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1.
Bioreducible heparin (HEP)-based nanogels were prepared by derivatizing HEP with vinyl group followed by copolymerizing with cystamine bisacrylamide in aqueous medium in the absence of surfactant. The hydrodynamic diameter of the HEP nanogels could be tuned in the range from 80 to 200 nm. Doxorubicin (DOX) was loaded into the HEP nanogels, and high drug loading content (30%) and efficiency (90%) were achieved. In vitro drug release test revealed that this drug delivery system exhibited strongly redox-sensitive drug release behavior that would greatly favor the in vivo drug delivery performance of the nanogels. After injected into tumor-bearing mice through tail vein, the DOX-loaded HEP nanogels showed remarkable accumulation in tumors as demonstrated by in vivo near infared fluorescence imaging and ex vivo DOX concentration measurements. The doxorubicin accumulation at tumor site goes beyond 9% injected dose per gram of tumor through such delivery system, making that DOX-loaded HEP nanogels have significantly superior in vivo antitumor activity.  相似文献   
2.
《药学学报(英文版)》2020,10(7):1294-1308
A great challenge in multi-targeting drug discovery is to identify drug-like lead compounds with therapeutic advantages over single target inhibitors and drug combinations. Inspired by our previous efforts in designing antitumor evodiamine derivatives, herein selective histone deacetylase 1 (HDAC1) and topoisomerase 2 (TOP2) dual inhibitors were successfully identified, which showed potent in vitro and in vivo antitumor potency. Particularly, compound 30a was orally active and possessed excellent in vivo antitumor activity in the HCT116 xenograft model (TGI = 75.2%, 150 mg/kg, p.o.) without significant toxicity, which was more potent than HDAC inhibitor vorinostat, TOP inhibitor evodiamine and their combination. Taken together, this study highlights the therapeutic advantages of evodiamine-based HDAC1/TOP2 dual inhibitors and provides valuable leads for the development of novel multi-targeting antitumor agents.  相似文献   
3.
目的 研究miR-200、miR-155及血管新生因子与原因不明复发性流产(unexplained recurrent spontaneousabortion,URSA)的相关性分析。 方法 选择2015年3月—2018年1月在青岛市妇女儿童医院妇产科就诊的URSA患者作为URSA组、要求终止妊娠的正常早孕患者作为对照组,检测绒毛组织中微小RNA(microRNA, miR)miR-200、miR-155、血管内皮生长因子(vascular endothelial growth factor,VEGF)、可溶性FMS样酪氨酸激酶1(soluble FMS like tyrosine kinase-1,sFlt-1)的表达量及血清中VEGF、sFlt-1的含量,对miR-200、miR-155靶向结合VEGF、sFlt-1进行生物信息学分析。 结果 URSA组的绒毛组织中miR-200(1.78±0.32 vs. 0.91±0.15)、sFlt-1(1.87±0.35 vs. 1.06±0.21)的相对表达量及血清中sFlt-1的含量[(12.39±2.31)ng/ml vs. (6.51±0.95)ng/ml]均高于对照组,差异有统计学意义(均P<0.05)。绒毛组织中miR-155相对表达量(0.60±0.10 vs. 0.93±0.16)、VEGF mRNA相对表达量(0.59±0.09 vs. 1.02±0.16)及蛋白表达量(0.62±0.07 vs. 1.04±0.18)、血清中VEGF的含量[(601.25±94.39)ng/ml vs. (935.12±132.47)ng/ml]低于对照组,差异有统计学意义(均P<0.05);URSA组患者绒毛组织中miR-200的表达量与血清中VEGF的含量、绒毛组织中VEGF的表达量均呈负相关,绒毛组织中miR-155的表达量与血清中sFlt-1的含量和绒毛组织中sFlt-1的表达量均呈负相关;miR-200、miR-155分别靶向结合VEGF、sFlt-1基因的3’UTR。 结论 miR-200表达增多、miR-155表达减少与URSA发生有关,miR-200靶向VEGF、miR-155靶向sFlt-1是介导该过程的可能机制。  相似文献   
4.
作者用同位数前体参入法及透射与扫描电镜研究了平阳霉素(博莱霉素A_5)对HeLa细胞大分子生物合成及超微结构的影响。结果显示:平阳霉素能抑制HeLa细胞DNA,RNA和蛋白质的生物合成,对DNA的抑制作用强,ID_(50DNA)为42.77μg/ml。表现为:染色质减少,核内电子密度低,核仁分离及“核仁帽”形成,细胞表面微绒毛消失或变形,最终导致质膜破裂等。作者认为,细胞膜是否为此类药物作用的靶位值得进一步研究。  相似文献   
5.
6.
A case of angiolipoma occurring in the buccal mucosa of a 69-year-old male is described. The patient had noticed a painless mass in his buccal mucosa for 2 years. The surgically removed tumor, measuring 9 mm in diameter, was mainly located in the submucosal layer with focal expansion into the muscle layer. Histologically, the tumor was well-demarcated and composed of proliferations of mature fat cells and fibrous connective tissue containing many small blood vessels, which were evenly distributed. There was diffuse infiltration of a large number of mast cells, which were immunopositive for vascular endothelial growth factor (VEGF) especially around blood vessels, suggesting that VEGF produced by mast cells in angiolipomas plays an important role in the vascular proliferation in this particular tumor.  相似文献   
7.
瘤性体液中肿瘤血管生长因子的提取和检测   总被引:1,自引:0,他引:1  
《肿瘤防治杂志》2005,12(17):1289-1291
  相似文献   
8.
食管鳞癌中肿瘤微血管密度的临床意义   总被引:1,自引:0,他引:1  
范虹  曾亮  王群 《复旦学报(医学版)》2004,31(2):162-164,168,F005
目的 研究分析食管癌组织中肿瘤微血管密度 (MVD)的临床意义。方法 采用免疫组化的方法检测4 5例食管鳞癌根治性切除术后的肿瘤组织中的肿瘤微血管密度 ,应用SPSS统计软件分析肿瘤MVD与食管鳞癌临床病理参数及预后的关系。结果 本组病例中 ,肿瘤MVD平均值为 15 .5 8,中位值为 15。MVD水平与食管癌的肿瘤局部浸润程度、区域淋巴结转移及TNM分期有关 (P <0 .0 5 )。多血管型 (MVD >15 )病例的术后生存率低于少血管型 (MVD≤ 15 )病例 (P =0 .0 2 78)。Cox比例风险模型证实MVD水平是食管癌根治性切除病人预后的独立预测指标。结论 食管鳞癌的血管新生与癌肿进展程度有关 ,高MVD的食管鳞癌患者术后生存率明显低于低MVD的患者 ,其MVD水平可独立用于预测食管癌根治性切除病人的预后  相似文献   
9.
BACKGROUND: Although it is clear that dissemination via the blood system involves angiogenesis, it is uncertain whether tumors also induce lymphangiogenesis or simply invade existing peritumoral vessels. The purpose of this study was to elucidate changes in tumor blood and lymph vessels in cases involving the invasion of squamous cell carcinoma in the oral cavity, and its significance. Blood and lymph vessels densities in tongue carcinomas induced in hamsters were investigated. METHODS: Tongue cancer was induced by abrading the right margin of the tongue of each hamster with an endodontic barbed broach and subsequently applying 1.0% 9,10-dimenthl-1,2-benzanthracene (DMBA) dissolved in acetone, three times a week, at the same site. Fresh frozen sections were prepared and blood vessels stained blue by perfusion with Coomassie Brilliant Blue and lymph vessels stained brown for 5'-nucleotidase. The effects on the blood vessels and lymph vessels were observed. RESULTS: The results showed that blood and lymph vessel densities were greater in the advanced carcinoma tissues than in normal tissue. These were compared in terms of the mode of cancer invasion. As tumor invasion progressed, the blood vessel density decreased but lymph vessel density tended to be higher in high-degree tumor invasion than in low-degree tumor invasion. The expression of vascular endothelial growth factor-C was seen more frequently as tumor invasion progressed. CONCLUSIONS: The present findings indicated that angiogenesis and lymphangiogenesis are affected by cancerous invasion.  相似文献   
10.
毛喉萜对人肝癌细胞增殖影响的实验研究   总被引:1,自引:0,他引:1  
目的 探讨毛喉萜 (Forskolin)的抗肝癌作用。方法 采用克隆形成、MTT比色法观察毛喉萜对SMMC 772 1细胞的作用 ,并利用免疫细胞化学方法检测其对rasp2 1、p5 3蛋白表达的影响。结果 毛喉萜可明显抑制SMMC 772 1细胞的增殖 ,其抑制率与剂量呈正相关 (P <0 .0 1 ) ,经毛喉萜处理后 ,rasp2 1、p5 3蛋白表达均有明显下降。结论 毛喉萜能明显抑制肝癌SMMC 772 1细胞增殖 ,其作用可能与降低rasp2 1、p5 3蛋白表达有关。  相似文献   
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