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Diagnosis of oxidative stress is essential to avoiding serious life-threatening situations. Hydrogen peroxide (H2O2) is a potential biomarker of oxidative stress. Herein, we introduce a reagent-free nanoscale approach for the colorimetric detection of urinary H2O2 utilizing dextran-gold nanoparticles (dAuNPs). The plasmonic properties of these nanoparticles are central to their function, leveraging their high surface area and tunable optical characteristics for sensitive detection. We transformed the colloidal dAuNPs solution into two formats: as a tablet (dAuNPs-Tablet) or impregnated on a cotton swab (dAuNPs-Swab). The assay generates a hydroxyl radical (•OH) from H2O2 via the Fenton reaction, followed by nanoscale-driven detection of H2O2 using a plasmonic tablet and swab sensors. In the presence of H2O2 in a sample, the red color of the tablet solution or plasmonic swab turns to blue due to salt-induced nanoparticles aggregation. The transition in color is observed due to •OH-assisted degradation of the dextran layer around dAuNPs, leading to the loss of colloidal stability and subsequent aggregation of dAuNPs. Sodium chloride acts as the aggregating agent, enhancing the nanoscale interactions. The detection limit in artificial urine is found to be 50 μM for the tablet sensor and 100 μM for the swab sensor. The plasmonic tablet is more stable as compared to a plasmonic swab which gradually loses stability, after one month, with approximately 40% degradation within three months. Interference studies demonstrate the high selectivity of both platforms for H2O2 detection. Notably, we investigated the H2O2 levels in human urine samples from healthy volunteers (both female and male) before and after green tea consumption. The observed decrease in the H2O2 level in urine postgreen tea consumption suggests a potential role of green tea antioxidants in mitigating oxidative stress. The utilization of nanoprobes in our research not only enhances our understanding of oxidative stress dynamics but also drives advancements in point-of-care detection platforms, offering enhanced portability and ease of use of nanoprobes. These platforms open exciting avenues in healthcare diagnosis. [ABSTRACT FROM AUTHOR]

We have developed a new type of nanoparticles with potent antitumor activity photoactivatable via the combination of molecular photoswitching of spiropyran (SP) and enzymatic reaction of glucose oxidase (GOx). As two key processes involved therein, Fe(III)‐to‐Fe(II) photoreduction in Fe(III) metal–organic frameworks (MOFs) brings about the release of free Fe2+/Fe3+ while the photoswitching of SP to merocyanine (MC) unlocks the enzymatic activity of GOx that was pre‐passivated by SP. The release of free Fe3+ boosts its hydrolysis and therefore enables the acidification of microenvironment, which is further reinforced by one of the products of the GOx‐mediated glucose oxidation reaction, gluconic acid (GlcA). Based on the generation of Fe2+ and acidic milieu together with another product of the oxidation reaction, hydrogen peroxide (H2O2), these two processes jointly present triple enabling factors for generating lethal hydroxyl radicals (⋅OH) species via Fenton reactions and therefore oxidative stress capable of inhibiting tumor. The antitumor potency of such nanoparticle is verified in tumor‐bearing model mice in vivo, proclaiming its potential as a potent and safe agent based on the unique mechanism of optically manipulating enzyme activity for synergistic antitumor therapeutics with high spatial precision, enhanced efficacy and minimized side effects. [ABSTRACT FROM AUTHOR]

Contact Electro‐Catalysis (CEC) using commercial dielectric materials in contact‐separation cycles with water can trigger interfacial electron transfer and induce the generation of reactive oxygen species (ROS). However, the inherent hydrophobicity of commercial dielectric materials limits the effective reaction sites, and the generated ROS inevitably undergo self‐combination to form hydrogen peroxide (H2O2). In typical CEC systems, H2O2 does not further decompose into ROS, leading to suboptimal reaction rates. Addressing the generation and activation of H2O2 is therefore crucial for advancing CEC. Here, we synthesized a catalyst by loading the dielectric material polytetrafluoroethylene (PTFE) onto ZSM‐5 (PTFE/ZSM‐5, PZ for short), achieving uniform dispersion of the catalyst in water for the first time. The introduction of an FeIII‐initiated self‐cycling Fenton system (SF‐CEC), with the synergistic effects of O2 activation and FeIII‐activated H2O2, further enhanced ROS generation. In the FeIII‐initiated SF‐CEC system, the synergistic effects of ROS and protonated azo dyes enabled nearly 99 % degradation of azo dyes within 10 minutes, a sixfold improvement compared to the CEC system. This represents the fastest degradation rate of methyl orange dye induced by ultrasound to date. Without extra oxidants, this system enabled stable dissolution of precious metals in weakly acidic solutions at room temperature, achieving 80 % gold dissolution within 2 hours, 2.5 times faster than similar CEC systems. This study also corrects the unfavorable perception of CEC applications under acidic conditions, providing new insights for the fields of dye degradation and precious metal recovery. [ABSTRACT FROM AUTHOR]

In the Fenton process, the development of catalysts with a wide pH range and good stability has been a long‐term goal for water treatment purpose. This study proposes a strategy to solve this problem by preparing supported catalysts CuOx@CeO2‐IE using an ion exchange reversed loading method. The generation of a large number of interfacial oxygen vacancies with Cu‐OV‐Ce (OV represents an oxygen vacancy site) structures prolongs the O−O bond of H2O2, promotes the rupture of the peroxide bond of H2O2, and thereby promotes the activation of H2O2 on the surface of the catalyst. The results show that with a H2O2 concentration of 5 mM and CuOx@CeO2‐IE at 50 mg/L, the removal rate of bisphenol A is 94.1 % in 60 min, in which • OH dominates the degradation process. Moreover, the system can operate well within a relatively wide pH range (4–8). This study provides a novel strategy for the design of Fenton catalysts with a wide pH suitability and excellent stability. [ABSTRACT FROM AUTHOR]

While hydroxyl radical is commonly named as the Fenton product responsible for DNA and RNA damage in cells, here we demonstrate that the cellular reaction generates carbonate radical anion due to physiological bicarbonate levels. In human and Escherichia coli models, their transcriptomes were analyzed by RNA direct nanopore sequencing of ribosomal RNA and chromatography coupled to electrochemical detection to quantify oxidation products in order to follow the bicarbonate dependency in H2O2-induced oxidation. These transcriptomic studies identified physiologically relevant levels of bicarbonate focused oxidation on the guanine base favorably yielding 8-oxo-7,8-dihydroguanine (OG). In human cells, the bicarbonate-dependent oxidation was further analyzed in the metabolome by mass spectrometry, and a glycosylase-dependent qPCR assay to quantify oxidation sites in telomeres. These analyses further identify guanine as the site of oxidation when bicarbonate is present upon H2O2 exposure. Labile iron as the catalyst for forming carbonate radical anion was demonstrated by repeating the bicarbonate-dependent oxidations in cells experiencing ferroptosis, which had a >fivefold increase in redox-active iron, to find enhanced overall guanine-specific oxidation when bicarbonate was present. The complete profiling of nucleic acid oxidation in the genome, transcriptome, and metabolome supports the conclusion that a cellular Fe(II)-carbonate complex redirects the Fenton reaction to yield carbonate radical anion. Focusing H2O2-induced oxidative modification on one pathway is consistent with the highly evolved base excision repair suite of enzymes to locate G-oxidation sites for repair and gene regulation in response to oxidative stress. [ABSTRACT FROM AUTHOR]

Accurate identification and functional annotation of splicing isoforms and non-coding RNAs (lncRNAs), alongside full-length protein-encoding transcripts, are critical for understanding gene (mis)regulation and metabolic reprogramming in Alzheimer's disease (AD). This study aims to provide a comprehensive and accurate transcriptome resource to improve existing AD transcript databases. Background/Objectives: Gene mis-regulation and metabolic reprogramming play a key role in AD, yet existing transcript databases lack accurate and comprehensive identification of splicing isoforms and lncRNAs. This study aims to generate a refined transcriptome dataset, expanding the understanding of AD onset and progression. Methods: Publicly available RNA-seq data from pre-AD and AD tissues were utilized. Advanced bioinformatics tools were applied to assemble and annotate full-length transcripts, including splicing isoforms and lncRNAs, with an emphasis on correcting errors and enhancing annotation accuracy. Results: A significantly improved transcriptome dataset was generated, which includes detailed annotations of splicing isoforms and lncRNAs. This dataset expands the scope of existing AD transcript databases and provides new insights into the molecular mechanisms underlying AD. The findings demonstrate that the refined dataset captures more relevant details about AD progression compared to publicly available data. Conclusions: The newly developed transcriptome resource and the associated analysis tools offer a valuable contribution to AD research, providing deeper insights into the disease's molecular mechanisms. This work supports future research into gene regulation and metabolic reprogramming in AD and serves as a foundation for exploring novel therapeutic targets. [ABSTRACT FROM AUTHOR]

Food processing industries generate complex effluent with high levels of organic and inorganic contaminants. Without proper treatment, significant operational, environmental, and public health issues may arise. This study aimed to assess the Fenton reaction's efficacy as an advanced oxidation process (AOP), to treat mixed dairy and slaughterhouse effluent from Nablus city. Bench-scale tests showed inadequate results (45.2% COD removal) because of high pollution levels (COD: 15400 -18,100 mg L−1). Further tests have combined the Fenton process with three pre-treatment methods: (A) coagulant addition, (B) settling, and (C) flocculent application. Fenton's process with flocculent achieved significant removal of organic (88.4% COD; 84.1% TKN) and inorganic (91.0% TSS; 62.4% TS) contaminants under optimised conditions (H2O2/COD ratio 2:1, H2O2/Fe + 2 ratio 10:1, pH = 3). Treated wastewater from trial (C) let meeting local regulatory standards with COD levels below 2,000 mg/l. [ABSTRACT FROM AUTHOR]

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Atherosclerosis (AS) is a growing global health epidemic and is the leading cause of cardiovascular health problems, including ischemic stroke, coronary artery disease, and peripheral vascular disease. Despite extensive research on the underlying mechanisms of AS, iron remains an under-investigated mediator in the atherosclerotic process. Iron’s involvement in AS is primarily linked to the iron-induced programmed cell death process known as ferroptosis. Ferroptosis is initiated in endothelial cells when iron overload triggers the Fenton reaction, resulting in the production of reactive oxygen species (ROS) and lipid peroxides. This oxidative stress damages cellular components, ultimately leading to cell death. The review examines the role of iron overload and ferroptosis in the progression and instability of atherosclerotic plaques. Additionally, we explore the potential therapeutic roles of iron chelators and ROS scavengers in mitigating the adverse effects of ferroptosis. The findings indicate that ferroptosis contributes significantly to the progression and instability of atherosclerotic plaques by promoting oxidative damage and cellular dysfunction. Iron chelators and ROS scavengers have shown promise in reducing ferroptosis-induced damage in endothelial cells. These therapeutic agents can potentially stabilize atherosclerotic plaques and prevent the progression of AS. Ferroptosis is a critical yet under-explored pathway in the development and progression of atherosclerosis. Targeting iron-induced oxidative stress through iron chelation and ROS scavenging presents a promising therapeutic strategy for mitigating the adverse effects of ferroptosis on atherosclerotic plaque stability. Further research is needed to validate these therapeutic approaches and better understand the molecular mechanisms underlying ferroptosis in atherosclerosis. [ABSTRACT FROM AUTHOR]

There has been recent interest in trying to understand the connection between transfer RNA (tRNA) posttranscriptional modifications and changes in-cellular environmental conditions. Here, we report on the identification of the modified nucleoside 5-methylcytidine (m5C) in Escherichia coli tRNAs. This modification was determined to be present at position 49 of tRNA Tyr-QUA- II. Moreover, m5C levels in this tRNA are significantly elevated under high reactive oxygen specieis (ROS) conditions in E. coli cells. We identified the known ribosomal RNA methyltransferase rsmF as the enzyme responsible for m5C synthesis in tRNA and enzyme transcript levels are responsive to elevated levels of ROS in the cell. We further find that changes in m5C levels in this tRNA are not specific to Fenton-like reaction conditions elevating ROS, but heat shock can also induce increased modification of tRNA Tyr-QUA- II. Altogether, this work illustrates how cells adapt to changing environmental conditions through variations in tRNA modification profiles. [ABSTRACT FROM AUTHOR]

The current study investigating the preparation and application of a Multiferroic nano-scale silver zinc ferrite substance (Ag0.5Zn0.5Fe2O4 nanocatalyst) has been established. Multiferroic silver zinc ferrite substance is prepared by co-precipitation technique as hybridized composite. This synethsized nanoparticles was characterized via X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) as well as Scanning Electron Miscospopy (SEM). Such nanoparticles are used as a sustainable recyclable photo-Fenton's reagent precursor for treating insecticide in wastewater. The results revealed a high Acinate oxidation rate reached to 97% removal within 40 min of irradiance time. To increase the performance, the operating variables are optimized. pH 3.0 and 40 and 400 mg/L for Ag0.5Zn0.5Fe2O4 and hydrogen peroxide, respectively are identified as the optimum values. Also, kinetics and thermodynamic are evaluated and the reaction is subsequent the first-order kinetics model and exothermic and non-spontaneous in nature with a low energy barrier of 35.02 kJ/mol. The advantage of Ag0.5Zn0.5Fe2O4 catalyst is its sustainability since it recovered for multiple reuse with a high activity reached to 80% removal rate after six cyclic use compared to 97% of fresh catalyst use. [ABSTRACT FROM AUTHOR]

Artemisia spp. plants are known as producers of bioactive compounds and used both in folk and traditional medicine. They possess antitumor, antiproliferative, antidiabetic, antimicrobial, antiviral, antioxidant, and anti-inflammatory activity. Aim. Because these plants exhibit antioxidant activity, it is of interest to investigate the possibility of using extracts from mugwort to prevent DNA damage initiated by some reactive oxygen species. Methods. In this work, extracts from transformed roots of Artemisia vulgaris and A. tilesii were used to study their DNA protective activity. The extracts were prepared according to standard procedure. Total flavonoid content was quantified by the modified spectrophotometric method in rutin equivalent using the calibration curve. The antioxidant activity of the extracts was determined using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH). It was evaluated by the half maximal effective concentration (EC50) calculated as the dry root weight needed for scavenging 50% of DPPH in the sample and expressed as mg DW. To calculate this value, linear regression was applied to the linear interval of radical scavenging activity. DNA protective activity was studied by the Fenton reaction assay. Results. Differences in the content of flavonoids in A. vulgaris “hairy” roots and control roots were found. For hairy roots this parameter ranged from 75.89 ± 2.32 to 126.04 ± 5.37 mg RE/g DW, which is 1.45–2.41 times more than in the control roots. Flavonoid content in A. tilesii hairy root line also differed from the control. It was 74.52 ± 0.96 … 107.8 ± 5.98 mg RE/g DW in root lines and 28,6 ± 2,11 mg/g DW in A. tilesii control roots. The level of antioxidant activity studied in the reaction with DPPH (EC50, effective concentration) was more significant in the extracts of hairy roots of both plant species. It varied from 0.16 to 0.33 and 0.17 to 0.31 in hairy root lines of A. vulgaris and A. tilesii, respectively. In comparison, this parameter reached 0.44 and 0.65 in the control roots. Adding the extracts to the reaction mixture in the Fenton reaction has some protective effects. At the same time, there were no significant differences in the degree of protection of plasmid DNA from damage (percentage of supercoiled DNA) when extracts from hairy root lines of A. vulgaris and A. tilesii were added to the reaction mixture. However, these extracts differed in the content of flavonoids and had a higher ability to scavenge DPPH radicals. Conclusions. The extracts of A. vulgaris and A. tilesii hairy roots had contained a higher content of flavonoids and had higher antioxidant activity compared to the extracts from the control roots. However, they differed little in their ability to protect DNA from damage in the Fenton reaction. Likely, that not only flavonoids, but also other components of extracts from wormwood hairy roots are involved in this process. [ABSTRACT FROM AUTHOR]

A chemiluminescence technique was used to establish that, in contrast to TiO2 photocatalysts, TiO2:MoO3 composite photocatalysts suppress the photogeneration of superoxide ions, while the capture of photoelectrons in the MoO3 phase to give reduced Mo(V) states creates conditions for the long-term generation of hydrogen peroxide capable of acting as a biocide. The TiO2:MoO3 accumulating photocatalysts were shown to be fully reusable and the cycle of photocharging followed hydrogen peroxide generation can be repeated multiple times. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide–based Fenton reaction can effectively degrade many small-molecule fluorescent dyes, leading to notable alterations in fluorescence signals. Additionally, the two-dimensional black phosphorus/platinum nanocomposite (BP/Pt) demonstrates exceptional catalase (CAT) characteristics. Based on these, a colorimetric-fluorescence dual-mode signal output pattern based on BP/Pt-Fenton reaction-rhodamine B tandem reaction system is reported. The physical adsorption property of the BP/Pt nanozymes was utilized to couple with antibodies, thus constructing a novel dual-mode nanozyme-based immuno-sensing assay (NISA). By using the migratory antibiotic enrofloxacin (ENR) as the target, the NISA provided highly sensitive detection with the detection limits of 0.058 ng/mL for colorimetric-mode and 0.025 ng/mL for fluorescence-mode and achieved accurate quantitative detection in environmental water and crucian carp samples. This work provides an innovative design for monitoring antibiotics in the environment and broadens the idea for the application of nanozymes and Fenton systems in immunosensing assays. [ABSTRACT FROM AUTHOR]

Qingcheng Song,1,2,* Yiran Zhang,3,* Hongzhi Hu,4,* Xuemei Yang,5 Xin Xing,1,2 Jianhua Wu,6 Yanbin Zhu,1,2 Yingze Zhang1,2 1Department of Orthopaedic Surgery, Third Hospital of Hebei Medical University, Shijiazhuang, Hebei, People’s Republic of China; 2Orthopaedic Institution of Hebei Province, Shijiazhuang, Hebei, People’s Republic of China; 3School of Medicine, Nankai University, Tianjin, People’s Republic of China; 4Department of Orthopedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People’s Republic of China; 5The Fourth Hospital of Shijiazhuang, Shijiazhuang, Hebei, People’s Republic of China; 6The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yingze Zhang; Yanbin Zhu, Email yzling_liu@163.com; 38600312@hebmu.edu.cnIntroduction: Ferroptosis-driven tumor ablation strategies based on nanotechnology could be achieved by elevating intracellular iron levels or inhibiting glutathione peroxidase 4 (GPX4) activity. However, the intracellular antioxidative defense mechanisms endow tumor cells with ferroptosis resistance capacity. The purpose of this study was to develop a synergistic therapeutic platform to enhance the efficacy of ferroptosis-based tumor therapy.Methods: In this study, a multifunctional nano-catalytic therapeutic platform (mFeB@PDA-FA) based on chemodynamic therapy (CDT) and photothermal therapy (PTT) was developed to effectively trigger ferroptosis in tumor. In our work, iron-based mesoporous Fe3O4 nanoparticles (mFe3O4 NPs) were employed for the encapsulation of L-buthionine sulfoximine (BSO), followed by the modification of folic acid-functionalized polydopamine (PDA) coating on the periphery. Then, the antitumor effect of mFeB@PDA-FA NPs was evaluated using Human OS cells (MNNG/HOS) and a subcutaneous xenograft model of osteosarcoma.Results: mFe3O4 harboring multivalent elements (Fe2+/3+) could catalyze hydrogen peroxide (H2O2) into highly cytotoxic ˙OH, while the tumor microenvironment (TME)-responsive released BSO molecules inhibit the biosynthesis of GSH, thus achieving the deactivation of GPX4 and the enhancement of ferroptosis. Moreover, thanks to the remarkable photothermal conversion performance of mFe3O4 and PDA shell, PTT further synergistically enhanced the efficacy of CDT and facilitated ferroptosis. Both in vivo and in vitro experiments confirmed that this synergistic therapy could achieve excellent tumor inhibition effects.Conclusion: The nanotherapeutic platform mFeB@PDA-FA could effectively disrupted the redox homeostasis in tumor cells for boosting ferroptosis through the combination of CDT, PTT and GSH elimination, which provided a new perspective for the treatment of ferroptosis sensitive tumors. Keywords: ferroptosis, chemodynamic therapy, photothermal therapy, Fenton reaction, BSO

The hypoxic environment of deep tissue and the weak energy of microwave (MW) are still the major limitations of MW catalytic therapy. In this work, an MW‐responsive nano‐platform consisting of an Mn‐doped porphyrin metal–organic framework loaded with calcium peroxide (Mn0.1PCC) is designed to regulate the microenvironment of the injection site and enhance the generation of reactive oxygen species. The excellent MW absorbing properties of Mn0.1PCC improve the Fenton reaction between hydrogen peroxide formed by the hydrolysis of calcium peroxide and released Mn2+ generating more hydroxyl radicals under MW. This process does not consume the oxygen substrate and even produces oxygen to improve the hypoxic environment. Therefore, at a low and safe concentration (125 µg mL−1), the antibacterial rate of Mn0.1PCC against 4 × 108 CFU mL−1 of methicillin‐resistant Staphylococcus aureus (MRSA) after MW irradiation for 15 min is 99.71% ± 0.18%. Mn0.1PCC, upon exposure to MW, prevents the recurrence of bacterial infections and overcomes drug resistance by inhibiting quorum sensing and the two‐component system of MRSA. It can also induce macrophage M1 polarization, up‐regulate the pro‐inflammatory factor tumor necrosis factor‐α, and enhance the phagocytosis of macrophage to bacteria. This strategy provides insights into the development of high‐performance MW‐responsive nanocomposites for the treatment of infections in deep tissues. [ABSTRACT FROM AUTHOR]

The present study was performed to evaluate the therapeutic impact of Diospyros kaki fruit aqueous extract (DKFAE) on ethanol induced peptic ulcer. The phytochemical studies of DKFAE were investigated using colorometric analysis. Gastric ulcer was induced by one dose of ethanol (5 ml/Kg, b.w) on 24 h empty stomach. Then, the plant extract (200, 400 mg/kg) was orally administrated for 2 weeks. Famotidine (FAM: 40 mg/kg, b.w.): a reference drug was also tested. The effect of mixture dose between the fruit extract and FAM (DKFAE, 50 mg/kg PC, p.o. + FAM, 50 mg/kg PC, p.o.) was also evaluated. One hour after induction of ulcer blood samples were collected, stomach acidity and volume, as well as lesion counts were measured, then stomach and intestine of scarified rats were subjected to biochemical, macroscopic and microscopic studies. Results showed that DKFAE exhibited an important antioxidant potential. In vivo, the results showed that alcohol induced gastric damage, improving oxidative stress markers level such as MDA and H2O2, gastric and intestinal calcium and free iron. The intoxication by ethanol also produce an inflammation occurred by high level of the C-reactive protein (CRP) and alkaline phosphatase (ALP) activity in plasma. In contrast, DKFAE and the mixture dose significantly protect against macroscopic and histological injuries, the secretory profile disturbances, lipid peroxidation, antioxidant enzymes activities and non enzymatic antioxidant level decrease induced by ethanol administration. More impressively, the mixture dose exerted the more excellent effect than DKFAE and famotidine each alone showing is possible synergism. [ABSTRACT FROM AUTHOR]

The Fenton reaction is known for generating highly reactive hydroxyl radicals that are applied to accelerate the polishing removal rate of chemically inert SiC substrates. However, previous research primarily focuses on the polishing removal rate acceleration on the C surfaces of SiC substrates, and very limited studies have been conducted to investigate whether the hydroxyl radicals produced by the Fenton reaction serve as the primary agents of oxidative activity. Furthermore, the oxidation ability of hydroxyl radicals on the C surface and its relationship with their concentration are still not well-established. Therefore, more extensive research is needed to gain comprehensive understanding on the role of hydroxyl radicals in the oxidative activity on the C surface and their concentration-dependent effects. In this study, the polishing results of alumina, cerium oxide, and silica containing polishing slurries with and without Fenton reaction were compared and analyzed. The material removal rate (MRR) of the C surfaces of SiC substrates was significantly improved after the introduction of the Fenton reaction in alumina-containing slurry at pH 4, resulting in a smoother surface. Low-field nuclear magnetism, atomic force microscopy (AFM), ultraviolet spectrophotometry, and X-ray photoelectron spectroscopy (XPS) were employed to gain insights on inter-particle interactions and oxidation mechanisms of C face of SiC in presence of Fenton reaction. The results revealed that while hydroxyl radicals demonstrated potent oxidation ability, they alone were incapable of oxidizing C face of SiC. [ABSTRACT FROM AUTHOR]

The Michael J. Fox Foundation has been funding research on Parkinson's disease for 35 years, but has yet to find a cure. This is due to a problem with the philosophy behind the development of modern medical treatments. In this paper, we will introduce "smart medicine" with a substance that can solve all the problems of central nervous system drugs. The substance is the smallest diatomic molecule, the hydrogen molecule. Due to their size, hydrogen molecules can easily penetrate the cell membrane and enter the brain. In the midbrain of Parkinson's disease patients, hydroxyl radicals generated by the Fenton reaction cause a chain reaction of oxidation of dopamine, but hydrogen entering the midbrain can convert the hydroxyl radicals into water molecules and inhibit the oxidation of dopamine. In this paper, we focus on the etiology of neurological diseases, especially Parkinson's disease, and present a case in which hydrogen inhalation improves the symptoms of Parkinson's disease, such as body bending and hand tremor. And we confidently state that if Michael J. Fox encountered "smart medicine" that could be realized with molecular hydrogen, he would not be a "lucky man" but a "super-lucky man." [ABSTRACT FROM AUTHOR]

The introduction of high‐valence state elements and highly active species is promisingly desired to design superior electrocatalysts for water electrolysis. Exploring scalable synthetic strategies is necessary for an in‐depth understanding of the mechanism of improving electrocatalytic performance. But it remains challenging. Herein, several electrocatalysts through element doping are prepared. The obtained Mo‐CoP3‐2@FeOOH samples show the overpotentials (OER) of 232 mV (alkaline seawater) and 262 mV (KOH electrolyte). As HER catalyst, it also presents an excellent electrocatalytic performance. The above electrocatalysts are utilized as anode/cathode to assemble devices for alkaline seawater/water electrolysis, which delivers a cell voltage of 1.58 V and durability of 350 h. Density functional theory calculations reveal that Mo ion doping and FeOOH significantly enhance the density states of the Fermi level and tune the position of the d‐band center. It expedites the charge transfer and decreases the adsorption energy of intermediates. It demonstrates that transition‐metal phosphides coated with highly active FeOOH offer an effective route to fabricate high‐performance and durable catalysts for seawater/water electrolysis. [ABSTRACT FROM AUTHOR]

In the present work, we pioneered a coordinated self-assembly approach aimed at fabricating carrier-free hybrid nanoparticles to address the inherent challenges of the anaerobic microenvironment and the oxidative resistance induced by reductive glutathione (GSH) in photodynamic therapy (PDT). In these nanoparticles, protoporphyrin IX (PP), HIF-1α inhibitor of N, Nʹ-(2,5-Dichlorosulfonyl) cystamine KC7F2 (KC), and the cofactor Fe3+ present hydrogen bond and coordination interaction. The nanoparticles exhibited efficient cellular uptake by CAL-27 cells, facilitating their accumulation in tumors by enhanced permeability and retention (EPR) effect. Under irradiation at 650 nm, the formation of cytotoxic singlet oxygen (1O2) would be enhanced by the synergy effect on the Fenton reaction of Fe3+ ion and the downregulation of the HIF-1α, leading to the improved PDT efficacy both in vitro and in vivo biological studies. Our work opens a new supramolecular approach to prepare hybrid nanoparticles for effective synergy therapy with PDT against cancer cells. [ABSTRACT FROM AUTHOR]

A sequential dual-locked luminescent copper nanoclusters (CuNCs) probe was designed and synthesized for the specific imaging and selective killing of tumor cells. This nanoprobe was prepared by first forming a Fe3+-coupled tannic acid (TA)-stabilized CuNCs (CuNCs-FeIII), which is in quenching state due to the electron transfer between CuNCs and Fe3+, and then coating a protectable layer of hyaluronic acid (HA) on the surface of CuNCs-FeIII to form the final dual-locked nanoprobe (CuNCs-FeIII@HA). When the nanoprobe of CuNCs-FeIII@HA target enter the tumor cells through CD44-HA receptor, HAase will first digest the HA layer of the nanoprobes, and then, GSH over-expressed in tumor cells will reduce Fe3+ to Fe2+, thus restoring the fluorescence emission of CuNCs and at the same time killing the tumor cells with the hydroxyl free radicals (∙OH) produced by the Fenton reaction between Fe2+ and H2O2. This sequential dual-locked luminescent nanoprobe of CuNCs-FeIII@HA has been successfully used for the specific imaging and selective killing of tumor cells. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a multifaceted neurodegenerative disorder characterized by cognitive decline and neuronal loss, representing a most challenging health issue. We present a computational analysis of transcriptomic data of AD tissues vs. healthy controls, focused on the elucidation of functional roles played by long non-coding RNAs (lncRNAs) throughout the AD progression. We first assembled our own lncRNA transcripts from the raw RNA-Seq data generated from 527 samples of the dorsolateral prefrontal cortex, resulting in the identification of 31,574 novel lncRNA genes. Based on co-expression analyses between mRNAs and lncRNAs, a co-expression network was constructed. Maximal subnetworks with dense connections were identified as functional clusters. Pathway enrichment analyses were conducted over mRNAs and lncRNAs in each cluster, which served as the basis for the inference of functional roles played by lncRNAs involved in each of the key steps in an AD development model that we have previously built based on transcriptomic data of protein-encoding genes. Detailed information is presented about the functional roles of lncRNAs in activities related to stress response, reprogrammed metabolism, cell polarity, and development. Our analyses also revealed that lncRNAs have the discerning power to distinguish between AD samples of each stage and healthy controls. This study represents the first of its kind. [ABSTRACT FROM AUTHOR]

• Composite photo–Fenton catalysts of N–doped TiO 2 and schwertmannite were prepared. • N–TiO 2 /SCH displayed a superior BPA degradation activity of ca. 100% within 60 min. • Hydroxyl radical and singlet oxygen are active species in this photo–Fenton system. Potential health risks related to environmental endocrine disruptors (EEDs) have aroused research hotspots at the forefront of water treatment technologies. Herein, nitrogen–doped titanium dioxide/schwertmannite nanocomposites (N–TiO 2 /SCH) have been successfully developed as heterogeneous catalysts for the degradation of typical EEDs via photo–Fenton processes. Due to the sustainable Fe(III)/Fe(II) conversion induced by photoelectrons, as–prepared N–TiO 2 /SCH nanocomposites exhibit much enhanced efficiency for the degradation of bisphenol A (BPA; ca. 100% within 60 min under visible irradiation) in a wide pH range of 3.0-7.8, which is significantly higher than that of the pristine schwertmannite (ca. 74.5%) or N–TiO 2 (ca. 10.8%). In this photo–Fenton system, the efficient degradation of BPA is mainly attributed to the oxidation by hydroxyl radical (•OH) and singlet oxygen (1O 2). Moreover, the possible catalytic mechanisms and reaction pathway of BPA degradation are systematically investigated based on analytical and photoelectrochemical analyses. This work not only provides a feasible means for the development of novel heterogeneous photo–Fenton catalysts, but also lays a theoretical foundation for the potential application of mineral–based materials in wastewater treatment. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) emerges as an environmentally sustainable oxidant with great potential in diverse fields. However, the efficiency of H2O2 generation via photocatalysis remains suboptimal. Fundamentally, this inefficiency stems from the rapid recombination of photogenerated electron–hole pairs, limited surface or interface activity, restricted solar light absorption, and poor selectivity. Here, we discuss the fundamental mechanisms of photocatalytic H2O2 generation over the key material systems and highlight the most effective design strategies to address the unmet challenges faced by these systems. This review not only discusses fundamental insights into the mechanisms of photocatalytic H2O2 generation but also provides perspectives on future directions for the development of photocatalytic materials with high-efficiency and stability in generating H2O2. [ABSTRACT FROM AUTHOR]

The effectiveness of tumor treatment using reactive oxygen species as the primary therapeutic medium is hindered by limitations of tumor microenvironment (TME), such as intrinsic hypoxia in photodynamic therapy (PDT) and overproduction of reducing glutathione (GSH) in chemodynamic therapy (CDT). Herein, we fabricate metal-polyphenol self-assembled nanodots (Fe@BDP NDs) guided by second near-infrared (NIR-II) fluorescence imaging. The Fe@BDP NDs are designed for synergistic combination of type-I PDT and CDT-amplified ferroptosis. In a mildly acidic TME, Fe@BDP NDs demonstrate great Fenton activity, leading to the generation of highly toxic hydroxyl radicals from overproduced hydrogen peroxide in tumor cells. Furthermore, Fe@BDP NDs show favorable efficacy in type-I PDT, even in tolerating tumor hypoxia, generating active superoxide anion upon exposure to 808 nm laser irradiation. The significant efficiency in reactive oxygen species (ROS) products results in the oxidation of sensitive polyunsaturated fatty acids, accelerating lethal lipid peroxidation (LPO) bioprocess. Additionally, Fe@BDP NDs illustrate an outstanding capability for GSH depletion, causing the inactivation of glutathione peroxidase 4 and further promoting lethal LPO. The synergistic type-I photodynamic and chemodynamic cytotoxicity effectively trigger irreversible ferroptosis by disrupting the intracellular redox homeostasis. Moreover, Fe@BDP NDs demonstrate charming NIR-II fluorescence imaging capability and effectively accumulated at the tumor site, visualizing the distribution of Fe@BDP NDs and the treatment process. The chemo/photo-dynamic-amplified ferroptotic efficacy of Fe@BDP NDs was evidenced both in vitro and in vivo. This study presents a compelling approach to intensify ferroptosis via visualized CDT and PDT. In this study, we detailed the fabrication of metal-polyphenol self-assembled nanodots (Fe@BDP NDs) guided by second near-infrared (NIR-II) fluorescence imaging, aiming to intensify ferroptosis via the synergistic combination of type-I PDT and CDT. In a mildly acidic TME, Fe@BDP NDs exhibited significant Fenton activity, resulting in the generation of highly toxic •OH from overproduced H 2 O 2 in tumor cells. Fe@BDP NDs possessed a remarkable capability for GSH depletion, resulting in the inactivation of glutathione peroxidase 4 (GPX4) and further accelerating lethal LPO. This study presented a compelling approach to intensify ferroptosis via visualized CDT and PDT. [Display omitted] [ABSTRACT FROM AUTHOR]

We present results on the potential protective antioxidant properties of indole-3-butyric acid. Indole-3-butyric acid is an indole derivative defined as an auxin and widely known as a plant growth regulator. It naturally occurs in Arabidopsis thaliana, which is applied as a model plant in genetic studies. Oxidative damage to membrane lipids (lipid peroxidation; LPO) in porcine thyroid homogenates was induced by Fenton reaction substrates (Fe2+ + H2O2). Iron (Fe2+) was used in very high concentrations of 1200, 600, 300, 150, 75, 37.5, 18.75, 9.375, 4.687, and 2.343 µM. Indole-3-butyric acid (10.0, 5.0, 2.5, 1.25, and 0.625 mM) was applied to check whether it prevents the above process. The LPO level, expressed as malondialdehyde + 4-hydroxyalkenals (MDA + 4-HDA) concentration, was measured spectrophotometrically. Expectedly, Fenton reaction substrates, in a Fe2+ concentration-dependent manner, increased LPO level, with the lowest effective concentration of iron being 9.375 µM. In the case of almost all concentrations of indole-3-butyric acid, this auxin has exhibited very promising antioxidant protection, with the most effective concentrations being 10.0 and 5.0 mM; however, as low concentrations of indole-3-butyric acid at 1.25 mM was still effective. Indole-3-butyric acid used alone did not change the basal level of LPO, which is a favourable effect. To summarise, indole-3-butyric acid has protective antioxidant properties against experimentally induced oxidative damage to membrane lipids in the thyroid, and this is for the first time documented in the literature. This compound can be considered a natural protective agent present in plants, which can serve as a dietary nutrient. [ABSTRACT FROM AUTHOR]

Piezocatalytic Fenton (PF) system emerges as a promising approach to wastewater treatment by leveraging piezocatalysis to enhance Fenton‐like reactions. However, conventional piezocatalysts encounter challenges because they often compromise catalytic properties in biased favor of superior piezoelectricity, resulting in sluggish catalytic kinetics. To tackle this trade‐off, here a novel class of kesterite‐type narrow bandgap piezoelectrics, Cu2XSnS4 (CXTS, X = Zn, Ni, Co), is developed for PF reactions, which exhibit a unique combination of physicochemical attributes favorable for catalysis such as narrow bandgap (1.2–1.5 eV), high free charge density (1 × 1018 cm−3), mobility, and redox activity while retaining excellent piezoelectricity (62–142 pm V−1). With the well‐balanced piezoelectric, semiconducting, and catalytic properties, CXTS‐based PF systems demonstrate outstanding performance for tetracycline degradation, delivering a notable reaction kinetics of 0.34 min−1 only with a minor H2O2 dosage (1.2 mm), outperforming most of the conventional Fenton‐like reactions requiring a large amount H2O2 dosage by a factor up to 10. Such a remarkable performance is fulfilled by the simultaneously effective H2O2 activation and in situ generation of reactive oxygen species from oxygen and water via piezocatalysis. Additionally, the distinctive hierarchical morphology consisting of 2D nanosheets enables easy crystal domain deformation to trigger the piezoelectric effect, thereby drastically reducing the mechanical energy input required to drive redox reactions. Rigorous testing has validated the viability and practical feasibility of this system. The study offers a new design strategy for highly efficient piezocatalysts in the PF systems, enabling a cost‐effective and sustainable water treatment approach. [ABSTRACT FROM AUTHOR]

In the tumor treatment by Fenton reaction‒based nanocatalytic medicines, the gradual consumption of Fe(II) ions greatly reduces the production of hydroxyl radicals, one of the most active reactive oxygen species (ROS), leading to much deteriorated therapeutic efficacy. Meanwhile, the ROS consumption caused by the highly expressed reduced glutathione (GSH) in the tumor microenvironment further prevents tumor apoptosis. Therefore, using the highly expressed GSH in tumor tissue to promote the Fe(III) reduction to Fe(II) can not only weaken the resistance of tumor to ROS attack, but also generate enough Fe(II) to accelerate the Fenton reaction. In view of this, an allicin‒modified FeO1‐xOH nanocatalyst possessing varied valence states (II, III) has been designed and synthesized. The coexistence of Fe(II)/Fe(III) enables the simultaneous occurrence of Fenton reaction and GSH oxidation, and the Fe(III) reduction by GSH oxidation results in the promoted cyclic conversion of Fe ions in tumor and positive catalytic therapeutic effects. Moreover, allicin capable of regulating cell cycle and suppressing tumor growth is loaded on FeO1‐xOH nanosheets to activate immune response against tumors and inhibit tumor recurrence, finally achieving the tumor regression efficiently and sustainably. This therapeutic strategy provides an innovative approach to formulate efficient antitumor nanomedicine for enhanced tumor treatment. [ABSTRACT FROM AUTHOR]

Tumor tissues are well known for their unique high hydrogen peroxide (H2O2) microenvironment. How to exploit this tumor microenvironment for tumor cell killing is a question. In this study, a Mn-doped metal-organic framework (Mn-ZIF) was constructed. It possesses good peroxidase (POD) activity, which can oxidize tumor-localized H2O2 into hydroxyl radicals (·OH), that possesses the ability to directly kill tumor cells. More surprisingly, in vivo experiments the researchers not only observed the tumor-killing effect of Mn-ZIF, but also found it changes in macrophage phenotype in the tumor region. There was an increase in macrophage polarization towards the M1 subtype. This suggests that the tumor-killing effect of Mn-ZIF not only comes from its POD activity, but also regulates the immune microenvironment in the tumor region. In conclusion, the preparation of Mn-ZIF provides a new way for comprehensive tumor therapy. [ABSTRACT FROM AUTHOR]

Metal-free photocatalysis that produces reactive oxygen species (ROS) shows significant promising applications for environmental remediation. Herein, we constructed iodine-doped carbon nitride (I-CN) for applications in the photocatalytic inactivation of bacteria and the heterogeneous Fenton reaction. Our findings revealed that I-CN demonstrates superior photocatalytic activity compared to pure CN, due to enhanced light adsorption and a narrowed band gap. Antibacterial tests confirmed that I-CN exhibits exceptional antibacterial activity against both Escherichia coli and Staphylococcus aureus. The results showed that I-CN effectively generates superoxide radicals and hydroxyl radicals under light irradiation, resulting in enhanced antibacterial activity. In addition, I-CN can also be applied for a heterogeneous photo-Fenton-like reaction, achieving a high performance for the degradation of sulfamethoxazole (SMX), a typical antibiotic, via the photocatalytic activation of peroxymonosulfate (PMS). These results shed new light on the fabrication of metal-free nanozymes and their applications for disinfection and water decontamination. [ABSTRACT FROM AUTHOR]