Although intestinal flora are crucial in maintaining immune homeostasis of the intestine, the role of intestinal flora in immune responses at other mucosal surfaces remains less clear. Here, we show that intestinal flora composition critically regulates the toll-like receptor 7 (TLR7) signaling pathway following respiratory influenza virus infection. TLR7 ligands rescued the immune impairment in antibiotic-treated mice. Intact microbiota provided signals leading to the expression of mRNA for TLR7, MyD88, IRAK4, TRAF6, and NF-κB at steady state. Significant changes in the composition of culturable commensal bacteria reduced the expression levels of components of the TLR7 signaling pathway. Our results reveal the importance of intestinal flora in regulating immunity in the respiratory mucosa through the upregulation of the TLR7 signaling pathway for the proper activation of inflammasomes.

A reliable surface-enhanced Raman scattering (SERS) substrate composed of two-dimensional (2D) MXene (Ti 3 C 2 T x ) nanosheets and gold nanorods (AuNRs) is designed and fabricated for sensitive detection of organic pollutants. The AuNRs are uniformly distributed on the surface of the 2D MXene nanosheets because of the strong electrostatic interactions, forming abundant SERS hot spots. The MXene/ AuNR SERS substrate exhibits high sensitivity and excellent reproducibility in the determination of common organic dyes such as rhodamine 6G, crystal violet, and malachite green. The detection limits are 1 × 10 −12 , 1 × 10 −12 , and 1 × 10 −10 M, and relative standard deviations determined from 13 areas on each sample are 18.1, 10.1, and 15.6%, respectively. In the determination of more complex organic pesticides and pollutants, the substrate also shows excellent sensitivity and quantitative detection, and the detection limits for thiram and diquat of 1 × 10 −10 and 1 × 10 −8 M, respectively, are much lower than the contaminant levels stipulated by the US Environmental Protection Agency. The MXene/AuNR composite constitutes an efficient SERS platform for reliable and high-sensitivity environmental analysis and food safety monitoring.

Hepatic injury is often accompanied by pulmonary inflammation and tissue damage, but the underlying mechanism is not fully elucidated. Here we identify hepatic miR-122 as a mediator of pulmonary inflammation induced by various liver injuries. Analyses of acute and chronic liver injury mouse models confirm that liver dysfunction can cause pulmonary inflammation and tissue damage. Injured livers release large amounts of miR-122 in an exosome-independent manner into the circulation compared with normal livers. Circulating miR-122 is then preferentially transported to mouse lungs and taken up by alveolar macrophages, in which it binds Toll-like receptor 7 (TLR7) and activates inflammatory responses. Depleting miR-122 in mouse liver or plasma largely abolishes liver injury-induced pulmonary inflammation and tissue damage. Furthermore, alveolar macrophage activation by miR-122 is blocked by mutating the TLR7-binding GU-rich sequence on miR-122 or knocking out macrophage TLR7. Our findings reveal a causative role of hepatic miR-122 in liver injury-induced pulmonary dysfunction.

As new 2D layered nanomaterials, Bi2O2Se nanoplates have unique semiconducting properties that can benefit biomedical applications. Herein, a facile top‐down approach for the synthesis of Bi2O2Se quantum dots (QDs) in a solution is described. The Bi2O2Se QDs with a size of 3.8 nm and thickness of 1.9 nm exhibit a high photothermal conversion coefficient of 35.7% and good photothermal stability. In vitro and in vivo assessments demonstrate that the Bi2O2Se QDs possess excellent photoacoustic (PA) performance and photothermal therapy (PTT) efficiency. After systemic administration, the Bi2O2Se QDs accumulate passively in tumors enabling efficient PA imaging of the entire tumors to facilitate imaging‐guided PTT without obvious toxicity. Furthermore, the Bi2O2Se QDs which exhibit degradability in aqueous media not only have sufficient stability during in vivo circulation to perform the designed therapeutic functions, but also can be discharged harmlessly from the body afterward. The results reveal the great potential of Bi2O2Se QDs as a biodegradable multifunctional agent in medical applications.

AIM:To evaluate the clinical effect of high-intensity focused ultrasound (HIFU) in the treatment of patients with liver cancer.METHODS: HIFU treatment was performed in 100 patients with liver cancer under general anesthesia and by a targeted ultrasound. Evaluation of efficacy was made on the basis of clinical symptoms, liver function tests, AFP, MRI or CT before and after the treatment. RESULTS:After HIFU treatment, clinical symptoms were relieved in 86.6%(71/82) of patients. The ascites disappeared in 6 patients. ALT (95±44) U/L and AST (114±58) U/L before HIFU treatment were reduced to normal in 83.3%(30/36) and 72.9%(35/48) patients, respectively, after the treatment. AFP was lowered by more than 50% in 65.3%(32/49) patients. After HIFU treatment, MRI or CT findings indicated coagulation necrosis and blood supply reduction or disappearance of tumor in the target region.CONCLUSION: HIFU can efficiently treat the patients with liver cancer. It will offer a significant noninvasive therapy for local treatment of liver tumor.

Silver nanoparticles (AgNPs) are increasingly used in daily life for their antibacterial properties, but their low stability and high cytotoxicity hamper practical applications. In this work, sodium 1-naphthalenesulfonate-functionalized reduced graphene oxide (NA-rGO) was used as a substrate for AgNPs to produce a AgNP-NA-rGO hybrid. This hybrid showed substantially higher antibacterial activity than polyvinyl pyrrolidone (PVP)-stabilized AgNPs, and the AgNPs on NA-rGO were more stable than the AgNPs on PVP, resulting in long-term antibacterial effects. More importantly, this hybrid showed excellent water solubility and low cytotoxicity, suggesting the great potential application as sprayable reduced graphene oxide based antibacterial solutions.

Carbonaceous nanospheres with silver nanoparticles (CNs-Ag) composites were prepared by a facile and low cost method. Silver nanoparticles were successfully loaded onto the surface of carbonaceous nanospheres, which were examined by X-ray diffraction, UV-vis spectra, transmission electron microscopy, energy dispersive spectrometry and X-ray photoelectron spectroscopy. The antibacterial properties of the CNs-Ag composites were investigated by the kinetics of bacterial growth and a diskdiffusion test. The cytotoxicity of the CNs-Ag composites was determined by MTT assay. The results suggest that the obtained CNs-Ag composites exhibit enhanced antibacterial properties and lower cytotoxicity in comparison with silver nanoparticles. The composites may be alternative antibacterial materials with mild cytotoxicity in biomedical fields.

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