Acute liver injury (ALI) has an elevated fatality rate due to untimely and ineffective treatment. Although, schisandrin B (SchB) has been extensively used to treat diverse liver diseases, its therapeutic efficacy on ALI was limited due to its high hydrophobicity. Palmitic acid-modified serum albumin (PSA) is not only an effective carrier for hydrophobic drugs, but also has a superb targeting effect via scavenger receptor-A (SR-A) on the M1 macrophages, which are potential therapeutic targets for ALI. Compared with the common macrophage-targeted delivery systems, PSA enables site-specific drug delivery to reduce off-target toxicity. Herein, we prepared SchB-PSA nanoparticles and further assessed their therapeutic effect on ALI. In vitro, compared with human serum albumin encapsulated SchB nanoparticles (SchB-HSA NPs), the SchB-PSA NPs exhibited more potent cytotoxicity on lipopolysaccharide (LPS) stimulated Raw264.7 (LAR) cells, and LAR cells took up PSA NPs 8.79 times more than HSA NPs. As expected, the PSA NPs also accumulated more in the liver. Moreover, SchB-PSA NPs dramatically reduced the activation of NF-κB signaling, and significantly relieved inflammatory response and hepatic necrosis. Notably, the high dose of SchB-PSA NPs improved the survival rate in 72 h of ALI mice to 75%. Hence, SchB-PSA NPs are promising to treat ALI.
In this study, a novel long-lived room-temperature phosphorescent (RTP) carbon dots (P-CDs) with the properties of ultraviolet/visible (UV/Vis) light photoresponsive oxidase-like nanozyme were synthesized from diethylenetriaminepentaacetic acid and through a one-step hydrothermal method. The aim was to improve the photosensitive oxygen activation ability. Because of relatively high triplet excited state (T1) quantum yield and long T1-state exciton lifetime, the P-CDs can efficiently convert O2 to 1O2 through efficient T1 energy transfer and by prolonging the energy transfer time between T1 excitons and O2 molecules. The growth inhibition effect of P-CDs on Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) were studied using the strong oxidizing ability of 1O2. Then the P-CDs were made into P-CDs/PVA films, which effectively prolonged the preservation period of fruits under photodynamic antibacterial action. The good biocompatibility and efficient photosensitive oxygen activation can make P-CDs a more practically useful oxidase-like nanozyme.
With the advanced discoveries in the field of pathogenesis, a series of cerebral diseases, such as cerebral ischaemia, Alzheimer's disease, and depression, have been found to have multiple signalling targets in the microenvironment. Only a few existing agents have been shown to have curative effects due to this specific circumstance. In recent decades, active ingredients isolated from natural plants have been shown to be crucial for original drug development. Geniposide, mainly extracted from Gardenia jasminoides Ellis, is representative of these natural products. Geniposide demonstrates various biological activities in the treatment of cerebral, cardiovascular, hepatic, tumorous, and other diseases. The multiple protective effects of geniposide on the brain have especially drawn increasing attention. Thus, this article specifically reviews the characteristics of current models of cerebral ischaemia and illustrates the possible effects of geniposide and its pathogenetic mechanisms on these models. Geniposide has been shown to significantly reduce the area of cerebral infarction and alleviate neuronal damage and necrosis mainly by inhibiting inflammatory signals, including NLRP3, TNF-α, IL-6, and IL-1β. Neuronal protection was also involved in activating the PI3K/Akt and Wnt/catenin pathways. Geniposide was able to increase autophagy and inhibit apoptosis by regulating the function of mTOR in treating Alzheimer's disease. Geniposide has also been shown to act as a glucagon-like peptide-1 receptor (GLP-1R) agonist to reduce amyloid plaques and inhibit oxidative stress to alleviate memory impairment as well as synaptic loss. Moreover, geniposide has been shown to exert antidepressant effects primarily by regulating the hypothalamic-pituitary-adrenal (HPA) axis. Detailed explorations have shown that the biological activities of inhibiting inflammatory cytokine secretion, alleviating oxidative stress, and suppressing mitochondrial damage are also involved in the mechanism of action of geniposide. Therefore, geniposide is a promising agent awaiting further exploration for the treatment of cerebral diseases via various phenotypes or signalling pathways.
Developing novel photoresponsive oxidase mimics is highly useful for environmental pollution monitoring and biological sensing. Herein, long-life room-temperature phosphorescent nitrogen-doped carbon quantum dots (P-NCDs) were synthesized from triethylenetetramine hexaacetic acid via a simple one-step hydrothermal method. The P-NCDs showed high photoresponsive oxidase-like activity. On this basis, a P-NCD-based photostimulated colorimetric sensing system was developed and used to detect Hg2+ in environmental and biological samples. P-NCDs under 365 nm UV lamp irradiation converted dissolved oxygen, via triplet excited state (T1) exciton transfer, to singlet oxygen (1O2), which then oxidized 3,3′,5,5′-tetramethylbenzidine (TMB), leading to a color changing reaction. Cysteine can suppress the catalysis of P-NCDs, and its specific complexation with Hg2+ can recover the oxidation activity of P-NCDs. Hence, efficient colorimetric Hg2+ detection with a linear range of 0.01–14 μM and a detection limit of 3.1 nM was achieved by detecting the color change of TMB. The feasibility of this strategy was validated through real sample analysis. Our study broadens the application scope of phosphorescent nanomaterials into colorimetric sensing.
When using personal computing services in mixed reality (MR) such as online payment and social media, sensitive information and account passwords must be typed in MR. To design secure MR systems and build up user trust, it is imperative to first understand the security threat to the sensitive MR input. Although keystroke inference attacks by analyzing human-computer interaction in videos or via wireless signals have been successful, they require placing extra hardware near the user which is easily noticeable in practice. In this paper, we expose a more dangerous malware-based attack through the vulnerability that no permission is required for accessing MR motion data. We aim to monitor MR headset motion and infer the user input through a benign App. Realizing the attack system requires addressing unique challenges in MR such as six-degree-of-freedom (6DoF) device motion and no explicit motion signal for keystroke identification. To this end, we present HoloLogger, the first malware-based keystroke inference attack system on HoloLens. HoloLogger is empowered by a 6DoF-head-motion-driven key tracking scheme and an air-tap-pattern-based keystroke inference framework. Extensive evaluations with 25 users and 750 inference trials of passwords consisting of 4–8 lowercase English letters demonstrate that HoloLogger successfully achieves a top-5 accuracy of 93%. HoloLogger is also robust in various environments such as different user positions and input categories.
360° live video streaming is becoming increasingly popular. While providing viewers with enriched experience, 360° live video streaming is challenging to achieve since it requires a significantly higher bandwidth and a powerful computation infrastructure. A deeper understanding of this emerging system would benefit both viewers and system designers. Although prior works have extensively studied regular video streaming and 360° video on demand streaming, we for the first time investigate the performance of 360° live video streaming. We conduct a systematic measurement of YouTube's 360° live video streaming using various metrics in multiple practical settings. Our key findings suggest that viewers are advised not to live stream 4K 360° video, even when dynamic adaptive streaming over HTTP (DASH) is enabled. Instead, 1080p 360° live video can be played smoothly. However, the extremely large one-way video delay makes it only feasible for delay-tolerant broadcasting applications rather than real-time interactive applications. More importantly, we have concluded from our results that the primary design weakness of current systems lies in inefficient server processing, non-optimal rate adaptation, and conservative buffer management. Our research insight will help to build a clear understanding of today's 360° live video streaming and lay a foundation for future research on this emerging yet relatively unexplored area.
Room temperature phosphorescent quantum dots combined with molecular imprinting technology for the highly selective detection of malachite green (MG) in fish and water.