Murphy Bjerring (pyjamadecade65)

Purpose We recently developed a new fluorescence-based technique called "diffuse in vivo flow cytometry" (DiFC) for enumerating rare circulating tumor cells (CTCs) directly in the bloodstream. Non-specific tissue autofluorescence is a persistent problem, as it creates a background which may obscure signals from weakly-labeled CTCs. Here we investigated the use of upconverting nanoparticles (UCNPs) as a contrast agent for DiFC, which in principle could significantly reduce the autofluorescence background and allow more sensitive detection of rare CTCs. Methods We built a new UCNP-compatible DiFC instrument (U-DiFC), which uses a 980 nm laser and detects upconverted luminescence in the 520, 545 and 660 nm emission bands. We used NaYF4Yb,Er UCNPs and several covalent and non-covalent surface modification strategies to improve their biocompatibility and cell uptake. We tested U-DiFC with multiple myeloma (MM) and Lewis lung carcinoma (LLC) cells in tissue-mimicking optical flow phantoms and in nude mice. Results U-DiFC significantly reduced the background autofluorescence signals and motion artifacts from breathing in mice. Upconverted luminescence from NaYF4Yb,Er microparticles (UμNP) and cells co-incubated with UCNPs were readily detectable with U-DiFC in phantoms, and from UCNPs in circulation in mice. However, we were unable to achieve reliable labeling of CTCs with UCNPs. Our data suggest that most (or all) of the measured U-DIFC signal in vitro and in vivo likely arose from unbound UCNPs or due to the uptake by non-CTC blood cells. Conclusion UCNPs have a number of properties that make them attractive contrast agents for high-sensitivity detection of CTCs in the bloodstream with U-DiFC and other intravital imaging methods. More work is needed to achieve reliable and specific labeling of CTCs with UCNPs and verify long-term retention and viability of cells. selleck screening library © 2020 Bartosik et al.Introduction Cancer treatment using functionalized vehicles in order to block involved genes has attracted a remarkable interest. In this study, we investigated the cellular uptake and cytotoxic effects of three sizes of anti Bcl-2 DNAi-conjugated gold nanoparticles by MCF-7 cells. Methods Three different sizes of gold nanoparticles were synthesized by citrate reduction method and after characterization, the nanoparticles were functionalized by Bcl-2 targeted DNAi. Cell internalization of the nanoparticles was analyzed by atomic absorption spectroscopy and light microscopy. The cytotoxic effects of the nanoparticles were investigated by MTT assay, flow cytometry and RT-PCR of the target gene. Results While poor cell internalization of bare gold nanoparticles was observed, the results demonstrated that cellular uptake of DNAi-conjugated gold nanoparticles is completely size-dependent, and the largest nanoparticle (~42 nm) revealed the highest internalization rate compared to other sizes (~14 and ~26 nm). Experimental findings showed that the DNAi-conjugated gold nanoparticles induced apoptotic pathway by silencing of the targeted Bcl-2 gene. In addition, supplementary theoretical studies demonstrated that the 42 nm DNAi-conjugated gold nanoparticles have great photothermal conversion efficiency for treatment under external illumination and these nanoparticles can be induced further cytotoxic effect by approximately 10°C temperature elevations. Conclusion Remarkable photothermal properties of DNAi-conjugated 42 nm Au-NPs in parallel with their high cell internalization and cytotoxic effects introduce them as potential dual functional anticancer nanosystems. © 2020 Karimi et al.Background Breviscapine (BRE) has significant efficacy in cardiovascular disease, but the poor water solubility of breviscapine affects its oral absorption and limits its clinical application. In this study, supercritical carbon dioxide (SCF-CO2) technology was used to improve the solubility and bioavailability of BRE loaded into mesoporous silica nan