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1.
Int J Biol Macromol ; 261(Pt 2): 129801, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38309410

RESUMEN

This work aims to enhance the performance of the polyvinyl alcohol (PVA) composite by using cellulose nanocrystal (CNC) as reinforcement and copper nanoparticles (CuNPs)/reduced graphene oxide (rGO) as conducting and antimicrobial reagents. Firstly, rGO was loaded onto CuNPs using an eco-friendly microwave method. Different techniques characterized the components and prepared composites, which indicated the incorporation of cellulose nanocrystals and rGO@CuNPs within the polyvinyl alcohol matrix. Utilizing the clear zone of inhibition, the antibacterial test was quantified. Compared to the neat composite, the rGO@CuNPs loaded polyvinyl alcohol/ cellulose nanocrystal composites exhibited no bacterial growth against S. aureus, E. coli, and C. albicans. However, all composites did not have antifungal activity against A. niger. The combination of conductivity and interfacial polarization is the reason for the abrupt increase of permittivity with decreasing frequency. Besides, adding rGO@CuNPs improved the electrical conductivity. DC-Conductivity increased about a decade after adding cellulose nanocrystal to polyvinyl alcohol, then another decade after adding CuONPs. The electric loss modulus representation shows a systematic shift in the peak position towards higher frequencies, decreasing the so-called conductivity relaxation time. This is the main reason for the enhancement of conductivity. The systematic attenuation of peaks' height with increasing conductivity is still unclear.


Asunto(s)
Grafito , Nanocompuestos , Nanopartículas , Alcohol Polivinílico/química , Celulosa/química , Escherichia coli , Staphylococcus aureus , Nanocompuestos/química , Nanopartículas/química , Antibacterianos/farmacología , Antibacterianos/química
2.
Toxicol Res (Camb) ; 13(3): tfae091, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38873278

RESUMEN

Several studies showed the adverse effects of amoxicillin on various body organs. So, this research has been designed to evaluate the modulatory role of Ashwagandha seed extract (ASE) against amoxicillin (AM) toxicity. Rats treated with AM (90 mg/kg), protected by ASE doses (100, 200 and 300 mg/kg), and treated by ASE at the same three doses. At the end of the experimental period, DNA comet assay, cytogenetic examinations, sperm-shape analysis, evaluation of the malondialdehyde (MDA) percentages, histopathological examinations, and biophysical tests (modulus, relaxation time, permittivity, entropy, and internal energy change of brain) were documented. The results confirmed that AM treatment induced significant elevation of DNA damage, cytogenetic aberrations, and MDA content in brain, liver, and testis tissues and sperm-shape anomalies. ASE treatment significantly minimized the genetic changes, sperm-shape anomalies, and MDA generation. These enhancements were more pronounced by protective ASE and increased by increasing the dose level. In histopathological examinations, AM treatment caused neurotoxicity in brain tissue. ASE treatment, partially, minimized these damages and the positive effects of therapeutic ASE were more noticeable. Biophysical parameters showed that therapeutic ASE was better for relaxation time, permittivity, and free energy change. Protective and therapeutic ASE were able to recover entropy and internal energy changes in variant degrees.

3.
Appl Radiat Isot ; 196: 110776, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36947911

RESUMEN

This research article introduces dielectric and thermodynamic state functions as physical markersdetecting both radiation effects and biological repairs to such damages. The red blood cells of rats were physically investigated in this work after whole body irradiation by 7 Gy of gamma rays and trying for reducing the damage effect of ionizing radiation by using the one of the best medicinal plants, Moringa leaves, which are rich with plentiful amounts of antioxidants and nutrients. The animals were divided into six groups; control, Moringa, irradiated, protected, treated, pro-treated. The physical parameters measured were impedance and DC conductivity then, relaxation time, activation energy and enthalpy change were calculated. Most of these parameters showed that the damage occurred in RBCs membrane due to ionizing radiation needs more than four weeks after irradiation to recover. As dipolar relaxation required much more time to occur and charge conduction were greatly reduced.


Asunto(s)
Moringa , Ratas , Animales , Eritrocitos/efectos de la radiación , Antioxidantes/farmacología , Rayos gamma , Extractos Vegetales/farmacología , Hojas de la Planta
4.
Prog Biophys Mol Biol ; 140: 150-154, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29885347

RESUMEN

This work has a major interest of the use of Moringa oleifera leaves extract as protective and protective-therapeutic natural supplement helping the biosystem to stand against irradiation induced damage. Rats were orally administered with Moringa oleifera leaves extract by two modalities. The dielectric properties were measured over the frequency range 106 - 2 × 108 Hz and in the temperature window 283-313 K. The dielectric parameters were used to estimate some thermodynamic state functions and evaluate the energy within the Hb molecule. Information source will be the least invasive way consuming haemoglobin from blood sample. Results indicated that some physical parameters were better indicators than others and different modalities showed variant outcomes. In addition, administration of moringa leaves extract proved to have a significant effect that can be used to reduce radiation damage which may be due to constituents of Moringa.


Asunto(s)
Hemoglobinas/metabolismo , Moringa oleifera/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Protectores contra Radiación/farmacología , Animales , Impedancia Eléctrica , Femenino , Ratas , Ratas Wistar , Termodinámica
5.
Prog Biophys Mol Biol ; 140: 74-78, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29729329

RESUMEN

In this paper we'll shed some light on well-known physical parameters to introduce them as new tools, biophysical markers, for diagnosis and prognosis of the molecular, cellular, tissue and organ biosystems such as Haemoglobin representing the macromolecules' category. Where the data reveal a lot of information about the effect of radiation dose rate on the macromolecule that are not discovered by conventional ways. Also, data put forward the dielectric and thermodynamical parameters and classify them as premiers and superiors for the detection of any disturbance that occurs in the electrical homogeneity of the macromolecule. The interesting results showed an inverse response of the Hb molecule toward higher and lower dose rates for all tested parameters, Static permittivity and change in the following thermodynamical state functions Helmholtz free energy, internal energy and entropy.


Asunto(s)
Entropía , Hemoglobinas/metabolismo , Dosis de Radiación , Animales , Femenino , Radiometría , Ratas , Ratas Wistar
6.
Prog Biophys Mol Biol ; 140: 142-149, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29885346

RESUMEN

It has been found that medicinal plants have chemical and/or therapeutic effects on different diseases related to oxidative damage. This work investigates the use of ethanolic Moringa oleifera leaves extract; as a protective and/or therapeutic agent against damage induced by high acute dose of ionizing radiation. Also, this study aims to explore the associations of electrical properties (relaxation time and DC conductivity of bone marrow) with biochemical markers (SOD, CAT and GSH) to detect and prognosticate radiation effects. Biophysical and biochemical data revealed that Moringa extract can improve the electrical properties of bone marrow and the antioxidants levels in the blood. They also showed that the feeding of Moringa leaves extract post irradiation is preferred to recover rapidly and continuously from radiation effects.


Asunto(s)
Moringa oleifera/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Protectores contra Radiación/farmacología , Animales , Antioxidantes/metabolismo , Médula Ósea/efectos de los fármacos , Médula Ósea/metabolismo , Médula Ósea/efectos de la radiación , Catalasa/metabolismo , Impedancia Eléctrica , Femenino , Glutatión/metabolismo , Ratas , Ratas Wistar , Superóxido Dismutasa/metabolismo
7.
Prog Biophys Mol Biol ; 140: 124-132, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29776659

RESUMEN

The response of adult Wistar albino female rats toward two dose rates of gamma radiation delivered as acute dose of 7 Gy is investigated using classical methodologies as chemical, hematological and histological parameters in comparison with newly introduced dielectric parameters. Two groups of rats were exposed to γ ray with dose rates 533.35 mGy/min and 325.89 mGy/min. Then the irradiated groups were followed up for two weeks after irradiation. In case of higher dose rate, high percentage of animals was lost and there were substantial alterations in the dielectric parameters in addition to massive damage in liver and bone marrow cells. On the other hand, a reduction of death rate of rats, different behavior in the dielectric parameters of bone marrow and lesser injury of liver tissue were well noticeable in case of lower dose rate. Moreover, the sensitivity of dielectric parameters toward the two different dose rates was well pronounced during the 1st and 2nd weeks after irradiation more than other parameters.


Asunto(s)
Médula Ósea/efectos de la radiación , Dosis de Radiación , Animales , Relación Dosis-Respuesta en la Radiación , Impedancia Eléctrica , Femenino , Rayos gamma/efectos adversos , Pruebas Hematológicas , Hígado/inmunología , Hígado/efectos de la radiación , Ratas , Ratas Wistar
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