Generation Of Oxygen Radicals Research Articles

A hexanuclear Iridium(III) cluster for histidine-induced singlet oxygen and superoxide radicals generation

Photosensitizers (PSs) play key roles in photodynamic therapy (PDT). PDT is typically reliant on the local concentration of oxygen. A big challenge for PSs is to develop oxygen-independent photosensitizers, which can work well in hypoxic tumor microenvironment. In this piece of work, a hexanuclear Ir(III) cluster (Ir6) is highly selective towards histidine and histidine-rich (His-rich) proteins to form mononuclear Ir(III) complexes of [Ir(bpy)2(His)]. After the selective response to histidine or his-rich proteins, [Ir(bpy)2(His)] generates both singlet oxygen(1O2) and superoxide (O2−). This work opens an avenue for the potential application of Ir6 for type Ι and ΙΙ synergic photodynamic therapy.

Zr‐MOF Nanosheets Featuring Benzothiadiazoles Enable Efficient Visible Light Driven Photooxidation of Sulfides and Amines

AbstractUltrathin zirconium‐based metal−organic framework (MOF) nanosheets, embedded with photochromic units, are expected to be highly efficient heterogeneous photocatalysts, thanks to their rich catalytic sites, short diffusion paths, and effective separation of photogenerated charge carriers. Herein, we reported the synthesis of novel Zr‐MOF nanosheets (Zr‐BTDB) through a solvothermal synthesis that integrates benzothiadiazole (BTz) as a photochromic moiety within the framework of MOF. The Zr‐BTDB nanosheets processes a [Zr12(μ3‐O)8(μ3‐OH)8(μ2‐OH)6] cluster with hcp topology. Importantly, Zr‐BTDB nanosheets exhibit excellent photocatalytic activity for the photooxidation of sulfides and amines at room temperature under blue light irradiation. Notably, these nanosheets maintain their photocatalytic activity and selectivity for up to five cycles without significant loss of activity and crystallinity. Systematical catalytic reactions revealed that the Zr‐BTDB nanosheets enable the generation of singlet oxygen (1O2) and superoxide radical (O2⋅−) under visible light irradiation, which is critical reactive oxygen species for the photooxidation of sulfides and benzylamines. Our work represents a straightforward route for the preparation of ultrathin, water stable, and visible‐light‐activated Zr‐MOF nanosheets, offering new potentials for the selective photooxidation of sulfides and amines in an eco‐friendly way.

Roles of Cocatalysts in Biomass Photo(electro)refining

AbstractPhotosynthesis converts solar energy, carbon dioxide, and water into biomass, offering a renewable energy and chemical source. Biomass photo(electro)refining (BPeR) emerges as a sustainable alternative to petrochemicals for fuel and chemical production. However, BPeR faces challenges due to photocatalyst limitations, necessitating the integration of cocatalysts. Cocatalysts significantly impact the efficiency, selectivity, and durability of BPeR reactions, yet their roles require systematic elucidation and understanding. This review explores how cocatalysts impact the carbon bond functionalization, cleavage, and formation in biomass and its derivatives. It discusses their crucial roles in charge carrier generation, separation, and transportation, particularly in catalyzing surface reactions such as hydrogen‐involved reactions, generation, and manipulation of oxygen or carbon radicals, and the C─C/O/H bond transformations. Additionally, it outlines challenges and prospects for developing cocatalysts to enhance BPeR efficiency and durability, boosting the viability of biomass as a sustainable source of energy and materials.

Effect of interval hypoxytherapy on the immune status of hypertensive patients

In recent years, the role of sluggish nonspecific inflammation in the pathogenesis of hypertension has been proven. Oxidative stress that develops in hypertension leads to damage of endothelial glycocalyx with impaired barrier and adaptive functions of endothelium. Activation of transcription factor NF-kB leads to increased synthesis of free oxygen radicals, adhesion molecules (VCAM-1, ICAM-1, P-selectin, E-selectin) and proinflammatory cytokines (TNFα, IL-1, IL-6), triggering the inflammatory process in the endothelium. Modern antihypertensive drugs, affecting various pathogenetic mechanisms of arterial hypertension development, do not fully affect the immune component of arterial hypertension. Therefore, the search for various methods affecting the immunologic reactivity of hypertensive patients remains relevant in our time. The aim of the study was to reveal the effect of interval hypoxytherapy on the state of immunologic reactivity of patients with hypertension stage I. One hundred seventy male patients of 30-45 years old (mean age 38.36±1.64 years) with hypertension stage I (n = 170) who underwent combined treatment including drug therapy and normobaric interval hypoxic therapy in hypoxia-normoxia mode (oxygen content in hypoxic gas mixture was 20.9%) were examined. Indices of redox status and immunologic reactivity before and after interval hypoxytherapy were studied. Having a significant antioxidant effect, interval hypoxytherapy led to the subsidence of oxidative stress, which was indicated by an increase in the activity of superoxide dismutase and glutathione peroxidase in blood erythrocytes and a decrease in the content of malonic dialdehyde in blood as a result of a decrease in the generation of free oxygen radicals and suppression of lipid peroxidation processes. Interval hypoxytherapy resulted in a statistically significant increase in the initially decreased content of CD3+T lymphocytes (p 0.05), CD3+CD4+T lymphocytes (p 0.02), CD3+CD8+T lymphocytes (p 0.02). Initially increased number of B-lymphocytes CD19+, CD16+ lymphocytes, CD95+ lymphocytes significantly decreased. An important result of interval hypoxytherapy was a pronounced anti-inflammatory effect: statistically significant decrease in the content of pro-inflammatory interleukins IL-1β (p 0.02), IL-6 (p 0.01) and increase in the content of anti-inflammatory cytokines IL-4 (p 0.005) and IL-10 (p 0.005), which led to the subsidence of sluggish nonspecific inflammation. Suppression of oxidative stress and normalization of immunological reactivity of hypertensive patients after interval hypoxytherapy led to the subsidence of sluggish nonspecific inflammation, reduction of endothelial dysfunction and restoration of the structure and tone of the vascular wall with a decrease in blood pressure and improvement of the clinical course of hypertension.

Enhanced Co-Adsorption of Alcohols and Amines for Visible Light Driven Oxidative Condensation Using Iron-Based MOF.

Imines are essential intermediates in organic transformations, and is generally produced by dehydrogenative condensation of alcohols and amines with the assist of specialized catalysts and additives. Heterogeneous photocatalysis provides a sustainable platform for such process without the using of toxic oxidants, yet a functionalized photocatalyst with optimized co-adsorption of reactants needs to be developed to promote the stoichiometric oxidative condensation under ambient conditions. Here, we show that benzyl alcohol and aniline adsorb non-interferingly on the Fe node and the linker sites of the MIL-53(Fe) metal organic frameworks (MOFs), respectively. The co-adsorption of both reactants barely influences the reduction of molecular oxygen to generate oxygen radicals, resulting in efficient formation of benzaldehyde under visible light. Additionally, the weak adsorption of water together with surface acidity of the MIL-53(Fe) promote a rapid condensation of benzaldehyde with aniline and the depletion of generated water, achieving an efficient C-N bond creation for a wide range of substrates.

Sustainable electro-Fenton simultaneous reduction of Cr (VI) and degradation of organic pollutants via dual-site porous carbon cathode driving uncoordinated molybdenum sites conversion

Simultaneous removal of heavy metals and organic contaminants remains a substantial challenge in the electro-Fenton (EF) system. Herein, we propose a facile and sustainable “iron-free” EF system capable of simultaneously removing hexavalent chromium (Cr (VI)) and para-chlorophenol (4-CP). The system comprises a nitrogen-doped and carbon-deficient porous carbon (dual-site NPC-D) cathode coupled with a MoS2 nanoarray promoter (MoS2 NA). The NPC-D/MoS2 NA system exhibits exceptional synergistic electrocatalytic activity, with removal rates for Cr (VI) and 4-CP that are 20.3 and 4.4 times faster, respectively, compared to the NPC-D system. Mechanistic studies show that the dual-site structure of NPC-D cathode favors the two-electron oxygen reduction pathway with a selectivity of 81 %. Furthermore, an electric field-driven uncoordinated Mo valence state conversion of MoS2 NA enchances the generation of dynamic singlet oxygen and hydroxyl radicals. Notably, this system shows outstanding recyclability, resilience in real wastewater, and sustainability during a 3 L scale-up operation, while effectively mitigating toxicity. Overall, this study presents an effective approach for treating multiple-component wastewater and highlights the importance of structure-activity correlation in synergistic electrocatalysis.

Chlorin e6-Conjugated Mesoporous Titania Nanorods as Potential Nanoplatform for Photo-Chemotherapy.

Photodynamic therapy (PDT) has developed as an efficient strategy for cancer treatment. PDT involves the production of reactive oxygen species (ROS) by light irradiation after activating a photosensitizer (PS) in the presence of O2. PS-coupled nanomaterials offer additional advantages, as they can merge the effects of PDT with conventional enabling-combined photo-chemotherapeutics effects. In this work, mesoporous titania nanorods were surface-immobilized with Chlorin e6 (Ce6) conjugated through 3-(aminopropyl)-trimethoxysilane as a coupling agent. The mesoporous nanorods act as nano vehicles for doxorubicin delivery, and the Ce6 provides a visible light-responsive production of ROS to induce PDT. The nanomaterials were characterized by XRD, DRS, FTIR, TGA, N2 adsorption-desorption isotherms at 77 K, and TEM. The obtained materials were tested for their singlet oxygen and hydroxyl radical generation capacity using fluorescence assays. In vitro cell viability experiments with HeLa cells showed that the prepared materials are not cytotoxic in the dark, and that they exhibit photodynamic activity when irradiated with LED light (150 W m-2). Drug-loading experiments with doxorubicin (DOX) as a model chemotherapeutic drug showed that the nanostructures efficiently encapsulated DOX. The DOX-nanomaterial formulations show chemo-cytotoxic effects on Hela cells. Combined photo-chemotoxicity experiments show enhanced effects on HeLa cell viability, indicating that the conjugated nanorods are promising for use in combined therapy driven by LED light irradiation.

Release and generation of polycyclic aromatic hydrocarbons during co-pyrolysis of straw and coal: A case of corn straw and brown coal

The release of polycyclic aromatic hydrocarbons (PAHs) during the pyrolysis of corn straw, brown coal, and their mixtures was investigated in this study. The mixing ratios were the essential factor in determining the release and generation of PAHs. Adjustments to the mixing ratio revealed that the activation energy reached its nadir at a corn straw proportion of 75%. As the corn straw proportion increased, PAHs’ yield and toxic equivalents decreased. Furthermore, this study elucidated the generation of PAHs in the products by integrating experiments and reaction kinetics calculations. Low-ring and medium-ring PAHs were generated more readily, while the content of high-ring PAHs and product toxicity decreased rapidly upon adding corn straw. Finally, the high oxygen content in corn straw generates oxygen radicals that reduce the concentration of hydrocarbons and benzenes, which mitigates the generation of PAHs and enhances the quality of the resultant oil.

A Stimulus-Responsive Ternary Heterojunction Boosting Oxidative Stress, Cuproptosis for Melanoma Therapy.

Cuproptosis, a recently discovered copper-dependent cell death, presents significant potential for the development of copper-based nanoparticles to induce cuproptosis in cancer therapy. Herein, a unique ternary heterojunction, denoted as HACT, composed of core-shell Au@Cu2O nanocubes with surface-deposited Titanium Dioxide quantum dots and modified with hyaluronic acid is introduced. Compared to core-shell AC NCs, the TiO2/Au@Cu2O exhibits improved energy structure optimization, successfully separating electron-hole pairs for redox use. This optimization results in a more rapid generation of singlet oxygen and hydroxyl radicals triggering oxidative stress under ultrasound radiation. Furthermore, the HACT NCs initiate cuproptosis by Fenton-like reaction and acidic environment, leading to the sequential release of cupric and cuprous ions. This accumulation of copper induces the aggregation of lipoylated proteins and reduces iron-sulfur proteins, ultimately initiating cuproptosis. More importantly, HACT NCs show a tendency to selectively target cancer cells, thereby granting them a degree of biosecurity. This report introduces a ternary heterojunction capable of triggering both cuproptosis and oxidative stress-related combination therapy in a stimulus-responsive manner. It can energize efforts to develop effective melanoma treatment strategies using Cu-based nanoparticles through rational design.

Overcoming antibiotic resistance caused by genetic mutations of Helicobacter pylori with mucin adhesive polymer-based therapeutics

Herein, we describe the 3′-sialyllactose-polyethyleneimine-chlorine e6 conjugate (3PC), meticulously engineered to effectively target Helicobacter bacteria (H. pylori) within the gastric environment. The composition of 3PC comprises polyethyleneimine, a cationic polymer, 3′-sialyllactose, which exhibits a specific binding affinity for H. pylori surface proteins, and a photosensitizer capable of generating oxygen radicals in response to specific wavelengths. The distinctive feature of 3PC lies in its capacity to enhance interaction with the anionic mucus layer facilitated by electrostatic forces. This interaction results in prolonged residence within the intestinal environment. The extended vacation in the intestinal milieu overcomes inherent limitations that have historically impeded conventional antibiotics from efficiently reaching and targeting H. pylori. 3PC can be harnessed as a potent tool for antibacterial photodynamic therapy, and its versatility extends to addressing the challenges posed by various antibiotic-resistant strains. The exceptional efficacy of 3PC in enhancing intestinal residence time and eradicating H. pylori has been robustly substantiated in animal models, particularly in mice. In summary, 3PC is a formidable agent capable of eradicating H. pylori, irrespective of its antibiotic resistance status, by efficiently penetrating and selectively targeting the mucus layer within the gastric environment.

Quercetina inibe a liberação das armadilhas extracelulares dos neutrófilos e a atividade tóxica delas sobre células A549

Abstract Neutrophil extracellular traps (NETs) were first reported as a microbicidal strategy for activated neutrophils. Through an immunologic response against several stimuli, neutrophils release their DNA together with proteins from granules, nucleus, and cytoplasm (e.g., elastase and myeloperoxidase). To date, NETs have been implicated in tissue damage during intense inflammatory processes, mainly when their release is dependent on oxygen radical generation. Flavonoids are antioxidant and anti-inflammatory agents; of these, quercetin is commonly found in our daily diet. Therefore, quercetin could exert some protective activity against tissue damage induced by NETs. In our in vitro assays, quercetin reduced NETs, myeloperoxidase (MPO), and elastase release from neutrophils stimulated with phorbol 12-myristate 13-acetate (PMA). The activity of these enzymes also decreased in the presence of quercetin. Quercetin also reduced the cytotoxic effect of NETs on alveolar cells (A549 cell line). Further, in silico assays indicated favorable interactions between quercetin and NET proteins (MPO and elastase). Overall, our results demonstrate that quercetin decreases deleterious cellular effects of NETs by reducing their release from activated neutrophils, and diminishing the enzymatic activity of MPO and elastase, possibly through direct interaction.

Oxidized Low-Density Lipoprotein Accumulation in Macrophages Impairs Lipopolysaccharide-Induced Activation of AKT2, ATP Citrate Lyase, Acetyl-Coenzyme A Production, and Inflammatory Gene H3K27 Acetylation.

The accumulation of lipid and the formation of macrophage foam cells is a hallmark of atherosclerosis, a chronic inflammatory disease. To better understand the role of macrophage lipid accumulation in inflammation during atherogenesis, we studied early molecular events that follow the accumulation of oxidized low-density lipoprotein (oxLDL) in cultured mouse macrophages. We previously showed that oxLDL accumulation downregulates the inflammatory response in conjunction with downregulation of late-phase glycolysis. In this study, we show that within hours after LPS stimulation, macrophages with accumulated oxLDL maintain early-phase glycolysis but selectively downregulate activation of AKT2, one of three AKT isoforms. The inhibition of AKT2 activation reduced LPS-induced ATP citrate lyase activation, acetyl-CoA production, and acetylation of histone 3 lysine 27 (H3K27ac) in certain inflammatory gene promoters. In contrast to oxLDL, multiple early LPS-induced signaling pathways were inhibited in macrophages with accumulated cholesterol, including TBK1, AKT1, AKT2, MAPK, and NF-κB, and early-phase glycolysis. The selective inhibition of LPS-induced AKT2 activation was dependent on the generation of mitochondrial oxygen radicals during the accumulation of oxLDL in macrophages prior to LPS stimulation. This is consistent with increased oxidative phosphorylation, fatty acid synthesis, and oxidation pathways found by comparative transcriptomic analyses of oxLDL-loaded versus control macrophages. Our study shows a functional connection between oxLDL accumulation, inactivation of AKT2, and the inhibition of certain inflammatory genes through epigenetic changes that occur soon after LPS stimulation, independent of early-phase glycolysis.

A versatile LTF-GO/gel hydrogel with antibacterial and antioxidative attributes for skin wound healing

Skin wound healing will become a pressing and difficult problem following injury to the skin structure. Persistent wounds, in particular, become more vulnerable to bacterial infections, which can contribute to persistent skin inflammation. Therefore, it is critical to create a wound dressing that promotes wound healing while also being antimicrobial. In the present work, a multifunctional biological activity hydrogel formed by enzymatic cross-linking was developed by introducing graphene oxide (GO) and lactoferrin to gelatin hydrogel. Furthermore, by incorporating lactoferrin, the composite hydrogels exhibit excellent in vitro antibacterial and biocompatibility. According to cell experiments, the LTF-GO/Gel hydrogel can improve wound healing by enhancing L929 cell migration. Interestingly, under near-infrared light, LTF-GO/Gel hydrogel increases the generation of singlet oxygen (1O2) and hydroxyl radical (-OH), making the hydrogel system excellent antioxidant and antibacterial capabilities, these results demonstrate that the LTF-GO/Gel hydrogel has clinical promise as a wound dressing for wound healing. In vivo experiments unequivocally establish the capacity of the LTF-GO/Gel hydrogel to expedite wound healing and mitigate inflammation. This hydrogel, therefore, harbors immense potential for applications in wound healing.

Environment-friendly chemical mechanical polishing using NaHCO3-activated H2O2 slurry for highly efficient finishing of 4H-SiC (0001) surface

Silicon carbide (SiC) is recognized as one of the most promising and widely used semiconductor materials, but the current chemical mechanical polishing (CMP) process for SiC is inefficient and polluting. There is badly in need of developing an efficient and environmentally friendly CMP polishing solution for SiC. This paper proposes the use of a bicarbonate-activated hydrogen peroxide (BAP) system in SiC CMP to address the inefficiency and environmental concerns. The BAP system aims to develop an economical, environmentally friendly, efficient, and sustainable SiC CMP solution. Comparative tests were conducted to validate the material removal rate (MRR), surface roughness (Sa), and morphology of 4H-SiC samples after CMP processing. The experimental results show that the introduction of NaHCO3 induces the generation of different reactive oxygen radicals (·CO3−, ·O2−, 1O2) when combined with hydrogen peroxide (H2O2). This enhancement significantly improves the oxidation performance of the polishing solution. The average MRR after a 2-hour CMP process is measured at 220 ± 5 nm/h, which represents a remarkable 450 % increase in material removal efficiency compared to using pure H2O2 slurry. Furthermore, the surface roughness (Sa) after polishing is measured at only 0.283 ± 0.016 nm, indicating a smooth surface without noticeable scratches.

Photothermal-promoted O2/[rad]OH generation of gold nanotetrapod @ platinum nano-islands for enhanced catalytic/photodynamic therapy

Ultrasmall platinum (Pt) nanozymes are used for catalytic therapy and oxygen (O2)-dependent photodynamic therapy (PDT) by harnessing the dual-enzyme activities of catalase (CAT) and peroxidase (POD). However, their applications as nanocatalysts are limited due to their low catalytic activity. Herein, we constructed a photothermal-promoted bimetallic nanoplatform (AuNTP@Pt-IR808) by depositing ultrasmall Pt nano-islands and modifying 1-(5-Carboxypentyl)-2-(2-(3-(2-(1-(5-carboxypentyl)-3,3-dimethylindolin-2-ylidene)ethylidene)-2-chlorocyclohex-1-en-1-yl)vinyl)-3,3-dimethyl-3H-indol-1-ium bromide (IR808) on gold nanotetrapod (AuNTP) with CAT/POD activities to enhance PDT/catalytic therapy. In the tumor microenvironment, the ultrasmall Pt can catalyze endogenous hydrogen peroxide (H2O2) to produce O2, relieving tumor hypoxia and enhancing the PDT performance. Moreover, AuNTP integration into the bimetallic nanoplatform showed good electron transfer properties and promoted the POD activity of ultrasmall Pt. Importantly, AuNTP@Pt-IR808 possessed higher photothermal conversion performance than single AuNTPs, which enhanced photothermal therapy (PTT). It also accelerated the CAT/POD dual-enzyme activities, and promoted the generation of singlet oxygen (1O2) and hydroxyl radical (OH). By enhancing the performances of PTT/PDT/catalytic therapy, the developed AuNTP@Pt-IR808 nanoplatform demonstrated good antitumor efficacy against breast cancer.

Robust integration of light-driven carbon quantum dots with bacterial cellulose enables excellent mechanical and antibacterial biodegradable yarn

Due to the overuse of antimicrobial drugs, bacterial resistance became an urgent problem to be solved. In this study, carbon quantum dots (CQDs) with high photodynamic antibacterial activity were synthesized by a one-pot hydrothermal method and introduced into bacterial cellulose (BC) dispersion solution. Through a wet-spinning and wet-twisting processing strategy, bionic ordering nanocomposite macrofiber (BC/CQDs-based yarn) based on BC were obtained. The results showed that BC/CQDs-based yarn had excellent tensile strength (226.8 MPa) and elongation (22.2 %). Utilizing the light-driven generation of singlet oxygen (1O2) and hydroxyl radical (·OH), BC/CQDs-based yarn demonstrated remarkable antibacterial efficacy, with 99.9999 % (6 log, P < 0.0001) and 96.54 % (1.46 log, P < 0.0004) effectiveness against E. coli and S. aureus, respectively. At the same time, BC/CQDs-based yarn also displayed the characteristics of photothermal, fluorescent, and biodegradability. In summary, the application potential of BC/CQDs-based yarn is significant, opening up a new strategy for the development of sustainable green weaving and bio-based multi-function yarn.

Abiotic Stress in Rice: Visiting the Physiological Response and Its Tolerance Mechanisms

Rice (Oryza sativa L.) is one of the most significant staple foods worldwide. Carbohydrates, proteins, vitamins, and minerals are just a few of the many nutrients found in domesticated rice. Ensuring high and constant rice production is vital to facilitating human food supplies, as over three billion people around the globe rely on rice as their primary source of dietary intake. However, the world’s rice production and grain quality have drastically declined in recent years due to the challenges posed by global climate change and abiotic stress-related aspects, especially drought, heat, cold, salt, submergence, and heavy metal toxicity. Rice’s reduced photosynthetic efficiency results from insufficient stomatal conductance and natural damage to thylakoids and chloroplasts brought on by abiotic stressor-induced chlorosis and leaf wilting. Abiotic stress in rice farming can also cause complications with redox homeostasis, membrane peroxidation, lower seed germination, a drop in fresh and dry weight, necrosis, and tissue damage. Frequent stomatal movements, leaf rolling, generation of reactive oxygen radicals (RORs), antioxidant enzymes, induction of stress-responsive enzymes and protein-repair mechanisms, production of osmolytes, development of ion transporters, detoxifications, etc., are recorded as potent morphological, biochemical and physiological responses of rice plants under adverse abiotic stress. To develop cultivars that can withstand multiple abiotic challenges, it is necessary to understand the molecular and physiological mechanisms that contribute to the deterioration of rice quality under multiple abiotic stresses. The present review highlights the strategic defense mechanisms rice plants adopt to combat abiotic stressors that substantially affect the fundamental morphological, biochemical, and physiological mechanisms.

Edge-selective covalent passivation of black phosphorus nanosheets by fullerene C70 toward enhanced antimicrobial performance

In the fight against bacterial infection, conventional antibiotic treatment encounters the formidable challenges of drug resistance and sluggish development. Non-metallic two-dimensional (2D) nanomaterials such as black phosphorus (BP) have emerged as promising non-antibiotic antimicrobial candidates due to its peculiar physiochemical properties, but face hurdles including low ambient stability and limited antibacterial activity, hindering its widespread utilization in disinfection. Herein, few-layer BP nanosheets (BPNSs) were covalently passivated by edge-selectively grafting fullerene C70 via a one-step solid-state mechanochemical route, and for the first time the covalently functionalized BPNSs is employed in disinfection. Fullerene edge-selective covalent passivation not only effectively overcomes the obstacles of poor ambient stability, but also substantially enhances the antibacterial activities of BPNSs. The BPNSs-C70 hybrid (denoted as BPNSs-C70) was applied as a novel non-metallic and non-antibiotic nano-antibacterial agent. Under 660 nm visible light irradiation, BPNSs-C70 demonstrates high generation capacity of reactive oxygen species (ROS), resulting in boosted in vitro and in vivo antibacterial efficacies against methicillin-resistant Staphylococcus aureus (MRSA) relative to the pristine BPNSs with exceptional biocompatibility. The significantly enhanced antibacterial performance of BPNSs-C70 is attributed to the synergistically improved singlet oxygen (1O2) and hydroxyl radicals (•OH) generation originated from the intramolecular electron transfer from BPNSs to C70.

Regeneration Plate 3.0 – Improvement and Maintenance of Intestinal Health by Reduction of Oxidative Stress and Inflammation

Background: Sleep is an integral biological necessity and is understood to possess recuperative and regenerative properties. Sleep deprivation has been associated with diseases and an increase in morbidity and mortality. Several recent studies have suggested a strong relation between insufficient sleep and gastrointestinal diseases, especially when triggered by inflammatory processes. Accordingly to these findings it has been reported that sleep deprivation in both humans and experimental animals causes a progressive increase in circulating white blood cells, mainly neutrophils as well as an increase in various circulating proinflammatory molecules. Experimental: Against this background we used cultured intestinal epithelial cells to investigate the positive impact of a specially designed device, Regeneration Plate 3.0, which is positioned under the bed during sleep and is stated to improve systemic health on the cellular level by reducing oxidative stress which acts on the body. The plate produces a vital field with a frequency pool containing all important regeneration frequencies within a radius of 90 cm. The body's own energy field only resonates with those frequencies that are required for an optimal supply of energy to the cells. The field strength of the vital field is adjusted in such a way that the energy system cannot be over-energized. In addition, we also used an in vitro model with inflammation-mediating cells (= functional neutrophils) to examine whether the Regeneration Plate 3.0 might be able to reduce the generation of reactive oxygen radicals during an inflammatory process. Results: The results demonstrate that the Regeneration Plate 3.0 was able to reduce oxidative stress acting on intestinal epithelial cells. After 24 hours, the percentage of surviving cells after exposure to 2 mM hydrogen peroxide and the Regeneration Plate 3.0 for 8 hours was 27.7 ± 5.7%, while the viability of the untreated control cells was 14.7 ± 2.9% (mean values ± standard deviations). The difference between both experimental groups was statistically highly significant at the p ≤ 0.01 level. Moreover, the generation of superoxide anion radicals by functional neutrophils was reduced by nearly 50% in comparison to untreated control cells. Again, the difference between both groups was statistically highly significant at the p ≤ 0.01 level. Conclusions: Both beneficial effects of the Regeneration Plate 3.0 shown in the present in vitro study can act on the body during sleep and might enhance not only intestinal health, but also systemic health and well-being.

Extracellular polymeric substances altered the physicochemical properties of molybdenum disulfide nanomaterials to mitigate its toxicity to Chlorella vulgaris

Although the toxic effects of two-dimensional nanomaterials (2D-NMs) have been widely reported, the influence of extracellular polymeric substances (EPS) on the environmental fate and risk of 2D-NMs in aquatic environments is largely unknown, and the processes and mechanisms involved remain to be revealed. Herein, we investigated the impact of EPS secreted by microalgae (Chlorella vulgaris (C. vulgaris)) on the environmental transformation and risk of molybdenum disulfide (MoS2). We found that the attachment of EPS increased the thickness of MoS2 (from 2 nm to 5 nm), changed it from a monolayer sheet to a fuzzy multilayer structure, and promoted the formation of defects on MoS2. The blue-shift of the peak associated with the plasmon resonances in the 1 T phase and the generation of electron-hole pairs suggested that EPS altered the surface electronic structure of MoS2. EPS interacted mainly with the S atoms on the 1 T phase, and the attachment of EPS promoted the oxidation of MoS2. The reduction in hydrodynamic diameter (Dh) and the decrease in zeta potential indicated that EPS inhibited the agglomeration behavior of MoS2 and enhanced its dispersion and stability in aqueous media. Notably, EPS reduced the generation of free radicals (superoxide anion (•O2−), singlet oxygen (1O2), and hydroxyl radicals (•OH−)). Furthermore, EPS mitigated the toxicity of MoS2 to C. vulgaris, such as attenuated reduction in biomass and chlorophyll content. Compared to pristine MoS2, MoS2 + BG11 + EPS exhibited weaker oxidative stress, membrane damage and lipid peroxidation. The adsorption of EPS on MoS2 surface reduced the attachment sites of MoS2, making MoS2 less likely to be enriched on the cell surface. The findings have significant contribution for understanding the interactions between EPS and MoS2 in aquatic ecosystems, providing scientific guidance for risk assessment of 2D-NMs.