微创手术机器人机械臂结构设计与工作空间分析

目的现有双平行四边形机构设计的机械臂需要串联一个伸缩自由度机构,导致机械臂体积增大,运动灵活性降低,持镜臂与持器械臂发生干涉。针对这一问题,提出一种新型机械臂结构,增强运动灵活性、减小机械臂的体积。方法采用5连杆机构、滑块与滑轨的低副机构和丝传动机构设计机械臂,实现末端执行器的伸缩运动,建立机械臂的运动学模型,以MATLAB为仿真工具验证零位关节角D-H参数的正确性,求解出机械臂的运动方程;同时运用蒙特卡洛算法,得到末端执行器的三维工作空间范围,并对3条机械臂作术前动物实验规划;最后,在猪体内进行胆囊切除等操作,验证机械臂的双5连杆2自由度设计的合理性和可操作性。结果蒙特卡洛算法在MATLAB环境下得到的工作空间范围为:-650.4 mmx649 mm,163.8 mmy1 202 mm,-254.6 mmz829.8 mm,并成功完成16例猪的胆囊切除实验,平均操作时间为51 min。结论新型设计的双5连杆2自由度机械臂在猪体内成功完成胆囊切除等操作,且猪术后无其他不良症状,机械臂之间的运动无干涉,充分验证了所提出的微创手术机器人机械臂设计方案的可行性。     

99Tcm-MIBI SPECT/CT同机融合显像在卵巢恶性肿瘤诊断中的应用价值

近几年来,在SPECT/CT同机融合显像技术的高速发展下,广泛应用于临床的亲肿瘤示踪显像剂99Tc^m-MIBI在卵巢恶性肿瘤的早期诊断方面展现了越来越大的应用价值。本文介绍了显像剂99Tc^m-MIBI的显像机制以及多模态影像学技术,并阐明了99Tc^m-MIBISPECT/CT同机融合显像技术在卵巢恶性肿瘤诊断中的临床应用价值。     

HER2在上皮性卵巢癌中的研究进展

HER2是原癌基因HER2/neu编码的跨膜糖蛋白,可以通过IHC、FISH和分子影像等方法测定。这种癌基因在不同组织学分型和临床分期的上皮性卵巢癌中的表达对预后和治疗靶值的临床应用已被广泛研究,但是目前尚无一致意见。近期的文献中表明HER2过度表达与低分化晚期肿瘤及化疗耐药和生存期缩短有关。对于晚期卵巢癌患者,最初先行减压手术和紫杉醇、铂类药物组合的标准治疗,但后来发展为化疗耐药性疾病,因此需要更多的治疗方法来提高患者生存率。近年来针对HER2的靶向治疗成为临床研究的热点。     

Rapamycin attenuates Tc1 and Tc17 cell responses in cigarette smoke-induced emphysema in mice

Inflammation Research - Chronic exposure to cigarette smoke promotes airway inflammation and emphysema accompanied by enhanced CD8+ interferon (IFN)-γ+ T(Tc1) and CD8+ interleukin (IL)-17+...     

MiR-19a mediates the negative regulation of the NF-κB pathway in lipopolysaccharide-induced endometritis by targeting TBK1

Objective

In both humans and animals, endometritis is severe inflammation of the uterus, and it causes great economic losses in dairy cow production. MicroRNAs have been reported to play an important role in various inflammatory diseases. However, the regulatory mechanisms of miR-19a in endometritis remain unclear. Thus, the aims of this study are to investigate the role of miR-19a in a mouse model of lipopolysaccharide (LPS)-induced endometritis and elucidate the possible mechanisms in bovine endometrial epithelial cells (bEECs).

Methods and results

Histological analysis showed that LPS induced severe pathological changes, suggesting that the endometritis mouse model was well established. The qPCR assay indicated that miR-19a expression in the uterine tissues of mice with endometritis and in bEECs with LPS stimulation was significantly reduced. The overexpression of miR-19a significantly decreased the expression of inflammatory cytokines (TNF-α, IL-6 and IL-1β) and the phosphorylation of NF-κB p65 and IκBα. Similar results were also obtained following the knockdown of TBK1. Furthermore, a dual luciferase reporter assay further validated that miR-19a inhibited TBK1 expression by binding directly to the 3′-UTR of TBK1.

Conclusion

We demonstrated that miR-19a has anti-inflammatory effects and mediates the negative regulation of the NF-κB Pathway in LPS-induced endometritis by targeting TBK1.

     

Peripheral blood leukocyte telomere length is associated with age but not renal function: A cross-sectional follow-up study

Objectives

We aimed to evaluate the relationship between baseline renal function and changes in telomere length in Han Chinese.

Methods

The telomere restriction fragment (TRF) length of leukocytes in the peripheral blood was measured in healthy volunteers recruited in 2014. The estimated glomerular filtration rate (eGFR) was calculated based on serum creatinine (Scr) and serum cystatin C (CysC)-eGFRcys and eGFRScr-cys through the Cockcroft-Gault formula (eGFRC-G) or the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI / eGFRCKD-EPI) equation. The correlation between telomere length changes over time and renal function was analyzed.

Results

Leukocyte TRF lengths were negatively correlated to age (r = -0.393, p < 0.001) and serum CysC (r = -0.180, p < 0.01), while positively associated with eGFRCKD-EPI, eGFRC-G, eGFRcys, and eGFRScr-cys (r = 0.182, 0.122, 0.290, and 0.254 respectively, p < 0.01). The 3-year change of telomere length was 46 bp/years. When adjusted for age, the associations between telomere length changes and baseline, subsequent TRF lengths, and serum CysC were no longer present. No association was observed between TRF length changes and renal function.

Conclusion

The rate of telomere length changes was affected by age and baseline telomere length. The telomere length changes might be important markers for aging.