In vitro characterization and in vivo ultrasound molecular imaging of nucleolin-targeted microbubbles

Background. Contrast-enhanced ultrasound imaging has been widely used in the ultrasound diagnosis of a variety of tumours with high diagnostic accuracy, especially in patients with hepatic carcinoma, while its application is rarely reported in thyroid cancer. The currently used ultrasound contrast agents, microbubbles, cannot be targeted to molecular markers expressed in tumour cells due to their big size, leading to a big challenge for ultrasound molecular imaging. Phase-changeable perfluorocarbon nanoparticles may resolve the penetrability limitation of microbubbles and serve as a promising probe for ultrasound molecular imaging. Methods. 65 thyroid tumour samples and 40 normal samples adjacent to thyroid cancers were determined for SHP2 expression by IHC. SHP2-targeted PLGA nanoparticles (NPs-SHP2) encapsulating perfluoropentane (PFP) were prepared with PLGA-PEG as a shell material, and their specific target-binding ability was assessed in vitro and in vivo, and the effect on the enhancement of ultrasonic imaging induced by LIFU was studied in vivo. Results. In the present study, we verified that tumour overexpression of SHP2 and other protein tyrosine phosphatases regulated several cellular processes and contributed to tumorigenesis, which could be introduced to ultrasound molecular imaging for differentiating normal from malignant thyroid diagnostic nodes. The IHC test showed remarkably high expression of SHP2 in human thyroid carcinoma specimens. In thyroid tumour xenografts in mice, the imaging signal was significantly enhanced by SHP2-targeted nanoparticles after LIFU induction. Conclusion. This study provides a basis for preclinical exploration of ultrasound molecular imaging with NPs-SHP2 for clinical thyroid nodule detection to enhance diagnostic accuracy.

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Ultrasound molecular imaging of arterial thrombi with novel microbubbles modified by cyclic RGD in vitro and in vivo

Thrombosis and Haemostasis ◽

10.1160/th10-11-0701 ◽

2012 ◽

Vol 107 (01) ◽

pp. 172-183 ◽

Cited By ~ 21

Author(s):

Yulin Liao ◽

Li Yang ◽

Ruizhu Huang ◽

Juefei Wu ◽

Jiajia Xie ◽

...

Keyword(s):

Shear Stress ◽

Molecular Imaging ◽

Molecular Probe ◽

Great Promise ◽

Rgd Peptides ◽

Abdominal Aortic ◽

Aortic Thrombus ◽

Ultrasound Molecular Imaging

SummaryDespite immense potential, ultrasound molecular imaging (UMI) of arterial thrombi remains very challenging because the high-shear arterial flow limits binding of site-targeted microbubbles to the thrombi. The linear Arg-Gly-Asp (RGD) peptides have been successfully applied to evaluate venous, atrial, and arteriolar thrombi, but have thus far failed in the detection of arterial thrombi. Cyclic RGD (Arg-Gly-Asp-D-Phe-Cys) is a cyclic conformation of linear RGD peptides, which has much higher binding-affinity and selectivity for binding to the glycoprotein (GP) IIb/IIIa receptor than its linear counterpart and thus is likely to be an optimal targeted molecular probe for ultrasound molecular imaging of arterial thrombi. In this study, we sought to assess the feasibility of a novel microbubble conjugated with cyclic RGD (Mb-cyclic RGD) in UMI of arterial thrombi in vitro and in vivo. As expected, Mb-cyclic RGD had greater GP IIb/IIIa-targeted binding capability in all shear stress conditions. In addition, the shear stress at half-maximal detachment of Mb-cyclic RGD was 5.7-fold higher than that of microbubbles with nonspecific peptide (Mb-CON) (p<0.05). Mb-cyclic RGD enhanced the echogenicity of the platelet-rich thrombus in vitro whereas Mb-CON did not produce enhancement. In the in vivo setting, optimal signal enhancement of the abdominal aortic thrombus was displayed with Mb-cyclic RGD in all cases. Mean video intensity of the abdominal aortic thrombi with Mb-cyclic RGD was 3.2-fold higher than that with Mb-CON (p<0.05). The novel Mb-cyclic RGD facilitated excellent visualisation of arterial thrombi using UMI and showed great promise for clinical applications.

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Ultrasound Molecular Imaging of Atherosclerosis With Nanobodies

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvbaha.119.313088 ◽

2019 ◽

Vol 39 (12) ◽

pp. 2520-2530 ◽

Cited By ~ 8

Author(s):

Mukesh Punjabi ◽

Lifen Xu ◽

Amanda Ochoa-Espinosa ◽

Alexandra Kosareva ◽

Thomas Wolff ◽

...

Keyword(s):

Shear Stress ◽

Molecular Imaging ◽

Pulsatile Flow ◽

Ex Vivo ◽

Circulation Model ◽

Wild Type ◽

Double Knockout ◽

Ultrasound Molecular Imaging

Objective: Contrast-enhanced ultrasound molecular imaging (CEUMI) of endothelial expression of VCAM (vascular cell adhesion molecule)-1 could improve risk stratification for atherosclerosis. The microbubble contrast agents developed for preclinical studies are not suitable for clinical translation. Our aim was to characterize and validate a microbubble contrast agent using a clinically translatable single-variable domain immunoglobulin (nanobody) ligand. Approach and Results: Microbubble with a nanobody targeting VCAM-1 (MB cAbVcam1-5 ) and microbubble with a control nanobody (MB VHH2E7 ) were prepared and characterized in vitro. Attachment efficiency to VCAM-1 under continuous and pulsatile flow was investigated using activated murine endothelial cells. In vivo CEUMI of the aorta was performed in atherosclerotic double knockout and wild-type mice after injection of MB cAbVcam1-5 and MB VHH2E7 . Ex vivo CEUMI of human endarterectomy specimens was performed in a closed-loop circulation model. The surface density of the nanobody ligand was 3.5×10 5 per microbubble. Compared with MB VHH2E7 , MB cAbVcam1-5 showed increased attachment under continuous flow with increasing shear stress of 1-8 dynes/cm 2 while under pulsatile flow attachment occurred at higher shear stress. CEUMI in double knockout mice showed signal enhancement for MB cAbVcam1-5 in early ( P =0.0003 versus MB VHH2E7 ) and late atherosclerosis ( P =0.007 versus MB VHH2E7 ); in wild-type mice, there were no differences between MB cAbVcam1-5 and MB VHH2E7 . CEUMI in human endarterectomy specimens showed a 100% increase in signal for MB cAbVcam1-5 versus MB VHH2E7 (20.6±27.7 versus 9.6±14.7, P =0.0156). Conclusions: CEUMI of the expression of VCAM-1 is feasible in murine models of atherosclerosis and on human tissue using a clinically translatable microbubble bearing a VCAM-1 targeted nanobody.

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In vivo and in vitro characterization of immediate release dosage forms containing n-acetylcysteine using the dynamic open flow-through test apparatus

10.26226/morressier.57d6b2b7d462b8028d88dd29 ◽

2016 ◽

Author(s):

Maximilian Sager

Keyword(s):

Immediate Release ◽

Dosage Forms ◽

Test Apparatus ◽

Open Flow ◽

In Vitro Characterization ◽

Flow Through

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THE ROLE OF POLYETHYLENIMINE IN ENHANCING PERFORMANCE OF GLUTAMATE BIOSENSORS

Journal of Medicine and Pharmacy ◽

10.34071/jmp.2018.3.6 ◽

2018 ◽

Vol 8 (3) ◽

pp. 36-41

Author(s):

Diep Do Thi Hong ◽

Duong Le Phuoc ◽

Hoai Nguyen Thi ◽

Serra Pier Andrea ◽

Rocchitta Gaia

Keyword(s):

First Generation ◽

Good Reproducibility ◽

Complex Matrices ◽

Long Term Stability ◽

In Vitro Characterization ◽

Glutamate Oxidase

Background: The first biosensor was constructed more than fifty years ago. It was composed of the biorecognition element and transducer. The first-generation enzyme biosensors play important role in monitoring neurotransmitter and determine small quantities of substances in complex matrices of the samples Glutamate is important biochemicals involved in energetic metabolism and neurotransmission. Therefore, biosensors requires the development a new approach exhibiting high sensibility, good reproducibility and longterm stability. The first-generation enzyme biosensors play important role in monitoring neurotransmitter and determine small quantities of substances in complex matrices of the samples. The aims of this work: To find out which concentration of polyethylenimine (PEI) exhibiting the most high sensibility, good reproducibility and long-term stability. Methods: We designed and developed glutamate biosensor using different concentration of PEI ranging from 0% to 5% at Day 1 and Day 8. Results: After Glutamate biosensors in-vitro characterization, several PEI concentrations, ranging from 0.5% to 1% seem to be the best in terms of VMAX, the KM; while PEI content ranging from 0.5% to 1% resulted stable, PEI 1% displayed an excellent stability. Conclusions: In the result, PEI 1% perfomed high sensibility, good stability and blocking interference. Furthermore, we expect to develop and characterize an implantable biosensor capable of detecting glutamate, glucose in vivo. Key words: Glutamate biosensors, PEi (Polyethylenimine) enhances glutamate oxidase, glutamate oxidase biosensors

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