Adsorption is essential for many processes on surfaces; therefore, an accurate prediction of adsorption properties is demanded from both fundamental and technological points of view. Particularly, ...identifying the intrinsic determinants of adsorption energy has been a long-term goal in surface science. Herein, we propose a predictive model for quantitative determination of the adsorption energies of small molecules on metallic materials and oxides, by using a linear combination of the valence and electronegativity of surface atoms and the coordination of active sites, with the corresponding prefactors determined by the valence of adsorbates. This model quantifies the effect of the intrinsic properties of adsorbates and substrates on adsorbate-substrate bonding, derives naturally the well-known adsorption-energy scaling relations, and accounts for the efficiency and limitation of engineering the adsorption energy and reaction energy. All involved parameters are predictable and thus allow the rapid rational design of materials with optimal adsorption properties.
Combinatory modulation of the physical and biochemical characteristics of nanocarrier delivery systems is an emergent topic in the field of nanomedicine. Here, we studied the combined effects of ...incorporation of active targeting moieties into nanocarriers and their morphology affecting the enhanced permeation and retention effect for nanomedicine cancer therapy. Self-assembled lipid discoidal and vesicular nanoparticles with low-polydispersity sub-50 nm size range and identical chemical compositions were synthesized, characterized, and correlated with in vitro cancer cellular internalization, in vivo tumor accumulation and cancer treatments. The fact that folate-associated bicelle yields the best outcome is indicative of the preference for discoidal carriers over spherical carriers and the improved targeting efficacy due to the targeting ligand/receptor binding. The approach is successfully adopted to design the nanocarriers for photodynamic therapy, which yields a consistent trend in in vitro and in vivo efficacy: folate nanodiscs > folate vesicles > nonfolate nanodiscs > nonfolate vesicles. Folate discs not only have shown a higher tumor uptake and photothermal therapeutic efficiency, but also minimize skin photosensitivity side effects. The advantages of nanodiscoidal bicelles as nanocarriers, including well-defined size, robust formation, easy encapsulation of hydrophobic molecules (therapeutics and/or diagnostics), easy incorporation of targeting molecules, and low toxicity, enable the scalable manufacturing of a generalized in vivo multimodal delivery platform.
The controlled size and surface treatment of magnetic nanoparticles (NPs) make one‐stage combination feasible for enhanced magnetic resonance imaging (MRI) contrast and effective hyperthermia. ...However, superparamagnetic behavior, essential for avoiding the aggregation of magnetic NPs, substantially limits their performance. Here, a superparamagnetic core–shell structure is developed, which promotes the formation of vortex‐like intraparticle magnetization structures in the remanent state, leading to reduced dipolar interactions between two neighboring NPs, while during an MRI scan, the presence of a DC magnetic field induces the formation of NP chains, introducing increased local inhomogeneous dipole fields that enhance relaxivity. The core–shell NPs also reveal an augmented anisotropy, due to exchange coupling to the high anisotropy core, which enhances the specific absorption rate. This in vivo tumor study reveals that the tumor cells can be clearly diagnosed during an MRI scan and the tumor size is substantially reduced through hyperthermia therapy by using the same FePt@iron oxide nanoparticles, realizing the concept of theranostics.
The magnetic interaction among nanoparticles is demonstrated to be able to be manipulated by a core–shell structure to enhance the resolution of magnetic resonance imaging and the specific absorption rate of nanoparticles. It is rather remarkable that the magnetic configuration of the assembly shape can be controlled under a magnetic field toimprove the relaxivity of the contrast agent and the effectiveness of hyperthermia, making theranostics feasible.
The present study examined the relationship between physical exercise and social anxiety by testing a moderated mediation model that focused on how peer relationships mediate the relationship between ...physical exercise and social anxiety and how flow experience moderates this mediated relationship. A total of 1056 middle school students from six middle schools in Sichuan, China, volunteered to complete questionnaires comprising the Physical Activity Rating Scale, Student Peer Relationship Scale, Social Anxiety Subscale of the Self-Consciousness Scale, and Short (9-Item) Dispositional Flow Scales. Regression analysis indicated that physical exercise negatively influenced social anxiety through peer relationships (indirect effect = -0.04, 95% CI = -0.067, -0.013). In addition, a moderated regression analysis indicated that under high-flow experience, physical exercise suppresses social anxiety through positive effects on peer relationships (indirect effect = -0.04, 95% CI = -0.087, -0.003), and under low-flow experience, physical exercise exacerbates social anxiety through negative effects on peer relationships (indirect effect = 0.06, 95% CI = 0.016, 0.105). Some practical implications have been discussed on the physical exercise intervention for suppressing social anxiety in middle school students.
The mechanism of hepatoprotective compounds is usually related to its antioxidant or anti-inflammatory effects. Black garlic is produced from garlic by heat treatment and its anti-inflammatory ...activity has been previously reported. Therefore, the aim of this study was to investigate the hepatoprotective effect of five different extracts of black garlic against carbon tetrachloride (CCl₄)-induced acute hepatic injury (AHI). In this study, mice in the control, CCl₄, silymarin, and black garlic groups were orally administered distilled water, silymarin, and different fraction extracts of black garlic, respectively, after CCl₄ was injected intraperitoneally to induce AHI. The results revealed that the
-butanol layer extract (BA) and water layer extract (WS) demonstrated a hepatoprotective effect by reducing the levels of alanine aminotransferase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), and hepatic malondialdehyde (MDA). Furthermore, the BA and WS fractions of black garlic extract increased the activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione reductase (GSH-Rd), tumor necrosis factor alpha (TNF-α), and the interleukin-1 (IL-1β) level in liver. It was concluded that black garlic exhibited significant protective effects on CCl₄-induced acute hepatic injury.
Marine chitins (MC) have been utilized for the production of vast array of bioactive products, including chitooligomers, chitinase, chitosanase, antioxidants, anti-NO, and antidiabetic compounds. The ...aim of this study is the bioprocessing of MC into a potent anticancer compound, prodigiosin (PG), via microbial fermentation. This bioactive compound was produced by
TKU011 with the highest yield of 4.62 mg/mL at the optimal conditions of liquid medium with initial pH of 5.65-6.15 containing 1% α-chitin, 0.6% casein, 0.05% K
HPO
, and 0.1% CaSO
. Fermentation was kept at 25 °C for 2 d. Notably, α-chitin was newly investigated as the major potential material for PG production via fermentation; the salt CaSO
was also found to play the key role in the enhancement of PG yield of
fermentation for the first time. PG was qualified and identified based on specific UV, MALDI-TOF MS analysis. In the biological activity tests, purified PG demonstrated potent anticancer activities against A549, Hep G2, MCF-7, and WiDr with the IC
values of 0.06, 0.04, 0.04, and 0.2 µg/mL, respectively. Mytomycin C, a commercial anti-cancer compound was also tested for comparison purpose, showing weaker activity with the IC
values of 0.11, 0.1, 0.14, and 0.15 µg/mL, respectively. As such, purified PG displayed higher 2.75-fold, 1.67-fold, and 3.25-fold efficacy than Mytomycin C against MCF-7, A549, and Hep G2, respectively. The results suggest that marine chitins are valuable sources for production of prodigiosin, a potential candidate for cancer drugs.
Nanomaterials and nanoparticles have received considerable attention recently because of their unique properties and diverse biotechnology and life sciences applications. Nanosilver products, which ...have well-known antimicrobial properties, have been used extensively in a range of medical settings. Despite the widespread use of nanosilver products, relatively few studies have been undertaken to determine the biological effects of nanosilver exposure. The purpose of this study was to evaluate the toxicity of nanosilver and to elucidate possible molecular mechanisms underlying the biological effects of nanosilver. Here, we show that nanosilver is cytotoxic, inducing apoptosis in NIH3T3 fibroblast cells. Treatment with nanosilver induced the release of cytochrome
c into the cytosol and translocation of Bax to mitochondria, indicating that nanosilver-mediated apoptosis is mitochondria-dependent. Nanosilver-induced apoptosis was associated with the generation of reactive oxygen species (ROS) and JNK activation, and inhibition of either ROS or JNK attenuated nanosilver-induced apoptosis. In nanosilver-resistant HCT116 cells, up-regulation of the anti-apoptotic proteins, Bcl-2 appeared to be associated with a diminished apoptotic response. Taken together, our results provide the first evidence for a molecular mechanism of nanosilver cytotoxicity, showing that nanosilver acts through ROS and JNK to induce apoptosis via the mitochondrial pathway.
Physical exercise is crucial to the development of students' physical and mental health. This study explored the relationship between live sports learning and college students' exercise behaviors, ...and the mediating roles of exercise motivation and exercise commitment, aiming to provide theoretical bases for the future that explain the mechanism of live sports learning in exercise behaviors, as well as practical guidance for the promotion of positive physical exercise behaviors in college students. In total, 1189 college students from China volunteered to complete questionnaires. The results showed that live sports learning positively predicted college students' exercise behavior and that live sports learning was able to affect exercise behavior through the mediating roles of exercise motivation and exercise commitment, with specific mediating paths including the two independent mediating paths and a serial mediating path of exercise motivation and exercise commitment. This study confirmed, for the first time, on live sports learning in the process of promoting exercise behavior. It is suggested that educators instruct college students to regulate their participation in live sports learning and to cultivate healthy exercise motivation and exercise commitment, which is an effective way to facilitate college students' practice of physical activity.
Different emotional states lead to distinct behavioural consequences even when faced with the same challenging events. Emotions affect learning and memory capacities, but the underlying ...neurobiological mechanisms remain elusive. Here we establish models of learned helplessness (LHL) and learned hopefulness (LHF) by exposing animals to inescapable foot shocks or with anticipated avoidance trainings. The LHF animals show spatial memory potentiation with excitatory monosynaptic upscaling between posterior basolateral amygdale (BLP) and ventral hippocampal CA1 (vCA1), whereas the LHL show memory deficits with an attenuated BLP-vCA1 connection. Optogenetic disruption of BLP-vCA1 inputs abolishes the effects of LHF and impairs synaptic plasticity. By contrast, targeted BLP-vCA1 stimulation rescues the LHL-induced memory deficits and mimics the effects of LHF. BLP-vCA1 stimulation increases synaptic transmission and dendritic plasticity with the upregulation of CREB and intrasynaptic AMPA receptors in CA1. These findings indicate that opposite excitatory monosynaptic scaling of BLP-vCA1 controls LHF- and LHL-modulated spatial memory, revealing circuit-specific mechanisms linking emotions to memory.
Abstract Photodynamic therapy (PDT) is an innovative method for cancer treatment that involves the administration of a photosensitizing agent followed by exposure to visible light. An appreciable ...amount of a particular light source is a key to activate photosensitizers in PDT. However, the external excitation light source is a problem for clinical application because of the limitation of tissue-penetrating properties. Additionally, the wavelength of laser emission should match the absorption wavelength of each photosensitizer for efficient generation of reactive oxygen species and cell killing. In this study, Renilla luciferase-immobilized quantum dots-655 (QD-RLuc8) was used for bioluminescence resonance energy transfer (BRET)-mediated PDT to resolve these problems. The bioluminescent QD-RLuc8 conjugate exhibits self-illumination at 655 nm after coelenterazine addition, which can activate the photosensitizer, Foscan® -loaded micelles for PDT. Our results show that BRET-mediated PDT by QD-RLuc8 plus coelenterazine (20 μg/mL) successfully generated reactive oxygen species (40.8%), killed ∼ 50% A549 cells at 2 μg/mL equivalent Foscan® in vitro and significantly delayed tumor growth in vivo due to cell apoptosis under TUNEL analysis without obvious weight loss. Based on immunohistochemical observations, the proliferating cell nuclear antigen (PCNA)-negative area of tumor sections after BRET-mediated PDT was obviously increased compared to the PDT-untreated groups without an external light source. We conclude that this nanotechnology-based PDT possesses several clinical benefits, such as overcoming light penetration issues and treating deeper lesions that are intractable by PDT alone.
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