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目的:探索携带CTLA-4 siRNA的适配子偶联脂质体颗粒是否可以激活肿瘤部位的抗肿瘤免疫反应,抑制肾细胞癌的生长。方法:采用薄膜水化法制备脂质体;使用透射电子显微镜观察脂质体的形态和结构;用Zetasizer测量Zeta电位;共孵育实验观察靶细胞对Lipo-siRNA的摄取;qPCR检测Lipo-siRNA对CTLA-4基因的沉默;小鼠移植瘤模型检测Lipo-siRNA的体内抑瘤能力;流式细胞术检测肿瘤浸润T细胞的激活状态;免疫荧光法检测肿瘤浸润T细胞的数目。结果:成功制备Lipo-siRNA,电镜结果显示其具有双层球状结构;Zetasizer测得其Zeta电位为(+20.53±2.66)mV;荧光显微镜观察结果表明Lipo-siRNA可以被靶细胞有效摄取,qPCR检测Lipo-siRNA可以显著降低CTLA-4基因的表达(P<0.001);小鼠移植瘤模型显示Lipo-siRNA较对照组而言可以显著抑制肿瘤生长(P<0.001),降低肿瘤细胞中CTLA-4的表达(P<0.001),提升肿瘤浸润T细胞的数量(P<0.000 1),并且提高了肿瘤浸润T细胞中IL-2(P<0.000 1)和IFN-γ(P<0.000 1)的表达水平。结论:适配子偶联脂质体可以携带CTLA-4 siRNA靶向肿瘤细胞,激活肿瘤部位的抗肿瘤免疫反应,抑制肿瘤的生长,对肾细胞癌的治疗具有潜在的临床应用价值。 相似文献
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Janitz Amanda E. Schraw Jeremy M. Xu Chao Lupo Philip J. 《Cancer causes & control : CCC》2022,33(3):483-488
Cancer Causes & Control - Congenital malformations are strong risk factors for childhood cancer. Our objective was to determine whether cancer survival differs by birth defect status among... 相似文献
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Praerna H. Bhargav Preethi V. Reddy Ramajayam Govindaraj Kankan Gulati Arya Ravindran D. Gayathri Sneha J. Karmani Kaviraja Udupa Ganesan Venkatasubramanian Mariamma Philip Monojit Debnath Rose Dawn Bharath T. N. Sathyaprabha Bangalore N. Gangadhar Kesavan Muralidharan 《Revue canadienne de psychiatrie》2021,66(2):179
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Carlo Romano Settanni Gianluca Ianiro Francesca Romana Ponziani Stefano Bibb Jonathan Philip Segal Giovanni Cammarota Antonio Gasbarrini 《World journal of gastroenterology : WJG》2021,27(43):7433-7445
In December 2019 a novel coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), started spreading from Wuhan city of Chinese Hubei province and rapidly became a global pandemic. Clinical symptoms of the disease range from paucisymptomatic disease to a much more severe disease. Typical symptoms of the initial phase include fever and cough, with possible progression to acute respiratory distress syndrome. Gastrointestinal manifestations such as diarrhoea, vomiting and abdominal pain are reported in a considerable number of affected individuals and may be due to the SARS-CoV-2 tropism for the peptidase angiotensin receptor 2. The intestinal homeostasis and microenvironment appear to play a major role in the pathogenesis of COVID-19 and in the enhancement of the systemic inflammatory responses. Long-term consequences of COVID-19 include respiratory disturbances and other disabling manifestations, such as fatigue and psychological impairment. To date, there is a paucity of data on the gastrointestinal sequelae of SARS-CoV-2 infection. Since COVID-19 can directly or indirectly affect the gut physiology in different ways, it is plausible that functional bowel diseases may occur after the recovery because of potential pathophysiological alterations (dysbiosis, disruption of the intestinal barrier, mucosal microinflammation, post-infectious states, immune dysregulation and psychological stress). In this review we speculate that COVID-19 can trigger irritable bowel syndrome and we discuss the potential mechanisms. 相似文献
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Megan Smith-Uffen Nicci Bartley Grace Davies Megan Best 《Patient education and counseling》2021,104(6):1325-1334
ObjectivesSingle-gene testing is associated with psycho-social challenges for cancer patients. Genomic testing may amplify these. The aim of this study was to understand patients’ motivations and barriers to pursue cancer genomic testing, to enable healthcare providers to support their patients throughout the testing process and interpretation of test results.MethodsFive databases were searched for original peer reviewed research articles published between January 2001 and September 2018 addressing motivation for genomic cancer testing. QualSyst was used to assess quality.Results182 studies were identified and 17 were included for review. Studies were heterogenous. Both somatic and germline testing were included, and 14 studies used hypothetical scenarios. 3249 participants were analyzed, aged 18 to 94. Most were female and white. The most common diagnoses were breast, ovarian, lung and colorectal cancer. Interest in testing was high. Motivations included ability to predict cancer risk, inform disease management, benefit families, and understand cancer. Barriers included concerns about cost, privacy/confidentiality, clinical utility, and psychological harm.ConclusionsDespite concerns, consumers are interested in cancer genomic testing if it can provide actionable results for themselves and their families.Practice ImplicationsProviders must manage understanding and expectations of testing and translate genetic information into health-promoting behaviours. 相似文献