Although biomedical applications of carbon nanotubes have been intensively studied in recent years, its sister, graphene, has been rarely explored in biomedicine. In this work, for the first time we study the in vivo behaviors of nanographene sheets (NGS) with polyethylene glycol (PEG) coating by a fluorescent labeling method. In vivo fluorescence imaging reveals surprisingly high tumor uptake of NGS in several xenograft tumor mouse models. Distinctive from PEGylated carbon nanotubes, PEGylated NGS shows several interesting in vivo behaviors including highly efficient tumor passive targeting and relatively low retention in reticuloendothelial systems. We then utilize the strong optical absorbance of NGS in the near-infrared (NIR) region for in vivo photothermal therapy, achieving ultraefficient tumor ablation after intravenous administration of NGS and low-power NIR laser irradiation on the tumor. Furthermore, no obvious side effect of PEGylated NGS is noted for the injected mice by histology, blood chemistry, and complete blood panel analysis in our pilot toxicity study. Although a lot more efforts are required to further understand the in vivo behaviors and the long-term toxicology of this new type of nanomaterials, our work is the first success of using carbon nanomaterials for efficient in vivo photothermal therapy by intravenous administration and suggests the great promise of graphene in biomedical applications, such as cancer treatment.

Departmental sources Background:At the end of 2019, the COVID-19 outbreak began in Wuhan, Hubei, China, and spread rapidly to the whole country within 1 month. This new epidemic caused a great mental reaction among the public. This study aimed to assess and compare the prevalence and associated factors of anxiety and depression among the public affected by quarantine and those unaffected during the COVID-19 outbreak in southwestern China in early Feb. 2020. Material/Methods:Data were collected using the self-rating anxiety scale (SAS) and the self-rating depression scale (SDS) administered to 1593 respondents aged 18 years and above. The respondents were grouped as 'affected group' and 'unaffected group' on the basis of whether they or their families/colleagues/classmates/neighbors had been quarantined. Results:Among 1593 participants, the prevalence of anxiety and depression was approximately 8.3% and 14.6%, respectively, and the prevalence in the affected group (12.9%, 22.4%) was significantly higher than that in the unaffected group (6.7%, 11.9%). Lower average household income, lower education level, having a higher self-evaluated level of knowledge, being more worried about being infected, having no psychological support, greater property damage, and lower self-perceived health condition were significant associated with higher scores on the SAS and SDS. People living in Chongqing had higher SAS and SDS scores than those living in Yunnan Province. Conclusions:The prevalence of anxiety and depression of the affected group are higher than in the unaffected group during the COVID-19 outbreak in southwestern China in early Feb. 2020. The government should focus more on providing economic and medical support to improve the general population's mental state.

Increased intake of dietary carbohydrate that is fermented in the colon by the microbiota has been reported to decrease body weight, although the mechanism remains unclear. Here we use in vivo11C-acetate and PET-CT scanning to show that colonic acetate crosses the blood–brain barrier and is taken up by the brain. Intraperitoneal acetate results in appetite suppression and hypothalamic neuronal activation patterning. We also show that acetate administration is associated with activation of acetyl-CoA carboxylase and changes in the expression profiles of regulatory neuropeptides that favour appetite suppression. Furthermore, we demonstrate through 13C high-resolution magic-angle-spinning that 13C acetate from fermentation of 13C-labelled carbohydrate in the colon increases hypothalamic 13C acetate above baseline levels. Hypothalamic 13C acetate regionally increases the 13C labelling of the glutamate–glutamine and GABA neuroglial cycles, with hypothalamic 13C lactate reaching higher levels than the ‘remaining brain’. These observations suggest that acetate has a direct role in central appetite regulation.

Graphene with unique physical and chemical properties has shown various potential applications in biomedicine. In this work, a photosensitizer molecule, Chlorin e6 (Ce6), is loaded on polyethylene glycol (PEG)-functionalized graphene oxide (GO) via supramolecular π-π stacking. The obtained GO-PEG-Ce6 complex shows excellent water solubility and is able to generate cytotoxic singlet oxygen under light excitation for photodynamic therapy (PDT). Owing to the significantly enhanced intracellular trafficking of photosensitizers, our GO-PEG-Ce6 complex offers a remarkably improved cancer cell photodynamic destruction effect compared to free Ce6. More importantly, we show that the photothermal effect of graphene can be utilized to promote the delivery of Ce6 molecules by mild local heating when exposed to a near-infrared laser at a low power density, further enhancing the PDT efficacy against cancer cells. Our work highlights the promise of using graphene for potential multifunctional cancer therapies.

Graphene has emerged as interesting nanomaterials with promising applications in a range of fields including biomedicine. In this work, for the first time we study the long-term in vivo biodistribution of (125)I-labeled nanographene sheets (NGS) functionalized with polyethylene glycol (PEG) and systematically examine the potential toxicity of graphene over time. Our results show that PEGylated NGS mainly accumulate in the reticuloendothelial system (RES) including liver and spleen after intravenous administration and can be gradually cleared, likely by both renal and fecal excretion. PEGylated NGS do not cause appreciable toxicity at our tested dose (20 mg/kg) to the treated mice in a period of 3 months as evidenced by blood biochemistry, hematological analysis, and histological examinations. Our work greatly encourages further studies of graphene for biomedical applications.

Zn metal has been regarded as the most promising anode for aqueous batteries due to its high capacity, low cost, and environmental benignity. Zn anode still suffers, however, from low Coulombic efficiency due to the side reactions and dendrite growth in slightly acidic electrolyte. Here, the Zn plating/stripping mechanism is thoroughly investigated in 1 M ZnSO 4 electrolyte, demonstrating that the poor performance of Zn metal in mild electrolyte should be ascribed to the formation of a porous by-product (Zn 4 SO 4 (OH) 6 •xH 2 O) layer and serious dendrite growth. To suppress the side reactions and dendrite growth, a highly viscoelastic polyvinyl butyral (PVB) film, functioning as an artificial solid/electrolyte interphase (SEI), is homogeneously deposited on the Zn surface via a simple spin-coating This article is protected by copyright. All rights reserved.2 strategy. This dense artificial SEI film not only effectively blocks water from the Zn surface but also guides the uniform stripping/plating of Zn ions underneath the film due to its good adhesion, hydrophilicity, ionic conductivity, and mechanical strength. Consequently, this side-reaction-free and dendrite-free Zn electrode exhibits high cycling stability and enhanced Coulombic efficiency, which also contributes to enhancement of the full-cell performance when it is coupled with MnO 2 and LiFePO 4 cathodes.

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