佳组（58例）。采用Logistic单因素和多因素回归法分析影响疗效的独立相关因素。 结果 2组患者治疗后1周、1个月、3个月、6个月的疼痛VAS评分均较组内治疗前下降（P＜0.05）,且疗效良好组各时间点的疼痛VAS评分均较疗效不佳组低（P＜0.05）。多因素Logistic回归分析显示,年龄>60岁［β=0.972,95%CI（1.084,6.448）,P=0.033］、病程>6个月［β=1.211,95%CI（1.243,9.068）,P=0.017］、治疗前疼痛VAS评分7~10分［β=1.029,95%CI（1.642,4.769）,P<0.001］均是影响疗效的独立危险因素（P＜0.05）。采用利多卡因作为神经阻滞药物［β=-0.792,95%CI（0.235,0.873）,P=0.019］、持续使用镇痛药物时间>2周［β=-1.047,95%CI（0.164,0.749）,P=0.007］是疗效的保护性因素（P＜0.05）。 结论 CT引导下脉冲射频联合神经阻滞可有效缓解PHN,其疗效与患者的年龄、病程、治疗前VAS评分、治疗时采用的神经阻滞药物种类、持续使用镇痛药物的时间有关。     

加速器机架旋转加速度约束条件对VMAT计划的影响研究

目的:研究直线加速器机架旋转加速度设置,对多病种容积旋转调强(VMAT)计划剂量学、机器效率和计划验证结果的影响,探讨机器模型中机架加速度约束条件的优化选择。方法:分别选取10例鼻咽癌、非小细胞肺癌、乙状结肠腺癌腹膜后淋巴结转移和乳腺浸润性导管癌病例,在Pinnacle v9.10计划系统中建立允许机架旋转加速度变化和...     

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。     

部分照射离体血对淋巴细胞染色体畸变形成的影响

目的 分析⁶⁰Coγ射线部分照射离体血对人外周血淋巴细胞染色体畸变形成的影响。方法 用2Gy⁶⁰Coγ射线37℃照射人外周血后以不同比例混合后进行培养、制片和分析染色体畸变。结果 染色体畸变随照射血比例的增加而增加,与单纯照射组相比,混合照射血的染色体畸变率高。1:1比例混合估算出的剂量为1.27Gy,大于1Gy;0.5:1比例混合估算出的剂量为0.93Gy,大于0.5Gy;而在1:0组,照射剂量与估算剂量基本一致。结论 染色体畸变可以作为估算非均匀照射的生物学指标之一。     

非小细胞肺癌脑转移瘤治疗方案的优化选择

目的优化选择非小细胞肺癌脑转移瘤的治疗方案。方法72例均有病理学诊断的住院患者。随机分成3组。全颅外放疗组24例(Ⅰ组)。伽玛刀加全颅放疗组22例(Ⅱ组)。伽玛刀加全颅放疗联合Vm-26治疗组26例(Ⅲ组)。全脑外放疗中心剂量36~41Gy,常规分割4~5周完成。伽玛刀治疗以50%等中心剂量曲线严格覆盖肿瘤边缘,处方剂量16~25Gy,平均16Gy。化疗:于全颅放疗DT19-29Gy,2~3周后,加Vm-26化疗,60mg·m2·d-1,连用3d,21d为1周期,共用2个周期。化疗期间继续放疗。结果Ⅰ、Ⅱ和Ⅲ组的中位生存时间分别为6·0(1·2~19·0)、9·2(4·4~30·0)和10·8(5·2~42·2)个月,1、2年生存率分别为34·6%和12·6%;62·2%和30·2%;70·8%和35·6%。结论采用3种不同方法治疗非小细胞肺癌脑转移瘤,Ⅲ组在提高局部控制率、延长生存期上明显优于Ⅰ组和Ⅱ组,且毒副作用可耐受。     

超声联合微泡抑制血管平滑肌细胞增殖机制的研究

目的观察超声联合微泡对血管平滑肌细胞(VSMCs)周期分布及细胞周期调节蛋白激酶(CDK2)和抑制物p27表达的影响,探讨超声联合微泡抑制VSMCs增殖的作用机制。方法体外培养的VSMCs经血小板衍生生长因子-BB(PDGF-BB)刺激后,以低频连续波超声(频率1MHz、声强为0.3W/cm2)联合脂质微泡(1μl/ml)辐照VSMCs60s。分别用流式细胞仪、免疫细胞化学法检测细胞周期分布和细胞周期调控蛋白CDK2、p27的表达。结果与对照组比较,PDGF-BB刺激组细胞G0～G1期细胞比例下降而S期细胞比例增高(P<0.01),CDK2表达上调而p27表达降低(P<0.01);与PDGF-BB组相比,超声联合微泡组G0～G1期细胞比例增高,S期细胞比例降低(P<0.01),CDK2表达下调而p27表达增高(P<0.01)。结论超声联合微泡下调CDK2蛋白和上调p27蛋白的表达,阻滞细胞周期进程,可能是抑制VSMCs增殖的机制之一。