Nanotechnology for colorectal cancer detection and treatment

Colorectal cancer (CRC) is the third most diagnosed cancer and the second leading cause of cancer-related mortality in the United States. Across the globe, people in the age group older than 50 are at a higher risk of CRC. Genetic and environmental risk factors play a significant role in the development of CRC. If detected early, CRC is preventable and treatable. Currently, available screening methods and therapies for CRC treatment reduce the incidence rate among the population, but the micrometastasis of cancer may lead to recurrence. Therefore, the challenge is to develop an alternative therapy to overcome this complication. Nanotechnology plays a vital role in cancer treatment and offers targeted chemotherapies directly and selectively to cancer cells, with enhanced therapeutic efficacy. Additionally, nanotechnology elevates the chances of patient survival in comparison to traditional chemotherapies. The potential of nanoparticles includes that they may be used simultaneously for diagnosis and treatment. These exciting properties of nanoparticles have enticed researchers worldwide to unveil their use in early CRC detection and as effective treatment. This review discusses contemporary methods of CRC screening and therapies for CRC treatment, while the primary focus is on the theranostic approach of nanotechnology in CRC treatment and its prospects. In addition, this review aims to provide knowledge on the advancement of nanotechnology in CRC and as a starting point for researchers to think about new therapeutic approaches using nanotechnology.     

主动脉出口血压对左心室血流特性的影响

采用Mimics对心脏进行三维重构，用3-matic进行模型优化以及模型误差分析，对左心室室壁运动做速度分布假设，基于UDF宏文件对左心室室壁运动编写程序，将血液视为非牛顿流体，采用动网格技术研究不同血压对左心室血液流动的影响。模拟发现当左心室收缩时，压力梯度明显，内部压力减小。当左心室舒张时，内部压力逐渐增高。二尖瓣口处的速率先增大后减小。血压升高，左心室内剪切应力持续增大，极易破坏红细胞结构，产生溶血现象，导致心脏功能紊乱。     

Clinical presentation,management, screening and surveillance for colorectal cancer during the COVID-19 pandemic

Management of colorectal cancer (CRC) was severely affected by the changes implemented during the pandemic, and this resulted in delayed elective presentation, increased emergency presentation, reduced screening and delayed definitive therapy. This review was conducted to analyze the impact of the coronavirus disease 2019 (COVID-19) pandemic on management of CRC and to identify the changes made in order to adapt to the pandemic. We performed a literature search in PubMed, Medline, Index Medicus, EMBASE, SCOPUS, Reference Citation Analysis (https://www.referencecitationanalysis.com/) and Google Scholar using the following keywords in various combinations: Colorectal cancer, elective surgery, emergency surgery, stage upgrading, screening, surveillance and the COVID-19 pandemic. Only studies published in English were included. To curtail the spread of COVID-19 infection, there were modifications made in the management of CRC. Screening was limited to high risk individuals, and the screening tests of choice during the pandemic were fecal occult blood test, fecal immunochemical test and stool DNA testing. The use of capsule colonoscopy and open access colonoscopy was also encouraged. Blood-based tests like serum methylated septin 9 were also encouraged for screening of CRC during the pandemic. The presentation of CRC was also affected by the pandemic with more patients presenting with emergencies like obstruction and perforation. Stage migration was also observed during the pandemic with more patients presenting with more advanced tumors. The operative therapy of CRC was altered by the pandemic as more emergencies surgeries were done, which may require exteriorization by stoma. This was to reduce the morbidity associated with anastomosis and encourage early discharge from the hospital. There was also an initial reduction in laparoscopic surgical procedures due to the fear of aerosols and COVID-19 infection. As we gradually come out of the pandemic, we should remember the lessons learned and continue to apply them even after the pandemic passes.     

健脾消癌方通过PI3K/Akt信号通路抑制结肠癌血管生成的研究＊

目的 观察结肠癌HCT116细胞健脾消癌方的条件培养液对HUVEC细胞管腔形成的影响，从PI3K/Akt生物轴调控角度探讨其作用机制。方法 培养HCT116细胞，细胞设3组：对照组，健脾消癌方组（加入15%健脾消癌方含药血清）及人参皂苷Rg3组；制备HCT116细胞健脾消癌方条件培养液（分组及制备方法见实验方法），用条件培养液干预HUVEC（脐静脉内皮细胞，Human Umbilical Vein Endothelial Cells），Matrigel基质胶法检测HCT116细胞健脾消癌方条件培养液对HUVEC小管形成的影响。随后采用蛋白免疫印迹法（Western blot）检测各组HCT116细胞磷脂酰肌醇3-激酶（PI3K）、蛋白激酶B（Akt）、p-Akt、VEGF（血管内皮生长因子，Vascular endothelial growth factor）蛋白表达。最后在结肠癌HCT116荷瘤小鼠中验证健脾消癌方对肿瘤生长速度的影响，并经瘤组织VEGF蛋白表达、CD31免疫组化染色检测肿瘤内血管生成情况。结果 模型组HUVEC细胞管腔形成较空白血清组显著增加（P<0.05）；健脾消癌方组及人参皂苷Rg3组较模型组HUVEC细胞管腔形成显著减少（P<0.01）。p-Akt和VEGF蛋白表达水平模型组高于空白血清组（P<0.05），健脾消癌方组及人参皂苷Rg3组显著低于模型组（P<0.01）；PI3K、Akt蛋白表达量组间差异无统计学意义。与对照组比较，模型组荷瘤小鼠肿瘤体积显著性增大，瘤组织内VEGF表达、CD31阳性面积显著性增加，差异有统计学意义（P<0.05）；与模型组比较，健脾消癌方组及人参皂苷Rg3组荷瘤小鼠肿瘤体积显著减小，瘤组织内VEGF表达、CD31阳性面积降低，差异有统计学意义（P<0.05）。结论 健脾消癌方可抑制肿瘤的血管生成和生长，其作用机制可能与PI3K/Akt生物轴调控VEGF表达有关。     

北京市三级甲等医院结直肠癌患者就医流向规律分析

目的 分析不同特征的结直肠癌患者就医行为选择在中医院（含中西医结合医院）、西医院及肿瘤专科医院间的差异，为合理引导结直肠癌患者适宜就医及制订相关政策提供依据。方法 收集北京地区2018年1月-2019年12月17家三级甲等医院21894例首诊结直肠癌成年住院患者的病案首页数据，采用EmpowerStats 2.0对数据进行描述性分析。结果 21894例结直肠癌患者中就诊于中医院的有862例（3.93%），西医院的有8723例（39.85%），肿瘤专科医院的有12309例（56.22%）。对于不同医疗机构，男性占比均大于女性，58-68岁患者占比最大。且结直肠癌患者年龄、医疗付款方式及肿瘤分期在不同医疗机构间的分布存在差异（P<0.001）。西医院及肿瘤专科医院结直肠癌Ⅲ期患者占比最大，而就诊于中医院患者中结直肠癌Ⅳ期最多。从地域分布来看，异地就诊比例（57.32%）大于本地，且就诊于肿瘤专科医院的患者中73.66%来自外地。患者来源前三名分别是北京市、河北省及内蒙古自治区。而在北京市内，西医院患者主要来源于朝阳区、海淀区及西城区，中医院患者主要来源于海淀区、朝阳区及丰台区，肿瘤专科医院则主要来源于朝阳区、海淀区及丰台区。结论 应大力倡导年轻以及早期结直肠癌患者向中医院分流，充分施展中医药在结直肠癌患者中的治疗优势；发挥三级医院带动作用，建立对口帮扶医院，减少不必要的跨省流动及提倡结直肠癌的早筛早治，以降低结直肠癌死亡率。     

保乳术后放疗中钛夹动度与乳腺大小及钛夹位置的相关性

【摘要】目的:分析保乳术后放疗患者钛夹动度，并探讨其与乳腺大小、钛夹位置的相关性。方法:随机选取保乳术后放疗患者15例，每周两次锥形束CT。测量乳腺基底面直径（D）和乳高轴（H），以瘤床质心为原点将临床靶区分4个象限。记录各象限内钛夹在左右、腹背、头脚方向动度（MLR、MAP、MSI）以及其与临床靶区最内、最前、最上的距离（DSLR、DSAP、DSSI）。结果:MLR、MAP、MSI分别为（2.2±3.0）、（-1.1±3.6）、（0.8±4.7） mm；系统误差Σ在左、右、腹、背、头、脚分别为1.7、2.2、2.0、2.4、2.9、3.0 mm，随机误差σ分别为2.4、4.0、3.2、4.0、4.7、4.7 mm；靶区对应外放5.9、8.3、7.2、8.8、10.5、10.9 mm。一象限内，当D×H<99.89 cm2，MAP和D×H强相关（r=0.805），MLR、MAP均和DSLR、DSAP、DSSI强正相关（r=0.94, 0.94, 0.91；0.87, 0.91, 0.92），MSI和DSLR、DSAP强正相关（r=0.91, 0.94）；四象限内，当D×H<90.71 cm2，MAP和DSLR，MSI和DSAP均强负相关（r=-0.96；-0.95），MLR和DSLR强正相关（r=0.91）。结论:钛夹动度有各向异性，以SI方向外扩最大，并易受乳腺大小、钛夹位置影响。     

基于CiteSpace的结直肠癌患者生命质量研究

目的：通过中英文文献了解结直肠癌患者生命质量研究现状及发展趋势。方法：运用CiteSpace对中国知网（CNKI）、万方数据知识服务平台、中国生物医学文献数据库、Web of Science核心数据集、PubMed、Cochrane Library中收录的关于结直肠癌患者生命质量研究的中英文文献进行可视化分析。结果：检索得到中文文献1 285篇，英文文献871篇，中英文文献发文量均呈上升趋势，相关研究关注的重点主要是结直肠癌患者造口、抑郁、免疫、肠道功能、化疗及化疗药物，但机构之间、学者之间合作程度及研究类型等方面存在一定差异。结论：中文文献相关研究起步晚、发展快，但在研究质量与研究深度等方面与英文文献相比还有一定差距；国内学者之间、机构之间应加强合作，关心患者肠道功能、心理状况，提高患者体力活动水平，开展更多高质量研究。