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Objective To prepare multi-modality melanin-based lipid nanobubbles (MNBs) contrast agents,and to investigate their manifestations of ultrasound (US),photoacoustic (PA) and MRI in vitro.Methods MNBs and lipid nanobubbles (NBs) were prepared with the method of CHCl3-injection,freeze-drying and C3F8-inflation.The characteristics (shape,grain diameter,loading capacity of melanin and stability) of MNBs were obseved.US,PA and MRI were detected in vitro and the images were quantitatively analyzed.Results MNBs presented with homogenized size distribution,and transmission electron microscope (TEM) images demonstrated that the melanin particles were successfully entrapped into nanobubbles.Meanwhile,the loading capacity of melanin was 90.53 μg/mg.US signal increased in vitro with the rise of MNBs and NBs concentration.The ultrasonic manifestations of MNBs and NBs were the same,and the relative signal enhancement had no significant difference (P＞0.05).With the increased concentration of MNBs,the PA and MRI signals were stronger,but NBs showed no evident enhancement.Conclusion Multi-modality MNBs contrast agents are prepared successfully,which can enhance US,PA and MR imaging.
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Objective To prepare multi-modality melanin-based lipid nanobubbles (MNBs) contrast agents,and to investigate their manifestations of ultrasound (US),photoacoustic (PA) and MRI in vitro.Methods MNBs and lipid nanobubbles (NBs) were prepared with the method of CHCl3-injection,freeze-drying and C3F8-inflation.The characteristics (shape,grain diameter,loading capacity of melanin and stability) of MNBs were obseved.US,PA and MRI were detected in vitro and the images were quantitatively analyzed.Results MNBs presented with homogenized size distribution,and transmission electron microscope (TEM) images demonstrated that the melanin particles were successfully entrapped into nanobubbles.Meanwhile,the loading capacity of melanin was 90.53 μg/mg.US signal increased in vitro with the rise of MNBs and NBs concentration.The ultrasonic manifestations of MNBs and NBs were the same,and the relative signal enhancement had no significant difference (P＞0.05).With the increased concentration of MNBs,the PA and MRI signals were stronger,but NBs showed no evident enhancement.Conclusion Multi-modality MNBs contrast agents are prepared successfully,which can enhance US,PA and MR imaging.
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<p><b>OBJECTIVE</b>To investigate the effect of high-intensity focused ultrasound (HIFU) on tumor metastasis in mouse model bearing melanoma xenograft.</p><p><b>METHODS</b>Mice bearing murine melanoma B16-F10 cell xenograft were randomized for sham-HIFU or HIFU exposure when the tumors grew to a maximum diameter of 7-10 mm, and the tumor size was measured every 3 days. The cumulative survival rate of the mice and tumor metastasis rate were calculated, and the circulating melanoma cells were detected using qRT-PCR. At 14 days after HIFU treatment, B16-F10 cells were retransplanted via the tail vein and the pulmonary metastatic nodules were counted.</p><p><b>RESULTS</b>The median survival time of the mice was 19.00 days (95% CI 17.14-20.86 days) in the sham group and 26.00 days (95%CI 24.76-27.25 days) in HIFU group. The cumulative survival rate in the HIFU group was significantly higher than that in sham-HIFU group (P<0.01), and the tumor size was significantly smaller in HIFU group at 20, 23, and 26 days after HIFU treatment (P<0.05). Compared with the sham-HIFU group, HIFU group had significantly lower levels of MAGE-A3, MART1 and PAX3 at 7 days after HIFU (P<0.05) with still lower MAGE-A3 level at 14 days (P<0.05). HIFU group showed a significantly smaller number of pulmonary metastatic nodules following tumor cell retransplantation than in sham-HIFU group (P<0.01) with a metastasis inhibition rate of 42.4%.</p><p><b>CONCLUSION</b>HIFU treatment can inhibit tumor metastasis in melanoma-bearing mice possibly by reducing tumor cell detachment from the primary tumor site and suppressing colonization of the circulating melanoma cells.</p>
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Animals , Mice , High-Intensity Focused Ultrasound Ablation , Melanoma, Experimental , Therapeutics , Mice, Inbred C57BL , Neoplasm Metastasis , Survival RateABSTRACT
Objective To investigate the feasibility of enhancing therapeutic effects on goats' liver in vivo treated by high intensity focused ultrasound(HIFU)combined with microbubble contrast agent SonoVue.Methods Fifteen Nanjiang goats were adopted,own control was adopted in this study.One group received purely HIFU therapy(control group),another one was radiated with HIFU combined with SonoVue contrast agent(SonoVue group).The HIFU irradiating mode was dotted with 30 mm focal length and 150 W,250 W,350 W acoustic power respectively,and the exposure time was 15 s.Animals were sacrificed and dissected 24h later,and the sizes of necrotic region were measured.Specimens were collected for histological inspection.Results Under the same parameter of exposure,the maximum length,width,depth,and the mean volume of the tissue coagulated by HIFU in the SonoVue group were all significantly greater than those in control group(P＜0.05),the change of volume coagulated tissue was much more significant with the increase of the acoustic power.The energy effciency factor (EEF)of SonoVue group was significantly smaller than that of control group(P＜0.05).The demarcation line between the necrosis and normal region was clear and the necrosis was complete,no living cell.The boundary exist amount of bubbles.Conclusions The therapy of HIFU combined with microbubble eontrast agent can substantially enhance the biological effects of the treatment and improve the efficiency of HIFU therapy on goats liver.
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With the changes in the social structure of China, medical aid to the poor has become a hot issue in our society. The authors analyze the current state of medical aid to the poor in China, disenss the difficulties in providing medical aid to the poor at present, and put forward the idea of providing medical aid to the poor through specifying aid funds, conducting fundraising in every way, establishing foundations, adopting a variety of aid patterns, obtaining the active cooperation of local hospitals, and coordinating aid organizations.