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For environmental applications, it is crucial to rationally design and synthesize photocatalysts with positive exciton splitting and interfacial charge transfer. Here, a novel Ag-bridged dual Z-scheme Ag/g-C3N4/CoNi-LDH plasmonic heterojunction was successfully synthesized using a simple method, with the goal of overcoming the common drawbacks of traditional photocatalysts such as weak photoresponsivity, rapid combination of photo-generated carriers, and unstable structure. These materials were characterized by XRD, FT-IR, SEM, TEM UV-Vis/DRS, and XPS to verify the structure and stability of the heterostructure. The pristine LDH, g-C3N4, and Ag/g-C3N4/CoNi-LDH composite were investigated as photocatalysts for water remediation, an environmentally motivated process. Specifically, the photocatalytic degradation of tetracycline was studied as a model reaction. The performance of the supports and composite catalyst were determined by evaluating both the degradation and adsorption phenomenon. The influence of several experimental parameters such as catalyst loading, pH, and tetracycline concentration were evaluated. The current study provides important data for water treatment and similar environmental protection applications.
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Nanocomposites , Photolyse , Argent , Polluants chimiques de l'eau , Purification de l'eau , Nanocomposites/composition chimique , Polluants chimiques de l'eau/composition chimique , Purification de l'eau/méthodes , Argent/composition chimique , Catalyse , Nitriles/composition chimique , Composés de l'azote/composition chimique , Adsorption , GraphiteRÉSUMÉ
The unprecedented use of high-resolution continuum source molecular absorption spectrometry (HR-CS MAS) for the fractionation of organic and inorganic sulfur (S) species through monitoring the CS molecule is presented here. Two separate methods for determining organic (CSorg) and inorganic (CSino) sulfur were developed to work sequentially. The optimized temperature program for both methodologies has two pyrolysis steps and one vaporization step (1st Tpyr: 1800 and 2ndTpyr: 800 °C, and Tvap: 2500 °C). The fractionation was achieved by implementing hydrophobic Pd NPs and Ca as chemical modifiers for the CSorg and CSino methods. Method development was performed by applying different statistical models, allowing the definition of optimal conditions for the chemical modifier mass, and minimizing the S species interconversion, i.e., Doehlert design, and central composite design. The limits of detection (LoD) for CSorg and CSino were 2.4 and 2.1 mg L-1, respectively. Recovery tests evaluated the method's specificity and accuracy; over 92 % recovery was found for both CSorg and CSino. Thus, the proposed methods offer a reliable alternative for fractionating organic and inorganic S by using HR-CS MAS.
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Bismuth lipophilic nanoparticles (BisBAL NPs) and cetylpyridinium chloride (CPC) are antineoplastic and antimicrobial in vitro. As a next pre-clinical step, a clinically viable dosage form for vaginal application was developed. Compendial pharmacopeial tests (mass uniformity, disintegration, and compressive mechanics) and inductively coupled plasma optical emission spectroscopy were conducted on in-house developed glycerinated gelatin (60:15 v/w) vaginal ovules containing BisBAL NP-CPC. The antimycotic activity of BisBAL NP-CPC vaginal ovules was analyzed using disk diffusion and cell viability XTT assays. The antitumor properties of BisBAL NP-CPC vaginal ovules were assessed by cell viability MTT tests. BisBAL NP-CPC and drug-free vaginal ovules deposited into ex vivo porcine vaginas disaggregated without signs of adverse cytotoxicity within the timespan of clinical efficacy. BisBAL NP-CPC vaginal ovules demonstrated antifungal efficacy comparable to miconazole: C. albicans growth inhibition haloes in diffusion tests were 23 ± 0.968 mm (n = 3) for BisBAL NP-CPC and 20.35 ± 0.899 mm (n = 3) for miconazole. Likewise, BisBAL NP-CPC vaginal ovules reduced HeLa cell growth by 81%, outperforming the clinical reference of 500 µM 5-fluouracil, which induced a 70% growth inhibition. BisBAL NP-CPC incorporated into glycerinated gelatin vaginal ovules constitute an innovative drug delivery system for topical antimycotic and anti-cervical carcinoma treatments.
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High salinity reduces agriculture production and quality, negatively affecting the global economy. Zinc oxide nanoparticles (ZnO-NPs) enhance plant metabolism and abiotic stress tolerance. This study investigated the effects of 2 g/L foliar Zinc oxide NPs on Zea mays L. plants to ameliorate 150 mM NaCl-induced salt stress. After precipitation, ZnO-NPs were examined by UV-visible spectroscopy, transmission electron microscopy, scanning transmission electron microscopy, energy dispersive X-ray, and particle size distribution. This study examined plant height, stem diameter (width), area of leaves, chlorophyll levels, hydrolyzable sugars, free amino acids, protein, proline, hydrogen peroxide, and malondialdehyde. Gas chromatographic analysis quantified long-chain fatty acids, and following harvest, leaves, stalks, cobs, seeds, and seeds per row were weighed. The leaves' acid and neutral detergent fibers were measured along with the seeds' starch, fat, and protein. Plant growth and chlorophyll concentration decreased under salt stress. All treatments showed significant changes in maize plant growth and development after applying zinc oxide NPs. ZnO-NPs increased chlorophyll and lowered stress. ZnO-NPs enhanced the ability of maize plants to withstand the adverse conditions of saline soils or low-quality irrigation water. This field study investigated the effect of zinc oxide nanoparticles on maize plant leaves when saline water is utilized for growth season water. This study also examined how this foliar treatment affected plant biochemistry, morphology, fatty acid synthesis, and crop production when NaCl is present and when it is not.
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Titanium dioxide nanoparticles (TiO2 NPs) can cause mitochondrial apoptosis of TM4 cells associated with reactive oxygen species (ROS) accumulation and Ca2+ overload, but the relations among these processes remain unclear. This study aimed to evaluate whether the accumulation of ROS caused by TiO2 NPs inhibits MCUb expression, leading to mitochondrial calcium overload and subsequent cell apoptosis through the mitochondrial pathway. TM4 cells were exposed to different concentrations of TiO2 NPs (0, 25, 50, 75, 100 µg/mL) for 24 h. We assessed cell viability, ROS level, MCUb and VDAC1 expression, mitochondrial and cytoplasmic Ca2+ levels, mitochondrial membrane potential (MMP), apoptosis rate, and key proteins related to mitochondrial apoptosis (Bcl-2, Bax, Caspase 3, Caspase 9, p53 and Cyt c). Additionally, the effect of N-acetylcysteine (NAC) on MCUb expression, calcium homeostasis, and cell apoptosis was evaluated. Compared to control group, TiO2 NPs significantly increased ROS level, downregulated MCUb expression, elevated Ca2+ levels in mitochondria and cytoplasm, and enhanced mitochondria-regulated apoptosis, starting from the 50 µg/mL TiO2 NPs group. However, NAC significantly increased MCUb expression, attenuated Ca2+ levels in mitochondria and cytoplasm, and reduced mitochondria-related apoptosis. In conclusion, TiO2 NPs induced ROS accumulation, which inhibited the expression of MCUb. The decreased MCUb level led to Ca2+ overload in mitochondria, causing TM4 cell apoptosis via the mitochondrial pathway. This research elucidates, for the first time, the role of MCUb and its relation with ROS in apoptosis of TM4 cells induced by TiO2 NPs, which supplementing the molecular mechanism of cell apoptosis caused by TiO2 NPs.
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Background: Copper oxide (Cu2O) nanoparticles (CO NPs) are in extensive use during our everyday life as antimicrobial agent, lubricant, in manufacturing electrodes of lithium ion batteries as well as for photo catalytic degradation of organic pollutants. Due to extensive and diverse use Cu2O NPs, they are likely to accumulate in the environment and to affect the live forms. Present investigation was aimed to report the biocompatibility of CO NPs in Wistar rats in sex specific manner. CO NPs, having average diameter of 14.06 nm, were synthesized by co-precipitation method and scanning electron microscopy and X ray diffraction were used for their characterization. Methods: For 14 consecutive days, Wistar rats (6 weeks old) of both sexes were intraperitoneally injected with 10 mg/mL saline/Kg body weight of CO NPs, while the control groups intraperitoneally received saline solution for same duration. Behavioral tests (open field and novel object recognition), complete blood count, selected biomarkers of oxidative stress and Copper concentration in brain and liver were determined in all subjects. Results: High mortality rates [male 40% and female 60%] were observed in rats exposed to CO NPs. A sever decrease in body weight was also observed in both male and female rats exposed to CO NPs. Female rats treated with CO NPs spent significantly more time with novel object as compared to control [P = 0.05] during second trial of novel object test. CO NPs treated female rats had higher mean corpuscular hemoglobin [P < 0.001] levels and Copper concentration in liver [P = 0.04] than control. Male rats exposed to CO NPs had significantly higher mean corpuscular volume [P = 0.02] and superoxide dismutase [SOD] [P = 0.04] in lungs than their control group. All other studied parameters non significantly varied upon comparison between CO NPs treated and untreated rats of both sex. Conclusion: In conclusion, we are reporting that intraperitoneal injections of CO NPs for 14 days can disturb complete blood count and biomarkers of oxidative stress in lungs of Wistar rats.
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OBJECTIVE: To investigate the feasibility of standardizing RT simulation CT scanner protocols between vendors using target-based image quality (IQ) metrics. METHOD AND MATERIALS: A systematic assessment process in phantom was developed to standardize clinical scan protocols for scanners from different vendors following these steps: (a) images were acquired by varying CTDIvol and using an iterative reconstruction (IR) method (IR: iDose and model-based iterative reconstruction [IMR] of CTp-Philips Big Bore scanner, SAFIRE of CTs-Siemens biograph PETCT scanner), (b) CT exams were classified into body and brain protocols, (c) the rescaled noise power spectrum (NPS) was calculated, (d) quantified the IQ change due to varied CTDIvol and IR, and (e) matched the IR strength level. IQ metrics included noise and texture from NPS, contrast, and contrast-to-noise ratio (CNR), low contrast detectability (d'). Area under curve (AUC) of the receiver operation characteristic curve of d' was calculated and compared. RESULTS: The level of change in the IQ ratio was significant (>0.6) when using IMR. The IQ ratio change was relatively low to moderate when using either iDose in CTp (0.1-0.5) or SAFIRE in CTs (0.1-0.6). SAFIRE-2 in CTs showed a closer match to the reference body protocol when compared to iDose-3 in CTp. In the brain protocol, iDose-3 in CTp could be matched to the low to moderate level of SAFIRE in CTs. The AUC of d' was highest when using IMR in CTp with lower CTDIvol, and SAFIRE in CTs performed better than iDose in CTp CONCLUSION: It is possible to use target-based IQ metrics to evaluate the performance of the system and operations across various scanners in a phantom. This can serve as an initial reference to convert clinical scanned protocols from one CT simulation scanner to another.
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Hyperglycemia provides a favorable breeding ground for bacteria, resulting in repeated and persistent inflammation of wounds and prolonged healing processes. In this study, platinum (Pt) nanoparticles (NPs) and glucose oxidase (GOx) were decorated on the surface of camelina lipid droplets (OB) linked with hFGF2, forming PGOB through in situ reduction of Pt ions and electrostatic adsorption, respectively. PGOB exhibits cascade enzyme catalytic activity, which can be activated by glucose in diabetic wound tissues. Specifically, GOx on PGOB catalyzes glucose into hydrogen peroxide, which can further decompose into hydroxyl radicals that have higher toxicity for bacterial inactivation. Additionally, glucose decomposition creates a low pH microenvironment, facilitating the cascade catalytic activity that ensures better bacterial suppression within the wound tissues. Furthermore, hFGF2 promotes the proliferation and migration of fibroblasts. Both in vitro and in vivo experiments confirm that PGOB effectively accelerates wound healing processes through bacteria inactivation and tissue regeneration. This study has developed an alternative strategy for glucose-triggered synergistic cascade therapy for diabetic wounds.
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Dual-mode readout platforms with colorimetric and electrochemiluminescence (ECL) signal enhancement are proposed for the ultrasensitive and flexible detection of the monkeypox virus (MPXV) in different scenes. A new nanotag, Ru@U6-Ru/Pt NPs is constructed for dual-mode platforms by integrating double-layered ECL luminophores and the nanozyme using Zr-MOF (UiO-66-NH2) as the carrier, which not only generates enhanced ECL and colorimetric signals but also provide greater stability than that of commonly used nanotags. Dual-mode platforms are used within 15 min from the "sample in" to the "result out" steps, without nucleic acid amplification. The colorimetric mode allows the screening of MPXV with the visual limit of detection (vLOD) of 0.1 pM (6 × 108 copies µL-1) and the ECL mode supports quantitative detection of MPXV with an LOD as low as 10 aM (6 copies·µL-1), resulting in a broad sensing range of 60 to 3 × 1011 copies·µL-1 (10 orders of magnitude). Validation is conducted using 50 clinical samples, which is 100% concordant to those of quantitative polymerase chain reaction (qPCR), indicating that Ru@U6-Ru/Pt NPs-based dual-mode sensing platforms showed great promise as rapid, sensitive, and accurate tools for diagnosis of the nucleic acid of MPXV and other infectious pathogens.
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MoO3-x NPs was rapidly synthesized at room temperature by an easy stirring method. It was interesting to find that MoO3-x NPs induce OH- to generate active free radicals (ROS), which is a highly promising property in chemiluminescence (CL). Benefiting from the abundant oxygen vacancy, MoO3-x NPs adsorbs H2O2 and turn it into ·OH. The oxidase activity of fluorescein under visible light had already been reported, which catalyzes dissolved oxygen to become O2-· and continue to convert to H2O2. By creating the synergy effect with fluorescein, MoO3-x NPs strengthen the CL intensity of K3[Fe(CN)6]-fluorescein system significantly. Utilizing the quench effect of uric acid for the CL intensity, we developed a rapid, simple, and highly sensitive CL platform for uric acid detection. The linear range was 5-80 µM and the detection limit (LOD) for uric acid was 3.11 µM (S/N = 3). This work expanded the application of MoO3-x NPs in the CL field and developed a simple and highly sensitive CL sensing system to detect UA in human saliva.
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Fluorescéine , Limite de détection , Molybdène , Oxydes , Salive , Acide urique , Acide urique/analyse , Acide urique/composition chimique , Salive/composition chimique , Humains , Fluorescéine/composition chimique , Oxydes/composition chimique , Molybdène/composition chimique , Mesures de luminescence/méthodes , Peroxyde d'hydrogène/composition chimiqueRÉSUMÉ
Clubroot, a devastating soil borne disease affecting 30%â¼50% of Brassicaceae crops worldwide, lacks effective control measures. In the present study, we explored the potential of melatonin (MT) and copper oxide nanoparticle (CuO-NPs) in mitigating clubroot severity in the Brassica rapa ssp. pekinensis. Following 18 h priming with MT, CuO-NPs, or both seeds were grown in controlled environment using synthetic potting mix. Inoculated with Plasmodiophora brassicae spores on 5th day, followed by a soil drench phyto-nano treatment with a week interval. Plants were assessed for various health and growth indices including disease, biometrics, photosynthesis, reactive oxygen species (ROS), antioxidant enzyme activity, hormones and genes expression at onset of secondary clubroot infection using established protocols. Statistical analysis employed ANOVA with Fisher's LSD for significance assessment (P < 0.05). Our results revealed that seed priming with both MT (50 µMol/L) and CuO-NPs (200 mg/L), followed by soil drenching significantly reduced clubroot incidence (38%) and disease index (57%), compared to control treatments. This synergistic effect was associated with enhanced plant growth (shoots: 48% and roots: 59%). Plants treated with both MT and CuO-NPs showed robust antioxidant defenses, significantly increased superoxide dismutase (SOD (25/29%)), catalase (CAT (83/55%)), and ascorbate peroxidase (APX (83/46%)) activity in both shoots/roots, respectively, compared to infected control. Notably, salicylic acid and jasmonic acid levels doubled in treated plants, while stress hormone abscisic acid (ABA) decreased by 80% in roots and 21% in shoots. Gene expression analysis corroborated these findings, showing that the combined treatment activated antioxidant defense genes (SOD, APX and CAT) by 1.9-7.2-fold and upregulated hormone signaling genes JAZ1 (7.8-fold), MYC2 (3.9-fold) and SABP2 (36-fold). Conversely, ABA biosynthesis genes (ABA1 and NCED1) were downregulated up to 7.2-fold, while plant resistance genes NPR1, PRB1 and PDF1.2 were dramatically increased by up to 6.3-fold compared to infected plants. Overall, our combined treatment approach significantly reduces clubroot severity in B. rapa via enhanced antioxidant defenses, improved ROS scavenging, coordinated hormonal regulation and increased pathogen response genes. This study offers promising strategy for developing effective control measures against clubroot in susceptible cruciferous crops.
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Aluminum oxide nanoparticles (Al2O3 NPs) are among the most extensively utilized nanoparticles in nanotechnology and that have negative impacts on the environment. Therefore, the intention of this work is to investigate the protective and therapeutic effects of curcumin in nanoform (Cur NPs) against Al2O3 NPs induced kidney toxicity, oxidative stress, DNA damage, and changes in necrosis factor alpha (TNFα) and proliferating cell nuclear antigen (PCNA) expressions in male rats. Fifty healthy adult male were divided into five groups [G1, control; G2, received 50 mg/kg/day for 4 weeks of Cur NPs orally; G3, received 6 mg/kg BW orally for 4 weeks of Al2O3 NPs; G4, (Cur NPs + Al2O3 NPs) received Cur NPs and Al2O3 NPs at a dose similar to G2 and G3, respectively for 4 weeks; G5, (Al2O3 NPs + Cur NPs) received Al2O3 NPs at a dose similar to G3 for 4 weeks then received Cur NPs at a dose similar to G2 for another 4 weeks]. Current results revealed that Al2O3 NPs induced a significant elevation in serum urea, creatinine, chloride, calcium, kidney malondialdehyde (MDA), DNA damage, injury, TNFα and PCNA expressions and a significant depletion in serum potassium, kidney superoxide dismutase (SOD), glutathione (GSH) as compared to control. On the other hand, treatments of Al2O3 NPs with Cur NPs induced modulation in all altered parameters and improved kidney functions and structure, with best results for the Al2O3 NPs + Cur NPs than Cur NPs + Al2O3 NPs. In conclusion, Cur NPs has the capacity to mitigate the renal toxicity induced by Al2O3 NPs in male albino rats.
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Diabetes mellitus (DM) is a rapidly prevailing disease throughout the world that poses boundless risk factors linked to several health problems. Vildagliptin is the standard dipeptidyl peptidase-4 (DPP-4) inhibitor type of medication that is used for the treatment of diabetes anti-hyperglycemic agent (anti-diabetic drug). The current study aimed to synthesize vildagliptin-loaded ZnO NPs for enhanced efficacy in terms of increased retention time minimizing side effects and increased hypoglycemic effects. Herein, Zinc Oxide (ZnO) nanoparticles (NPs) were constructed by precipitation method then the drug vildagliptin was loaded and drug loading efficiency was estimated by the HPLC method. X-ray diffraction analysis (XRD), UV-vis spectroscopy, FT-IR, scanning electron microscope (SEM), and EDX analysis were performed for the characterization of synthesized vildagliptin-loaded ZnO NPs. The UV-visible spectrum shows a distinct peak at 363 nm which confirms the creation of ZnO NPs and SEM showed mono-dispersed sphere-shaped NPs. EDX analysis shows the presence of desired elements along with the elemental composition. The physio-sorption studies, which used adsorption isotherms to assess adsorption capabilities, found that the Freundlich isotherm model explains the data very well and fits best. The maximum adsorption efficiency of 58.83% was obtained. Further, In vitro, anti-diabetic activity was evaluated by determining the α-amylase and DPP IV inhibition activity of the product formed. The formulation gave maximum inhibition of 82.06% and 94.73% of α-amylase and DPP IV respectively. While at 1000 µg/ml concentration with IC50 values of 24.11 µg/per ml and 42.94 µg/ml. The inhibition of α-amylase can be ascribed to the interactive effect of ZnO NPs and vildagliptin.
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Hypoglycémiants , Nanoparticules , Vildagliptine , Oxyde de zinc , Vildagliptine/composition chimique , Vildagliptine/pharmacologie , Oxyde de zinc/composition chimique , Hypoglycémiants/composition chimique , Hypoglycémiants/pharmacologie , Nanoparticules/composition chimique , Inhibiteurs de la dipeptidyl-peptidase IV/composition chimique , Inhibiteurs de la dipeptidyl-peptidase IV/pharmacologie , Diffraction des rayons X , Vecteurs de médicaments/composition chimique , Spectroscopie infrarouge à transformée de Fourier , Nitriles/composition chimique , HumainsRÉSUMÉ
BACKGROUND: Titanium dioxide nanoparticles (TiO2NPs) are widely used in medical application. However, the relevant health risk has not been completely assessed, the potential of inducing arterial thrombosis (AT) in particular. METHODS: Alterations in platelet function and susceptibility to arterial thrombosis induced by TiO2NPs were examined using peripheral blood samples from healthy adult males and an in vivo mouse model, respectively. RESULTS: Here, using human platelets (hPLTs) freshly isolated from health volunteers, we demonstrated TiO2NP treatment triggered the procoagulant activity of hPLTs through phosphatidylserine exposure and microvesicles generation. In addition, TiO2NP treatment increased the levels of glycoprotein IIb/IIIa and P-selectin leading to aggregation and activation of hPLTs, which were exacerbated by providing physiology-mimicking conditions, including introduction of thrombin, collagen, and high shear stress. Interestingly, intracellular calcium levels in hPLTs were increased upon TiO2NP treatment, which were crucial in TiO2NP-induced hPLT procoagulant activity, activation and aggregation. Moreover, using mice in vivo models, we further confirmed that TiO2NP treatment a reduction in mouse platelet (mPLT) counts, disrupted blood flow, and exacerbated carotid arterial thrombosis with enhanced deposition of mPLT. CONCLUSIONS: Together, our study provides evidence for an ignored health risk caused by TiO2NPs, specifically TiO2NP treatment augments procoagulant activity, activation and aggregation of PLTs via calcium-dependent mechanism and thus increases the risk of AT.
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Plaquettes , Activation plaquettaire , Agrégation plaquettaire , Thrombose , Titane , Titane/toxicité , Animaux , Humains , Agrégation plaquettaire/effets des médicaments et des substances chimiques , Plaquettes/effets des médicaments et des substances chimiques , Plaquettes/métabolisme , Mâle , Thrombose/induit chimiquement , Souris , Activation plaquettaire/effets des médicaments et des substances chimiques , Adulte , Complexe glycoprotéique IIb-IIIa de la membrane plaquettaire/métabolisme , Coagulation sanguine/effets des médicaments et des substances chimiques , Souris de lignée C57BL , Sélectine P/métabolisme , Calcium/métabolisme , Calcium/sang , Nanoparticules/toxicité , Nanoparticules métalliques/toxicitéRÉSUMÉ
Water stress, a significant abiotic stressor, significantly hampers crop growth and yield, posing threat to food security. Despite the promising potential of nanoparticles (NPs) in enhancing plant stress tolerance, the precise mechanisms underlying the alleviation of water stress using O-Carboxymethyl chitosan nanoparticles (O-CMC-NPs) in maize remain elusive. In this study, we synthesized O-CMC-NPs and delved into their capacity to mitigate water stress (waterlogging and drought) in maize seedlings. Structural characterization revealed spherical O-CMC-NPs with a size of approximately 200 nm. These NPs accumulated near the seed embryo and root tip, resulting in a substantial increase in fresh and dry weights. The application of O-CMC-NPs to water-stressed maize seedlings remarkedly elevated the chlorophyll content and activity of various antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and polyphenol oxidase (PPO). The malondialdehyde (MDA) content was significantly reduced compared to the untreated control. Additionally, the expression of stress-responsive genes, such as ZmSOD, ZmCAT, ZmPOD, ZmTIFY, ZmACO, ZmPYL2, ZmNF-YC12, and ZmEREB180, were significantly upregulated in the O-CMC-NPs treated seedlings. These findings unveil the novel role of O-CMC-NPs in enhancing plant stress tolerance, suggesting their potential application in safeguarding maize seedlings under water stress conditions and facilitating the recovery from oxidative damage.
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Most studies on nanoplastics (NPs) focus on aquatic environments, overlooking their combined bioaccumulation with pollutants in terrestrial ecosystems. This study addresses a part of this gap by investigating how polystyrene nanoplastics (PS-NPs) affect the bioaccumulation and translocation of lead (Pb) in Hordeum vulgare L. plants. Using the RHIZOtest device for precise soil contamination control, we quantified PS-NPs (50 nm) in plant shoots via pyrolysis-gas chromatography/mass spectrometry (Py-GCMS) after plant KOH digestion. Our findings revealed that PS-NPs reduce Pb bioaccumulation and make adsorbed Pb onto PS-NPs less bioavailable to plants. For the highest Pb concentration, the Pb uptake index (PUI) followed the trend: Free Pb > NPs + Pb > Pb primary adsorbed by NPs, showing reduced Pb translocation to shoots in the presence of PS-NPs. Moreover, the presence of Pb decreased the bioavailability of PS-NPs probably in response to PS-NPs aggregation or modified charge. The PS-NPs concentrations in shoots range from 275.2 to 400 µg g-1, representing 3.9 to 5.75% of the total PS-NPs. This study highlights the intricate interactions between nanoplastics and metals in soil-plant systems and emphasizes the need for further research on their combined effects and potential risks to food safety.
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The current situation involves an increase in interest in nanotechnology, in particular the ways in which it can be applied in the commercial and medical fields. However, traditional methods of synthesizing nanoparticles have some drawbacks, including the generation of harmful byproducts, high energy consumption, and cost. As a result, researchers have shifted their focus to "green" nanoparticle synthesis to circumvent these drawbacks. Because of their exceptional physiochemical properties, silver nanoparticles (Ag Nps) are the noble metal nanoparticles that are used most frequently. The green approach to Ag NP synthesis is environmentally friendly, non-toxic, and cost-effective, and it makes use of a variety of biological entities. Cyanobacteria, in particular, have garnered the most attention because of the abundance of bioactive substances that they contain, which serve both as reducing agents and as stabilizing agents during the process of biosynthesis. This review article discusses the current state of cyanobacteria-mediated Ag NP synthesis, the potential mechanisms that are involved, nanoparticle characterization, the various applications of Ag NP in different fields, and their prospects.
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BACKGROUND: Tobacco mosaic virus (TMV) is a highly infectious plant virus that affects a wide variety of plants and reduces crop yields around the world. Here, we assessed the effectiveness of using Ammi visnaga aqueous seed extract to synthesize silver nanoparticles (Ag-NPs) and their potential to combat TMV. Different techniques were used to characterize Ag-NPs, such as scanning and transmission electron microscopy (SEM, TEM), energy-dispersive X-ray spectroscopy (EDS), fourier transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS). RESULTS: TEM demonstrated that the synthesized Ag-NPs had a spherical form with an average size of 23-30 nm and a zeta potential value of -15.9 mV, while FTIR revealed various functional groups involved in Ag-NP stability and capping. Interestingly, the Pre-treatment of tobacco plants (protective treatment) with Ag-NPs at 100-500 µg/mL significantly suppressed viral symptoms, while the Post-treatment (curative treatment) delayed their appearance. Furthermore, protective and curative treatments significantly increased chlorophyll a and b, total flavonoids, total soluble carbohydrates, and antioxidant enzymes activity (PPO, POX and CAT). Simultaneously, the application of Ag-NPs resulted in a decrease in levels of oxidative stress markers (H2O2 and MDA). The RT-qPCR results and volcano plot analysis showed that the Ag-NPs treatments trigger and regulate the transcription of ten defense-related genes (SbWRKY-1, SbWRKY-2, JERF-3, GST-1, POD, PR-1, PR-2, PR-12, PAL-1, and HQT-1). The heatmap revealed that GST-1, the primary gene involved in anthocyanidin production, was consistently the most expressed gene across all treatments throughout the study. Analysis of the gene co-expression network revealed that SbWRKY-19 was the most central gene among the studied genes, followed by PR-12 and PR-2. CONCLUSIONS: Overall, the reported antiviral properties (protective and/or curative) of biosynthesized Ag-NPs against TMV lead us to recommend using Ag-NPs as a simple, stable, and eco-friendly agent in developing pest management programs against plant viral infections.
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Nanoparticules métalliques , Nicotiana , Maladies des plantes , Extraits de plantes , Argent , Virus de la mosaïque du tabac , Virus de la mosaïque du tabac/physiologie , Argent/pharmacologie , Maladies des plantes/virologie , Maladies des plantes/génétique , Extraits de plantes/pharmacologie , Nicotiana/génétique , Nicotiana/virologie , Résistance à la maladie/génétique , Facteurs de transcription/génétique , Facteurs de transcription/métabolisme , Protéines végétales/génétique , Protéines végétales/métabolisme , Régulation de l'expression des gènes végétauxRÉSUMÉ
Cancers are increasing in prevalence and many challenges remain for their treatment, such as chemoresistance and toxicity. In this context, siRNA-based therapeutics have many potential advantages for cancer therapies as a result of their ability to reduce or prevent expression of specific cancer-related genes. However, the direct delivery of naked siRNA is hindered by issues like enzymatic degradation, insufficient cellular uptake, and poor pharmacokinetics. Hence, the discovery of a safe and efficient delivery vehicle is essential. This review explores various lipid and polymer-based delivery systems for siRNA in cancer treatment. Both polymers and lipids have garnered considerable attention as carriers for siRNA delivery. While all of these systems protect siRNA and enhance transfection efficacy, each exhibits its unique strengths. Lipid-based delivery systems, for instance, demonstrate high entrapment efficacy and utilize cost-effective materials. Conversely, polymeric-based delivery systems offer advantages through chemical modifications. Nonetheless, certain drawbacks still limit their usage. To address these limitations, combining different materials in formulations (lipid, polymer, or targeting agent) could enhance pharmaceutical properties, boost transfection efficacy, and reduce side effects. Furthermore, co-delivery of siRNA with other therapeutic agents presents a promising strategy to overcome cancer resistance. Lipid-based delivery systems have been demonstrated to encapsulate many therapeutic agents and with high efficiency, but most are limited in terms of the functionalities they display. In contrast, polymeric-based delivery systems can be chemically modified by a wide variety of routes to include multiple components, such as release or targeting elements, from the same materials backbone. Accordingly, by incorporating multiple materials such as lipids, polymers, and/or targeting agents in RNA formulations it is possible to improve the pharmaceutical properties and therapeutic efficacy while reducing side effects. This review focuses on strategies to improve siRNA cancer treatments and discusses future prospects in this important field.
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Metallic nanoparticles have gained attention in technological fields, particularly photonics. The creation of silver/gold (Ag/Au) alloy NPs upon laser exposure of an assembly of these NPs was described. First, using the Nd: YAG pulsed laser ablation's second harmonic at the same average power and exposure time, Ag and Au NPs in distilled water were created individually. Next, the assembly of Ag and Au NP colloids was exposed again to the pulsed laser, and the effects were examined at different average powers and exposure times. Furthermore, Ag/Au alloy nanoparticles were synthesized with by raising the average power and exposure time. The absorption spectrum, average size, and shape of alloy NPs were obtained by using an ultraviolet-visible (UV-Vis) spectrophotometer and transmission electron microscope instrument. Ag/Au alloy NPs have been obtained in the limit of quantum dots (<10 nm). The optical band gap energies of the Ag/Au alloy colloidal solutions were assessed for different Ag/Au alloy NP concentrations and NP sizes as a function of the exposure time and average power. The experimental data showed a trend toward an increasing bandgap with decreasing nanoparticle size. The nonlinear optical characteristics of Ag/Au NPs were evaluated and measured by the Z-scan technique using high repetition rate (80 MHz), femtosecond (100 fs), and near-infrared (NIR) (750-850 nm) laser pulses. In open aperture (OA) Z-scan measurements, Ag, Au, and Ag/AuNPs present reverse saturation absorption (RSA) behavior, indicating a positive nonlinear absorption (NLA) coefficient. In the close-aperture (CA) measurements, the nonlinear refractive (NLR) indices (n2) of the Ag, Au, and Ag/Au NP samples were ascribed to the self-defocusing effect, indicating an effective negative nonlinearity for the nanoparticles. The NLA and NLR characteristics of the Ag/Au NPs colloids were found to be influenced by the incident power and excitation wavelength. The optical limiting (OL) effects of the Ag/Au alloy solution at various excitation wavelengths were studied. The OL effect of alloy NPs is greater than that of monometallic NPs. The Ag/Au bimetallic nanoparticles were found to be more suitable for optical-limiting applications.