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《Clinical oncology (Royal College of Radiologists (Great Britain))》2022,34(10):e421-e429
AimsTo determine the relationship between local relapse following radical radiotherapy for muscle-invasive bladder cancer (MIBC) and radiation dose.Materials and methodsPatients with T2-4N0-3M0 MIBC were recruited to a phase II study assessing the feasibility of intensity-modulated radiotherapy to the bladder and pelvic lymph nodes. Patients were planned to receive 64 Gy/32 fractions to the bladder tumour, 60 Gy/32 fractions to the involved pelvic nodes and 52 Gy/32 fractions to the uninvolved bladder and pelvic nodes. Pre-treatment set-up was informed by cone-beam CT. For patients who experienced local relapse, cystoscopy and imaging (CT/MRI) was used to reconstruct the relapse gross tumour volume (GTVrelapse) on the original planning CT . GTVrelapse D98% and D95% was determined by co-registering the relapse image to the planning CT utilising deformable image registration (DIR) and rigid image registration (RIR). Failure was classified into five types based on spatial and dosimetric criteria as follows: A (central high-dose failure), B (peripheral high-dose failure), C (central elective dose failure), D (peripheral elective dose failure) and E (extraneous dose failure).ResultsBetween June 2009 and November 2012, 38 patients were recruited. Following treatment, 18/38 (47%) patients experienced local relapse within the bladder. The median time to local relapse was 9.0 months (95% confidence interval 6.3–11.7). Seventeen of 18 patients were evaluable based on the availability of cross-sectional relapse imaging. A significant difference between DIR and RIR methods was seen. With the DIR approach, the median GTVrelapse D98% and D95% was 97% and 98% of prescribed dose, respectively. Eleven of 17 (65%) patients experienced type A failure and 6/17 (35%) patients type B failure. No patients had type C, D or E failure. MIBC failure occurred in 10/17 (59%) relapsed patients; of those, 7/11 (64%) had type A failure and 3/6 (50%) had type B failure. Non-MIBC failure occurred in 7/17 (41%) patients; 4/11 (36%) with type A failure and 3/6 (50%) with type B failure.ConclusionRelapse following radiotherapy occurred within close proximity to the original bladder tumour volume and within the planned high-dose region, suggesting possible biological causes for failure. We advise caution when considering margin reduction for future reduced high-dose radiation volume or partial bladder radiotherapy protocols. 相似文献
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ObjectivesOsteoclasts can sense the surface topography of materials. However, it is difficult to identify the structural factors that affect osteoclast formation and its function. Furthermore, we hypothesized that the type of osteoclast precursor cells also affects osteoclastogenesis in the materials. In this study, we investigated the effects of defined micro/nanoscale patterns on osteoclastogenesis from bone marrow cells (BMCs).MethodsVarious cyclo-olefin polymer (COP) patterns were prepared using nanoimprinting. The effects of shape, size, and height of the patterns, and the wettability of the patterned surfaces on osteoclastogenesis from BMCs were evaluated in vitro.ResultsOsteoclast formation was promoted on pillars (diameter, 1 μm or 500 nm; height, 500 nm). Notably, osteoclastogenesis from BMCs was better promoted on hydrophobic pillars than on hydrophilic pillars. In contrast, decreased osteoclast formation was observed on the nanopillars (diameter, 100 nm; height, 200 nm).ConclusionsWe demonstrated the promotion of osteoclast formation from BMCs on hydrophobic pillars with diameters of 1 μm and 500 nm. Some cellular behaviors in the patterns were dependent on the type of osteoclast precursor cells. The designed patterns are useful for designing the surface of dental implants or bone replacement materials with a controllable balance between osteoblast and osteoclast activities. 相似文献
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目的 探讨妇科癌症患者家属照顾者自尊与成人依恋、家庭支持缺乏的关系。方法 采用便利抽样法,选取2020年1月-2021年12月在安徽省某三甲医院妇科就诊的妇科癌症患者的家属照顾者为研究对象。采用一般资料调查问卷、照顾者反应量表(caregiver reaction assessment,CRA)、亲密关系经历量表(experiences in close relationships inventory,ECR)分别调查家属照顾者的社会人口学资料、自尊水平、家庭支持缺乏情况及成人依恋水平。结果 共发放问卷332份,回收有效问卷314份,有效回收率为94.6%。妇科癌症患者家属照顾者自尊得分为(25.12±2.61)分,依恋回避得分为(69.03±5.07)分,依恋焦虑得分为(78.32±8.54)分,家庭支持缺乏得分为(14.21±2.30)分。多元线性回归分析结果显示,照顾时间、医疗费用支付方式、患者年龄、依恋焦虑、依恋回避与家庭支持缺乏是照顾者自尊的独立影响因素(R2=0.300,△R2=0.270,F=9.156,P<0.001)。结论 在临床中应特别关注妇科癌症家属照顾者这一群体,指导他们采取合理的情绪调节策略,帮助他们增加自尊水平,使其更好地投入到妇科癌症患者的照顾中,最终提高患者的生存质量。 相似文献
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目的汉化痴呆恐惧量表,并在社区老年人中检验其信效度。方法根据Brislin翻译原则翻译痴呆恐惧量表,通过专家咨询和预试验进行文化调适,采用便利抽样法选取230名社区老年人进行问卷调查,检验中文版量表的信度和效度。结果中文版痴呆恐惧量表包含认知、社会和躯体3个维度,涉及痴呆症的体验与认识(7个条目)、担心家庭负担(4个条目)、羞耻感(3个条目)和躯体反应(4个条目)4个因子共18个条目。量表内容效度指数为0.934,各条目内容效度指数为0.857~1.000;探索性因子分析共提取4个公因子,累积方差贡献率为77.464%;总量表Cronbach′sα系数为0.893,重测信度为0.854。结论中文版痴呆恐惧量表在社区老年人中应用信效度较好,可用于老年人痴呆恐惧的识别和评估。 相似文献
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Shruti Vidhawan Agarwalla Kassapa Ellepola Nikolaos Silikas AH Castro Neto Chaminda Jayampath Seneviratne Vinicius Rosa 《Dental materials》2021,37(2):370-377
ObjectivesCandida albicanscolonizes biomaterial surfaces and are highly resistant to therapeutics. Graphene nanocoating on titanium compromises initial biofilm formation. However, its sustained antibiofilm potential is unknown. The objective of this study was to investigate the potential of graphene nanocoating to decrease long-term fungal biofilm development and hyphae growth on titanium.MethodsGraphene nanocoating was deposited twice (TiGD) or five times (TiGV) on grade 4 titanium with vacuum assisted technique and characterized with Raman spectroscopy and atomic force microscope. The biofilm formation and hyphae growth of C. albicans was monitored for seven days by CFU, XTT, confocal, mean cell density and scanning electronic microscopy (SEM). Uncoated titanium was the Control. All tests had three independent biological samples and were performed in independent triplicates. Data was analyzed with one- or two-way ANOVA and Tukey's HSD (α = 0.05).ResultsBoth TiGD and TiGV presented less biofilms at all times points compared with Control. The confocal and SEM images revealed few adhered cells on graphene coated samples, absence of hyphae and no features of a mature biofilm architecture. The increase in number of layers of graphene nanocoating did not improve its antibiofilm potential.SignificanceThe graphene nanocoating exerted a long-term persistent inhibitory effect on the biofilm formation on titanium. The fewer cells that were able to attach on graphene coated titanium were scattered and unable to form a mature biofilm with hyphae elements. The findings open opportunities to prevent microbial attachment and proliferation on implantable materials without the use of antibiotics. 相似文献