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•We established an association between microplastics exposure and the occurrence of a disease.•Our findings highlight the health risks of a subset of the population with high exposure ...to microplastics.•Our study is the first to find an increased risk of insulin resistance contributed by gut-liver axis.
Human uptake abundance of microplastics via various pathways, and they accumulate in human liver, kidney, gut and even placenta (especially with a diameter of 1 μm or less). Recent scientific studies have found that exposure to microplastics causes intestinal inflammation and liver metabolic disorder, but it remains largely unknown that whether the damage and inflammation may cause further development of severe diseases. In this study, we discovered one of such potential diseases that may be induced by the exposure to small-sized microplastics (with a diameter of 1 μm) performing a multi-organ and multi-omics study comprising metabolomics and microbiome approaches. Unlike other animal experiments, the dosing strategy was applied in mice according to the daily exposure of the highly exposed population, which was more environmentally relevant and reflective of real-world human exposure. Our studies on the gut-liver axis metabolism have shown that the crosstalk between the gut and liver ultimately leaded to insulin resistance and even diabetes. We proactively verified this hypothesis by measuring the levels of fasting blood glucose and fasting insulin, which were found significantly elevated in the mice with microplastics exposure. These results indicate the urgent need of large-scale cohort evaluation on epidemiology and prognosis of insulin resistance after microplastics exposure in future.
Recently, plasmonic copper sulfide (Cu2–x S) nanocrystals (NCs) have attracted much attention as materials for photothermal therapy (PTT). Previous reports have correlated photoinduced cell death to ...the photothermal heat mechanism of these NCs, and no evidence of their photodynamic properties has been reported yet. Herein we have prepared physiologically stable near-infrared (NIR) plasmonic copper sulfide NCs and analyzed their photothermal and photodynamic properties, including therapeutic potential in cultured melanoma cells and a murine melanoma model. Interestingly, we observe that, besides a high PTT efficacy, these copper sulfide NCs additionally possess intrinsic NIR induced photodynamic activity, whereupon they generate high levels of reactive oxygen species. Furthermore, in vitro and in vivo acute toxic responses of copper sulfide NCs were also elicited. This study highlights a mechanism of NIR light induced cancer therapy, which could pave the way toward more effective nanotherapeutics.
Mesoporous carbon nanospheres containing porphyrin‐like metal centers (denoted as “PMCS”) are successfully synthesized by the pyrolysis of an imidazolate framework using a mesoporous‐silica ...protection strategy. The PMCS allow infrared and photoacoustic imaging and synergetic photothermal therapy/photodynamic therapy derived from the porphyrin‐like moieties, offering the possibility of real‐time monitoring of therapeutic processes and image‐guided precise conformal phototherapy. PMCS thus represent a novel multifunctional theranostic platform for improved treatment efficiencies.
Although near‐infrared (NIR)‐light‐mediated photothermal thrombolysis has been investigated to overcome the bleeding risk of clinical clot‐busting agents, the secondary embolism of post‐phototherapy ...fragments (>10 µm) for small vessels should not be ignored in this process. In this study, dual‐modality photothermal/photodynamic thrombolysis is explored using targeting nanoagents with an emphasis on improving biosafety as well as ameliorating the thrombolytic effect. The nanoagents can actively target glycoprotein IIb/IIIa receptors on thrombus to initiate site‐specific thrombolysis by hyperthermia and reactive oxygen species under NIR laser irradiation. In comparison to single photothermal thrombolysis, an 87.9% higher re‐establishment rate of dual‐modality photothermal/photodynamic thrombolysis by one‐time treatment is achieved in a lower limb thrombosis model. The dual‐modality thrombolysis can also avoid re‐embolization after breaking fibrin into tiny fragments. All the results show that this strategy is a safe and validated protocol for thrombolysis, which fits the clinical translational trend of nanomedicine.
Dual‐modality photothermal/photodynamic synergistic thrombolysis, based on nanoparticles composed of glycoprotein IIb/IIIa receptors targeting agents and metal–organic‐framework‐derived carbon nanostructures, is applied for increasing therapeutic efficacy by inorganic‐photosensitizer‐initiated reactive oxygen species and hyperthermia, preventing high bleeding risk of the systematic fibrinolytic therapy.
Novel upconversion NaYF4:Yb3+,Er3+/TiO2 core–shell nanoparticles (NPs) are synthesized and used to prepare the photoelectrode (PE) of dye-sensitized solar cells (DSSCs). The morphology, structure, ...photoluminescence characterization of the NaYF4:Yb3+,Er3+/TiO2 core–shell NPs and the photoelectric performance, alternating current impedance spectroscopy of DSSCs are characterized using transmission electron microscopy, X-ray diffraction, upconversion luminescence (UCL) spectrofluorimetry and electrochemistry. Compared with the pure TiO2 PE or the NaYF4:Yb3+,Er3+ upconversion NPs and TiO2 simply mixed prepared PE as the volume ratio of the core–shell structure, the DSSCs with the upconversion core–shell PE show a greater photovoltaic efficiency. The energy conversion efficiency of the DSSCs with a NaYF4:Yb3+,Er3+/TiO2 PE is 23.1% higher than with a pure TiO2 PE and 99.1% higher than with a mixed PE using the same conditions. This enhancement is due to the UCL core extending the spectral response range of DSSCs to the infrared region and their particular shell structure, retaining its semiconductor character. This method represents a novel approach to increase the efficiencies of DSSCs.
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► NaYF4:Yb3+,Er3+/TiO2 core–shell nanoparticles as the photoelectrode of DSSCs. ► It can convert infrared to visible luminescence and retain semiconductor character. ► The DSSCs with this core–shell appeared the best photoelectric performances.
Environmental exposure and health risk upon engineered nanomaterials are increasingly concerned. The family of mesoporous carbon nanomaterials（MCNs） is a rising star in nanotechnology for ...multidisciplinary research with versatile applications in electronics,energy and gas storage, and biomedicine. Meanwhile, there is mounting concern on their environmental health risks due to the growing production and usage of MCNs. The lung is the primary site for particle invasion under environmental exposure to nanomaterials. Here, we studied the comprehensive toxicological profile of MCNs in the lung under the scenario of moderate environmental exposure. It was found that at a low concentration of 10 μg/mL MCNs induced biophysical inhibition of natural pulmonary surfactant. Moreover, MCNs at similar concentrations reduced viability of J774 A.1 macrophages and lung epithelial A549 cells.Incubating with nature pulmonary surfactant effectively reduced the cytotoxicity of MCNs.Regarding the pro-inflammatory responses, MCNs activated macrophages in vitro, and stimulated lung inflammation in mice after inhalation exposure, associated with lung fibrosis.Moreover, we found that the size of MCNs played a significant role in regulating cytotoxicity and pro-inflammatory potential of this nanomaterial. In general, larger MCNs induced more pronounced cytotoxic and pro-inflammatory effects than their smaller counterparts. Our results provided valuable information on the toxicological profile and environmental health risks of MCNs, and suggested that fine-tuning the size of MCNs could be a practical precautionary design strategy to increase safety and biocompatibility of this nanomaterial.
•Unsteady LN2 cavitation over a twisted 3D hydrofoil is modeled based on LES.•Model with thermal effects is validated by comparing experiments.•Different cavity morphology evolution with water is ...illustrated.•Different dynamic shedding mechanisms with water are illuminated.
The cavitating flow of liquid nitrogen (LN2) over a three-dimensional (3D) twisted hydrofoil is simulated based on homogeneous mixture model with LES turbulent closure. The numerical model is validated by modeling the cavitating flow of LN2 over a hydrofoil in Hord’s experiments. The general results, such as the horseshoe U-shape cavity morphology evolutions, are presented and compared with the cases of water cavitation. The emphasis is focused on illustrating the differences of complex shedding mechanisms in thermal cavitation with thermal effects and isothermal cavitation without thermal effects in the complex 3D flow. The shedding frequency of thermal LN2 cavitation is found to be smaller than the isothermal case without thermal effects. The sheet cavity surface is not continuous in thermal cavitation and the maximum cavity volume is also smaller than that of isothermal case. Different from the isothermal cavitating flow in which the strong re-entrant jet initiated in the tail of the cavity rolling up the entire sheet cavity is the main reason causing the cavity shedding, the interactions of cavity and small vortices have great responsibility for the formations of cavity cloud in the thermal cases. The results offer deep insight into the physics of cryogenic cavitation dynamics.
•Unsteady LH2 cavitation over an 3D hydrofoil is modeled based on LES.•Frequency characteristics of LH2 cavitation cloud are specially analyzed.•Strouhal number is much lower than water at σ/2α > 2, ...while same at σ/2α < 2.•Explanations are given based on interactions of vortex flow and thermal effects.
Large eddy simulation on unsteady cavitating flow of liquid hydrogen over a three-dimensional NACA0015 hydrofoil with the attack angle (α) of 6° are carried out to investigate the dynamic features of cavity with the existence of thermal effects. The numerical model considers the compressibility of both liquid and vapor phase, and is validated by comparing the results with the available experimental data. Special emphasis is put on analyzing the frequency characteristics of cavitation cloud. Strouhal number (St) is plotted against σ/2α (σ is cavitation number), and the water cavitation data reported by Andrt et al. are also used as a reference. It is found that the St number for LH2 cavitation is much smaller than the water, in which the thermal effects are generally not considered, at the same σ/2α value when it is greater than about 2.0, while it returns to the same level as water when σ/2α decreases to below 2.0. The reason is primarily ascribed to the thermal effects, and the detailed explanations are given based on the recognitions that the shedding mechanism of cavitation clouds is predominated by the combined action of the vortex flow and thermal effects. While, when σ/2α decreases to a critical value, the relative effect of the thermal effects on the cavitation dynamics is greatly weakened compared with the mechanism due to the vortex flow, like those in isothermal cavitation flow in traditional fluids. The results provide a deeper understanding of the cryogenic fluid cavitation flow.
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•Graphene oxide alters the types of hepatic macrophages at different time points.•Graphene oxide has distinctly different effects on the population of platelets in the liver and ...spleen.•Graphene oxide triggers accelerated haematopoiesis in the spleen but not in the bone marrow or lung.
In this study, we comprehensively explored graphene oxide (GO)-induced systemic immune responses and interference with hematopoiesis in mice upon GO intravenous injection. In the liver and spleen, GO led to alterations in immune components at different time points. GO exposure showed an effect on the populations of different types of hepatic macrophages. In the liver, the populations of macrophages mainly affected by GO including Kupffer cells and monocyte-derived macrophages. Stimulated hepatic inflammation led to the infiltration of platelets from the circulation into the liver and decreased peripheral platelets population at day 1. Interestingly, a decreased platelet population was observed on day 7 in the spleen. GO also led to accelerated hematopoiesis in the spleen. Therefore, the possible forced generation of more platelets and the release of mature platelets from the spleen contributed to the increased circulating platelet count on day 7. Therefore, although GO showed a low potential to induce severe inflammation in the liver and spleen, it disrupted hematopoiesis in the spleen, which contributed to fluctuations in circulating platelet counts. The interaction of GO with the immune system warrants comprehensive study for gaining better understanding.
Nanozymes have attracted extensive interest owing to their high stability, low cost and easy preparation, especially in the field of cancer therapy. However, the relatively low catalytic activity of ...nanozymes in the tumor microenvironment (TME) has limited their applications. Herein, we report a novel nanozyme (PtFe@Fe3O4) with dual enzyme‐like activities for highly efficient tumor catalytic therapy. PtFe@Fe3O4 shows the intrinsic photothermal effect as well as photo‐enhanced peroxidase‐like and catalase‐like activities in the acidic TME, thereby effectively killing tumor cells and overcoming the tumor hypoxia. Importantly, a possible photo‐enhanced synergistic catalytic mechanism of PtFe@Fe3O4 was first disclosed. We believe that this work will advance the development of nanozymes in tumor catalytic therapy.
Double attack: A novel nanozyme (PtFe@Fe3O4) with dual enzyme‐like activities was developed for deep pancreatic cancer catalytic therapy. The PtFe@Fe3O4 nanozyme shows photo‐enhanced peroxidase‐like and catalase‐like activities under the acidic tumor microenvironment, as well as intrinsic photothermal effect, effectively killing tumor cells and overcoming the tumor hypoxia.
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