Search Results (5,398)

Background: This study aimed to evaluate the impact of different chemical treatments on titanium implant surfaces and their biological compatibility. Methods: Titanium dental implants were immersed in Ringer’s solution, hydrogen peroxide (3%), citric acid (40%), EDTA (40%), or a citric–phosphoric acid mixture. Electrochemical behavior was analyzed using open-circuit potential monitoring and electrochemical impedance spectroscopy over 168 h. Cytocompatibility was assessed by culturing human gingival mesenchymal stem cells (MSCs) directly on treated implants and in conditioned media, followed by viability evaluation through CCK-8 assays. Results: Citric acid and Ringer’s solution preserved passive film stability and supported high MSC viability (>75%) with minimal cytotoxic effects. Hydrogen peroxide and the citric–phosphoric acid mixture caused pronounced surface corrosion, decreased impedance stability, and significantly reduced cell viability (57–65%). EDTA-treated surfaces showed intermediate results, with moderate viability but impaired cell adhesion. Conclusion: The findings highlight the dual influence of chemical decontamination on implant stability and biological response. Citric acid and Ringer’s solution appear to be safer protocols for surface decontamination, whereas hydrogen peroxide and mixed acid treatments should be applied with caution due to their detrimental electrochemical and cytotoxic effects. Full article

The emergence of Candida auris as a disheartening fungal pathogen in healthcare settings has prompted urgent re-evaluation of containment and mitigation strategies. This review critically examines the biological persistence, environmental adaptability, and resistance to standard antifungal therapies of the pathogen, particularly regions with limited surveillance infrastructure. Based on regional experiences, such as those in Saudi Arabia and the Middle East in general, the study reveals systemic weaknesses in diagnosis, reporting, and environmental sanitation. Special consideration is paid to the combination of new disinfection technologies, including ultraviolet irradiation systems and hydrogen peroxide vaporisation, with institutional behaviour change strategies. This discussion shows the importance of synchronising technological development with frequent employee contributions and cross-functional planning. It also encourages the international standardisation of diagnostic platforms and the launch of real-time genomic surveillance to reveal evolutionary trends. Finally, the findings justify the shift towards proactive models of infection control that are founded on the resilience of systems and the agility of institutions. This paper is a synthesis of epidemiological patterns, decontamination strategies and behavioural knowledge to contribute to an emerging body of knowledge that can help to fortify healthcare settings against current fungal threats. Full article

Nickel oxide (NiO), a wide bandgap p-type semiconductor, has emerged as a promising material for electrochemical sensing owing to its excellent redox properties, chemical stability, and facile synthesis. Its strong electrocatalytic activity enables effective detection of diverse analytes, including glucose, hydrogen peroxide, environmental pollutants, and biomolecules. Advances in nanotechnology have enabled the development of NiO-based nanostructures such as nanoparticles, nanowires, and nanoflakes, which offer enhanced surface area and improved electron transfer. Integration with conductive materials like graphene, carbon nanotubes, and metal–organic frameworks (MOFs) further enhance sensor performance through synergistic effects. Innovations in synthesis techniques, including hydrothermal, sol–gel, and green approaches, have expanded the applicability of NiO in next-generation sensing platforms. This review summarizes recent progress in the structural engineering, composite formation, and electrochemical mechanisms of NiO-based materials for advanced electrochemical sensing applications. Full article

Stem cell (SC)-based therapy exploits the ability of cells to migrate to damaged tissues and repair them. In this context, there is a strong interest in the use of mesenchymal stem cells (MSCs), multipotent SCs that are easy to obtain and are able to differentiate into various cell lineages. However, MSCs undergo cellular senescence during in vitro expansion, and may also become senescent in vivo, influenced by multiple molecular, cellular, and environmental interactions. Therefore, the development of in vitro cell models is crucial to study the mechanisms underlying senescence in MSCs. This study aimed to investigate the effects of tert-butyl hydroperoxide (t-BHP) as a senescence inducer in human dermal MSCs (hDMSCs), a promising tool for tissue repair. t-BHP induced a pro-senescent effect on hDMSCs greater than hydrogen peroxide (H₂O₂), as evidenced by ROS production, DNA damage, cell cycle arrest, inhibition of cell proliferation, changes in cellular and nuclear morphology, and cytoskeletal reorganization, as well as the increase in other senescence markers, including senescence-associated β-galactosidase (SA-β-Gal)-positive cells, and senescence-associated secretory phenotype (SASP). These results indicate that t-BHP could be a promising compound for inducing stress-induced premature senescence (SIPS) in hDMSCs, providing a valuable tool to investigate this process and evaluate the efficacy of senolytic compounds. Full article

Neutrophils are an essential protective component of the innate immune system. However, in severe bacterial infections, neutrophils are known to mis-localise from the primary site of infection to other organs, where excessive release of cytokines, chemokines, and neutrophil extracellular traps (NETs) can induce organ damage and death. In this study, we use an animal model of bacterial infection originating in the peritoneum to show that hydrogen peroxide (H₂O₂, a potent neutrophil chemoattractant) is initially released in high concentrations both in the peritoneum and in multiple ‘off-target’ organs (lungs, liver and kidneys). The initial high H₂O₂ release inhibits neutrophil chemotaxis, but after 24 h concentrations of H₂O₂ reduce and can promote neutrophil migration to organs, where they release pro-inflammatory cytokines and chemokines along with NETs. The antimalarial compound artesunate potently inhibits neutrophil migration to off-target organs. It also abolishes cytokine, chemokine, and NET production, suggesting that artesunate may be a valuable novel therapy for preventing off-target organ inflammation associated with severe bacterial infections. Finally, the potency of H₂O₂ as a chemoattractant is shown by in vitro experiments in which, faced with competing gradients of H₂O₂ and other chemoattractants, neutrophils preferentially migrate towards H₂O₂. Full article

Recently, researchers have been focused on the recycling as well as transforming of bio-waste streams into a valuable resource. Banana peels are promising for such application, due to their wide availability. In this context, the integration of banana peel-derived biochar with environmentally benign magnetite has significantly broadened its potential applications as a solar photocatalyst compared to the conventional photocatalysts. The materials are mixed in varied proportions of Ban-Char500-Mag@-(0:1), Ban-Char500@Mag-(1:1) and Ban-Char500@Mag-(2:1) and characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM) augmented with dispersive X-ray spectroscopy (EDX). Such modification is leading to an improvement in its application as a solar photocatalyst using the photochemical solar collector facility. The study discusses the factors controlling acetaminophen removal from aqueous effluent within 30 min of solar illumination time. Furthermore, the highlighted optimum parameters are pH 3.0, using 10 mg/L of the Ban-Char500@Mag-(1:1) catalyst and 100 mg/L of the hydrogen peroxide as a Fenton combination system for removing a complete acetaminophen from wastewater (100% oxidation). Also, the temperature influence in the oxidation system is studied and the high temperature is unfavorable, which verifies that the reaction is exothermic in nature. The catalyst is signified as a sustainable (recoverable, recyclable and reusable) substance, and showed a 72% removal even though it was in the six cyclic uses. Further, the kinetic study is assessed, and the experimental results revealed the oxidation process is following the first-order kinetic reaction. Also, the kinetic–thermodynamic parameters of activation are investigated and it is confirmed that the oxidation is exothermic and non-spontaneous in nature. Full article

Osteoarthritis (OA) is primarily a degenerative disease triggered by joint inflammation and oxidative stress. While Aster glehni is an edible and traditionally medicinal herb, the beneficial effect of A. glehni on OA progression remains unknown. This study aimed to investigate the effect of A. glehni extract (AGE) and its primary biological compound—3,5-dicaffeoylquinic acid (3,5-DCQA)—on inflammation and oxidative stress in chondrocytes. AGE effectively inhibited the expression of interleukin (IL)-6, cyclooxygenase (COX)-2, matrix metalloproteinase (MMP)-1, and MMP-13 in chondrocytes stimulated by IL-1β for 24 h. In contrast, 3,5-DCQA did not inhibit IL-6, COX-2, and MMP expressions under the same conditions. However, when chondrocytes were stimulated by IL-1β for a short duration (6 h), 3,5-DCQA suppressed IL-6, COX-2, and MMP expressions. The inhibition of IL-6, COX-2, and MMP expressions by AGE was associated with the p38 kinase and nuclear factor-κB signaling pathways, but not ERK and JNK signaling pathways. Furthermore, AGE prevented cell apoptosis and reduced intracellular reactive oxygen species levels in chondrocytes induced by hydrogen peroxide (H₂O₂). AGE restored the decreased superoxide dismutase 1 and catalase mRNA expressions caused by H₂O₂. Collectively, AGE may protect against cartilage deterioration by inhibiting inflammation and oxidative stress, making it a promising therapeutic agent for alleviating OA. Full article

Pre-harvest sprouting (PHS) reduces the quality and quantity of crop seeds. PHS can be imposed through the embryo or husk pathway of cereal crops. Most reported PHS seeds are imposed via the embryo pathway. Here, we generated transgenic rice plants overexpressing rice melatonin 2-hydroxylase (OsM2H), which catalyzes the hydroxylation of melatonin to 2-hydroxymelatonin (2-OHM). OsM2H overexpression (M2H-OE) showed PHS under paddy conditions. Germination assays revealed that intact seeds harvested at 26 and 36 days after heading (DAH) showed PHS, whereas dehusked seeds did not, indicating husk-imposed PHS. Overproduction of 2-OHM was observed in M2H-OE seeds compared to wild-type control. In addition, M2H-OE lines produced more hydrogen peroxide than the wild-type. 2-OHM-induced reactive oxygen species resulted in the induction of OsGA3ox2, a gibberellin (GA) biosynthesis gene, and repression of OsGA2ox3, a GA degradation gene, in caryopses at 2 DAH, but in the induction of the ABA degradation gene OsABA8ox3 in intact seeds at 26 DAH. In addition, M2H-OE seedlings were longer and showed increased levels of hydrogen peroxide and OsGA3ox2 expression versus the wild-type. This is the first report showing that 2-OHM can induce PHS via the husk pathway in rice seeds through the induction of GA biosynthetic and ABA degradation genes. Full article

Halophytes such as Salicornia europaea rely on biochemical and structural mechanisms to survive in saline environments. This study aimed to evaluate oxidative stress and structural defense responses in four inland populations—Poland (Inowrocław, Ciechocinek), Germany (Salzgraben-Salzdahlum, Salz), and Soltauquelle (Soltq)—subjected to 0, 200, 400, and 1000 mM NaCl, using non-destructive, image-based approaches. Lipid peroxidation was assessed via malondialdehyde (MDA) detected with Schiff’s reagent, and hydrogen peroxide (H₂O₂) accumulation was visualized with 3,3′-diaminobenzidine (DAB). Roots and shoots were analyzed through colour image analysis and quantified using a computer vision system (CVS). MDA accumulation revealed population-specific differences, with Salz tending to exhibit lower peroxidation, characterized by lower L* ≈ 42–43 and higher b* ≈ 37–18 in shoots at 200–400 mM, which may reflect a potentially more effective salt-management strategy. Although H₂O₂ responses deviated from a direct salinity-dependent trend, particularly in the tolerant Salz and Soltq populations, both approaches effectively tracked population-specific adaptation, with German populations displaying detectable basal H₂O₂ levels, consistent with its multifunctional signalling role in salt management and growth regulation. Structural defences were further explored through histochemical mapping and image analysis of pectin and lignin distribution, which revealed population-specific patterns consistent with cell wall remodelling under stress. Non-destructive, image-based methods proved effective for detecting oxidative and structural responses in halophytes. Such a non-destructive, cost-efficient, and reproducible approach can accelerate the identification of salt-tolerant ecotypes for saline agriculture and reinforce S. europaea as a model species for elucidating salt-tolerance mechanisms. Full article

The development of cost-effective and highly sensitive hydrogen peroxide (H₂O₂) biosensors with robust stability is critical due to the pivotal role of H₂O₂ in biological processes and its broad utility across various applications. In this work, porous ceria hollow microspheres (CeO₂-phm) were synthesized using a solvothermal synthesis method and employed in the construction of an electrochemical biosensor for H₂O₂ detection. The resulting CeO₂-phm featured a uniform pore size centered at 3.4 nm and a high specific surface area of 168.6 m²/g. These structural attributes contribute to an increased number of active catalytic sites and promote efficient electrolyte penetration and charge transport, thereby enhancing its electrochemical sensing performance. When integrated into screen-printed carbon electrodes (CeO₂-phm/cMWCNTs/SPCE), the CeO₂-phm/cMWCNTs/SPCE-based biosensor exhibited a wide linear detection range from 0.5 to 450 μM, a low detection limit of 0.017 μM, and a high sensitivity of 2070.9 and 2161.6 μA·mM⁻¹·cm⁻²—surpassing the performance of many previously reported H₂O₂ sensors. In addition, the CeO₂-phm/cMWCNTs/SPCE-based biosensor possesses excellent anti-interference performance, repeatability, reproducibility, and stability. Its effectiveness was further validated through successful application in real sample analysis. Hence, CeO₂-phm with solvothermal synthesis has great potential applications as a sensing material for the quantitative determination of H₂O₂. Full article

The spatiotemporal regulatory mechanism underlying silicon (Si)-mediated cadmium (Cd) detoxification in rice (Oryza sativa L.) was investigated using non-invasive micro-test technology (NMT), combined with physiological and biochemical analyses. The results revealed the following: (1) Si significantly inhibited Cd²⁺ influx into rice roots, with the most pronounced reductions in ion flux observed under moderate Cd stress (Cd50, 50 μmol·L⁻¹), reaching 35.57% at 7 days and 42.30% at 14 days. Cd accumulation in roots decreased by 34.03%, more substantially than the 28.27% reduction observed in leaves. (2) Si application enhanced photosynthetic performance, as evidenced by a 14.21% increase in net photosynthetic rate (Pn), a 32.14% increase in stomatal conductance (Gs), and a marked restoration of Rubisco activity. (3) Si mitigated oxidative damage, with malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) levels reduced by 11.29–21.88%, through the upregulation of antioxidant enzyme activities (SOD, APX, CAT increased by 15.34–38.33%) and glutathione metabolism (GST activity and GSH content increased by 60.78% and 51.35%, respectively). (4) The mitigation effects of Si were found to be spatiotemporally specific, with stronger responses under Cd50 than Cd100 (100 μmol·L⁻¹), at 7 days (d) compared to 14 d, and in roots relative to leaves. Our study reveals a coordinated mechanism by which Si modulates Cd uptake, enhances photosynthetic capacity, and strengthens antioxidant defenses to alleviate Cd toxicity in rice. These findings provide a scientific basis for the application of Si in mitigating heavy metal stress in agricultural systems. Full article

Pineapple leaf fibers (PALFs), obtained from abundant yet underutilized pineapple leaf residues, represent a promising feedstock for producing fibrillated cellulose. In this work, cellulosic fibers were isolated and characterized by Fiber Quality Analysis (FQA), showing lengths between 0.33 and 0.47 mm and widths of 12.2 µm after organosolv pulping using ethanol and acetic acid as a catalyst, followed by hydrogen peroxide bleaching with diethylenetriaminepentaacetic acid as a chelating agent. The cellulosic fibers were then subjected to TEMPO-mediated oxidation and subsequently disintegrated by microfluidization to produce micro-/nanofibrillated cellulose (MNFC) with a carboxylate content of 0.85 and 1.00 mmol COO⁻/g, zeta potential of −41 and −53 mV, and average widths of 15 and 12 nm for unbleached and bleached nanofibrils, respectively. The nanofibrillation yields were 73% and 68% for the bleached and unbleached MNFC samples, indicating the presence of some non-fibrillated or partially fibrillated fractions. X-ray diffraction analysis confirmed preservation of cellulose type I crystalline structure, with increased crystallinity, reaching 85% in the bleached MNFC. These findings demonstrate the feasibility of a sequential process, combining organosolv pulping, hydrogen peroxide bleaching, TEMPO-mediated oxidation, and microfluidization, for preparing MNFC from pineapple leaf fibers. Overall, this study highlights pineapple leaf residues as a sustainable source of MNFC, supporting strategies to transform agricultural waste into valuable bio-based materials. Full article

This study investigated the phylogenetic relationships in the pear calcium-dependent protein kinase (CDPK) pan-gene family and elucidated its role in the resistance to scab disease caused by Venturia nashicola. By integrating data from eight genomic sets from five cultivated pear species, Pyrus bretschneideri, P. ussuriensis, P. sinkiangensis, P pyrifolia, and P. communis, along with P. betulifolia and interspecific hybrids, 63 PyCDPK family members were identified. Among these, P. communis possessed the highest number of CDPK genes, whereas P. bretschneiderilia had the fewest. These genes encode proteins ranging from 459 to 810 amino acids in length, and are predominantly localized to the cell membrane. Six genes, PyCDPK9, PyCDPK11, PyCDPK12, PyCDPK14, PyCDPK16, and PyCDPK19, were classified as core members of the pan-genome, and PyCDPK19 showed evidence of positive selection pressure. Clustering analysis and transcriptomic expression profiling of disease-resistance-related CDPKs identified PyCDPK19 as a key candidate associated with scab resistance. Promoter analysis revealed that the regulatory region of PyCDPK19 contains multiple cis-acting elements involved in defense responses and methyl jasmonate signaling. Transient overexpression of PyCDPK19 in tobacco leaves induced hypersensitive cell necrosis, accompanied by significant increases in hydrogen peroxide (H₂O₂) accumulation and malondialdehyde (MDA) content. Similarly, overexpression in pear fruit callus tissue followed by pathogen inoculation resulted in elevated levels of both H₂O₂ and MDA. Collectively, these findings indicate that PyCDPK19 mediates defense responses through the activation of the reactive oxygen species pathway in both tobacco and pear plants, providing a promising genetic target for enhancing scab resistance in pears. Full article

In this study, the use of spent coffee waste as a green precursor of polyphenolic compounds, which are subsequently employed as reducing agents for the synthesis of zero-valent iron nanoparticles (nZVI) aimed at the efficient removal of dyes from aqueous systems, has been investigated. The nanoparticles, generated in situ in the presence of controlled amounts of hydrogen peroxide, were applied in the removal of organic dyes—including methylene blue, methyl orange, and orange G—through a heterogeneous Fenton-like catalytic process. The synthesized nZVI were thoroughly characterized by nitrogen adsorption at 77 K, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), and powder X-ray diffraction (XRD). A statistical design of experiments and response surface methodology were employed to evaluate the effect of polyphenol, Fe(III), and H₂O₂ concentrations on dye removal efficiency. Results showed that under optimized conditions, a 100% removal efficiency could be achieved. This work highlights the potential of nZVI synthesized from agro-industrial waste through sustainable routes as an effective solution for water remediation, contributing to circular economy strategies and environmental protection. Full article

Animal venoms are rich in bioactive molecules with promising biotechnological potential. They comprise both protein and non-protein toxins. Among the protein toxins are enzymes, such as phospholipases A₂, proteases and L-amino acid oxidases (LAAOs). LAAOs exhibit antimicrobial, antiparasitic, antiviral, and anticancer effects, making them potential candidates for biotechnological applications. These activities are linked to their ability to catalyze oxidative reactions that convert L-amino acids into α-keto acids, releasing ammonia and hydrogen peroxide, which contribute to the immune response, pathogen elimination, and oxidative stress. However, in snakes of the Micrurus genus, LAAOs generally represent a small portion of the venom (up to ~7%), which limits their isolation and study. To overcome this, the present study aimed to produce Ml-LAAO, the enzyme from Micrurus lemniscatus, through heterologous expression in mammalian cells. The gene sequence was inferred from its primary structure and synthesized into the pSecTag2B vector for expression in HEK293T cells. After purification using a His Trap-HP column, the presence of recombinant Ml-LAAO (Ml-LAAOrec) was confirmed by Western blot and mass spectrometry, validating its identity. These results support successful recombinant expression of Ml-LAAO and highlight its potential for scalable production and future biotechnological applications. Full article