Parameters of dual-energy CT for the differential diagnosis of thyroid nodules and the indirect prediction of lymph node metastasis in thyroid carcinoma: a retrospective diagnostic study.

Background: To further investigate the differential diagnosis of thyroid nodules using dual-energy computed tomography (DECT) and explore the relationship between DECT parameters and lymph node metastasis in thyroid carcinoma for clinical practice, especially difficult diagnosis by routine imaging examination. Methods: A total of 150 patients with thyroid nodules who underwent preoperative DECT and Thyroid Imaging Report and Data System (TIRADS) classification were enrolled in this study, including 96 patients with malignant tumors and 54 with benign tumors. The DECT parameters were got form regions of interest (ROI) by an experienced radiologist team and thyroid nodules and lymph node status of all patients were identified by cytology and histopathology. Statistical analyses were performed using Student's t-test, Chi-squared test, and receiver operating characteristic (ROC) curves. Results: In the differential diagnosis of benign and malignant thyroid nodules, the optimal iodine concentration (IC) and normalized iodine concentration (NIC) cut-off values were ICa (2.835 mg/mL), NIC1a (0.690), and their corresponding area under the curve (AUC) were 0.940, 0.954 respectively; meantime, the optimal computed tomography (CT) value and slope of the spectral Hounsfield unit curve (λHU) cut-off values were 70 keVa (125.05 HU) and λHU2a (1.405), and their corresponding AUC were 0.955, 0.941 respectively. For lymph node status (with or without lymph node metastasis), the optimal IC and NIC thresholds were ICa (1.715 mg/mL) and NIC2a (0.155), and their corresponding AUC were 0.717, 0.720 respectively; meanwhile, the optimal CT value and λHU thresholds were 70 keVv (89.635 HU) and λHU2v (1.185), and their corresponding AUC were 0.729, 0.641 respectively. Conclusions: Base on our study, we think DECT is useful in differentiating malignant from benign thyroid nodules, which has potential value in the indirect prediction of lymph node metastasis in thyroid carcinoma.

Trap-Assisted Charge Storage in Titania Nanocrystals toward Optoelectronic Nonvolatile Memory.

Transistor-based memories are of particular significance in the pursuit of next-generation nonvolatile memories. The charge storage medium in a transistor-based memory is pivotal to the device performance. In this report, nitrogen doping titania nanocrystals (N-TiO2 NCs) synthesized through a low-temperature nonhydrolytic method are used as the charge storage medium in a graphene transistor-based memory. The decoration of the N-TiO2 NCs enables the device to perform as an ultraviolet (UV) light-programmable nonvolatile optoelectronic memory. Multilevel nonvolatile information recording can be realized through accurate control of the incident light dose, which is ascribed to the vast and firm hole trapping abilities of the N-TiO2 NCs induced by the N dopant. Accordingly, a positive gate voltage can be used to erase the programmed state by promoting the recombination of stored holes in N-TiO2 NCs. This study manifests the importance of trap engineering for information storage and provides an alternative path toward nonvolatile optoelectronic memory.

Ampelopsin attenuates carbon tetrachloride-induced mouse liver fibrosis and hepatic stellate cell activation associated with the SIRT1/TGF-ß1/Smad3 and autophagy pathway.

Ampelopsin (Amp), a natural flavonoid found in the vine tea of Ampelopsis grossedentata, exhibited anti-cancer, anti-oxidant, anti-inflammatory, anti-apoptosis and hepatoprotective properties. The current study instigates the protective effect of Amp on carbon tetrachloride (CCl4)-induced hepatic fibrosis and explores its underlying mechanisms. The results indicated Amp decreased the levels of liver injury markers. Amp inhibited liver fibrosis, as indicated by decreases in hepatic collagen deposition, extracellular matrix (ECM) deposition and α-smooth muscle actin (α-SMA). Amp blocked the activation of hepaticstellate cells (HSCs) by decreasing the expression of collage I, α-SMA, tissue inhibitor of matrix metalloproteinases (TIMPs) 1, transforming growth factor (TGF)-ß1, phosphorylated Smad3 (p-Smad3) and increasing the expression of matrix metalloproteinases (MMPs) 9 and SIRT1 in the model of liver fibrosis and cultured HSCs. The sirtuin 1 (SIRT1) specific inhibitor Sirtinol activated the TGF-ß1/Smad3 pathway and enhanced ECM accumulation. Attractively, Amp up-regulates the expression of autophagy-related proteins microtubule-associated protein light chain three II (LC3-II) and Beclin-1 in vivo and in vitro. However, depletion of autophagy by specific inhibitor 3-MA obviously abolished the inhibiting effect of Amp on HSC activation and hepatic fibrosis. Conclusively, these results suggest that Amp could decrease CCl4-induced hepatic fibrosis through regulating the SIRT1/TGF-ß1/Smad3 and autophagy pathway.

Comparative optical study of colloidal anatase titania nanorods and atomically thin wires.

We present results of a comparative study of colloidal anatase titanium oxide nanorods and extremely thin atomic wires of systematically decreasing (2.6 nm down to 0.5 nm) diameter in terms of their optical absorption as well as steady-state and time-resolved photoluminescence. Steady-state photoluminescence spectra of the titania samples show three well-distinguished spectral components, which are ascribed to excitonic emission (4.26 ± 0.2 eV), as well as radiative recombination of trapped holes with electrons from the conduction band (4.04 ± 0.4 eV) and radiative recombination of trapped electrons with holes in the valence band (3.50 ± 0.2 eV) in nanocrystalline anatase TiO(2). Time-resolved photoluminescence measurements point out the existence of different emissive species responsible for the appearance of high-energetic and low-energetic emission peaks of TiO(2) atomic wires and nanorods.

From nanorods to atomically thin wires of anatase TiO(2): nonhydrolytic synthesis and characterization.

A nonhydrolytic two-step chemical process has been developed to synthesize ultrathin, nearly monodisperse TiO(2) (anatase) wires with tunable diameters of 5 nm to approximately 4 A, reaching the atomic length scale. The high-quality anatase titania atomically thin wires can be doped and stabilized with nitrogen species by introducing suitable nitrogen-containing molecules. The ultrathin wires, particularly the atomically thin wires, as well as the precursor, have been thoroughly characterized by an extensive series of structural, spectroscopic, and other techniques. Possible formation mechanisms for the rods and the wires are proposed on the basis of experimental results obtained under varying reaction conditions. Also demonstrated are the pronounced effects of size and N-doping on the electronic, optical, and phononic properties of the anatase titania wires in the smallest size regime.

Synthesis of angstrom-scale anatase titania atomic wires.

Using a nonhydrolytic solution approach, we demonstrate the bulk synthesis of extremely thin crystalline TiO2 atomic wires in the anatase phase with diameters reaching the atomic limit of a few angstroms (approximately 4-5 A). These nearly monodisperse, atomically thin, and soluble TiO2 wires fill a most important size gap in nanowire fabrication. Preliminary results on photocatalytic activity of the atomic wires are also presented on degradation of methylene blue under visible light. These atomic wires are expected to promote exchanges between theory and experiments in fundamental studies of a one-dimensional (1D) system and provide unique building blocks to construct high-performance devices.

Magnetic nanochains of metal formed by assembly of small nanoparticles.

Ni nanochains are synthesized with diameters of 150-250 nm and lengths of 0.5-2 microm by assembly of small nanoparticles, which exhibit a magnetic coercivity over two orders of magnitude larger than that of bulk Ni.

Large-scale synthesis of uniform nanotubes of a nickel complex by a solution chemical route.

Novel layer-rolled nanotubes of a nickel complex have been successfully synthesized by a simple wet chemical method. The nanotubes are assembled by rolling the (111) sheets of [Ni(NH3)6]Cl2 with the assistance of a polymer. The remarkable uniformity and high yields of the nickel complex nanotubes point to future applications in various fields of nanotechnology.