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1.
J Mater Sci Mater Electron ; 34(4): 318, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38625312

RESUMO

For the first time, the influence of Cerium (Ce3+) on the structural, microstructural, Fourier infrared spectroscopy, and LPG sensing behaviour of CoCr2-xCexO4 (CoCrCe) is described in this study. The solution combustion technique was used to create the CoCrCe samples. All samples were sintered for 3 h at 600 °C to achieve a pure crystalline nature free of impurities. The production of cubic spinel structures with typical crystallite sizes smaller than 16 nm is confirmed by X-ray diffraction. Because compressive lattice strain is created when Ce3+ ions are replaced by Cr3+ ions, we discovered reducing the lattice parameter. Further samples were analysed using the FTIR technique to learn about the octahedral and tetrahedral stretching bands, which confirmed the ferrite structure was free of impurities. Scanning Electron microscopy was used to examine the samples' microstructures. All of the samples were determined to be very porous. Elemental analysis was performed using energy dissipative spectra, which confirmed the presence of all elements in the samples. 2-mol% Ce3+ has the best gas sensing characteristics of any Ce concentration. Furthermore, the thin film based on CoCr1.98Ce0.02O4 may be employed as a chemiresistive gas sensor to detect LPG (10-1000 ppb) at room temperature. On LPG exposure, the constructed gas sensor demonstrates greater gas sensitivity in the order of 98% at 500 ppb, with higher stability, rapid response, and recovery time in the order of 60 s and 75 s, respectively. This study reports for the first time on the creation of an LPG gas sensor device that operates at room temperature and has high sensitivity. Because of their high gas sensitivity, rapid reaction and recovery times, and long-term stability, these material gas sensors might be ideal materials for the manufacture of gas sensors devices for the detection of LPG low concentration (ppb level).

2.
Front Microbiol ; 15: 1260793, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38440135

RESUMO

Gut microbiota dysbiosis has been a serious risk factor for several gastric and systemic diseases. Recently, gut microbiota's role in aging was discussed. Available preclinical evidence suggests that the probiotic bacteria Lactiplantibacillus plantarums (LP) may influence the aging process via modulation of the gut microbiota. The present review summarized compelling evidence of LP's potential effect on aging hallmarks such as oxidative stress, inflammation, DNA methylation, and mitochondrial dysfunction. LP gavage modulates gut microbiota and improves overall endurance in aging animal models. LP cell constituents exert considerable antioxidant potential which may reduce ROS levels directly. In addition, restored gut microbiota facilitate a healthy intestinal milieu and accelerate multi-channel communication via signaling factors such as SCFA and GABA. Signaling factors further activate specific transcription factor Nrf2 in order to reduce oxidative damage. Nrf2 regulates cellular defense systems involving anti-inflammatory cytokines, MMPs, and protective enzymes against MAPKs. We concluded that LP supplementation may be an effective approach to managing aging and associated health risks.

3.
Int J Biol Macromol ; 261(Pt 1): 129692, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38278398

RESUMO

H2O2-modified graphite schist (GS) and sodium alginate (SA) interface was loaded by Fe3O4 nanoparticles (MNPs) to prepare a magnetic biosorbent that was employed in removing Mn(VII) from solutions. The prepared GS/SA/MNPs adsorbent was investigated using a variety of techniques, including elemental mapping, TEM, XPS, FTIR, FESEM, EDX, XRD, XPS, and zeta potential. An experimental study supported by statistical physics calculations was carried out to obtain a new outline of the Mn(VII) uptake mechanism. The classical Freundlich and the statistical physical double-layer models adequately described the Mn(VII) uptake process at pH 3.0 and a temperature of 25-55 °C. The removed number of Mn ions (such as Mn+7 and Mn+2) per GS/SA/MNPs active site ranged from 0.70 to 0.84, indicating a mixed adsorption orientation driven by surface complexation and attraction forces mechanisms. The adsorption energies (∆E) calculated by the double-layer model ranged from 18.79 to 24.94 kJ/mol, suggesting that the interaction between Mn(VII) and GS/SA/MNPs was controlled by physical forces. Increasing the adsorption capacity at saturation (Qsat) from 333.14 to 369.52 mg/g with temperature proposed an endothermic capture process. Thermodynamic functions clarified the viability and spontaneity of Mn(VII) uptake on the GS/SA/MNPs adsorbent.


Assuntos
Grafite , Poluentes Químicos da Água , Grafite/química , Poluentes Químicos da Água/química , Alginatos/química , Peróxido de Hidrogênio , Adsorção , Magnetismo , Fenômenos Magnéticos , Concentração de Íons de Hidrogênio , Cinética
4.
Artigo em Inglês | MEDLINE | ID: mdl-36874615

RESUMO

Paclitaxel is a primary chemotherapy agent that displays antitumor activity against a variety of solid tumors. However, the clinical effectiveness of the drug is hampered by its nephrotoxic and cardiotoxic side effects. Thus, this investigation aimed at assessing the protective effects of rutin, hesperidin, and their combination to alleviate nephrotoxicity caused by paclitaxel (Taxol), cardiotoxicity in male Wistar rats, as well as oxidative stress. Rutin (10 mg/kg body weight), hesperidin (10 mg/kg body weight), and their mixture were given orally every other day for six weeks. Rats received intraperitoneal injections of paclitaxel twice weekly, on the second and fifth days of the week, at a dose of 2 mg/kg body weight. In paclitaxel-treated rats, the treatment of rutin and hesperidin decreased the elevated serum levels of creatinine, urea, and uric acid, indicating a recovery of kidney functions. The cardiac dysfunction in paclitaxel-treated rats that got rutin and hesperidin treatment also diminished, as shown by a substantial reduction in elevated CK-MB and LDH activity. Following paclitaxel administration, the severity of the kidney and the heart's histopathological findings and lesion scores were markedly decreased by rutin and hesperidin administration. Moreover, these treatments significantly reduced renal and cardiac lipid peroxidation while markedly increased GSH content and SOD and GPx activities. Thus, paclitaxel likely induces toxicity in the kidney and the heart by producing oxidative stress. The treatments likely countered renal and cardiac dysfunction and histopathological changes by suppressing oxidative stress and augmenting the antioxidant defenses. Rutin and hesperidin combination was most efficacious in rescuing renal and cardiac function as well as histological integrity in paclitaxel-administered rats.

5.
Sci Rep ; 12(1): 22133, 2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36550138

RESUMO

We have designed a unique structure for a liquid sensor based on two-dimensional PCs with a triangular lattice constant in the periodicity by drilling a hexagonal cylinder in a dielectric host material. Using the COMSOL multiphysics approach, we investigated the given structure and sensing performance based on the finite element method. We will optimize two-dimensional hexagonal photonic crystals to localize the photonic band gap region in the mid and far infra-red frequency range, as water is a good absorber for this range of frequencies. Then, we inject the central hexagonal cylinder with saline water and calculate the sensor parameters for different values of the refractive index of saline water at different frequencies related to photonic band gaps. We could reach the optimum conditions of the salinity sensor as the half diagonal of the hexagonal shape (R) = 500 nm, the perpendicular distance between the two diagonal hexagonal (D) = 250 nm, and the number of periods (N) = 5, which gives a high efficiency with sensitivity (S) = 525 nm/RIU, figure of merit (FOM) = 80.7 RIU-1, and quality factor (Q) = 375. The effects of structural characteristics on sensing performance are investigated, with new approaches for improving salinity sensors proposed. Furthermore, traditional salinity sensors may be replaced by the proposed method in the photo-sensing application, which is simple and practical for use in the thermal desalination techniques.

6.
RSC Adv ; 10(53): 31765-31772, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-35518172

RESUMO

A new biophotonic sensor based on photonic crystal (PC) has been designed for the detection of creatinine concentration in blood, and is considered an important small molecule biomarker of renal dysfunction. Based on the transfer matrix method (TMM), we theoretically investigated the transmittance spectra of a one dimensional alternating dielectric photonic crystal (PC) designed as (AB)7/C/(AB)7 made of MgF2 (A), CeO2 (B) and creatinine concentration present in blood (C). The transmission spectra exhibit resonant peaks within the photonic band gap (PBG) indicative of so-called defect modes, which depend on parameters, such as concentration of creatinine in blood, thickness of defect layer and incident angle. The proposed sensor can determine the physiological levels of creatinine in human blood serum samples. The estimated parameters realize an efficient biophotonic sensor wherein sensitivity was tuned from 136.4 nm per RIU to 306.25 nm per RIU and is very useful for the detection of creatinine.

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