No abstract

Nanomaterials have gained considerable attention and interest in the development of novel and high-resolution contrast agents for medical diagnosis and prognosis in clinic. A classical urea-based homogeneous precipitation route that combines the merits of in situ thermal decomposition and surface modification is introduced to construct polyethylene glycol molecule (PEG)-decorated hybrid lutetium oxide nanoparticles (PEG-UCNPs). By utilizing the admirable optical and magnetic properties of the yielded PEG-UCNPs, in vivo up-conversion luminescence and T1 -enhanced magnetic resonance imaging of small animals are conducted, revealing obvious signals after subcutaneous and intravenous injection, respectively. Due to the strong X-ray absorption and high atomic number of lanthanide elements, X-ray computed-tomography imaging based on PEG-UCNPs is then designed and carried out, achieving excellent imaging outcome in animal experiments. This is the first example of the usage of hybrid lutetium oxide nanoparticles as effective nanoprobes. Furthermore, biodistribution, clearance route, as well as long-term toxicity are investigated in detail after intravenous injection in a murine model, indicating the overall safety of PEG-UCNPs. Compared with previous lanthanide fluorides, our nanoprobes exhibit more advantages, such as facile construction process and nearly total excretion from the animal body within a month. Taken together, these results promise the use of PEG-UCNPs as a safe and efficient nanoparticulate contrast agent for potential application in multimodal imaging.

The purpose of this paper is to explore the possibilities of subcritical dimethyl ether extraction (SDME) of oil from tuna liver with high-moisture content.

Interstitial fluid pressure (IFP) in tumor tissue is significantly higher than that in normal tissue, which reduces the effectiveness of therapeutic drugs. There are several methods to decrease the IFP, such as normalizing blood vessel, decreasing hyaluronic acid and collagen fiber content in the extracellular matrix (ECM), and recovering lymphatic function. Reducing tumor IFP might be developed as a novel approach in cancer therapy. In this study, we aimed to elucidate the relationship between ultrasound combined with microbubble therapy and IFP, and the associated mechanism. VX2 tumor in rabbit was treated with ultrasound combined with microbubbles at different intensities. The IFP was measured using the wick-in-needle (WIN) method. The collagen and reticular fibers were stained by Masson and Gordon–Sweets, respectively. The results showed that low-frequency non-focus ultrasound combined with microbubbles therapy influences the IFP in tumor tissues; low-frequency non-focus ultrasound with low pressure increased the IFP, whereas middle–high pressure decreased the IFP. The results showed that the structure and content of collagen and reticular fibers in tumor tissue were rarely influenced by the treatment. Our study provides a novel approach of reduced IFP antitumor therapy.