[Fucoidan-Modified Phase-Transitional Contrast Agent for Ultrasound Imaging and Targeting of Hepatoma Cells].

Objective: To prepare a fucoidan-modified phase-transitional contrast agent (FPCA) and to evaluate its in vitro capabilities for ultrasound imaging and targeting of hepatoma cells. Methods: Nano-liposomes encapsulated with perfluoropentane were prepared using thin-film hydration and ultrasonic emulsification methods. Then, FPCA nanoparticles were prepared through chemical grafting of fucoidan and the characterization of their physical and chemical properties was performed. After applying external stimuli of heating with hot water bath and microwave irradiation, the phase-transition status of FPCA was observed with microscope. The imaging abilities of phase-transited FPCA on two-dimensional ultrasound and contrast-enhanced ultrasound were observed with ultrasonic diagnostic instrument. The ability of FPCA to target at hepatoma cells was evaluated and verified with fluorescence confocal observation and flow cytometry analysis. Results: The FPCA prepared in the study had an average diameter of (222.1±32.5) nm, displaying spherical appearance, good dispersion, good stability, and good biocompatibility. The phase-transition of FPCA was induced by both heating with hot water bath and microwave irradiation. For phase transition, the optimal temperature was found to be 50 ℃ and the preferred microwave power was 1.5 W/cm 2. Moreover, after phase transition, FPCA showed significant imaging enhancement on both two-dimensional ultrasonography and contrast-enhanced ultrasonography. Through fluorescein isothiocyanate (FITC) labeling, FPCA could specifically bind with hepatoma cells at a high binding rate of (96.19±1.62)%, while it rarely bound with normal liver cells, showing a binding rate of less than 10%. Conclusion: A new type of phase-transitional ultrasound contrast agent with good stability and biocompatibility was successfully prepared. It not only could enhance ultrasound imaging through phase transition, but also had specific active hepatoma cell-targeting properties.

[Ultrasonic Manifestations of Desmoplastic Small Round Cell Tumor with Multiple Metastases: Case Report].

Desmoplastic small round cell tumor (DSRCT) is a rare malignant tumor, which is prone to occur in teenagers DSRCT is a rare malignant tumor that often occurs in adolescents. Early diagnosis is difficult and the prognosis is poor. In this case report, the ultrasonography of DSRCT showed that the huge solid mass was in the abdomen with unclear boundary, irregular shape, insufficient blood supply but without obvious liquefaction and calcification. The masses encircled the vessels, but no evidence of vascular invasion. Intrahepatic metastases with peripheral hypoechoic aureole and abdominal lymph node metastases were observed. The tumor mass compressed adjacent tissues and organs, causing bilateral hydronephrosis and bone erosion. In a word, the ultrasonographic characteristics could be used for diagnosing the DSRCT in the clinic.