Assessment of dental implant surface stability at the nanoscale level

ObjectivesTo study the oxide layer stability of certified dental implants of system "P", made based on TiO₂ alloy with carbon coating. To perform a comparative statistical analysis of the obtained data with the available data for the dental implants of systems "A" and "B".MethodsX-ray microtomography and X-ray fluorescence analysis were used to study soft tissue biopsy specimens. Supernatants were studied by dynamic light scattering and transmission electron microscopy when simulating free emission of nanoscale metal oxide particles from the surface of dental implants as well as when simulating physical loading. A comparative analysis of three parameters of nanoscale particles was performed by statistical data analysis. The surface of the "P" system dental implant with surface treatment was analyzed by scanning electron microscopy.ResultsBoth free emission of nanoscale oxide layer particles and yield of nano- and microscale particles during simulation of physical load were confirmed. Statistically significant differences were noted in a comparative analysis of the size and frequency of occurrence of these particles in the supernatants obtained from the surfaces of three dental implant systems. The elemental composition of the particles and the composition and structure of the "P" system dental implants themselves were analyzed.SignificanceThe developed method of dynamic light scattering can be used to compare the stability of the oxide layer of standardized medical products manufactured on the basis of the TiO₂ alloy.     

Center of pressure position in the touches of the star excursion balance test in healthy individuals

BackgroundThe Star Excursion Balance Test (SEBT) is a clinical test that aims to assess postural control. Its interpretation is related to the understanding of the motor specificities required. Adjustments must be made to the center of pressure (COP) to maintain balance during testing movements. Comprehend the specifics of these adjustments for each direction can allow the development of more suitable exercises for balance training. The aim was to compare the positions of the COP on the different directions of the SEBT and correlate the reachs obtained in the SEBT with the distances from the COP to the borders of the base of support (BOS).MethodsSixteen healthy subjects participated in the study. Measurements were made by performing the SEBT over the force platform. The Kruskal-Wallis test followed by Bonferroni's post hoc test was used to compare directions. The Pearson correlation test was used to check the correlation of parametric variables and Spearman correlation test for the nonparametric ones.ResultsThe position of the COP at the touch differs from the anterior direction to the other directions of the SEBT and the performance in this direction is correlated with the proximity of the COP to the anterior limit of the support base. The performances in the other directions did not correlate with the COP position.ConclusionThe requirements of the compensation mechanisms for postural control are different between the directions of the SEBT.     

DCE-MRI诊断原发性肝癌效能和TACE术后评估肿瘤活性应用价值研究*

目的 探讨动态对比增强磁共振成像(DCE-MRI)检查诊断原发性肝癌(PLC)患者的效能及评价疗效的价值。方法 2017年1月～2021年6月我院诊治的肝占位性病变患者68例,均接受DCE-MRI检查,并行穿刺细胞学检查诊断,应用临床流行病学基本技术评估MRI诊断的效能。所有PLC患者接受经皮肝动脉化疗栓塞术(TACE)治疗,术后再次接受MRI检查,评估疗效。结果 DCE-MRI检查显示PLC患者肝内特征性恶性肿瘤表现,T1WI序列为低信号,T2WI序列为高信号,动脉期明显强化,门脉期快速消退,偶见明显的肿瘤包膜;在68例肝占位性病变患者,经穿刺细胞学检查,诊断PLC患者64例,非肿瘤病变4例;DCE-MRI检查诊断的灵敏度、特异度、准确率、阳性和阴性预测值分别为95.2%、75.0%、89.7%、93.8%和25.0%;在TACE术后,MRI检查发现肿瘤被完全灭活18例(28.1%),部分灭活25例(39.1%),肿瘤稳定15例(23.4%),疾病进展6例(9.3%)。结论 DCE-MRI检查在诊断PLC和治疗后疗效判断方面有独特的作用,可指导临床制定治疗方案,价值很大。     

滋肾育胎丸加减方预防ACA阳性者不良妊娠结局的效果及机制研究＊

目的 探讨滋肾育胎丸加减方预防抗磷脂抗体（ACA）阳性者不良妊娠结局的效果及机制研究。方法 选取2016年2月至2019年2月我院收治的89例ACA阳性，先兆性流产或有习惯性流产（RSA）史患者，将采用西医治疗的40例作为对照组，将采用西医联合滋肾育胎丸加减方治疗的49例作为观察组，比较两组中医证候疗效、中医证候积分、ACA-IgA、ACA-IgM、ACA-IgG、凝血指标［血小板聚集功能（PAF）、活化蛋白C（PC）、抗凝血酶（AT）、纤溶酶原激活抑制物-1（PAI-1）］、Th1/Th2细胞因子［干扰素γ（IFN-γ）、白介素-2（IL-2）、白介素-4（IL-4）、白介素-10（IL-10）］、妊娠结局、安全性。结果 治疗2周后检测ACA，观察组2例未降低，对照组11例未降低，观察组未降低患者占比低于对照组（P<0.05）；观察组总有效率100.00%高于对照组85.00%（P<0.05）；观察组治疗4周、7周后中医证候积分低于对照组（P<0.05）；观察组治疗4周、7周后ACA-IgA、ACA-IgM、ACA-IgG低于对照组（P<0.05）；观察组治疗4周、7周后PAF、PAI-1低于对照组，PC、AT高于对照组（P<0.05）；观察组治疗4周、7周后IFN-γ、IL-2低于对照组，IL-4、IL-10高于对照组（P<0.05）；观察组活产率95.92%高于对照组80.00%（P<0.05）；组间不良反应总发生率比较，差异无统计学意义（P>0.05）。结论 动态监测ACA对滋肾育胎丸加减方精准应用具有指导意义，指导滋肾育胎丸加减方通过调理脏腑、气血、经络功能，改善先兆性流产或有RSA史患者临床症状及凝血因子指标，降低ACA水平，并可改善患者免疫耐受功能，提高胎儿活产率，且安全性高。     

Reliability and criterion validity of two-dimensional movement assessments in those with patellofemoral pain

ObjectivesDetermine criterion validity and intra/inter-rater reliability of 2-dimensional (2D) knee frontal plane projection angle (kFPPA), hip frontal plane projection angle (hFPPA), and dynamic valgus index (DVI) during forward step-downs in those with patellofemoral pain (PFP).DesignCross-sectional.SettingUniversity research laboratory.Participants39 participants with PFP (34.18 ± 7.41years, 170± .1 cm, 81.03 ± 19.36 kg, duration of pain: 68.67 ± 85.08months, anterior knee pain scale: 80.49 ± 7.87, visual analog scale:2.08 ± 2.02)Main outcome measuresAverage 3D hip and knee sagittal, frontal, and transverse joint angles and 2D kFPPA, hFPPA, and DVI at maximum knee flexion were variables of interest. 3D DVI was calculated as the sum of hip and knee frontal and transverse angles. 2D kFPPA, hFPPA, and DVI were calculated by two raters independently on two occasions.ResultsIntra- and inter-rater reliability of all 2D angles were excellent. kFPPA was moderately correlated to 3D knee transverse angles. hFPPA was moderately correlated to 3D hip frontal and transverse angles and largely correlated to 3D DVI. 2D DVI was moderately correlated to hip transverse angles.ConclusionkFPPA, hFPPA, and DVI are reliable. hFPPA may be reflective of 3D hip and knee frontal and transverse motion during forward step-downs in those with PFP.     

动态增强MRI成像在鼻咽癌诊疗中的应用价值

动态增强磁共振成像(Dynamic contrast enhanced MRI,DCE-MRI)是一种非常有价值的定量MRI技术,在提高肿瘤诊断的敏感度、良恶性肿瘤的鉴别、肿瘤分级等方面有良好的应用价值。本文就鼻咽癌分期、疗效评价、鉴别鼻咽癌放疗后瘢痕纤维化与肿瘤复发的DCE-MRI研究现状进行综述,供同道们在工作中参考。     

近红外荧光成像技术在外科手术中的研究进展

作为术中导航的新兴领域,近红外荧光(near-infrared fluorescence,NIRF)成像技术能借助荧光探针对特定的生物组织进行显像,从而在外科手术中实时获取血管、淋巴管和特定组织的视觉信息,从而发现传统方法无法识别的微小灶,正确显示肿瘤切缘,帮助外科医生进行术中决策。该技术由于其操作简单,快速实时,安全无害,具有良好的应用前景。本文将就NIRF成像技术的基本原理,在实时引导肿瘤切除,前哨淋巴结定位,保护正常解剖结构等方面的临床进展进行综述,并且讨论了该技术的局限性和优势并展望其应用前景。     

基于MRI动态图像观察吞咽时器官动度对头颈部肿瘤调强放疗靶区影响

目的 利用MRI技术连续采集头颈部肿瘤患者吞咽时图像,观察并测量软腭、舌、喉的运动规律及最大活动度。方法 随机选取2018年7月-10月在中国医学科学院肿瘤医院接受调强放疗的原发头颈部恶性肿瘤20例患者,其中男17例、女3例,中位年龄58.5岁(28~78岁)。20例患者中鼻咽癌7例,口腔癌3例,口咽癌5例,下咽癌3例,鼻腔鼻旁窦2例。根据AJCC第八版分期Ⅰ-Ⅱ期患者2例,Ⅲ期8例,Ⅳ期10例。结果 吞咽时软腭向上移动移动距离为(1.06±0.31) cm且服从正态分布,向后移动距离为(0.83±0.24) cm且近似正态分布。舌体向后移动距离为(0.77±0.22) cm,且服从正态分布。含压舌板行图像采集患者舌上移位移为0,无压舌板患者舌体中位上移距离为1.23 cm (0.59~1.41 cm)。喉向上移动距离为(1.14±0.22) cm且服从正态分布,向前移动的中位距离为0.4 cm (0.27~0.90 cm)。结论 吞咽运动有可能发生于头颈部肿瘤患者放疗过程中,并引起大体肿瘤体积(GTV)及周围正常组织移动;因此在制定放疗计划时应注意GTV至PGTV的个体化外放距离,以保证肿瘤处方剂量。