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The development of near-infrared (NIR)-absorbing nanoagents for personalized multifunctional phototheranostics has attracted considerable attention in the past decade. Recently, the organic nanomaterials with good biosafety are considered as promising phototheranostic agents, while their facile synthesis remains challenging. Inspired by the preparation of carbon nanodots, we fabricate the NIR-absorbing phthalocyanine-based nanodots (ZnPc-NDs) using a facile method for multifunctional phototheranostics. The significant aggregation of phthalocyanines in nanodots induces a complete fluorescence quenching, which affords a high photothermal conversion efficiency (η = 45.7%). The ZnPc-NDs disperse very well in water media with an average diameter around 80 nm. Further conjugation of biotin on the surface of ZnPc-NDs affords tumor-targeting phthalocyanine nanodots (ZnPc-BT). The ZnPc-BT are demonstrated with favorable biocompatibility, intense photoacoustic signals, high tumor accumulation, and effective tumor suppression in vivo. This Article provides a new insight for further developing nanomedicines with imaging and therapeutic functions to treat cancers precisely and effectively.

Carbon dots (CDs) as an emerging type of carbon nanomaterials exhibit great potential in bioimaging applications owing to their superior optical properties and excellent biocompatibility. However, ...

Photothermal agents can transfer the absorbed light to heat energy, offering a noninvasive and controllable method to kill tumor cells and tissues. Here, we develop a simple and high-output strategy to prepare photothermal nanodots (MnPc-NDs) by the self-assembly and carbonization of manganese phthalocyanine. The aggregation of phthalocyanine molecules in the nanodots induces an efficient photothermal conversion. Thanks to the high thermal stability of phthalocyanine, the macrocycle is well preserved in the core of nanodots under the controlled hydrothermal temperature. Moreover, the as-prepared MnPc-NDs disperse well in aqueous solution with an average nanoscale size around 60 nm. The intense absorption in near-infrared (NIR) region, along with efficient reactive oxygen generation, high photothermal conversion efficiency (η = 59.8%), and excellent magnetic resonance contrast performances of MnPc-NDs endow them with great potential for MRI-guided cancer phototherapy. Therefore, the contribution provides a facile way to develop theranostic MnPc-NDs for precise and efficient cancer imaging and therapy.

Phototherapy has gained great attention in the past decade owing to the advantages of high selectivity and low toxicity. However, it’s still a challenge to develop a single photosensitizer that can achieve both photothermal and photodynamic effects. Herein, we design and synthesize a new organic compound (PIT) with a typical D-A-D structure through the covalent conjugation of perylene diimides (PDI) and triphenylamine (TPA). The amphiphilic PIT could be transformed to the nanoparticles (PIT NPs) through nanoprecipitation method. PIT NPs exhibit good water dispersibility with particle size around 70 nm. Because of the efficient NIR absorption, PIT NPs display high photothermal conversion efficiency (PCE) (η = 46.1 %) and strong photoacoustic signal under irradiation of 635 nm laser. Moreover, under the same laser irradiation, significant reactive oxygen species can be induced by PIT NPs both in aqueous solution and cancer cells. The MTT assay demonstrate the good biocompatibility and outstanding photocytotoxicity of PIT NPs. Thus, the as-prepared PIT NPs could be used as excellent candidates for photoacoustic imaging and photodynamic/photothermal therapy.

Near-infrared (NIR) light-activated phototherapy, such as photothermal therapy (PTT) and photodynamic therapy (PDT), has gained considerable attention due to the advantages of high efficiency and minimally invasiveness. However, the development of a single component therapeutic agent with clear structure and molecular weight that achieve photodynamic/photothermal synergistic therapy is still challenging. Herein, we design and synthesize a new smart photosensitizer (PRX) by conjugation of perylene diimide (PDI) and methylene violet (RAX). The typical donor-acceptor (D-A) structure of RAX facilitates the red-shift of absorption to the near-infrared (NIR) region. The amphiphilic PRX could self-assemble into monodispersed nanoparticles (PRX NPs) with enhanced and broadened absorption. Under a single 808 nm laser irradiation, PRX NPs could generate efficient reactive oxygen species (ROS) and heat simultaneously with the photothermal conversion efficiency as high as 59%. PRX NPs displays strong interaction with DNA and can damage plasmid DNA upon light irradiation. The biocompatibility and high phototoxicity of PRX NPs against A549 cells are further confirmed through MTT assay. Therefore, the as-prepared PRX NPs could be served as a promising antitumor nanoagent through photothermal/photodynamic combination manner.

Near-infrared (NIR)-absorbing organic nanoparticles (ONPs) are emerging candidates for "one-for-all" theranostic nanomaterials with considerations of safety and formulation in mind. However, facile fabrication methods and improvements in the photothermal conversion efficiency (PCE) and photostability are likely needed before a clinically viable set of candidates emerges. Herein, a new organic compound, [porphyrin-diketopyrrolopyrrole (Por-DPP)] with the donor-acceptor structure was synthesized, where porphyrin was used as a donor unit while diketopyrrolopyrrole was used as an acceptor unit. Por-DPP exhibited efficient absorption extending from visible to NIR regions. After self-assembling into nanoparticles (NPs) (∼120 nm), the absorption spectrum of Por-DPP NPs broadened and red-shifted to some extent, relative to that of organic molecules. Furthermore, the architecture of NPs enhanced the acceptor-donor structure, leading to emission quenching and facilitating nonradiative thermal generation. The PCE of Por-DPP NPs was measured and calculated to be 62.5%, higher than most of ONPs. Under 808 nm laser irradiation, the Por-DPP NPs possessed a distinct photothermal therapy (PTT) effect in vitro and can damage cancer cells efficiently in vivo without significant side effects after phototherapy. Thus, the small-molecule porphyrin-based ONPs with high PCE demonstrated promising application in photoacoustic imaging-guided PTT.

Manganese-doped carbon quantum dots (MnCQDs) were prepared through one-step hydrothermal method using citric acid and manganese tetraphenyl porphyrin as carbon sources in aqueous media. The structure of MnCQDs was confirmed by TEM, XRD, and XPS. The MnCQDs display a typical excitation-dependent emission behavior and exhibit bright green luminescence (with a peak at 482 nm) under UV irradiation (365 nm) and a fluorescence quantum yield of 13%. The MnCQDs can be used as a fluorescent probe for ferric ion in aqueous solution with a 220 nM detection limit. The MTT assay demonstrated the low cytotoxicity of MnCQDs towards HeLa cells. Due to the excitation-dependent emission properties, MnCQDs can be used as a multi-color (blue, green, and red) bioimaging agent in cancer cells and in living zebrafish. The application of MnCQDs as selective biosensing probe for Fe3+ was also realized in cells and zebrafish mode. Because of the existence of paramagnetic ions, MnCQDs demonstrate an enhanced magnetic resonance (MR) signal. Thus, the MnCQDs can serve as a positive contrast agent for MR imaging.

Evolution patterns of HBV QS between genotype B and C during vertical transmission are not well understood. In this study, we enrolled 10 HBV infected mother-infant pairs (four pairs with genotype B, four pairs with genotype C, and two with co-infection) without anti-viral therapy. Serum HBV DNA of mothers and infants were sequenced, HBV QS complexity and diversity were analyzed, polymorphisms and mutation sites were recorded, and phylogenetic trees were performed. Our result showed that the QS complexities in P (amino acid), C/PreC (amino acid), and PreS1 (nucleotide) gene were significantly higher in mothers than in infants in pairs with genotype C (P 0.05). Unlike genotype C, QS complexity of P gene (nucleotide) was significantly higher in infants than in mothers (P 0.05). QS diversities of full-length and most genes in genotype B were comparable between mothers and their infants (P > 0.05), in pairs with genotype C, dS of P, X, RT genes, genetic distance of Pre S1 gene (amino acid) and dN of Pre S1 gene were significant higher in mothers than in infants (P < 0.05). Several HBV mutations correlated with immune escape, e antigen loss and drug resistance were observed in infants. The results indicated that differences of HBV QS evolution patterns between genotype B and C during vertical transmission might contribute to distinct prognosis.

The carbon quantum dots termined with amine groups (CQDs-NH2) were synthesized in one-pot hydrothermal method with citric acid as carbon source and branched polyethylenimine (BPEI) as passive agent, which was then covalently linked to 1, 4, 7, 10-tetraazacyclononane (DOTA) framework to yield CQDs-DOTA. The CQDs-DOTA provide excellent ligand scaffolds for the chelation of lanthanide ions, yielding the related complexes CQDs-DOTA-Ln (Ln = Eu, Tb, Yb and Gd). The successful preparation of CQDs-DOTA-Ln was validated by TEM, XRD, XPS, and FT-IR spectroscopy. The CQDs-DOTA-Ln (Ln = Eu, Tb and Yb) exhibited the characteristic emissions of related lanthanide ions, indicating the CQDs could sensitize the luminescence of lanthanide ions. Besides, the CQDs-DOTA-Gd could serve as an excellent T1-weighted MR imaging probe due to the chelation of paramagnetic Gd (III) ions and good hydrophilicity. The cytotoxicity of CQDs-DOTA-Ln was evaluated through MTT assay upon HeLa cells. The images from fluorescence microscopy further verified their applications in bioimaging in vitro. Due to the good biocompatibility, low toxicity, and high contrast efficiency, the CQDs-DOTA-Ln with Vis/NIR fluorescence and MR multi-modal imaging performance could be used as potential contrast agents for clinic applications.

Supporting Information. (DOCX 151Â kb)

Culicoides biting midges (Diptera:Ceratopogonidae) cause a significant biting nuisance to humans, livestock, which are the biological vectors of a range of risky pathogens. Accurate illustration of vector play a key role in arthropod borne diseases surveillance. However, few studies have focused on the Culicoides, which caused bluetongue disease in 29 provinces of China since 1979. In this study, we assessed cytochrome oxidase subunit I (COI) mtDNA molecular marker for identification of ten major vector species and analyzed the Culicoides species community and diversity in different habitats. A total of 20,795 Culicoides samples collected from 11 sample sites were identified as 23 species belonging to 7 subgenera. Sequences of COI gene worked well as barcodes for identifying all the determined specimen in this study and were comparable with the existing sequence data from GenBank. We first reported COI barcode sequences of C. morisitai, C. insignipennis and C. homotomus. Morphological identification of Culicoides spp. samples within southern China appears relatively robust and some unidentified species were required further study. Our study shows that the COI sequence data can be used as a tool to identify species of Culicoides in Jiangxi Province. In our sampled area, the most abundant species was C. arakawae (61.89%), followed by C. oxystoma (13.77%), C. punctatus (10.10%), C. nipponensis (8.82%), C. homotomus (3.19%) and C.morisitai (1.17%) in this study. C. punctatus was the dominant species of Park habitat (62.22%), C. arakawae was the predominant species of Chicken habitat (96.66%), Vegetable plot habitat (92.0%), and Peasant household habitat (83.21%), respectively. C. oxystoma was the abundant species of Residential area habitat (40.11%), Hospital habitat (56.65%), and Pig & Cow habitat (48.77%), respectively. Results also show that the potential Bluetongue virus vectors belong to the Obsoletus and Pulicaris groups, are also included and relatively abundant, notably: Culicoides punctatus. These findings expand the current knowledge of Culicoides population composition in the southern part of China.

Aim A phylogeographical study of the widespread but phylogenetically isolated East Asian endemic tree species Tetracentron sinense (Trochodendraceae) was performed to evaluate whether and how Pleistocene and pre-Pleistocene climate changes helped to influence current phylogeographical patterns, and to describe the current patterns of genetic diversity and their implications for conservation.

Evolution patterns of HBV QS between genotype B and C during vertical transmission are not well understood. In this study, we enrolled 10 HBV infected mother-infant pairs (four pairs with genotype B, four pairs with genotype C, and two with co-infection) without anti-viral therapy. Serum HBV DNA of mothers and infants were sequenced, HBV QS complexity and diversity were analyzed, polymorphisms and mutation sites were recorded, and phylogenetic trees were performed. Our result showed that the QS complexities in P (amino acid), C/PreC (amino acid), and PreS1 (nucleotide) gene were significantly higher in mothers than in infants in pairs with genotype C (P0.05), however, full-length and other genes showed non-significant differences (P0.05). Unlike genotype C, QS complexity of P gene (nucleotide) was significantly higher in infants than in mothers (P0.05) in pairs with genotype B, similarly, QS complexities of full-length and other genes (except Pre S2) were also higher in infants than in mothers but without significant differences (P0.05). QS diversities of full-length and most genes in genotype B were comparable between mothers and their infants (P0.05), in pairs with genotype C, dS of P, X, RT genes, genetic distance of Pre S1 gene (amino acid) and dN of Pre S1 gene were significant higher in mothers than in infants (P0.05). Several HBV mutations correlated with immune escape, e antigen loss and drug resistance were observed in infants. The results indicated that differences of HBV QS evolution patterns between genotype B and C during vertical transmission might contribute to distinct prognosis.