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1.
Opt Express ; 31(17): 27880-27893, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710854

RESUMO

This paper presents an innovative design that combines the functionalities of a polarization convertor and an electromagnetic (EM) radiator into a single integrated metasurface. The metasurface consists of two identical metallic split-rings, a circular-shaped patch structure, a dielectric layer, and a reflective metallic ground. The polarization convertor component efficiently converts waves polarized in the x- or y-direction into cross-polarized waves within a frequency range of 8-13 GHz. It exhibits wideband resonances and achieves a high conversion efficiency. In the context of low-observable platforms, traditional high-gain antennas often suffer from a large radar cross section (RCS). To overcome this challenge, the same metasurface is utilized for EM radiation, enabling a high gain of 16.5 dBi while maintaining a low RCS. This is accomplished by strategically rotating the double-slotted metallic split-rings at 90 ∘, 180 ∘, and 270 ∘ in four distinct regions. Through this rotation, destructive interference cancellation occurs, resulting in wideband reduction of the RCS. Experimental results validate the effectiveness of the proposed metasurface in serving both applications, namely polarization conversion and EM radiation.

2.
Environ Res ; 223: 115429, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36746207

RESUMO

Cellulose is the most abundant polysaccharide on earth. It has a large number of desirable properties. Its low toxicity makes it more useful for a variety of applications. Nowadays, its composites are used in most engineering fields. Composite consists of a polymer matrix and use as a reinforcing material. By reducing the cost of traditional fibers, it has an increasing demand for environment-friendly purposes. The use of these types of composites is inherent in moisture absorption with hindered natural fibers. This determines the reduction of polymer composite material. By appropriate chemical surface treatment of cellulose composite materials, the effect could be diminished. The most modern and advanced techniques and methods for the preparation of cellulose and polymer composites are discussed here. Cellulosic composites show a reinforcing effect on the polymer matrix as pointed out by mechanical characterization. Researchers tried their hard work to study different ways of converting various agricultural by-products into useful eco-friendly polymer composites for sustainable production. Cellulose plays building blocks, that are critical for polymer products and their engineering applications. The most common method used to prepare composites is in-situ polymerization. This help to increase the yields of cellulosic composites with a significant enhancement in thermal stability and mechanical properties. Recently, cellulose composites used as enhancing the incorporation of inorganic materials in multi-functional properties. Furthermore, we have summarized in this review the potential applications of cellulose composites in different fields like packaging, aerogels, hydrogels, and fibers.


Assuntos
Celulose , Polímeros , Celulose/química , Estudos Prospectivos
3.
Environ Res ; 219: 115091, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36529323

RESUMO

Textile and printing industries play a vital role in the economy of any country. But the effluents of these industries, which contain toxic Methylene Blue (MB) dye when mixed with fresh water, make it unfit for human health and aquatic life. For the removal of MB, different adsorbents were used, but they were expensive, non-biodegradable or less effective. In this research, novel carboxymethyl starch grafted poly 2-carboxyethyl acrylate (CM-St-g-P2CEtA) was synthesized by reacting carboxymethyl starch with 2-carboxyethyl acrylate. The reaction followed a free radical polymerization mechanism. The structure and properties of CM-St-g-P2CEtA were investigated by advanced analytical techniques. The CM-St-g-P2CEtA was employed for the remediation of Methylene Blue (MB) dye from wastewater. The removal percentage (%R) of MB was checked under different parameters, like different pH levels, different initial concentrations of dye, different adsorbent doses, and different contact times. The results obtained during the experiment were subjected to different adsorption and kinetic models. In the kinetic investigation, the experimental results were best represented by the pseudo-second-order kinetic model due to its high R2 value of 0.999. Similarly, with a regression coefficient (R2) value of 0.947, the Langmuir adsorption isotherm was best represented by the experimental results. The Langmuir adsorption model showed that MB dye was adsorbed on the surface of CM-St-g-P2CEtA in a monolayer pattern. The pseudo 2nd order kinetic model suggested that the adsorption process favored chemisorption mechanism. The CM-St-g-P2CEtA showed maximum percentage removal efficiency (%R) of 99.3% for MB dye.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Humanos , Azul de Metileno/química , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Adsorção , Cinética
4.
Environ Res ; 222: 115253, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36702191

RESUMO

Epoxy resins are important thermosetting polymers. They are widely used in many applications i.e., adhesives, plastics, coatings and sealers. Epoxy molding compounds have attained dominance among common materials due to their excellent mechanical properties. The sol-gel simple method was applied to distinguish the impact on the colloidal time. The properties were obtained with silica-based fillers to enable their mechanical and thermal improvement. The work which we have done here on epoxy-based nanocomposites was successfully modified. The purpose of this research was to look into the effects of cellulose nanocrystals (CNCs) on various properties and applications. CNCs have recently attracted a lot of interest in a variety of industries due to their high aspect ratio, and low density which makes them perfect candidates. Adding different amounts of silica-based nanocomposites to the epoxy system. Analyzed with different techniques such as Fourier-transformed infrared spectroscope (FTIR), thermogravimetric analysis (TGA) and scanning electronic microscopic (SEM) to investigate the morphological properties of modified composites. The various %-age of silica composite was prepared in the epoxy system. The 20% of silica was shown greater enhancement and improvement. They show a better result than D-400 epoxy. Increasing the silica, the transparency of the films decreased, because clustering appears. This shows that the broad use of CNCs in environmental engineering applications is possible, particularly for surface modification, which was evaluated for qualities such as absorption and chemical resistant behavior.


Assuntos
Celulose , Nanopartículas , Celulose/química , Celulose/ultraestrutura , Porosidade , Água/química , Dióxido de Silício/química , Nanopartículas/química
5.
Molecules ; 28(17)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37687068

RESUMO

Efficient and excellent nanoparticles are required for the degradation of organic dyes in photocatalysis. In this study, silver-manganese oxide nanoparticles (Ag-Mn-NPs) were synthesized through a wet chemical precipitation method and characterized as an advanced catalyst that has enhanced photocatalytic activity under sunlight irradiation. The nanoparticles were characterized using scanning electron microscopy (SEM), XRD, UV-vis light spectra, and energy-dispersive X-ray (EDX) spectroscopy, revealing their spherical and agglomerated form. The EDX spectra confirmed the composition of the nanoparticles, indicating their presence in oxide form. These bimetallic oxide nanoparticles were employed as photocatalysts for the degradation of malachite green (MG) dye under sunlight irradiation in an aqueous medium. The study investigated the effects of various parameters, such as irradiation time, catalyst dosage, recovered catalyst dosage, dye concentration, and pH, on the dye's photodegradation. The results showed that Ag-Mn oxide nanoparticles exhibited high photocatalytic activity, degrading 92% of the dye in 100 min. A longer irradiation time led to increased dye degradation. Moreover, a higher catalyst dosage resulted in a higher dye degradation percentage, with 91% degradation achieved using 0.0017 g of the photocatalyst in 60 min. Increasing the pH of the medium also enhanced the dye degradation, with 99% degradation achieved at pH 10 in 60 min. However, the photodegradation rate decreased with increasing dye concentration. The Ag-Mn oxide nanoparticles demonstrate excellent potential as a reliable visible-light-responsive photocatalyst for the efficient degradation of organic pollutants in wastewater treatment.

6.
Environ Res ; 215(Pt 1): 114241, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36100100

RESUMO

This study is based on the removal of methylene blue (MB) from aqueous solution by cost effective and biodegradable adsorbent carboxymethyl starch grafted polyvinyl pyrolidone (Car-St-g-PVP). The Car-St-g-PVP was synthesized by grafting vinyl pyrolidone onto carboxymethyl starch by free radical polymerization reaction. The structure and different properties of Car-St-g-PVP were determined by 1H NMR, FT-IR, XRD, TGA and SEM. A series of batch experiments were conducted for the removal of MB, The adsorption affecting factors such as temperature, contact time, initial concentration of MB dye, dose of Car-St-g-PVP and pH were studied in detail. The other parameters like the thermodynamic study, kinetics and isothermal models were fitted to the experimental data. The results showed that pseudo 2nd order kinetics and Langmuir's adsorption isotherms were best fitted to experimental data with regression coefficient R2 viz. 0.99 and 0.97. The kinetic study showed that the adsorption mechanism favored chemisorption. The Gibbs free energy (ΔG°) for the adsorption process was found to be -7.31 kJ/mol, -8.23 kJ/mol, -9.00 kJ/mol and -10.10 kJ/mol at 25 °C, 35 °C, 45 °C and 55 °C respectively. The negative values of ΔG° suggested the spontaneous nature of the adsorption process. Similarly, the positive values of entropy (ΔS°) and enthalpy (ΔH°) 91.27 J/k.mol and 19.90 kJ/mol showed the increasing randomness and endothermic nature of the adsorption process. The value of separation factor (RL) was found to be less than one (RL < 1), which supported the feasibility of the adsorption process. The maximum MB removal percentage (% R) was found to be 98.6%. So, these findings show that Car-St-g-PVP can be meritoriously used for the treatment of MB from wastewater.


Assuntos
Azul de Metileno , Poluentes Químicos da Água , Adsorção , Ácidos Carboxílicos , Concentração de Íons de Hidrogênio , Cinética , Azul de Metileno/química , Polivinil , Povidona , Espectroscopia de Infravermelho com Transformada de Fourier , Amido , Termodinâmica , Águas Residuárias
7.
Molecules ; 27(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36144579

RESUMO

In this research, a new biodegradable and eco-friendly adsorbent, starch-grafted polymethyl methacrylate (St-g-PMMA) was synthesized. The St-g-PMMA was synthesized by a free radical polymerization reaction in which methyl methacrylate (MMA) was grafted onto a starch polymer chain. The reaction was performed in water in the presence of a potassium persulfate (KPS) initiator. The structure and different properties of the St-g-PMMA was explored by FT-IR, 1H NMR, TGA, SEM and XRD. After characterization, the St-g-PMMA was used for the removal of MB dye. Different adsorption parameters, such as effect of adsorbent dose, effect of pH, effect of initial concentration of dye solution, effect of contact time and comparative adsorption study were investigated. The St-g-PMMA showed a maximum removal percentage (R%) of 97% towards MB. The other parameters, such as the isothermal and kinetic models, were fitted to the experimental data. The results showed that the Langmuir adsorption and pseudo second order kinetic models were best fitted to experimental data with a regression coefficient of R2 = 0.93 and 0.99, respectively.


Assuntos
Azul de Metileno , Poluentes Químicos da Água , Adsorção , Radicais Livres , Gentamicinas , Concentração de Íons de Hidrogênio , Cinética , Metacrilatos , Metilmetacrilatos , Polimerização , Polimetil Metacrilato , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Água , Poluentes Químicos da Água/química
8.
Pak J Pharm Sci ; 31(1): 37-44, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29348082

RESUMO

Aminoglycosides are the commonly used antibiotics against Gram negative bacteria. Their clinical applications are limited due to nephrotoxic side effects. Therefore, the current study was undertaken in an attempt to increase the use of these drugs without causing nephrotoxicity by exploring the nephroprotective effects of a medicinal plant with high flavonoid contents and strong antioxidant properties, namely Valeriana wallichii. A daily dose of 200mg/kg of the extract derived from V. wallichii was employed for a period of three weeks. The results obtained revealed that co-therapy of extract with gentamicin protected some changes in renal functions; however, failed to provide a complete protection as assessed by biochemical, physiological and histological parameters. It can be concluded from the current findings that V. wallichii failed to deliver protective effects against gentamicin induced renal damage in spite of strong flavonoid contents and antioxidant properties.


Assuntos
Antibacterianos/efeitos adversos , Antioxidantes/farmacologia , Gentamicinas/efeitos adversos , Rim/efeitos dos fármacos , Extratos Vegetais/farmacologia , Valeriana/química , Animais , Antioxidantes/isolamento & purificação , Eletrólitos/sangue , Enzimas/urina , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Rim/metabolismo , Rim/patologia , Testes de Função Renal , Extratos Vegetais/isolamento & purificação , Proteinúria/induzido quimicamente , Coelhos , Rizoma/química , Urinálise
9.
Molecules ; 22(10)2017 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-29065448

RESUMO

In herbalism, botanical supplements are commonly believed to be safe remedies, however, botanical supplements and dietary ingredients interact with transport and metabolic processes, affecting drug disposition. Although a large number of studies have described that botanical supplements interfere with drug metabolism, the mode of their interaction with drug transport processes is not well described. Such interactions may result in serious undesired effects and changed drug efficacy, therefore, some studies on interaction between botanical supplement ingredients and drug transporters such as P-gp and OATPs are described here, suggesting that the interaction between botanical supplements and the drug transporters is clinically significant.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Suplementos Nutricionais/efeitos adversos , Interações Ervas-Drogas , Neoplasias Hepáticas/tratamento farmacológico , Carcinoma Hepatocelular/dietoterapia , Carcinoma Hepatocelular/patologia , Humanos , Intestinos/efeitos dos fármacos , Intestinos/patologia , Neoplasias Hepáticas/dietoterapia , Neoplasias Hepáticas/patologia , Fitoterapia/efeitos adversos , Fitoterapia/métodos
10.
Pak J Pharm Sci ; 30(1): 55-60, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28603113

RESUMO

Cinnamomum zeylanicum has strong antioxidant properties and has been presented to have nephroprotective effects. Present work was aimed to study the nephroprotective property of the plant extract through urinary enzymes excretion, to confirm its protective effects and to observe the antibacterial activities of gentamicin in combination with the plant extract. 200mg/kg/day of the plant extracts were administered alone and as co-therapy with gentamicin. Urinary lactate dehydrogenase (LDH) and Urinary alkaline phospatase (ALP) excretions were observed through reagents kits with the help of Power-Lab 300. Antibacterial activities were assessed for gentamicin alone and in combination with the extract. Present study showed that the plant extract have excess quantity of flavonoids, which may responsible for attenuating the excessive excretion of urinary LDH. However, Urinary ALP excretion was found remained same throughout the study period in all experimental groups; might be detected in acute damage. Further, the plant also proved to have no decreasing impact on the antibacterial activities of gentamicin.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Cinnamomum zeylanicum/química , Gentamicinas/farmacologia , Rim/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Agentes Urológicos/farmacologia , Fosfatase Alcalina/urina , Animais , Antibacterianos/isolamento & purificação , Bactérias/crescimento & desenvolvimento , Citoproteção , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Quimioterapia Combinada , Rim/enzimologia , L-Lactato Desidrogenase/urina , Compostos Fitoquímicos/isolamento & purificação , Fitoterapia , Plantas Medicinais , Coelhos , Agentes Urológicos/isolamento & purificação
11.
Pharm Biol ; 54(3): 530-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26067678

RESUMO

CONTEXT: Morus alba L. (Moraceae) is traditionally used for the treatment of urinary incontinency due its strong diuretic properties. OBJECTIVE: The present study explores the renal protective effects of M. alba, due to its free radical scavenging properties, in order to provide experimental evidence for its established use. MATERIALS AND METHODS: Ethanolic extract (200 mg/kg/d) derived from M. alba fruit was employed in rabbits as a co-therapy (GM-al) with gentamicin (80 mg/kg/d) for a period of 3 weeks. Biochemical kidney functioning parameters, urinary isozymes, and histopathological examination were performed. RESULTS: The results showed that ethanol extract of Morus alba L. prevented alterations in serum creatinine (4.02 ± 0.14, p < 0.0001), blood urea nitrogen (54.18 ± 2.60, p < 0.0001), and serum uric acid levels (2.34 ± 0.12, p < 0.001). However, a decrease in creatinine clearance and urinary volume was observed in experimental groups. Histopathological examination and urinary enzymes excretion also suggested the protective role of the extract. DISCUSSION AND CONCLUSIONS: The co-administration of M. alba with gentamicin prevented renal functioning alterations expected with the use of gentamicin alone. Therefore, it can be concluded that M. alba to protect from kidney damage, which may be because of its free radical scavenging and diuretic properties.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Sequestradores de Radicais Livres/farmacologia , Rim/efeitos dos fármacos , Rim/metabolismo , Morus , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Sequestradores de Radicais Livres/isolamento & purificação , Frutas , Gentamicinas/toxicidade , Rim/patologia , Masculino , Estudos Prospectivos , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/farmacologia , Coelhos
12.
Acta Pol Pharm ; 72(4): 651-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26647620

RESUMO

The kidneys are important organs which have many functions in the body, including the production of hormones, absorbtion of minerals and the filtration of blood, producing urine. Their failure can be fatal, therefore, to focus the study of such herbs which may be useful in treating renal disease is the need of hour. In Pakistan, Cucumis melo and Berberis vulgaris has been commonly used for renal problems. In both of these plants were found flavonoids, alkaloids and terpenes, which may stand for their renal protective properties. Their reported vitamin E contents and antioxidant potentials also provide a base for their defensive mechanism, may be due to their free radical scavenging properties. Further, their diuretic and urinary tract anti-ulcer properties also support their traditional use in renal diseases. Their anti-histaminic and anti-cholinergic properties also provide symptomatic treatment by decreasing prostaglandin level and due to antispasmodic properties. Concluding, both of these plants can be used for renal problems, especially Cucumis melo, which have both the nutritive and medicinal properties. Therefore, the renal disease patients are advised to take much of this particular fruit, especially their seeds to make their kidneys healthy.


Assuntos
Berberis , Cucumis melo , Nefropatias/tratamento farmacológico , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Humanos , Paquistão , Estudos Prospectivos
13.
Pharm Biol ; 2014 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-24417619

RESUMO

Abstract Context: Gentamicin is an antibiotic that is effective against Gram-negative microorganisms. However, its clinical applications are often limited due to nephrotoxic effects. Objective: This study investigated the protective effects of aqueous-ethanol extract of Tamarindus indica L. (Leguminosae) fruits against gentamicin-induced renal toxicity. Materials and methods: A daily dose of 200 mg/kg of 70% aqueous-ethanol extract derived from T. indica was employed in male rabbits as a co-therapy with gentamicin (80 mg/kg) for a period of three weeks. Serum and urinary renal function parameters and histological assessments were carried out and compared with one way analysis of variance (Graphpad prism version 5.00, Graphpad Software, San Diego, CA). Results: The results showed that gentamicin-treated animals had significantly elevated blood urea nitrogen (54.1 ± 2.6 mg/dl), serum creatinine (4.0 ± 0.1 mg/dl), serum uric acid (2.3 ± 0.1 mg/dl) and urinary protein excretion (3.8 ± 0.3 mg/dl) with a fall in body weight (10 ± 1%), creatinine clearance (0.7 ± 0.09 ml/min), serum potassium (3.4 ± 0.1 mEq/l), serum calcium (7.6 ± 0.2 mg/dl), urinary volume (126 ± 9 ml/24 h) and urinary lactate dehydrogenase secretion (103.1 ± 4.2 U/l). However, animals treated by co-therapy with gentamicin and T. indica had significantly improved renal structure and function. Discussion and conclusion: Co-therapy of 200 mg/kg/d of T. indica for a period of three weeks successfully prevented functional and morphological derangements caused by gentamicin as assessed by different renal function parameters and histological examinations.

14.
Pak J Pharm Sci ; 27(3): 505-10, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24811809

RESUMO

Citrus aurantium is traditionally used in various kidney problems like burning of urine, urinary hesitancy and renal colic. The main objective of the present work was to evaluate the protective role of Citrus aurantium against gentamicin induced renal damage, due to its free radical scavenging properties to present experimental facts for their traditional use. 200 mg/kg/day of ethanolic extract of the plant employed in combination with the toxic doses of gentamicin for twenty-one days. The group GC-au (animals treated with co-administration of Citrus aurantium and gentamicin) protected renal damage expected with gentamicin, assessed by known functional and morphological parameters, significantly different from group G (animals treated with gentamicin). All the renal functioning parameters including; Blood urea nitrogen, Serum creatinine, Serum uric acid, Creatinine clearance, Serum electrolytes, Body weight, Urinary volume, Enzyme excretions, Urinary protein excretions and histological examination was performed for each and every group animals. The plant extract proved to have nephroprotective potentials may because of its known flavonoid contents and antioxidant properties.


Assuntos
Citrus , Rim/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Nitrogênio da Ureia Sanguínea , Citrus/química , Creatinina/sangue , Rim/patologia , Masculino , Estudos Prospectivos , Substâncias Protetoras/farmacologia , Coelhos
15.
Microsyst Nanoeng ; 10: 81, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38911343

RESUMO

Photodetectors (PDs) play a crucial role in imaging, sensing, communication systems, etc. Graphene (Gr), a leading two-dimensional material, has demonstrated significant potential for photodetection in recent years. However, its relatively weak interaction with light poses challenges for practical applications. The integration of silicon (Si) and perovskite quantum dots (PQDs) has opened new avenues for Gr in the realm of next-generation optoelectronics. This review provides a comprehensive investigation of Gr/Si Schottky junction PDs and Gr/PQD hybrid PDs as well as their heterostructures. The operating principles, design, fabrication, optimization strategies, and typical applications of these devices are studied and summarized. Through these discussions, we aim to illuminate the current challenges and offer insights into future directions in this rapidly evolving field.

16.
Pharmaceutics ; 16(2)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38399247

RESUMO

In the current study, matrices of losartan potassium were formulated with two different polymers (Ethocel 10 premium and Ethocel 10FP premium), along with a filler and a lubricant, at different drug-to-polymer w/w ratios (10:3, 10:4, and 10:5). The matrices were tested by the direct compression method, and their hardness, diameter, thickness, friability, weight variation, content uniformity, and in vitro dissolution tests were assessed to determine 24-h drug release rates. The matrices with Ethocel 10 FP at a 10:4 ratio exhibited pseudo-zero-order kinetics (n-value of 0.986), while the dissolution data of the test matrices and reference tablets did not match. The new test-optimized matrices were also tested in rabbits, and their pharmacokinetic parameters were investigated: half-life (11.78 ± 0.018 h), Tmax (2.105 ± 1.131 h), Cmax (205.98 ± 0.321 µg/mL), AUCo (5931.10 ± 1.232 µg·h/mL), AUCo-inf (7348.46 ± 0.234 µg·h/mL), MRTo-48h (17.34 ± 0.184 h), and Cl (0.002 ± 0.134 mL/min). A correlation value of 0.985 between the in vitro and in vivo results observed for the test-optimized matrices was observed, indicating a level-A correlation between the percentage of the drug released in vitro and the percentage of the drug absorbed in vivo. The matrices might improve patient compliance with once-a-day dosing and therapeutic outcomes.

17.
Acta Pol Pharm ; 70(3): 533-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23757944

RESUMO

Gentamicin is a potent antibiotic, effective against Gram negative bacteria. The most common adverse effect of gentamicin is nephrotoxicity. Present study was aimed to explore the protective potentials of Citrullus colocynthis against gentamicin induced nephrotoxicity due to its strong antioxidant properties. Toxic doses of gentamicin (80 mg/kg/day, i.m.) were administered alone and as co-therapy with the extract of C. colocynthis (25 mg/kg/day, p.o.). Physiological, biochemical and histological examinations were performed to compare the experimental and toxic groups (n = 6) with control group animals. Co-therapy of C. colocynthis with gentamicin protected changes in the body weight, blood urea nitrogen, creatinine clearance, proteins and lactate dehydrogenase excretions. However, a significant rise in serum creatinine and serum uric acid with fall in serum calcium and serum potassium was observed, which were significantly different from control group animals. Necrotic and ruptured tubules were also found abundantly. This study revealed that co-theapy of C. colocynthis with gentamicin for twenty one days, failed to protect renal injury associated by gentamicin in spite of its strong antioxidant properties.


Assuntos
Antioxidantes/farmacologia , Citrullus , Rim/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Creatinina/sangue , Gentamicinas/toxicidade , Rim/patologia , Masculino , Fitoterapia , Coelhos
18.
ACS Omega ; 8(33): 30221-30230, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37636925

RESUMO

Biogenic synthesis of silver nanoparticles (AgNPs) using plant extracts is gaining attention as a substitute to the conventional physical and chemical synthesis methods. This study reports a facile, cost-effective, and ecofriendly synthesis of AgNPs using leaf extract of Alnus nitida (A. nitida) and their antioxidant and antiproliferative activities. The biosynthesized AgNPs were characterized using various analytical techniques including UV-visible spectroscopy, energy-dispersive spectrometry, scanning electron microscopy (SEM), Fourier transform infrared (FTIR), X-ray diffraction (XRD), and dynamic light scattering. The antioxidant and cytotoxic potential of the extract and AgNPs was evaluated using different in vitro models. The UV-vis analysis revealed a surface plasmon resonance peak of 400 nm corresponding to the synthesis of AgNPs. SEM analysis confirmed the formation of heterogeneously dispersed particles of nano size, while the XRD and FTIR spectra confirmed the crystallinity and existence of different functional groups that helped in capping and stability of AgNPs. The antioxidant activity of AgNPs and extract, studied by 1,1-diphenyl 2-picryl hydrazyl (DPPH), fluorescence recovery after photobleaching (FRAP), 2, 2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), and H2O2 scavenging assays, showed a dose-dependent effect. The AgNPs at 1000 µg/mL significantly scavenged DPPH, FRAP, ABTS, and H2O2 by 66.45, 74.65, 78.81, and 72.56% with an average IC50 value of 33.31, 18.50, 16.46, and 15.65 µg/mL, respectively. The cytotoxic potential investigated by MTT assay revealed promising antiproliferative effects against different cancer cell lines. The IC50 values of AgNPs on MDA-MB-231, A549, and Hep-G2 cells were 14.88, 3.6, and 5.38 µg/mL, respectively. The results showed that AgNPs were more effective against lung and hepatocellular carcinoma. The selectivity index showed that AgNPs remained highly selective in retarding the growth of A549 and Hep-G2 cells as compared to normal cell lines HPAEpiC and HRPTEpiC. Overall, this study showed that biosynthesized AgNPs were associated with considerable antioxidant and cytotoxic effects. Our work suggests that A. nitida-mediated AgNPs should be evaluated further in order to develop safe and effective formulations for the treatment of different degenerative diseases.

19.
ACS Omega ; 8(37): 33955-33965, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37744808

RESUMO

This study aims to enhance the dissolution rate of a poorly water-soluble drug physcion by producing its nanoparticles (NPs) using an antisolvent precipitation with a syringe pump (APSP) method and to assess its antioxidant and cytotoxic potential. The NPs were prepared using a simple and cost-effective APSP method and subsequently characterized by different analytical techniques including dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray powder diffractometry (XRD). They were also subjected to solubility and dissolution studies, and different parameters such as dissolution efficiency (DE), mean dissolution time (MDT), and difference (f1) and similarity factors (f2) were determined. Furthermore, physcion and its NPs were investigated for antioxidant and cytotoxic effects using various in vitro assays. SEM and DLS analysis indicated that the average size of physcion NPs was 110 and 195 ± 5.6 nm, respectively. The average ζ-potential and polydispersibility index (PDI) of the prepared NPs were -22.5 mV and 0.18, respectively, showing excellent dispersibility. XRD confirmed the amorphous nature of physcion NPs. The solubility and dissolution rates of NPs were significantly higher than those of the original powder. The antioxidant potential studied by the (DPPH), FRAP, and H2O2 assays was greater for physcion NPs than that for the raw powder. The IC50 values of physcion NPs against the aforementioned models were 57.56, 22.30, and 22.68 µg/mL, respectively. Likewise, the cytotoxic potential investigated through the MTT assay showed that physcion NPs were more cytotoxic to cancer cell lines A549 (IC50 4.12 µg/mL), HepG2 (IC50 2.84 µg/mL), and MDA-MB-231 (IC50 2.97 µg/mL), while it had less effect on HPAEpiC (IC50 8.68 µg/mL) and HRPTEpiC (IC50 10.71 µg/mL) normal human epithelial cells. These findings have proved that the APSP method successfully produced physcion NPs with enhanced solubility, dissolution rate, and antioxidant and cytotoxic activities.

20.
Bull Environ Contam Toxicol ; 89(4): 816-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22864632

RESUMO

The estrogen pollution in the Tiaoxi River, which is the main source river for Taihu Lake, was investigated by chemical and bioassay analysis. Most estrogens species, except estrone, were not detected by the chemical analysis using liquid chromatography coupled with tandem mass spectrometry. The concentration of estrone in the samples ranged from ND (below the detection limit) to 17.25 ng/L. The estrogen activity in most water samples was also determined by the yeast estrogen screen. The 17ß-estradiol equivalent in the intake of Taihu Lake was 17.60 ng/L and was present in all water samples. This study demonstrates that combining chemical and bioassay analysis is an effective way to detect environmental contamination by estrogen species. Furthermore, the results indicate that the risk of estrogen contamination in the Tiaoxi River should not be ignored.


Assuntos
Monitoramento Ambiental/métodos , Estrogênios/análise , Rios/química , Poluentes Químicos da Água/análise , Bioensaio , Cromatografia Líquida , Espectrometria de Massas em Tandem , Poluição Química da Água/estatística & dados numéricos
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