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1.
Braz J Biol ; 84: e280570, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39109714

RESUMO

Anthocyanins are known as an antioxidant, and their water-soluble purple-colored pigments are very nutritive. Therefore, the present study investigated the antioxidant activity of black rice anthocyanins nano-composite against infertility induced by AlCl3 in rats. Anthocyanin silver nanoparticles (An-AgNPs) were prepared by reducing black rice anthocyanin with the metallic ions. Antioxidant activity (DPPH %) of anthocyanin was determined. Also, the morphology of (An-AgNPs) was examined by scanning electron microscopy (SEM). Albino rats were divided into five groups (negative control (NC): fed on basel diet, positive control (PC): treated with AlCl3 (34 mg/kg bw) for seventy days, and three other groups treated with AlCl3 (34 mg/kg bw) + An-AgNPs at 10, 15, and 20 mg/kg, b.w/ day, respectively for seventy days. Serum testosterone, LH, FSH, and estradiol were measured. Additionally, Sperm motility, Sperm count (Testicular and Epididymal), fructose in semen, and semen quality were determined. The values of the anthocyanin component and DPPH radical scavenging activity obtained were 3603.82±6.11 mg CCE/g and 84.62±1.98, respectively. An-AgNPs shows tend to agglomerate, particles are uniform in size and shape, and the diameter of the particles ranges between 70nm to 130nm. LH, estradiol and testosterone levels increased significantly in rats treated with An-AgNPs 10, 15, 20 mg/kg b.w+ AlCl3 (34 mg/kg bw) also exhibited significantly higher sperm motility, sperm count, and daily sperm production, and decreased sperm transit rate than G2. In comparison to G2, animals treated with AlCl3 (34 mg/kg bw) + An-AgNPs 10, 15, 20 mg/kg b.w(G3 to G5) had significantly higher semen and semen quality (P 0.05). We can conclude that the An-AgNPs showed a strong effect against infertility induced by AlCl3; this represents a suitable natural supply of biological substances for medicine and anthocyanins could be considered the ideal ingredients against oxidative stress-induced infertility.


Assuntos
Cloreto de Alumínio , Compostos de Alumínio , Antocianinas , Antioxidantes , Nanopartículas Metálicas , Oryza , Ratos Wistar , Prata , Animais , Antocianinas/farmacologia , Antocianinas/análise , Masculino , Antioxidantes/farmacologia , Oryza/química , Prata/química , Infertilidade Masculina , Cloretos , Motilidade dos Espermatozoides/efeitos dos fármacos , Nanocompostos/química , Microscopia Eletrônica de Varredura , Ratos , Testosterona/sangue , Contagem de Espermatozoides , Análise do Sêmen
2.
Nanotechnology ; 35(46)2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39116890

RESUMO

The translation of silver-based nanotechnology 'from bench to bedside' requires a deep understanding of the molecular aspects of its biological action, which remains controversial at low concentrations and non-spherical morphologies. Here, we present a hemocompatibility approach based on the effect of the distinctive electronic charge distribution in silver nanoparticles (nanosilver) on blood components. According to spectroscopic, volumetric, microscopic, dynamic light scattering measurements, pro-coagulant activity tests, and cellular inspection, we determine that at extremely low nanosilver concentrations (0.125-2.5µg ml-1), there is a relevant interaction effect on the serum albumin and red blood cells (RBCs). This explanation has its origin in the surface charge distribution of nanosilver particles and their electron-mediated energy transfer mechanism. Prism-shaped nanoparticles, with anisotropic charge distributions, act at the surface level, generating a compaction of the native protein molecule. In contrast, the spherical nanosilver particle, by exhibiting isotropic surface charge, generates a polar environment comparable to the solvent. Both morphologies induce aggregation at NPs/bovine serum albumin ≈ 0.044 molar ratio values without altering the coagulation cascade tests; however, the spherical-shaped nanosilver exerts a negative impact on RBCs. Overall, our results suggest that the electron distributions of nanosilver particles, even at extremely low concentrations, are a critical factor influencing the molecular structure of blood proteins' and RBCs' membranes. Isotropic forms of nanosilver should be considered with caution, as they are not always the least harmful.


Assuntos
Eritrócitos , Nanopartículas Metálicas , Soroalbumina Bovina , Prata , Prata/química , Nanopartículas Metálicas/química , Eritrócitos/metabolismo , Eritrócitos/química , Humanos , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , Propriedades de Superfície , Animais , Bovinos , Coagulação Sanguínea/efeitos dos fármacos , Proteínas Sanguíneas/metabolismo , Proteínas Sanguíneas/química , Teste de Materiais
3.
ACS Appl Bio Mater ; 7(8): 5530-5540, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39093994

RESUMO

This study reports on the modification of bacterial cellulose (BC) membranes produced by static fermentation of Komagataeibacter xylinus bacterial strains with graphene oxide-silver nanoparticles (GO-Ag) to yield skin wound dressings with improved antibacterial properties. The GO-Ag sheets were synthesized through chemical reduction with sodium citrate and were utilized to functionalize the BC membranes (BC/GO-Ag). The BC/GO-Ag composites were characterized to determine their surface charge, morphology, exudate absorption, antimicrobial activity, and cytotoxicity by using fibroblast cells. The antimicrobial activity of the wound dressings was assessed against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The results indicate that the BC/GO-Ag dressings can inhibit ∼70% of E. coli cells. Our findings also revealed that the porous BC/GO-Ag antimicrobial dressings can efficiently retain 94% of exudate absorption after exposure to simulated body fluid (SBF) for 24 h. These results suggest that the dressings could absorb excess exudate from the wound during clinical application, maintaining adequate moisture, and promoting the proliferation of epithelial cells. The BC/GO-Ag hybrid materials exhibited excellent mechanical flexibility and low cytotoxicity to fibroblast cells, making excellent wound dressings able to control bacterial infectious processes and promote the fast healing of dermal lesions.


Assuntos
Antibacterianos , Materiais Biocompatíveis , Celulose , Escherichia coli , Grafite , Teste de Materiais , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Prata , Staphylococcus aureus , Cicatrização , Grafite/química , Grafite/farmacologia , Prata/química , Prata/farmacologia , Cicatrização/efeitos dos fármacos , Celulose/química , Celulose/farmacologia , Nanopartículas Metálicas/química , Antibacterianos/química , Antibacterianos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Tamanho da Partícula , Pseudomonas aeruginosa/efeitos dos fármacos , Gluconacetobacter xylinus/química , Humanos , Camundongos , Bandagens , Animais
4.
Int J Mol Sci ; 25(15)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39126001

RESUMO

Breast cancer is the most diagnosed type of cancer worldwide and the second cause of death in women. Triple-negative breast cancer (TNBC) is the most aggressive, and due to the lack of specific targets, it is considered the most challenging subtype to treat and the subtype with the worst prognosis. The present study aims to determine the antitumor effect of beta-D-glucose-reduced silver nanoparticles (AgNPs-G) in a murine model of TNBC, as well as to study its effect on the tumor microenvironment. In an airbag model with 4T1 tumor cell implantation, the administration of AgNPs-G or doxorubicin showed antitumoral activity. Using immunohistochemistry it was demonstrated that treatment with AgNPs-G decreased the expression of PCNA, IDO, and GAL-3 and increased the expression of Caspase-3. In the tumor microenvironment, the treatment increased the percentage of memory T cells and innate effector cells and decreased CD4+ cells and regulatory T cells. There was also an increase in the levels of TNF-α, IFN-γ, and IL-6, while TNF-α was increased in serum. In conclusion, we suggest that AgNPs-G treatment has an antitumor effect that is demonstrated by its ability to remodel the tumor microenvironment in mice with TNBC.


Assuntos
Glucose , Nanopartículas Metálicas , Prata , Neoplasias de Mama Triplo Negativas , Microambiente Tumoral , Animais , Microambiente Tumoral/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Prata/química , Nanopartículas Metálicas/química , Feminino , Camundongos , Glucose/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Camundongos Endogâmicos BALB C , Doxorrubicina/farmacologia , Humanos
5.
Sensors (Basel) ; 24(15)2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39124094

RESUMO

Graphene-based surface plasmon resonance (SPR) biosensors have emerged as a promising technology for the highly sensitive and accurate detection of biomolecules. This study presents a comprehensive theoretical analysis of graphene-based SPR biosensors, focusing on configurations with single and bimetallic metallic layers. In this study, we investigated the impact of various metallic substrates, including gold and silver, and the number of graphene layers on key performance metrics: sensitivity of detection, detection accuracy, and quality factor. Our findings reveal that configurations with graphene first supported on gold exhibit superior performance, with sensitivity of detection enhancements up to 30% for ten graphene layers. In contrast, silver-supported configurations, while demonstrating high sensitivity, face challenges in maintaining detection accuracy. Additionally, reducing the thickness of metallic layers by 30% optimizes light coupling and enhances sensor performance. These insights highlight the significant potential of graphene-based SPR biosensors in achieving high sensitivity of detection and reliability, paving the way for their application in diverse biosensing technologies. Our findings pretend to motivate future research focusing on optimizing metallic layer thickness, improving the stability of silver-supported configurations, and experimentally validating the theoretical findings to further advance the development of high-performance SPR biosensors.


Assuntos
Técnicas Biossensoriais , Ouro , Grafite , Prata , Ressonância de Plasmônio de Superfície , Grafite/química , Ressonância de Plasmônio de Superfície/métodos , Prata/química , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Ouro/química
6.
Pharmacol Rep ; 76(5): 1147-1159, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39150661

RESUMO

BACKGROUND: Currently, there is no antiviral licensed to treat chikungunya fever, a disease caused by the infection with Alphavirus chikungunya (CHIKV). Treatment is based on analgesic and anti-inflammatory drugs to relieve symptoms. Our study aimed to evaluate the antiviral activity of sulfadoxine (SFX), an FDA-approved drug, and its derivatives complexed with silver(I) (AgSFX), salicylaldehyde Schiff base (SFX-SL), and with both Ag and SL (AgSFX-SL) against CHIKV. METHODS: The anti-CHIKV activity of SFX and its derivatives was investigated using BHK-21 cells infected with CHIKV-nanoluc, a marker virus-carrying nanoluciferase reporter. Dose-response and time of drug-addition assays were performed in order to assess the antiviral effects of the compounds, as well as in silico data and ATR-FTIR analysis for insights on their mechanisms of action. RESULTS: The SFX inhibited 34% of CHIKV replication, while AgSFX, SFX-SL, and AgSFX-SL enhanced anti-CHIKV activity to 84%, 89%, and 95%, respectively. AgSFX, SFX-SL, and AgSFX-SL significantly decreased viral entry and post-entry to host cells, and the latter also protected cells against infection. Additionally, molecular docking calculations and ATR-FTIR analysis demonstrated interactions of SFX-SL, AgSFX, and AgSFX-SL with CHIKV. CONCLUSIONS: Collectively, our findings suggest that the addition of metal ions and/or Schiff base to SFX improved its antiviral activity against CHIKV.


Assuntos
Antivirais , Febre de Chikungunya , Vírus Chikungunya , Sulfadoxina , Vírus Chikungunya/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/química , Animais , Linhagem Celular , Sulfadoxina/farmacologia , Febre de Chikungunya/tratamento farmacológico , Febre de Chikungunya/virologia , Cricetinae , Bases de Schiff/farmacologia , Prata/farmacologia , Prata/química , Replicação Viral/efeitos dos fármacos , Simulação de Acoplamento Molecular , Relação Dose-Resposta a Droga , Humanos , Aldeídos
7.
J Mater Chem B ; 12(36): 8993-9004, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39145426

RESUMO

Among external stimuli-responsive therapy approaches, those using near infrared (NIR) light irradiation have attracted significant attention to treat bone-related diseases and bone tissue regeneration. Therefore, the development of metallic biomaterials sensitive to NIR stimuli is an important area of research in orthopaedics. In this study, we have generated in situ prism-shaped silver nanoparticles (p-AgNPs) in a biomorphic nano-holed TiO2 coating on a Ti6Al4V alloy (a-Ti6Al4V). Insertion of p-AgNPs does not disturb the periodically arranged sub-wavelength-sized unit cell on the a-Ti6Al4V dielectric structure, while they exacerbate its peculiar optical response, which results in a higher NIR reflectivity and high efficiency of NIR photothermal energy conversion suitable to bacterial annihilation. Together, these results open a promising path toward strategic bone therapeutic procedures, providing novel insights into precision medicine.


Assuntos
Ligas , Antibacterianos , Raios Infravermelhos , Nanopartículas Metálicas , Prata , Propriedades de Superfície , Titânio , Titânio/química , Titânio/farmacologia , Ligas/química , Ligas/farmacologia , Prata/química , Prata/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Nanopartículas Metálicas/química , Staphylococcus aureus/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Escherichia coli/efeitos dos fármacos , Tamanho da Partícula
8.
Biomolecules ; 14(7)2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39062496

RESUMO

In this work, the hexane, chloroform, and methanol extracts from Kalanchoe fedtschenkoi were utilized to green-synthesize silver nanoparticles (Kf1-, Kf2-, and Kf3-AgNPs). The Kf1-, Kf2-, and Kf3-AgNPs were characterized by spectroscopy and microscopy techniques. The antibacterial activity of AgNPs was studied against bacteria strains, utilizing the microdilution assay. The DPPH and H2O2 assays were considered to assess the antioxidant activity of AgNPs. The results revealed that Kf1-, Kf2-, and Kf3-AgNPs exhibit an average diameter of 39.9, 111, and 42 nm, respectively. The calculated ζ-potential of Kf1-, Kf2-, and Kf3-AgNPs were -20.5, -10.6, and -7.9 mV, respectively. The UV-vis analysis of the three samples demonstrated characteristic absorption bands within the range of 350-450 nm, which confirmed the formation of AgNPs. The FTIR analysis of AgNPs exhibited a series of bands from 3500 to 750 cm-1, related to the presence of extracts on their surfaces. SEM observations unveiled that Kf1- and Kf2-AgNPs adopted structural arrangements related to nano-popcorns and nanoflowers, whereas Kf3-AgNPs were spherical in shape. It was determined that treatment with Kf1-, Kf2-, and Kf3-AgNPs was demonstrated to inhibit the growth of E. coli, S. aureus, and P. aeruginosa in a dose-dependent manner (50-300 µg/mL). Within the same range, treatment with Kf1-, Kf2-, and Kf3-AgNPs decreased the generation of DPPH (IC50 57.02-2.09 µg/mL) and H2O2 (IC50 3.15-3.45 µg/mL) radicals. This study highlights the importance of using inorganic nanomaterials to improve the biological performance of plant extracts as an efficient nanotechnological approach.


Assuntos
Antibacterianos , Antioxidantes , Química Verde , Kalanchoe , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Extratos Vegetais , Prata , Nanopartículas Metálicas/química , Prata/química , Prata/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Kalanchoe/química , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/síntese química , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química , Picratos/antagonistas & inibidores , Picratos/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Peróxido de Hidrogênio
9.
Braz J Microbiol ; 55(3): 2789-2796, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39023813

RESUMO

Acinetobacter baumannii is a bacteria associated with nosocomial infections and outbreaks, difficult to control due to its antibiotic resistance, ability to survive in adverse conditions, and biofilm formation adhering to biotic and abiotic surfaces. Therefore, this study aimed to evaluate the antibiofilm activity of biogenic silver nanoparticle (Bio-AgNP) and polymyxin B alone and combined in biofilms formed by isolates of carbapenem-resistant A. baumannii (CR-Ab). In the biofilm formation inhibition assay, CR-Ab strains were exposed to different concentrations of the treatments before inducing biofilm formation, to determine the ability to inhibit/prevent bacterial biofilm formation. While in the biofilm rupture assay, the bacterial biofilm formation step was previously carried out and the adhered cells were exposed to different concentrations of the treatments to evaluate their ability to destroy the bacterial biofilm formed. All CR-Ab isolates and ATCC® 19606™ used in this study are strong biofilm formers. The antibiofilm activity of Bio-AgNP and polymyxin B against CR-Ab and ATCC® 19606™ demonstrated inhibitory and biofilm-disrupting activity. When used in combination, Bio-AgNP and polymyxin B inhibited 4.9-100% of biofilm formation in the CR-Ab isolates and ATCC® 19606™. Meanwhile, when Bio-AgNP and polymyxin B were combined, disruption of 6.8-77.8% of biofilm formed was observed. Thus, antibiofilm activity against CR-Ab was demonstrated when Bio-AgNP was used alone or in combination with polymyxin B, emerging as an alternative in the control of CR-Ab strains.


Assuntos
Acinetobacter baumannii , Antibacterianos , Biofilmes , Carbapenêmicos , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Polimixina B , Prata , Biofilmes/efeitos dos fármacos , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/fisiologia , Polimixina B/farmacologia , Prata/farmacologia , Prata/química , Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Carbapenêmicos/farmacologia , Infecções por Acinetobacter/microbiologia , Infecções por Acinetobacter/tratamento farmacológico , Humanos , Sinergismo Farmacológico , Farmacorresistência Bacteriana
10.
Ecotoxicology ; 33(7): 683-696, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38861073

RESUMO

Silver nanoparticles (AgNPs) are among the most produced nanomaterials in the world and are incorporated into several products due to their biocide and physicochemical properties. Since freshwater bodies are AgNPs main final sink, several consequences for biota are expected to occur. With the hypothesis that AgNPs can interact with environmental factors, we analyzed their ecotoxicity in combination with humic acids and algae. In addition to the specific AgNPs behavior in the media, we analyzed the mortality, growth, and phototactic behavior of Chydorus eurynotus (Cladocera) as response variables. While algae promoted Ag+ release, humic acids reduced it by adsorption, and their combination resulted in an intermediated Ag+ release. AgNPs affected C. eurynotus survival and growth, but algae and humic acids reduced AgNPs lethality, especially when combined. The humic acids mitigated AgNP effects in C. eurynotus growth, and both factors improved its phototactic behavior. It is essential to deepen the study of the isolated and combined influences of environmental factors on the ecotoxicity of nanoparticles to achieve accurate predictions under realistic exposure scenarios.


Assuntos
Cladocera , Substâncias Húmicas , Nanopartículas Metálicas , Prata , Poluentes Químicos da Água , Prata/toxicidade , Nanopartículas Metálicas/toxicidade , Animais , Poluentes Químicos da Água/toxicidade , Cladocera/efeitos dos fármacos , Cladocera/fisiologia
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