Ultrasound-based elastography: a novel approach to assess radio frequency ablation of liver masses performed with expandable ablation probes: a feasibility study

OBJECTIVE: The purpose of this study was to evaluate the technical feasibility of ultrasound-based elastography as a tool for assessing the size and shape of the coagulation necrosis caused by radio frequency ablation (RFA) probes using expandable electrodes ex vivo as well as in a patient with a liver metastasis. METHODS: A commercially available expandable RFA probe was used to create a 3-cm ablation in a piece of bovine liver. The ablation probe was used in situ to induce tissue deformation for elastography before and after ablation. Ultrasonic radio frequency data were processed to generate elasticity strain images. The appearance of the ablation zone was compared with magnetic resonance imaging and a gross section specimen. One patient with malignant metastatic disease to the liver and a clinical indication for RFA was investigated for the feasibility of percutaneous elastography of RFA using the same technique. Sonographic strain images were compared with the appearance of the nonenhancing ablation zone on contrast-enhanced computed tomography. RESULTS: Ex vivo, the ablation zone on ultrasound-based elastography was represented by an area of increased stiffness and was well demarcated from the nonablated surrounding tissue. The size and shape of the ablated zone on the strain image correlated well with the gross specimen and the magnetic resonance imaging appearance. Strain images obtained from the patient showed results similar to those of the ex vivo experiment and correlated well with the nonenhancing area of ablation on contrast-enhanced computed tomography. CONCLUSIONS: Ultrasound-based elastography may be a promising tool for displaying the ablation zone created by expandable RFA probes.     

决明子水提液微滤过程中膜通量和膜污染阻力的影响因素研究

目的探究陶瓷膜微滤决明子Cassia Semen水提液影响膜通量(J)和膜污染阻力(R_f)的因素。方法以决明子水提液为研究对象,在单因素试验的基础上,采用正交设计,以R_f和J的综合加权评分为评价指标,优化无机陶瓷膜微滤过程的最佳工艺参数;并对膜微滤过程中4个主要工艺参数与R_f和J的相关性进行分析。结果最佳膜微滤工艺条件:无机陶瓷膜孔径为0.2μm、料液质量浓度50.0 g/L、跨膜压差0.1 MPa、膜面流速3.32 m/s;微滤膜孔径对R_f和J的影响具有显著性。结论工艺条件对决明子水提液膜微滤过程中的J和R_f具有重要的影响;4种工艺参数对膜微滤过程R_f与J的影响主次顺序为膜孔径跨膜压差料液质量浓度膜面流速。     

Cancers in Australia attributable to exposure to solar ultraviolet radiation and prevented by regular sunscreen use

Objectives: To estimate the proportion and numbers of cancers occurring in Australia attributable to solar ultraviolet radiation (UVR) and the proportion and numbers prevented by regular sun protection factor (SPF) 15+ sunscreen use. Methods: We estimated the population attributable fraction (PAF) and numbers of melanomas and keratinocyte cancers (i.e. basal cell carcinomas and squamous cell carcinomas) due to exposure to ambient UVR resulting from residing in Australia versus residing in the UK (for melanoma) or Scandinavia (for keratinocyte cancers). We also estimated the prevented fraction (PF): the proportion of cancers that would have occurred but were likely prevented by regular sunscreen use. Results: An estimated 7,220 melanomas (PAF 63%) and essentially all keratinocyte cancers occurring in Australia were attributable to high ambient UVR levels in Australia. We estimated that regular sunscreen use prevented around 14,190 (PF 9.3%) and 1,730 (PF 14%) people from developing SCC and melanoma, respectively. Conclusions: Although our approach was conservative, a high proportion of skin cancers in Australia are attributable to high ambient levels of UVR. Prevailing levels of sunscreen use probably reduced skin cancer incidence by 10–15%. Implications: Most skin cancers are preventable. Sunscreen should be a component of a comprehensive sun protection strategy.     

母婴安全监护系统无线射频识别中间件设计与实现

目的:实现智能母婴安全监护系统中的无线射频识别(radio frequency identification,RFID)中间件的设计,以有效保障新生儿的健康和安全.方法:针对RFID数据的实时应用,设计实现一种包含服务层、逻辑层、数据层3层结构的轻量型RFID中间件,并将其应用于母婴安全监护系统的服务器中.结果:实现了RFID设备的实时通信与控制,可以有效地完成指令编码和对原始数据的解码.结论:利用该RFID中间件能够完成数据的准确读取与实时处理,其设计具有一定的鲁棒性和有效性,可以为RFID在医疗实时监测中的应用提供参考.     

局部晚期直肠癌新辅助调强放疗联合卡培他滨化疗67例疗效观察

[目的]评估局部晚期直肠癌新辅助调强放疗联合卡培他滨化疗安全性及疗效.[方法]对临床分期为T25/T4或淋巴结阳性的67例直肠腺癌患者进行新辅助调强放疗联合化疗.调强放疗方案为原发病灶及转移淋巴结外放1cm,放疗剂量55Gy,每次2.2Gy,盆腔放疗剂量为45Gy,每次1.8Gy.卡培他滨1650mg/(m2·d)分2次于放疗d1-14及d22～35口服,手术于放化疗结束后6～8周进行.[结果]除1例因3级腹泻停止放化疗外余均完成同步放化疗.同步放化疗不良反应:3级腹泻4例(6.0％),3级放射性皮炎3例(4.5％),无4级不良反应发生.术后15例(22.4％)达病理完全缓解.术后30d内无死亡病例,3例(4.5％)出现吻合口瘘,2例(3.0％)会阴部切口感染,1例(1.5％)出现肠梗阻.[结论]直肠癌新辅助调强放化疗安全,耐受性好,病理完全缓解率高.     

Preliminary evaluation of [18F]AlF-NOTA-MAL-Cys39-exendin-4 in insulinoma with PET

Background: High expression of glucagon-like peptide-1 receptor (GLP-1R) in insulinoma supplies a potential drug target for tumor imaging. Exendin-4 can specifically bind to GLP-1R as an agonist and its analogs are extensively used in receptor imaging studies.

Purpose: A new GLP-1R imaging agent, [¹⁸F]AlF-NOTA-MAL-Cys³⁹-exendin-4, was designed and prepared for insulinoma imaging.

Methods: Cys³⁹-exendin-4 was conjugated with NOTA-MAL, then the compound was radiolabeled with [¹⁸F]AlF complex to obtained [¹⁸F]AlF-NOTA-MAL-Cys³⁹-exendin-4. The tumor-targeting characters of the tracer were evaluated in INS-1 cells and BALB/c nude mice models.

Results: [¹⁸F]AlF-NOTA-MAL-Cys³⁹-exendin-4 can be efficiently produced with a yield of 17.5?±?3.2% (non-decay corrected) and radiochemical purity of >95%. The IC₅₀ value of displacement [¹⁸F]AlF-NOTA-MAL-Cys³⁹-exendin-4 with Cys³⁹-exendin-4 was 13.52?±?1.36?nM. PET images showed excellent tumor visualization with high uptake (9.15?±?1.6%ID/g at 30?min and 7.74?±?0.87%ID/g at 60?min). The tumor to muscle, pancreas and liver ratios were 63.25, 3.85 and 7.29 at 60?min after injection. GLP-1R binding specificity was demonstrated by co-injection with an excess of unlabeled Cys³⁹-exendin-4 and the tumor uptake was found to be reduced significantly.

Conclusion: [¹⁸F]AlF-NOTA-MAL-Cys³⁹-exendin-4 shows favorable characteristics for insulinoma imaging and may be translated to clinical studies.     

金属冠脉支架磁共振适用性检测方法

目的:建立金属冠脉支架磁共振适用性实验平台,以实验室测试为基础,研究金属冠脉支架的磁共振适用性。方法:金属冠脉支架磁共振适用性试验分为四个部分,在3T磁共振环境下,分别进行磁位移力试验、磁扭矩试验、致热试验和图像干扰试验。结果:退磁效果好的金属冠脉支架,磁位移力小于其自身重力,磁扭矩小于其自身重力扭矩,温度升高值小,图像畸变值小。退磁效果不好的支架,磁位移力大于其自身重力,温度升高多,图像畸变值大。结论:实验平台可以对金属冠脉支架磁共振适用性进行检测,并对其退磁效果进行评价。     

NMR‐based approach to the analysis of radiopharmaceuticals: radiochemical purity,specific activity,and radioactive concentration values by proton and tritium NMR spectroscopy

Compounds containing tritium are widely used across the drug discovery and development landscape. These materials are widely utilized because they can be efficiently synthesized and produced at high specific activity. Results from internally calibrated ³H and ¹H nuclear magnetic resonance (NMR) spectroscopy suggests that at least in some cases, this calibrated approach could supplement or potentially replace radio‐high‐performance liquid chromatography for radiochemical purity, dilution and scintillation counting for the measurement of radioactivity per volume, and liquid chromatography/mass spectrometry analysis for the determination of specific activity. In summary, the NMR‐derived values agreed with those from the standard approaches to within 1% to 9% for solution count and specific activity. Additionally, the NMR‐derived values for radiochemical purity deviated by less than 5%. A benefit of this method is that these values may be calculated at the same time that ³H NMR analysis provides the location and distribution of tritium atoms within the molecule. Presented and discussed here is the application of this method, advantages and disadvantages of the approach, and a rationale for utilizing internally calibrated ¹H and ³H NMR spectroscopy for specific activity, radioactive concentration, and radiochemical purity whenever acquiring ³H NMR for tritium location.     

Suppression of mTOR pathway and induction of autophagy-dependent cell death by cabergoline

Cabergoline (CAB), the first-line drug for treatment of prolactinomas, is effective in suppressing prolactin hypersecretion, reducing tumor size, and restoring gonadal function. However, mechanisms for CAB-mediated tumor shrinkage are largely unknown. Here we report a novel cytotoxic mechanism for CAB. CAB induced formation of autophagosome in rat pituitary tumor MMQ and GH3 cells at the early stage through inhibiting mTOR pathway, resulting in higher conversion rates of LC3-I to LC3-II, GFP-LC3 aggregation, and increased autophagosome formation. Interestingly, CAB treatment augmented lysosome acidification and resulted in impaired proteolytic degradation within autolysosomes. This blocked the autophagic flux, leading to the accumulation of p62 aggregation and undigested autolysosomes. Knockdown of ATG7, ATG5, or Becn1, could significantly rescue the CAB-mediated cell death of MMQ cells (p < 0.05). CAB-induced autophagy and blockade of autophagy flux participated in antitumoral action in vivo. In conclusion, our study provides evidence that CAB concomitantly induces autophagy and inhibits the autophagic flux, leading to autophagy-dependent cell death. These findings elucidate novel mechanisms for CAB action.