Two-dimensional graphene and its composite nanomaterials offer interesting physical/chemical properties and have been extensively explored in a wide range of fields in recent years. In this work, we synthesize a multi-functional superparamagnetic graphene oxide-iron oxide hybrid nanocomposite (GO-IONP), which is then functionalized by a biocompatible polyethylene glycol (PEG) polymer to acquire high stability in physiological solutions. A chemotherapy drug, doxorubicin (DOX), was loaded onto GO-IONP-PEG, forming a GO-IONP-PEG-DOX complex, which enables magnetically targeted drug delivery. GO-IONP-PEG also exhibits strong optical absorbance from the visible to the near-infrared (NIR) region, and can be utilized for localized photothermal ablation of cancer cells guided by the magnetic field. Moreover, for the first time, in vivo magnetic resonance (MR) imaging of tumor-bearing mice is also demonstrated using GO-IONP-PEG as the T ₂ contrast agent. Our work suggests the promise of using multifunctional GO-based nanocomposites for applications in cancer theranostics. Open image in new window

Upconversion nanoparticles (UCNPs) have drawn much attention in cancer imaging and therapy in recent years. Herein, we for the first time report the use of UCNPs with carefully engineered surface chemistry for combined photodynamic therapy (PDT) and gene therapy of cancer. In our system, positively charged NaGdF₄:Yb,Er UCNPs with multilayered polymer coatings are synthesized via a layer by layer strategy, and then loaded simultaneously with Chlorin e6 (Ce6), a photosensitizing molecule, and small interfering RNA (siRNA), which targets the Plk1 oncogene. On the one hand, under excitation by a near-infrared (NIR) light at 980 nm, which shows greatly improved tissue penetration compared with visible light, cytotoxic singlet oxygen can be generated via resonance energy transfer from UCNPs to photosensitizer Ce6, while the residual upconversion luminescence is utilized for imaging. On the other hand, the silencing of Plk1 induced by siRNA delivered with UCNPs could induce significant cancer cell apoptosis. As the result of such combined photodynamic and gene therapy, a remarkably enhanced cancer cell killing effect is realized. Our work thus highlights the promise of UCNPs for imaging guided combination therapy of cancer.

A pneumonia associated with the coronavirus disease 2019 (COVID-19) recently emerged in China. It was recognized as a global health hazard. 234 inpatients with COVID-19 were included. Detailed clinical data, chest HRCT basic performances and certain signs were recorded Ground-glass opacity (GGO), consolidation, fibrosis and air trapping were quantified. Both clinical types and CT stages were evaluated. Most patients (approximately 90%) were classified as common type and with epidemiologic history. Fever and cough were main symptoms. Chest CT showed abnormal attenuation in bilateral multiple lung lobes, distributed in the lower and/or periphery of the lungs (94.98%), with multiple shapes. GGO and vascular enhancement sign were most frequent seen, followed by interlobular septal thickening and air bronchus sign as well as consolidation, fibrosis and air trapping. There were significant differences in most of CT signs between different stage groups. The SpO2 and OI were decreased in stage IV, and the CT score of consolidation, fibrosis and air trapping was significantly lower in stage I (P<0.05). A weak relevance was between the fibrosis score and the value of PaO2 and SpO2 (P<0.05). Clinical performances of patients with COVID-19, mostly with epidemiologic history and typical symptoms, were critical valuable in the diagnosis of the COVID-19. While chest HRCT provided the distribution, shape, attenuation and extent of lung lesions, as well as some typical CT signs of COVID-19 pneumonia.