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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.

but still limited to noble metal, such as iridium (Ir) and ruthenium (Ru). [3] The high cost of noble metal and scarcity in resources have hindered their wide application as the catalytic electrode for H 2 production. Therefore it is urgent to obtain high performance OER catalysts based on the earth-abundant elements other than the noble metal-based catalysts (IrO 2 and RuO 2 ). [4] The layered double hydroxides (LDHs), [5] also known as hydrotalcite-like clays, is a typical non-noble-metal-based material that composed of layers of divalent and trivalent metal cations coordinated to hydroxide anions with guest anions (typically CO 3 2− ) intercalated between the layers. [6] The highly tunable structures, such as layer numbers, metal species, interlayer spacing, and more importantly, the specific cation arrangements in the hydroxide layers, make LDHs-based materials as promising OER catalysts to replace the state-of-the-art noble metal based catalysts. [7] The NiFe LDHs is nowadays known as one of the most active OER catalysts with a low overpotential and high electrolysis current. [8] However, it is still suffering from poor electronic conductivity that hindering its further improvement and practical application. [9] Recently, tremendous efforts have been devoted to enhance the electrocatalytic activity, such as, exfoliation to fabricate a single layer structure, [10] integrating the LDHs nanosheets to form array on a conductive substrate, [11] loading noble metal on the surface, [12] modification the interlayer anion to change the electronic structure, [13] sulfurization, [14] defect engineering to increase the active site, [15] topotactic reduction to metallic nanosheets, [16] and doping. [17] It is already known that Fe in NiFe LDHs is the key aspect for the high OER catalytic performance, [18] so we can modify the chemical environment of Fe by incorporating other valence variable transition metals (such as Co [17a] and Mn [17b] ) into NiFe LDHs laminate to enhance the catalyst activity. Vanadium is an earth-abundant element and its activity for electrochemical water oxidation has been explored as active sites in NiV LDHs. [19] However, as a typical transition metal with a series of valence states, the electron interaction and synergetic effect between V and other metals in the laminate of LDHs have never been touched. On the other hand, the integrating of nanosheets materials can enhance the intrinsic activity of OER by providing electron transfer pathways from electron-conductive Binary NiFe layer double hydroxide (LDH) serves as a benchmark non-noble metal electrocatalyst for the oxygen evolution reaction, however, it still needs a relatively high overpotential to achieve the threshold current density. Herein the catalyst's electronic structure is tuned by doping vanadium ions into the NiFe LDHs laminate forming ternary NiFeV LDHs to reduce the onset potential, achieving unprecedentedly efficient electrocatalysis for water oxidation. Only 1.42 V (vs reversible hydrogen electrode (RHE), ≈195 mV overpoten...

No abstract

Reduced graphene oxide (RGO) is an intriguing nanomaterial with tremendous potential for many applications. Although considerable efforts have been devoted to develop the reduction methods, it still needs further improvement, and how to choose an appropriate one for a specific application is a troublesome problem. In this study, RGOs were prepared by six typical reduction methods: N 2 H 4 3 H 2 O, NaOH, NaBH 4 , solvothermal, high-temperature, and two-step. The samples were systematic compared by four aspects: dispersibility, reduction degree, defect repair degree, and electrical conductivity. On the basis of the comparison, a simple evaluation criterion was proposed for qualitatively judging the quality of RGO. This evaluation criterion would be helpful to understand the mechanism of reduction and design more ideal reduction methods.

Recent studies have demonstrated that long non-coding RNAs (lncRNAs) are regarded as useful tools for cancer detection, particularly for the early stage; however, little is known about their diagnostic impact on gastric cancer (GC). We hypothesized that GC-related lncRNAs might release into the circulation during tumor initiation and could be utilized to detect and monitor GC. 8 lncRNAs which previously found to be differently expressed in GC were selected as candidate targets for subsequent circulating lncRNA assay. After validating in 20 pairs of tissues and plasma in training set, H19 was selected for further analysis in another 70 patients and 70 controls. Plasma level of H19 was significantly higher in GC patients compared with normal controls (p < 0.0001). By receiver operating characteristic curve (ROC) analysis, the area under the ROC curve (AUC) was 0.838; p < 0.001; sensitivity, 82.9%; specificity, 72.9%). Furthermore, H19 expression enabled the differentiation of early stage GC from controls with AUC of 0.877; sensitivity, 85.5%; specificity, 80.1%. Besides, plasma levels of H19 were significantly lower in postoperative samples than preoperative samples (p = 0.001). In conclusion, plasma H19 could serve as a potential biomarker for diagnosis of GC, in particular for early tumor screening.

We developed a novel methodology for the general synthesis of non-precious transition metal–nitrogen–carbon electrocatalysts based on formamide condensation.

Parkinson's Disease (PD) is currently considered a systemic neurodegenerative disease manifested with not only motor but also non-motor symptoms. In particular, weight loss and malnutrition, a set of frequently neglected non-motor symptoms, are indeed negatively associated with the life quality of PD patients. Moreover, comorbidity of weight loss and malnutrition may impact disease progression, giving rise to dyskinesia, cognitive decline and orthostatic hypotension, and even resulting in disability and mortality. Nevertheless, the underlying mechanism of weight loss and malnutrition in PD remains obscure and possibly involving multitudinous, exogenous or endogenous, factors. What is more, there still does not exist any weight loss and malnutrition appraision standards and management strategies. Given this, here in this review, we elaborate the weight loss and malnutrition study status in PD and summarize potential determinants and mechanisms as well. In conclusion, we present current knowledge and future prospects of weight loss and malnutrition in the context of PD, aiming to appeal clinicians and researchers to pay a closer attention to this phenomena and enable better management and therapeutic strategies in future clinical practice.