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排序方式: 共有127条查询结果,搜索用时 15 毫秒
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Boshi Tian Shaohua Liu Chenghao Yu Shikai Liu Shuming Dong Lili Feng Narisu Hu Piaoping Yang 《Advanced functional materials》2023,33(25):2300818
As a less O2-dependent photodynamic therapy (PDT), type I PDT is an effective approach to overcome the hypoxia-induced low efficiency against solid tumors. However, the commonly used metal-involved agents suffer from the long-term biosafety concern. Herein, a metal-free type I photosensitizer, N-doped carbon dots/mesoporous silica nanoparticles (NCDs/MSN, ≈40 nm) nanohybrid with peroxidase (POD)-like activity for synergistic PDT and enzyme-activity treatment, is developed on gram scale via a facile one-pot strategy through mixing carbon source and silica precursor with the assistance of template. Benefiting from the narrow bandgap (1.92 eV) and good charge separation capacity of NCDs/MSN, upon 640 nm light irradiation, the excited electrons in the conduction band can effectively generate O2•− by reduction of dissolved O2 via a one-electron transfer process even under hypoxic conditions, inducing apoptosis of tumor cells. Moreover, the photoinduced O2•− can partially transform into more toxic •OH through a two-electron reduction. Moreover, the POD-like activity of NCDs/MSN can catalyze the endogenous H2O2 to •OH in the tumor microenvironment, further synergistically ablating 4T1 tumor cells. Therefore, a mass production way to synthesize a novel metal-free type I photosensitizer with enzyme-mimic activity for synergistic treatment of hypoxic tumors is provided, which exhibits promising clinical translation prospects. 相似文献
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Francesca Giuntini Daniele NistriGiacomo Chiti Lia FantettiGiulio Jori Gabrio Roncucci 《Tetrahedron letters》2003,44(3):515-517
The base-catalyzed cyclotetramerization of 3-, 4- and 4,5-dimethylaminophenylthio phthalonitriles with zinc(II)acetate afforded 1(4),8(11),15(18),22(25)- and 2(3),9(10),16(17),23(24)-tetrasubstituted and 2,3,9,10,16,17,23,24-octasubstituted Zn(II)phthalocyanines, respectively. The statistical mixed condensation of the same phthalonitriles with 1,2-dicyanobenzene gave the corresponding mono- and disubstituted derivatives. Methylation of such products afforded a series of cationic Zn(II)phthalocyanines with different pattern of substitution, with potential use as photodynamic agents in microbial infections. 相似文献
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A hybrid PDMS/glass microfluidic system for evaluation of the efficiency of photodynamic therapy is presented. 5-aminolevulinic acid (ALA) was used as a precursor of photosensitizer. The geometry of the microdevice presented in this paper enables to test different concentrations of the photosensitizer in a single assay. The viability of the A549 cells was determined 24 h after PDT procedure (irradiation with light which induced a photosensitizer accumulated in carcinoma cells, λ = 625 nm). The presented results confirmed the possibility to perform the photodynamic therapy process in vitro in microscale and the possibility to assess its effectiveness. Moreover, because two identical microstructures on a single chip were performed, the microchip can be used for examination simultaneously various cell lines (carcinoma and normal) or various photosensitizers. 相似文献
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目的 :通过细胞学水平研究确定ALA配合小剂量HPD激光光动力疗法促使肿细胞死亡及凋亡的光敏药用药剂量及与二者单独使用的差别方法 :以不同剂量的ALA(40 μg/ml、80 μg/ml、16 0 μg/ml)、HPD(2 .5 μg/ml、5 μg/ml、10 μg/ml)、二者联合与S180腹水瘤细胞一起培养 ,随后以 6 30nm半导体激光 2 0 0mW /cm2 ,照射肿瘤细胞 ,照射 2 0分钟 ,及与不用光敏剂单照激光、单用光敏剂不照光、不用光敏剂不照激光空白对照组比较。以流式细胞仪及倒置微镜观察促使肿瘤细胞凋亡或死亡的差别 ,寻找促使肿瘤细胞凋亡或死亡的最小合适剂量。结果 :ALA4 0 μg/ml配合HPD2 .5 μg/ml与S180腹水瘤细胞同时培养 ,6 30半导体激光 2 0 0mW /cm2 ,照射 2 0分钟组从形态学观察及流式细胞仪测定是能达到较佳的细胞凋亡的最小用光敏剂剂量。单纯ALA -PDT组中能达到小鼠S180腹水瘤细胞明显凋亡的最小剂量是ALA(80 μg/ml) ,单纯HPD -PDT组中能达到小鼠S180腹水瘤细胞明显凋亡最小剂量是HPD(5 μg/ml)。结论 :ALA4 0mg/kg配合HPD2 .5mg/kg ,6 30半导体激光2 0 0mW /cm2 ,照射 2 0分钟是能达到小鼠S180腹水瘤细胞明显凋亡的最小光敏剂剂量。 相似文献
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光动力疗法对肝癌小鼠的抗肿瘤及免疫效应研究 总被引:15,自引:0,他引:15
目的探讨光动力疗法(PDT)对肿瘤组织杀伤作用及免疫效应的机理。方法应用PDT对40只接种H22肝癌的昆明小鼠作杀伤实验,对组织形态学、抑瘤率及免疫学指标进行检测。结果PDT对肿瘤细胞具有选择性杀伤和抑制肿瘤组织生长的作用,激光照射5天与对照组瘤重分别为(0.760±0.613)g,(1.951±0.822)g;肿瘤体积为(1.648±0.683)cm3,(3.976±0.847)cm3,t=5.856,8.973,P<0.01,两组差异有非常显著性。对正常组织无损伤。各免疫指标与对照组差异有显著性。结论PDT具有直接杀伤癌细胞、抑制肿瘤组织生长的作用,并且对荷瘤小鼠的免疫功能有调节作用。 相似文献
9.
Vladimir I. Bregadze Andrey A. Semioshkin Julia N. Las'kova Maria Ya. Berzina Irina A. Lobanova Igor B. Sivaev Mikhail A. Grin Rustam A. Titeev Dmitry I. Brittal Olga V. Ulybina Anastasija V. Chestnova Anastasija A. Ignatova Alexey V. Feofanov Andrey F. Mironov 《应用有机金属化学》2009,23(9):370-374
Conjugates of chlorin e6 with closo‐dodecaborate and cobalt bis(dicarbollide) anions were synthesized for the first time in high yields using the advanced ‘click’ methodology. In vitro study on A549 human lung adenocarcinoma cells revealed that the synthesized boronated conjugates are able to penetrate and accumulate in cancer cells, but their intracellular concentration is not sufficient for effective photodynamic and boron neutron capture therapy of cancer. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
10.
Hairong Li 《Tetrahedron letters》2008,49(33):4828-4830
The syntheses of two new A3B-type Zn(II)-phthalocyanines (Zn-Pcs) containing either one or two cobaltacarborane residues are reported, and the X-ray structure of a key phthalonitrile precursor is presented. The Zn-Pcs are highly soluble and exist as monomers in polar organic solvents. 相似文献