靶向抗肿瘤纳米粒用于增强声动力/饥饿联合治疗

目的 制备一种载IR780及葡萄糖氧化酶(GOx)的多功能纳米粒,研究其主动靶向能力,并评估其体外光声成像及声动力(sonodynamic therapy, SDT)/饥饿联合治疗的效果。方法 通过双乳化法制备载有IR780及GOx的聚乳酸-羟基乙酸共聚物(poly (lactic-co-glycolic) acid, PLGA)纳米粒(IG@P 纳米粒) 。检测IG@P 纳米粒的理化特性,观察其体外光声成像的效果,并评估该纳米粒对肿瘤细胞的靶向能力及体外联合治疗效果。结果 制备的IG@P纳米粒呈大小均一的球形,平均粒径(248.1 ± 24.3) nm,且仍保留GOx的酶催化活性。实验结果表明IG@P纳米粒具有良好的光声成像及主动靶向效果。与单一治疗相比,SDT及饥饿治疗联合治疗可以更明显杀伤乳腺癌4T1细胞。且IR780的主动靶向作用,促进纳米粒在肿瘤细胞内的聚集,显著提高了SDT/饥饿治疗的治疗效果。结论 成功制备了具有肿瘤靶向作用的IG@P多功能纳米粒,可用于光声成像,并可增效SDT/饥饿联合治疗。     

Sonodynamic Action of Pyropheophorbide‐a Methyl Ester in Liver Cancer Cells

Objective. This study aimed to investigate the sonodynamic action of pyropheophorbide‐a methyl ester (MPPa) in liver cancer cells to explore a novel therapeutic modality. Methods. H22 cells were chosen as model cells to investigate the sonodynamic action of MPPa on liver cancer. The MPPa concentration was kept constant at 2 μmol/L, and the cells were subjected to ultrasound exposure at an intensity of 0.97 W/cm². Cytotoxicity was investigated 24 hours after ultrasound exposure. Apoptosis was evaluated using flow cytometry with annexin V‐fluorescein isothiocyanate and propidium iodine staining and nuclear staining with Hoechst 33258. Reactive oxygen species (ROS) were analyzed using flow cytometry with 2,7‐dichlorodihydrofluorescein diacetate staining. Results. No significant dark cytotoxicity of MPPa was shown in the H22 cells at the concentration of 2 μmol/L. The cell death rate induced by ultrasound treatment was significantly higher in the presence of MPPa than in the absence of it (P < .05). Flow cytometry showed that the sonodynamic action of MPPa significantly increased the early and late apoptotic rates of the H22 cells. Nuclear condensation and an ROS increase were found after sonodynamic treatment. Conclusions. Our findings showed that MPPa‐mediated sonodynamic action significantly enhanced death of H22 cells and the ROS level, suggesting that MPPa is a novel sonosensitizer and the sonodynamic action of MPPa might be a potential therapeutic modality in the management of liver cancer.     

相变型载药纳米粒用于肿瘤的多模态显像与声动力治疗联合化疗的体外实验研究

目的 制备载全氟戊烷/锰卟啉/紫杉醇的多功能纳米探针,评估其体外光声/超声/磁共振三模态成像及声动力治疗(SDT)联合化疗的效果。方法 采用双乳化法制备载全氟戊烷(PFP)/锰卟啉(MnTTP)/紫杉醇(PTX)的聚乳酸-羟基乙醇酸(PLGA)纳米粒(PFP-MnTTP-PTX@PLGA,FMP@P),检测其表面电位、平均粒径、药物包封率,并在透射电镜及扫描电镜下观察其形态。观察纳米粒的体外光声/超声/磁共振显像效果及活性氧产生能力。通过CCK-8法及流式细胞术验证FMP@P体外SDT联合化疗杀伤肿瘤细胞的效果。结果 FMP@P平均粒径为(323.1 ± 68.3)nm,表面电位为(-14.5 ± 8.3)mV,MnTTP及PTX包封率分别为93.55 ± 0.46%、81.23 ± 6.93%。纳米粒可以增强超声/光声/磁共振成像。经超声辐照后,4T1细胞内产生大量活性氧,可显著杀伤肿瘤细胞。结论 本研究成功制备了载全氟戊烷/锰卟啉/紫杉醇的多功能纳米粒,可体外增强光声/超声/磁共振显像,并介导SDT联合化学治疗。     

Ultrasound Dose Fractionation in Sonodynamic Therapy

Sonodynamic therapy (SDT) is a new modality in cancer therapy and it is based on preferential uptake and/or retention of a sonosensitizing drug in tumor tissues and subsequent activation of the drug by ultrasound. The dose fractionation effect in radiation therapy has been known for more than a century, but it is not reported in SDT so far. In this study, the in vivo antitumor effect of the simultaneous dual-frequency ultrasound (1 MHz and 150 kHz) at low-level intensity (cumulative I_SATA = 2.2W/cm²; total energy density 3960J/cm²; for 30 min sonication) in combination with the sonosensitizer of photofrin (PF) (sodium porfimer) was investigated in dose fractionation regime in a spontaneous murine model of breast adenocarcinoma in Balb/c mice. The tumor-bearing mice were divided into six groups (n = 8 to 10): Untreated groups included control and sham; experimental groups were treated with 5 mg/kg intravenous injection of PF alone, with combined PF and ultrasound for 30-min sonication in one fraction at 24 h after PF administration; with combined PF and ultrasound for 30 min sonicatin in three fraction at 18, 24 and 30 h after PF administration; and finally with combined PF and ultrasound for 30 min sonication in five fraction at 12, 18, 24, 30 and 36 h after PF administration. The tumor growth delay (TGD) parameters and the percent of apoptotic index AI (%) were measured in treated and untreated groups. The results show that the TGD parameters in treatment groups with combined drug and ultrasound fractionation mode were significantly different compared with other groups (p < 0.05). Also the sonodynamic ultrasound dose fractionation in five fractions is more effective than of the three-fraction regime. The AI of the tumor tissues treated by ultrasound dose fractionation was also significantly higher in the other groups (p < 0.05), in which the AI (%) in the group treated with five fractions was higher with respect to group treated with 3 fractions (11.56 ± 1.2; 8.7 ± 0.87), respectively. In conclusion, the ultrasound dose fractionation can be useful in therapeutic effect in SDT and may have future clinical applications. (E-mail: ah_barati@yahoo.com)     

Blocking the Glycolytic Pathway Sensitizes Breast Cancer to Sonodynamic Therapy

Inhibition of the increased aerobic glycolysis in cancer cells is a promising methodology for various malignant tumor therapies but is limited by systemic toxicity, at least in part. Recent studies suggest that dual restriction of glycolysis and mitochondrial function may overcome this issue. Sonodynamic therapy (SDT), a prospective therapeutic modality for cancers, has been reported to induce mitochondria-dependent cell damage. Here, we investigated the combined effect of SDT and 2-deoxyglucose (2DG), an anti-glycolytic agent, on breast cancer both in vitro and in vivo. In vitro, we found that, compared with a single treatment, SDT + 2DG co-treatment significantly decreased cell viability and increased cell apoptosis. Moreover, the generation of reactive oxygen species was enhanced and mitochondrial membrane potential (MMP) was reduced after SDT + 2DG co-treatment. Furthermore, the oxidative phosphorylation was also restrained after SDT + 2DG co-treatment, further to cause the blockage of ATP provision. In vivo, SDT + 2DG markedly reduced tumor volume and weight, consistent with the in vitro findings. Furthermore, toxicology tests concurrently indicated that the dosages of sinoporphyrin sodium and 2DG were comparatively tolerable. Generally, these results indicated that SDT + 2DG combination therapy may be an available, promising therapy for highly metastatic breast cancer.     

Sonodynamic Therapy Based on Combined Use of Low Dose Administration of Epirubicin-Incorporating Drug Delivery System and Focused Ultrasound

Sonodynamic therapy (SDT) is currently considered as one of the promising minimally invasive treatment options for solid cancers. SDT is based on the combined use of a sonosensitizer drug and high-intensity focused ultrasound (HIFU) to produce cytotoxic reactive oxygen species (ROS) in and around neoplastic cells. Anthracycline drugs, including epirubicin (EPI), have been well known as effective sonosensitizers after interaction with focused ultrasound. Recently a new anticancer drug delivery system (DDS), NC-6300, has been developed that comprises EPI through an acid–labile hydrazone bond. In previous in vivo studies, NC-6300 showed basic drug safety and an excellent concentration property of EPI, and recently has been tested in clinical trials. For realizing minimally invasive cancer treatment, the present study demonstrated the effectiveness and feasibility of DDS-based SDT, which combined a small dose of NC-6300 and low energy of HIFU in mouse models of colon cancer and pancreatic cancer.     

Personalized Cancer Vaccines: Clinical Landscape,Challenges, and Opportunities

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Sonodynamic Therapy for Malignant Glioma Using 220-kHz Transcranial Magnetic Resonance Imaging-Guided Focused Ultrasound and 5-Aminolevulinic acid

Sonodynamic therapy (SDT) is used to treat various malignancies and can be applied to brain tumors using a transcranial magnetic resonance imaging-guided focused ultrasound (TcMRgFUS) device. This study investigated the efficacy of 220-kHz TcMRgFUS combined with 5-aminolevulinic acid (5-ALA) on malignant glioma in vitro and in vivo. F98 cells were irradiated with focused ultrasound (FUS) (4000 J, 20 W, 240 s, 100% duty cycle, target medium temperature <40°C) after treatment with 200 µg/mL 5-ALA, and cell viability and apoptosis were evaluated with the water-soluble tetrazolium-1 assay, triple fluorescent staining and Western blot analysis 20 h later. The anti-tumor effects of 5-ALA combined with FUS (500 J, 18 W, 30 s, 100% duty cycle, 10 repeats, target tissue temperature ≤42°C) were assessed on the basis of changes in tumor volume determined by MRI and histopathological analysis before and after treatment. The FUS/5-ALA combination reduced cell viability by inducing apoptosis and suppressed tumor proliferation and invasion as well as angiogenesis in vivo, while causing minimal damage to normal brain tissue. SDT with 220-kHz TcMRgFUS and 5-ALA can be safely used for the treatment of malignant glioma.     

Involvement of caspase 8 in apoptosis induced by ultrasound-activated hematoporphyrin in sarcoma 180 cells in vitro.

OBJECTIVE: Sonodynamic therapy (SDT), a novel and promising cancer therapy that uses a combination of ultrasound and hematoporphyrin, can induce apoptosis in some cancer cells. However, the mechanism(s) of SDT-induced cell apoptosis is not well understood. This study investigated SDT-induced apoptosis in sarcoma 180 cells. METHODS: Cell suspension were treated by 1.75-MHz continuous focused ultrasound in the presence of hematoporphyrin for 3 minutes, and apoptosis was assessed by flow cytometry, scanning electron microscopy, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling, confocal microscopy, and apoptosis-related protein analysis. RESULTS: DNA breaks, apoptotic bodies, and cleaved poly (adenosine triphosphate-ribose) polymerase were observed 1 hour after SDT. By using laser-scanning confocal microscopy, we found that the Fas-associated death domain and caspase 8 translocated from the cytoplasm to the plasma membrane. Activities of caspase 8 and caspase 3 were detected by an immunohistochemical assay. The results suggested that SDT led to activation of caspase 8, which in turn activated downstream caspase 3. In addition, Z-Ile-Glu-Thr-Asp-fluoromethylketone, a specific inhibitor for caspase 8, was used to confirm the effect of caspase 8 in apoptosis. CONCLUSIONS: Our data primarily show that SDT can induce apoptosis in sarcoma 180 cells in vitro, and caspase 8 may play an important role in SDT-induced apoptosis.     

循证医学在康复治疗技术专业临床实习中的应用

目的探讨循证医学在康复治疗技术专业临床实习中的应用效果。方法选择2011 年7 月~2012 年4 月实习生(对照组,n=23)采用传统带教方法, 2012 年7 月~2013 年4 月实习生(试验组,n=22)在传统带教方法基础上结合循证医学思维模式,采用理论及操作考试成绩、调查问卷进行评价。结果试验组的操作技术考试成绩及总成绩高于对照组(P<0.05)。试验组的提高自学能力、发挥主观能动性、培养临床思维、提高信息获得能力、提高选择文献资料的能力、提高分析归纳能力、提高自身整体水平、对此教学方法的满意度8 个方面优于对照组(P<0.05)。结论康复治疗技术专业学生在临床实习中应用循证医学思维模式,有利于提高学生的实践操作技能,更好地培养学生的临床思维,提高学生自身整体水平。     

Treatment of Murine Tumors Using Dual-Frequency Ultrasound in an Experimental in Vivo Model

Acoustic inertia cavitation is the primary mechanism underlying sonochemical reactions and has potential for use in tumor treatment. In in vitro experiments that were performed previously and are thus not included in this paper, we found that the ultrasonically-induced chemical reactions are greatly accelerated when ultrasound is simultaneously applied at frequencies of 1 MHz and 150 kHz.. In this study, the in vivo anti-tumor effect of the simultaneous dual-frequency ultrasound at low level intensity (I_SPTA <6 W/cm²) was investigated in a murine model of breast adenocarcinoma in Balb/c mice. The tumor-bearing mice were divided into five groups: those treated with combined dual-frequency ultrasound in continuous mode (1 MHz_con+150 kH_zcon) for 30 and 15 min (C and D), those treated with dual-frequency ultrasound in which the source of 1 MHz was in pulse mode (duty cycle of 80%) and that of 150 kHz was in continuous mode for 30 min (E), and untreated control and sham groups (A and B). The tumor growth parameters evaluated to assess delay include tumor volume, relative tumor volume, and T₅ and T₂, which are the time needed for each tumor to reach 5 and 2 times its initial volume, respectively. The survival period and percent of tumor growth inhibition ratio and were measured at various times after treatment. The results show that treatment with a combined continuous mode of 1 MHz_con+150 kHz_con and a pulse mode of 1 MHz_pl,80%+150 kHz_con effectively delayed tumor growth and increased the tumor growth inhibitory ratio compared to the sham group. When the tumor volume growth and relative volume of tumors in treated groups C, D and E were examined, an anti-tumor effect was observed in groups E and C. There is a significant difference between groups E and C and the sham group 12 d after treatment for tumor volume growth and 18 d after treatment for relative tumor volume (p < 0.05). The mean survival periods for animals in groups C and E were 16% and 17% more than the control group. T₅ and T₂ (in days) of groups E, C and B are 19.1 ± 0.4 and 7.6 ± 1.5, 17.2 ± 0.6 and 6.3 ± 2.1, 14.3 ± 1.1 and 5.1 ± 2.5 d, respectively. There was a significant difference between groups C and E and the sham group (B) for T₅ (p < 0.05), but for T₂, there was no significant difference between groups (p > 0.05). The tumor growth inhibition ratio in groups C, D and E was 23, 20 and 37% of that in group B, and those differences are statistically significant (p <0.05). It is concluded that sonodynamic therapy with combined dual–frequency ultrasound in a progressive wave mode can be useful for cancer therapy.     

Histotripsy: The Next Generation of High-Intensity Focused Ultrasound for Focal Prostate Cancer Therapy

This article reviews the most current methods and technological aspects of high-intensity focused ultrasound (HIFU), which is termed histotripsy. The rationale for focal therapy for prostate carcinoma rather than prostatectomy, which is being used extensively throughout Europe and Asia, is presented, and an argument for why HIFU is the modality of choice for primary therapy and recurrent disease is offered. The article presents a review of the technical advances including higher ultrasound beam energy than current thermal HIFU which allows for more accurate tissue targeting, less collateral tissue damage, and faster treatment times. Finally, the article presents a discussion about the advantage of ultrasound guidance for histotripsy in preference to magnetic resonance imaging guidance primarily based on cost, ease of application, and portability.     

Sonodynamically Induced Antitumor Effects of 5-Aminolevulinic Acid and Fractionated Ultrasound Irradiation in an Orthotopic Rat Glioma Model

The sonodynamically induced selective antitumor effects of 5-aminolevulinic acid (5-ALA) on a C6 glioma that was implanted in a rat brain were evaluated. One week after the inoculation of the brains with the C6 rat glioma cells, glioma development was monitored using a 1.5 T MRI. Brains both with and without intravenous administration of 5-ALA (60 mg/kg body weight) or Radachlorin (40 mg/kg body weight) were insonated by a 1 MHz ultrasound at a dose of 2.65 W/cm². Irradiation was performed in a fractionated manner to avoid any thermal effects in the tissue due to the focused ultrasound; 16 min of irradiation were followed by a 3 min recess, then 4 min of resumed irradiation. Mean tumor sizes, measured after the rats were sacrificed 2 weeks post treatment, were 122.48 ± 39.64 mm³ in sham-operated rats, 87.42 ± 21.40 mm³ in rats receiving ultrasound without 5-ALA, 10.50 ± 8.20 mm³ in rats receiving ultrasound with 5-ALA, and 56.42 ± 12.48 mm³ in rats receiving ultrasound with Radachlorin. The tumor size was significantly smaller in the therapy group receiving sonodynamic 5-ALA than in any of the other groups (p < 0.05). This experimental rat model showed that sonodynamic therapy can be useful in the treatment of deep-seated malignant gliomas.     

临床实用模式在康复治疗学专业本科教学中的应用

目的探讨美国物理治疗师学会的临床实用模式在康复治疗学专业本科教学的应用效果。方法选择2007级1班、2008级2班康复治疗专业本科三、四年级学生专业理论课与实践课,2007级采用传统教学结合30%的以问题为基础的学习,2008级2班采用美国物理治疗师学会的临床实用模式。结果和结论 2008级在整体医疗规范把握能力方面显著好于2007级(P<0.001),在功能评估、治疗实施、结果评价、出院后指导和预防措施方面好于2007级(P<0.05)。     

乳癌保乳手术适应证的探讨

目的：探讨乳腺癌保乳手术的合理适应证。方法：回顾性分析104例乳腺癌保乳手术患者的年龄、肿瘤大小、肿瘤部位、腋淋巴结状态、临床分期、病理类型等因素在保乳手术决策中的价值。结果：本组患者100例得到随访，失访4例，随访率96．4％；随访时间1～56个月，中位随访时间42个月。其中1例于手术后26个月发现原发性子宫内膜癌，49个月后死亡；1例12个月后同侧腋窝复发改行改良根治术；1例发现同侧锁骨上淋巴结转移行放疗；1例发现对侧原发性乳房癌行根治性手术(原保乳侧为导管浸润癌，对侧再发为导管内癌)；1例患乳再发纤维腺瘤而做局部切除术。结论：保乳手术将逐渐成为I、II期乳腺癌患者的主流手术，甚至部分IIIA期患者在新辅助化疗后可以获得保乳机会，保乳手术的适应证有扩大的趋势。     

Bridging the Gap between Clinical Research and Knowledge Translation in Pediatric Emergency Medicine

In 2006, a multidisciplinary group of researchers from across Canada submitted a successful application to the Canadian Institutes for Health Research for a Canadian Institutes for Health Research Team in Pediatric Emergency Medicine. The conceptual foundation for the proposal was to bring together two areas deemed critical for optimizing health outcomes: clinical research and knowledge translation (KT). The framework for the proposed work is an iterative figure-eight model that provides logical steps for research and a seamless flow between the development and evaluation of therapeutic interventions (clinical research) and the implementation and uptake of those interventions that prove to be effective (KT). Under the team grant, we will conduct seven distinct projects relating to the two most common medical problems affecting children in the emergency department: respiratory illness and injury. The projects span the research continuum, with some projects targeting problems for which there is little evidence, while other projects involve problems with a strong evidence base but require further work in the KT realm. In this article, we describe the history of the research team, the research framework, the individual research projects, and the structure of the team, including coordination and administration. We also highlight some of the many advantages of bringing this research program together under the umbrella of a team grant, including opportunities for cross-fertilization of ideas, collaboration among multiple disciplines and centers, training of students and junior researchers, and advancing a methodological research agenda.     

Implementing Early Goal-directed Therapy in the Emergency Setting: The Challenges and Experiences of Translating Research Innovations into Clinical Reality in Academic and Community Settings

Research knowledge translation into clinical practice pathways is a complex process that is often time-consuming and resource-intensive. Recent evidence suggests that the use of early goal-directed therapy (EGDT) in the emergency department care of patients with severe sepsis and septic shock results in a substantial mortality benefit; however, EGDT is a time- and resource-intensive intervention. The feasibility with which institutions may translate EGDT from a research protocol into routine clinical care, among settings with varying resources, staff, and training, is largely unknown. The authors report the individual experiences of EGDT protocol development, as well as preimplementation and postimplementation experiences, at three institutions with different emergency department, intensive care unit, and hospital organization schemes.