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91.
FPGA系统用于热疗方面的原理是利用物理能量加热人体全身或局部,使某些组织温度上升到有效治疗温度,并维持一定时间,利用正常组织和肿瘤细胞对温度耐受能力的差异,达到既能使肿瘤细胞凋亡、又不损伤正常组织的治疗目的。实验表明,在42℃区域,温度差1℃就可以引起细胞存活率的成倍变化。因此,热疗中能否准确测温和精确控制温度是取得疗效的关键。文章主要针对热疗系统的温度测控进行研究,设计一种基于FPGA用于热疗系统中的温度控制系统。通过程序控制来实现热疗过程中肿瘤组织温度的动态实时监测与高精度智能控制,以较高的温度控制精度来保证热疗的疗效。 相似文献
92.
Tao Jia Jiarui Du Jiani Yang Yang Li Tymish Y. Ohulchanskyy Xikui Fang Guanying Chen 《Advanced functional materials》2024,34(3):2307816
Noninvasive sonodynamic therapy (SDT) shows promise for brain glioma treatment due to deep tissue-penetrating capabilities (>10 cm) of ultrasound and high spatial resolutions. Yet, this technique is hindered by inefficient production of reactive oxygen species (ROS), resulting from the hypoxic tumor microenvironment (TME), high level of ROS scavenger glutathione (GSH), and the inability to visualize glioma in vivo for precise treatment management and monitoring in current sonosentizers. To address these challenges, we fabricated a core-shell heterostructure sonosensitizer (labeled as DFM), in which meso-tetra (4-carboxyphenyl) porphine (TCPP) porphyrin metal-organic frameworks (MOF, PCN-224(Fe)) serve as a porous shell to contain approved chemotherapeutics sorafenib (SRF) to effectively inhibit GSH synthesis, while NaErF4:Yb@NaLuF4 nanoparticles as the core provide TME-responsive NIR IIb (≈1500–1800 nm) luminescence at 1525 for precise optical imaging. Coordination of Fe3+ into the macrocycle of TCPP at the MOFs shell is found to, besides triggering ferroptosis, reduce TCPP phosphorescence (23% decrease) and increase the triplet state (T1) oxygen quenching, substantially promoting the singlet oxygen generation (2.6-fold increase). Furthermore, GSH in TME facilitates the reduction of Fe3+ to Fe2+, thereby eliminating the luminescence quenching of Fe3+ and augmenting the NIR IIb luminescence of Er3+ (5-fold increase) for nanoagents accumulation imaging in intracranial glioma, realizing dynamical monitoring of SDT processes. Compared to control groups, in vitro and in vivo experiments confirm the effective ROS generation and results in a 6-fold volume reduction of brain gliomas, reaching a survival rate of 80% at 30 days posttreatment. 相似文献
93.
Core–Satellite Mesoporous Silica–Gold Nanotheranostics for Biological Stimuli Triggered Multimodal Cancer Therapy 下载免费PDF全文
Ronghua Jin Zhongning Liu Yongkang Bai Yongsheng Zhou J. Justin Gooding Xin Chen 《Advanced functional materials》2018,28(31)
A core–satellite nanotheranostic agent with pH‐dependent photothermal properties, pH‐triggered drug release, and H2O2‐induced catalytic generation of radical medicine is fabricated to give a selective and effective tumor medicine with three modes of action. The nanocomplex (core–satellite mesoporous silica–gold nanocomposite) consists of amino‐group‐functionalized mesoporous silica nanoparticles (MSN‐NH2) linked to L‐cysteine‐derivatized gold nanoparticles (AuNPs‐Cys) with bridging ferrous iron (Fe2+) ions. The AuNPs‐Cys serve as both removable caps that control drug release (doxorubicin) and stimuli‐responsive agents for selective photothermal therapy. Drug release and photothermal therapy are initiated by the cleavage of Fe2+ coordination bonds at low pH and the spontaneous aggregation of the dissociated AuNPs‐Cys. In addition, the Fe2+ is able to catalyze the decomposition of hydrogen peroxide abundant in cancer cells by a Fenton‐like reaction to generate high‐concentration hydroxyl radicals (·OH), which then causes cell damage. This system requires two tumor microenvironment conditions (low pH and considerable amounts of H2O2) to trigger the three therapeutic actions. In vivo data from mouse models show that a tumor can be completely inhibited after two weeks of treatment with the combined chemo‐photothermal method; the data directly demonstrate the efficiency of the MSN–Fe–AuNPs for tumor therapy. 相似文献
94.
A Triple‐Collaborative Strategy for High‐Performance Tumor Therapy by Multifunctional Mesoporous Silica‐Coated Gold Nanorods 下载免费PDF全文
Guo‐Feng Luo Wei‐Hai Chen Qi Lei Wen‐Xiu Qiu Yu‐Xin Liu Yin‐Jia Cheng Xian‐Zheng Zhang 《Advanced functional materials》2016,26(24):4339-4350
To integrate treatments of photothermal therapy, photodynamic therapy (PDT), and chemotherapy, this study reports on a multifunctional nanocomposite based on mesoporous silica‐coated gold nanorod for high‐performance oncotherapy. Gold nanorod core is used as the hyperthermal agent and mesoporous silica shell is used as the reservoir of photosensitizer (Al(III) phthalocyanine chloride tetrasulfonic acid, AlPcS4). The mesoporous silica shell is modified with β‐cyclodextrin (β‐CD) gatekeeper via redox‐cleavable Pt(IV) complex for controlled drug release. Furthermore, tumor targeting ligand (lactobionic acid, LA) and long‐circulating poly(ethylene glycol) chain are introduced via host–guest interaction. It is found that the nanocomposite can specifically target to hepatoma cells by virtue of the LA targeting moiety. Due to the abundant existence of reducing agents within tumor cells, β‐CD can be removed by reducing the Pt(IV) complex to active cisplatin drug for chemotherapy, along with the releasing of entrapped AlPcS4 for effective PDT. As confirmed by in vitro and in vivo studies, the nanocomposite exhibits an obvious near‐infrared induced thermal effect, which significantly improves the PDT and chemotherapy efficiency, resulting in a superadditive therapeutic effect. This collaborative strategy paves the way toward high‐performance nanotherapeutics with a superior antitumor efficacy and much reduced side effects. 相似文献
95.
Treatment of Malignant Brain Tumor by Tumor‐Triggered Programmed Wormlike Micelles with Precise Targeting and Deep Penetration 下载免费PDF全文
Lijuan Zeng Lili Zou Haijun Yu Xinyu He Haiqiang Cao Zhiwen Zhang Qi Yin Pengcheng Zhang Wangwen Gu Lingli Chen Yaping Li 《Advanced functional materials》2016,26(23):4201-4212
The efficient and specific drug delivery to brain tumor is a crucial challenge for successful systemic chemotherapy. To overcome these limitations, here a tumor‐triggered programmed wormlike micelle is reported with precise targeting and deep penetration to treat malignant gliomas, which is composed of pH‐responsive mPEG‐b‐PDPA copolymer and bioreducible cyclic RGD peptide targeted cytotoxic emtansine (DM1) conjugates (RGD‐DM1). The RGD‐DM1 loaded nanoscaled wormlike micelles (RNW) exhibit nanometer‐sized wormlike assemblies with the transverse diameter of 21.3±1.8 nm and length within 60–600 nm, and the RGD targeting peptide in RNW is 4.2% in weight. RNW can be dissociated at intracellular acidic environments to release RGD‐DM1, and be further degraded into DM1 by cleavage of disulfide bonds in the reductive milieu. In particular, by exploiting the unique wormlike structure and the RGD targeting peptide modification, RNW can be endowed with obviously enhanced drug delivery to brain, precise targeting to brain tumor, deep penetration into tumor mass, and efficient internalization into glioma cells in a programmed manner, thereby surprisingly leading to an 88.9% inhibition on tumor progression in an orthotopic brain tumor model. Therefore, the properly designed RNW can provide a promising delivery platform for systemic chemotherapy of brain tumor. 相似文献
96.
97.
Tongxu Gu Yao Wang Yunhao Lu Liang Cheng Liangzhu Feng Hui Zhang Xiang Li Gaorong Han Zhuang Liu 《Advanced materials (Deerfield Beach, Fla.)》2019,31(14)
Electrochemical therapy (EChT), by inserting electrodes directly into tumors to kill cancer cells under direct current (DC), is clinically used in several countries. In EChT, the drastic pH variation nearby the inserted electrodes is the main cause of tumor damage. However, its limited effective area and complex electrode configuration have hindered the clinical application of EChT in treating diverse tumor types. Herein, a conceptually new electric cancer treatment approach is presented through an electro‐driven catalytic reaction with platinum nanoparticles (PtNPs) under a square‐wave alternating current (AC). The electric current triggers a reaction between water molecules and chloride ions on the surface of the PtNPs, generating cytotoxic hydroxyl radicals. Such a mechanism, called electrodynamic therapy (EDT), enables effective killing of cancer cells within the whole electric field, in contrast to EChT, which is limited to areas nearby electrodes. Remarkable tumor destruction efficacy is further demonstrated in this in vivo EDT treatment with PtNPs. Therefore, this study presents a new type of cancer therapy strategy with a tumor‐killing mechanism different from existing methods, using nanoparticles with electrocatalytic functions. This EDT method appears to be minimally invasive, and is able to offer homogeneous killing effects to the entire tumor with a relatively large size. 相似文献
98.
《Drug development and industrial pharmacy》2013,39(4):439-448
Background: As a promising anticancer drug, severe side-effects of current clinical formulations for paclitaxel have restricted its use, developing a better technical-economical formulation for paclitaxel delivery is needed. Method: In this study, the compound of folate-poly(ethylene glycol) (PEG)-phosphatidylethanolamine was synthesized and characterized with Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The solid-liquid lipid nanoparticle (SLLN) for paclitaxel modified with folate and poly(ethylene glycol) (folate-PEG-SLLN) was prepared and characterized. Morphology of folate-PEG-SLLN was examined by transmission electron microscopy. The particle size and zeta potential were performed by Zetapals. Encapsulation efficiency was analyzed by HPLC. The in vitro drug release of paclitaxel was investigated via membrane dialysis. The in vivo pharmacokinetics was measured with male Sprague-Dawley rats. Treatment efficiency was investigated with the mouse with sarcoma180 ascites tumor. Results: Paclitaxel loaded on the newly designed binary SLLN showed a longer and sustained in vitro releasing property. More importantly, S180 tumor-bearing mice treated with paclitaxel-loaded SLLN exhibited higher tumor inhibition rate, comparing with animals administered with paclitaxel injection alone (45.3% and 37.3%, respectively). Conclusion: The newly developed paclitaxel delivery system may have improved in vivo antitumor activity. The results demonstrated a great interest to use folate-mediated SLLN as a prospective drug delivery system for paclitaxel. 相似文献
99.
Photoacoustic Imaging: Perylene‐Diimide‐Based Nanoparticles as Highly Efficient Photoacoustic Agents for Deep Brain Tumor Imaging in Living Mice (Adv. Mater. 5/2015) 下载免费PDF全文
100.
Peptide Assembly Integration of Fibroblast‐Targeting and Cell‐Penetration Features for Enhanced Antitumor Drug Delivery 下载免费PDF全文