Inflammatory macrophages play pivotal roles in the development of atherosclerosis. Theranostics, a promising approach for local imaging and photothermal therapy of inflammatory macrophages, has drawn increasing attention in biomedical research. In this study, gold nanorods (Au NRs) were synthesized, and their in vitro photothermal effects on the macrophage cell line (Ana-1 cells) under 808 nm near infrared reflection (NIR) were investigated by the CCK8 assay, calcein AM/PI staining, flow cytometry, transmission electron microscopy (TEM), silver staining and in vitro micro-computed tomography (CT) imaging. These Au NRs were then applied to an apolipoprotein E knockout (Apo E) mouse model to evaluate their effects on in vivo CT imaging and their effectiveness as for the subsequent photothermal therapy of macrophages in femoral artery restenosis under 808 nm laser irradiation. In vitro photothermal ablation treatment using Au NRs exhibited a significant cell-killing efficacy of macrophages, even at relatively low concentrations of Au NRs and low NIR powers. In addition, the in vivo results demonstrated that the Au NRs are effective for in vivo imaging and photothermal therapy of inflammatory macrophages in femoral artery restenosis. This study shows that Au nanorods are a promising theranostic platform for the diagnosis and photothermal therapy of inflammation-associated diseases.
Background: Reconstruction of the aortic major branches during thoracic endovascular aortic repair is complicated because of the complex anatomic configuration and variation of the aortic arch. In situ laser fenestration has shown great potential for the revascularization of aortic branches. This study aims to evaluate the feasibility, effectiveness, and safety of in situ laser fenestration on the three branches of the aortic arch during thoracic endovascular aortic repair. Methods and Results: Before clinical application, the polytetrafluoroethylene and Dacron grafts were fenestrated by an 810‐nm laser system ex vivo, which did not damage the bare metal portion of the endografts and created a clean fenestration while maintaining the integrity of the endografts. In vivo , 6 anesthetized female swine survived after this operation, including stent‐graft implantation in the aortic arches, laser fenestration, and conduit implantation through the innominate arteries and the left carotid arteries. Based on the animal experiments, in situ laser fenestration during thoracic endovascular aortic repair was successively performed on 24 patients (aged 33–86 years) with aortic artery diseases (dissection type A: n=4, type B: n=7, aneurysm: n=2, mural thrombus: n=7). Fenestration of 3 aortic branches was performed in 2 (8.3%) patients. Both the left carotid artery and the left subclavian artery were fenestrated in 6 (25%) patients. Only left subclavian artery fenestration surgery was done in 16 (66.7%) patients. Among these patients, 1 fenestration was abandoned secondary to an acute takeoff of the innominate artery in a type III aortic arch. The average operative time was 137±15 minutes. The technical success rate was 95.8% (n=23). No fenestration‐related complications or neurological morbidity occurred after this operation. During a mean postoperative 10‐month follow‐up (range: 2–17 months), 1 patient died of severe pneumonia, and all the left subclavian artery and carotid artery stents were patent with no fenestration‐related endoleaks upon computed tomography angiography images. Conclusions: In situ laser fenestration is a feasible, effective, rapid, repeatable, and safe option for the reconstruction of aortic arch during thoracic endovascular aortic repair, which might be available to revascularize the 3 branches. However, follow‐up periods should be extended to evaluate the robustness of this technique.
Background: Preclinical studies have suggested that adipose-derived mesenchymal stem cells (ADSCs) transplantation can suppress abdominal aortic inflammation and aneurysm expansion through paracrine factors. Yet, the mechanism of action is not fully understood. In the present study, we further examined the function and mechanism of ADSC-derived exosomes (ADSC-exos) and their microRNA-17-5p (miR-17-5p) on the abdominal aortic aneurysm (AAA) progression. Methods: ADSC-exos were isolated and identified. DiR and PKH67 staining were used to trace ADSC-exo in vivo and in vitro. Raw264.7 cells were applied to perform in vitro experiments, while a murine AAA model induced using angiotensin II (Ang II) was used for in vivo testing. The expression level of miR-17-5p in macrophages and Ang II-treated macrophages after ADSC-exos treatment was determined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The target relation between miR-17-5p and thioredoxin-interacting protein (TXNIP) was identified by a dual-luciferase reporter gene assay. Artificial activation and block of experiments of miR-17-5p and TXNIP were conducted to clarify their functions in inflammation during AAA progression. The severity of AAA between groups was assessed by maximal aorta diameter, AAA incidence, survival rate, and histological stainings. Besides, inflammasome-related proteins and macrophage pyroptosis were further evaluated using western blot, RT-qPCR, and enzyme-linked immunosorbent assay (ELISA). Results: The ADSC-exos were isolated and identified. In vivo testing showed that ADSC-exos were mainly distributed in the liver. Meanwhile, in vitro experiments suggested that ADSC-derived exosomes were taken up by macrophages, while inside, ADSC-exos miR-17-5p decreased a TXNIP induced by Ang II by directly binding to its 3′-untranslated region (3’UTR). Furthermore, overexpression of miR-17-5p enhanced the therapeutic function of ADSC-exos on inflammation during AAA expansion in vivo, while its inhibition reversed this process. Finally, overexpressed TXNIP triggered macrophage pyroptosis and was alleviated by ADSC-derived exosomes in vitro. Conclusion: ADSC-exos miR-17-5p regulated AAA progression and inflammation via the TXNIP-NLRP3 signaling pathway, thus providing a novel insight in AAA treatment.
8 November 2019 in Journal of Materials Chemistry A
With the increasing demand for wearable and implantable electronics, structured sensors with exceptional performance in sensitivity, stretchability, biocompatibility, and adhesion to the biological surfaces have become essential. Here, we report a novel graphene strain sensor, whose structure contains a carefully selected graphene foam (GF) and polyacrylamide/calcium-alginate (PAM/CA) double network hydrogel coupled with chitosan, can meet the above requirements to the maximum extent. Taking the advantage of the excellent electrical properties of graphene and the mechanical properties of hydrogel, this strain sensor can measure an exceptionally wide range of strain up to 500%, which allows us to monitor and distinguish almost all human body motions, with a gauge factor of ∼1800, which is up to 3 orders of magnitude larger than the 0.1–1000 value reported previously. The device also shows high stability and excellent durability for 1000 cycles. Most importantly, the chitosan-bridge and skin-like elastic modulus of 8–90 kPa allow conformal adhesion between the skin and hydrogel, with the adhesion energy of ∼200 J m−2. Moreover, this structured sensor is highly biocompatible and can be implanted in vivo, and has further potential in clinical applications.