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1.
J Environ Sci (China) ; 148: 437-450, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095178

RESUMO

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.


Assuntos
Nanocompostos , Fotólise , Prata , Poluentes Químicos da Água , Purificação da Água , Nanocompostos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Prata/química , Catálise , Nitrilas/química , Compostos de Nitrogênio/química , Adsorção , Grafite
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124991, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39163773

RESUMO

The contamination of mycotoxins poses a serious threat to global food security, hence the urgent need for simultaneous detection of multiple mycotoxins. Herein, two SERS nanoprobes were synthesized by embedded SERS tags (4-mercaptopyridine, 4MPy; 4-mercaptobenzonitrile, TBN) into the Au and Ag core-shell structure, and each was coupled with the aptamers specific to ochratoxin A (OTA) and zearalenone (ZEN). Meanwhile, a rigid enhanced substrate Indium tin oxide glass/AuNPs/Graphene oxide (ITO/AuNPs/GO) was combined with aptamer functionalized Au@AgNPs via π-π stacking interactions between the aptamer and GO to construct a surface-enhanced Raman spectroscopy (SERS) aptasensor, thereby inducing a SERS enhancement effect for the effective and swift simultaneous detection of both OTA and ZEN. The presence of OTA and ZEN caused signal probes dissociation, resulting in an inverse correlation between Raman signal intensity (1005 cm-1 and 2227 cm-1) and the concentrations of OTA and ZEN, respectively. The SERS aptasensor exhibited wide linear detection ranges of 0.001-20 ng/mL for OTA and 0.1-100 ng/mL for ZEN, with low detection limits (LOD) of 0.94 pg/mL for OTA and 59 pg/mL for ZEN. Furthermore, the developed SERS aptasensor demonstrated feasible applicability in the detection of OTA and ZEN in maize, showcasing its substantial potential for practical implementation.


Assuntos
Aptâmeros de Nucleotídeos , Ouro , Grafite , Limite de Detecção , Nanopartículas Metálicas , Ocratoxinas , Prata , Análise Espectral Raman , Zearalenona , Ocratoxinas/análise , Análise Espectral Raman/métodos , Ouro/química , Zearalenona/análise , Nanopartículas Metálicas/química , Aptâmeros de Nucleotídeos/química , Prata/química , Grafite/química , Compostos de Estanho/química , Técnicas Biossensoriais/métodos , Contaminação de Alimentos/análise
3.
Biomaterials ; 313: 122772, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39190942

RESUMO

Implant-associated infection (IAI) has become an intractable challenge in clinic. The healing of IAI is a complex physiological process involving a series of spatiotemporal connected events. However, existing titanium-based implants in clinic suffer from poor antibacterial effect and single function. Herein, a versatile surface platform based on the presentation of sequential function is developed. Fabrication of titania nanotubes and poly-γ-glutamic acid (γ-PGA) achieves the efficient incorporation of silver ions (Ag+) and the pH-sensitive release in response to acidic bone infection microenvironment. The optimized PGA/Ag platform exhibits satisfactory biocompatibility and converts macrophages from pro-inflammatory M1 to pro-healing M2 phenotype during the subsequent healing stage, which creates a beneficial osteoimmune microenvironment and promotes angio/osteogenesis. Furthermore, the PGA/Ag platform mediates osteoblast/osteoclast coupling through inhibiting CCL3/CCR1 signaling. These biological effects synergistically improve osseointegration under bacterial infection in vivo, matching the healing process of IAI. Overall, the novel integrated PGA/Ag surface platform proposed in this study fulfills function cascades under pathological state and shows great potential in IAI therapy.


Assuntos
Antibacterianos , Ácido Poliglutâmico , Prata , Titânio , Animais , Titânio/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Camundongos , Ácido Poliglutâmico/química , Ácido Poliglutâmico/análogos & derivados , Prata/química , Prata/farmacologia , Propriedades de Superfície , Nanotubos/química , Células RAW 264.7 , Infecções Relacionadas à Prótese/tratamento farmacológico , Osseointegração/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Cicatrização/efeitos dos fármacos , Próteses e Implantes
4.
Biomaterials ; 312: 122721, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39106817

RESUMO

Silver nanoparticles (AgNPs) are a potential antiviral agent due to their ability to disrupt the viral particle or alter the virus metabolism inside the host cell. In vitro, AgNPs exhibit antiviral activity against the most common human respiratory viruses. However, their capacity to modulate immune responses during respiratory viral infections has yet to be explored. This study demonstrates that administering AgNPs directly into the lungs prior to infection can reduce viral loads and therefore virus-induced cytokines in mice infected with influenza virus or murine pneumonia virus. The prophylactic effect was diminished in mice with depleted lymphoid cells. We showed that AgNPs-treatment resulted in the recruitment and activation of lymphocytes in the lungs, particularly natural killer (NK) cells. Mechanistically, AgNPs enhanced the ability of alveolar macrophages to promote both NK cell migration and IFN-γ production. By contrast, following infection, in mice treated with AgNPs, NK cells exhibited decreased activation, indicating that these nanoparticles can regulate the potentially deleterious activation of these cells. Overall, the data suggest that AgNPs may possess prophylactic antiviral properties by recruiting and controlling the activation of lymphoid cells through interaction with alveolar macrophages.


Assuntos
Células Matadoras Naturais , Pulmão , Nanopartículas Metálicas , Infecções por Orthomyxoviridae , Prata , Animais , Prata/química , Prata/farmacologia , Nanopartículas Metálicas/química , Pulmão/virologia , Pulmão/patologia , Pulmão/efeitos dos fármacos , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/virologia , Camundongos , Células Matadoras Naturais/efeitos dos fármacos , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/virologia , Camundongos Endogâmicos C57BL , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Antivirais/farmacologia , Antivirais/uso terapêutico , Feminino , Ativação Linfocitária/efeitos dos fármacos
5.
Luminescence ; 39(9): e4894, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39258511

RESUMO

In this study, biological synthesis of silver nanoparticles (AgNPs) using Senna auriculata flower extract for antibacterial activities was reported. The silver spectra compared to the plant extract show a rightward shift in AgNP peaks, indicating successful nanoparticle formation. The absorption band at 302 nm and the disappearance or shift of other peaks further confirm the synthesis. X-ray diffraction (XRD) analysis reveals that the AgNPs synthesized with S. auriculata extract have an average crystallite size of 25 nm. Transmission electron microscopy (TEM) results exhibited a polydispersed, spherical shape with sizes ranging from 70 nm, in clear contrast to the electron microscope image that showed their spherical shape. When examining the selected area electron diffraction (SAED) image, a specific set of lattice planes was correlated with a specific spot. A histogram of AgNP particle size distribution can be seen. AgNPs were tested against four different strains of bacteria for their antibacterial effectiveness, including gram negative bacteria (Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus), as well as gram positive bacteria (S. aureus, d. Bacillus subtilis), at various concentrations of AgNP. The results of in vitro experiments indicate that AgNPs containing S. auriculata flowers inhibit amylase well. At two concentrations, ~16.03% and ~70.99%, AgNPs inhibit the reaction at low and high concentrations, respectively.


Assuntos
Antibacterianos , Flores , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Extratos Vegetais , Prata , Prata/química , Prata/farmacologia , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Flores/química , Tamanho da Partícula , Difração de Raios X
6.
Sci Rep ; 14(1): 21763, 2024 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-39294193

RESUMO

Metal and metal oxide nanocomposites have unique properties and are promising for antibacterial and anticancer applications. In this work, we aimed to highlight the relationship between the biosynthesis ways of silver and gold-doped zinc oxide nanocomposites and their functions as anticancer on cell lines (MCF-7 and HepG2). The propolis was used to biosynthesize four different nanoparticles with the same components, including zinc, gold and silver. The nanocomposites were characterized using various techniques, including ultraviolet-visible spectroscopy (UV-Vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Energy Dispersive X-ray analysis (EDX) and cytotoxicity assays. The result of this study showed that formed nanocomposites have a similar level of Zn, Au, and Ag, ranging from 23-34%, 2-6%, and 2-3%, respectively. In addition, adding the components simultaneously produces the fastest color change, and the fabricated nanoparticles have spherical shapes with different layers. In addition, the prepared nanoparticles influenced the cell viability of the cancer cell lines, with the most effective one when Zn, Au, and Ag were added spontaneously to form a nanocomposite called (All) with IC50 of 24.5 µg/mL for MCF7 cells and 29.1 µg/mL for HepG2 cells. Thus, the study illustrates that the preparation of nanocomposite generated through green synthesis with different methods significantly affects the structure and function and may improve the synthesis of nanocomposite to be developed into an efficacious therapeutic agent for cancers. In addition, this study opens the door toward a novel track in the field of nanocomposites as it links the synthesis with structure and function. Further anti-cancer properties, as well as animal testing are needed for those nanocomposites.


Assuntos
Antineoplásicos , Ouro , Química Verde , Nanocompostos , Própole , Prata , Óxido de Zinco , Humanos , Própole/química , Própole/farmacologia , Ouro/química , Nanocompostos/química , Prata/química , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Células Hep G2 , Células MCF-7 , Nanopartículas Metálicas/química , Sobrevivência Celular/efeitos dos fármacos
7.
Luminescence ; 39(9): e4891, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39229976

RESUMO

Lepidagathis cristata (L. cristata) plant produces reducing and capping agents; this study utilized microwave-assisted biogenic synthesis to manufacture silver nanoparticles (AgNPs) using this plant. The structure, morphology, and crystallinity phases of prepared nanoparticles (NPs) were characterized by ultraviolet-visible spectroscopy (UV-viz), powder X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). Biologically synthesized AgNPs were treated against pathogenic bacteria species including Escherichia coli (E. coli), Bacillus subtilis (B. subtilis), and Staphylococcus aureus (S. aureus) and its highest zone of inhibition 10 ± 1.45 mm, 10 ± 0.74 mm, and 6 ± 0.43 mm, respectively, at the concentration of 100 µg/mL. The cytotoxic activity of AgNPs against MCF-7 breast cancer cells revealed significant growth inhibition by inhibiting cell viability, inhibitory concentration of 50% (IC50) of NPs observed at 55.76 µg/mL concentration. Finally, our findings concluded that the L. cristata-mediated biosynthesized AgNPs proved its potential antibacterial and neoplastic properties against MCF cells by endorsing the inhibition of cell proliferation especially with low concentration.


Assuntos
Antibacterianos , Ensaios de Seleção de Medicamentos Antitumorais , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Extratos Vegetais , Prata , Prata/química , Prata/farmacologia , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Humanos , Células MCF-7 , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Bacillus subtilis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/síntese química , Água/química , Relação Dose-Resposta a Droga , Feminino
8.
Georgian Med News ; (351): 102-108, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39230231

RESUMO

BACKGROUND: Control of rifampicin-resistant tuberculosis (RR-MTB) requires novel technologies for restoring the anti-TB efficacy of priority drugs. We sought to evaluate the ability of nanotechnology application in the recovery of the anti-tuberculosis efficacy of rifampicin. METHODS: Nanocomposite- standard dose of rifampicin and 20 nm silver nanoparticles (AgNPs) suspension solution of 6 different concentrations: 0.25%; 0.5%; 1%; 2.5%; 5%; and 10%, were supplemented to 70 rifampicin-resistant mycobacterium tuberculosis (RR-MTB) isolates. The control arm consisted of 35 RR-MTB isolates and AgNPs suspension with identical concentrations. The inhibitory effect of nanocomposites was evaluated by MTB growth rate using the BACTECTM MGIT 960TM. The safety assessment of single-use AgNPs was conducted in experimental animals. RESULTS: The suppression process of AgNPs on RR-MTB isolates started with 2,5% nanocomposite solution application and full suppression was achieved in 5% and 10% nanocomposite solutions. A standard dose of rifampicin and a 2.5% solution of AgNPs increased the minimal inhibitory effect on RR-MTB by 10% (total 80%) vs the isolated use of a 2.5% solution of AgNPs (70%). An experiment on animals revealed the complete safety of a single injection of ultra-high doses of AgNPs. CONCLUSION: The study showed the potentiating effect of AgNPs in overcoming the resistance of MTB to rifampicin providing a scientific basis for further research.


Assuntos
Nanopartículas Metálicas , Mycobacterium tuberculosis , Nanocompostos , Rifampina , Prata , Rifampina/farmacologia , Prata/química , Prata/farmacologia , Nanocompostos/química , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/crescimento & desenvolvimento , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Animais , Humanos , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Antituberculosos/farmacologia , Antibióticos Antituberculose/farmacologia
9.
J Biomed Mater Res B Appl Biomater ; 112(9): e35461, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39225464

RESUMO

In laboratory conditions, composite sutures based on polylactide (PLA) containing chitin nanofibrils modified with polyethylene glycol (CN-PEG) and poviargol (silver nanoparticles stabilized with poly(N-vinylpyrrolidone)) were obtained, studied, and used as a prototype. Surgical sutures threads with the addition of CN-PEG have stable mechanical properties both in air and in a buffer simulating the environment of a living organism. The yield strength of oriented threads decreased by an average of 15%, whereas for non-oriented threads the decrease was 3-4 times. The strength values in simple units of unfilled PLA, PLA containing 5 wt % CN-PEG, and PLA with 1 wt % Poviargol were on average 50% higher than the national standard 31620-2012. The results of in vivo experiments on albino rats (cross-linking skin and muscle tissue in the linea alba area) showed that composite sutures are best for suturing muscle tissue, whereas unfilled PLA sutures are more suitable for suturing skin. When suturing muscle tissue, suturing with composite sutures increased the number of collagen fibers of different diameters.


Assuntos
Poliésteres , Suturas , Cicatrização , Animais , Poliésteres/química , Ratos , Cicatrização/efeitos dos fármacos , Teste de Materiais , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Ferida Cirúrgica/patologia , Ferida Cirúrgica/terapia , Masculino , Prata/química , Prata/farmacologia , Quitina/química , Quitina/farmacologia
10.
Mikrochim Acta ; 191(10): 612, 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39305299

RESUMO

An innovative method is introduced based on the combination of label-free surface-enhanced Raman scattering with advanced multivariate analysis. This technique allows both quantitative and qualitative assessment of Salmonella typhimurium and Escherichia coli on eggshells. Using silver nanocubes embedded in polydimethylsiloxane, we consistently achieved Raman spectra of bacteria. The stability of the Ag NCs@PDMS substrate is confirmed using rhodamine 6G over 30 days under standard conditions. Principal component analysis (PCA) effectively distinguishes between S. typhimurium and E. coli spectra. Partial least squares regression (PLS) models were developed for quantitative determination of bacteria on egg surfaces, yielding accurate results with minimal error. The S. typhimurium model achieves Rc2 = 0.9563 and RMSEC = 0.601 in calibration, and Rv2 = 0.9113 and RMSEV = 0.907 in validation. Similarly, the E. coli model achieves Rc2 = 0.9877 and RMSEC = 0.322 in calibration, and Rv2 = 0.9606 and RMSEV = 0.579 in validation. Recoveries validate PLS predictions by inoculating egg surfaces with varying bacterial amounts. Our study demonstrates the feasibility of SERS-PLS for quantitative determination of S. typhimurium and E. coli on eggshells, promising enhanced food safety protocols.


Assuntos
Dimetilpolisiloxanos , Ovos , Escherichia coli , Nanopartículas Metálicas , Salmonella typhimurium , Prata , Análise Espectral Raman , Análise Espectral Raman/métodos , Prata/química , Salmonella typhimurium/isolamento & purificação , Escherichia coli/isolamento & purificação , Nanopartículas Metálicas/química , Dimetilpolisiloxanos/química , Ovos/microbiologia , Animais , Microbiologia de Alimentos/métodos , Casca de Ovo/microbiologia , Casca de Ovo/química , Análise de Componente Principal , Contaminação de Alimentos/análise
11.
Bull Environ Contam Toxicol ; 113(4): 42, 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39306638

RESUMO

In the present paper, the assessment of vortex-assisted dispersive magnetic solid-phase extraction using amino-functionalized mesoporous combined with direct magnetic sorbent sampling (DMSS) in flame or furnace atomic absorption spectrometry (FAAS or FF-AAS) was demonstrated for highly sensitive silver determination in water samples. The developed method showed significant enrichment factors compared to conventional pneumatic nebulization by FAAS, 607 for DMSS-FF-AAS and 114 for DMSS-FAAS. The analytical curve showed linearity in the range from 5.0 to 70.0 µg L- 1 and 1.0 to 15.0 µg L- 1 and limits of detection of 0.59 and 0.09 µg L- 1 for DMSS-FAAS and DMSS-FF-AAS, respectively. The intra and inter-day precision evaluated as a percentage of the relative standard deviation (RSD,%) ranged from 1.89 to 4.71% for levels of 25.0 and 65.0 µg L- 1. The method was applied in different kinds of water samples without matrix effects, yielding recovery values from 90 to 110%.


Assuntos
Prata , Extração em Fase Sólida , Espectrofotometria Atômica , Poluentes Químicos da Água , Extração em Fase Sólida/métodos , Prata/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Limite de Detecção
12.
Sci Rep ; 14(1): 21753, 2024 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-39294225

RESUMO

The aim of presented study was to test nutritional properties of potato tubers and silver ions accumulation pattern after foliar application of silver nanoparticles (AgNPs) during potato vegetation. Potato plants were sprayed with different concentration of Ag nanoparticles (0.1, 1.0 and 10 mg·dm-3) synthesized with incorporation with sodium dodecyl sulphate (SDS) and sodium citrate as stabilizing agent. The lowest amounts of silver ions were transported to the tubers after spraying with AgNPs synthesized with SDS, rather than with citrate. Nevertheless silver ions accumulation in tubers was negligible. SDS method of synthesis was more favourable in terms of nutritional properties of potato tubers. The highest tested concentration of AgNPs_SDS had a favourable effect on a variety of macro- and micronutrients, ascorbic acid and soluble sugars. In turn, lower concentrations of AgNPs_SDS increased the content of phenolic compounds and free radical scavenging efficiency of tubers. These correlations were also confirmed by Principal Component Analysis.


Assuntos
Nanopartículas Metálicas , Tubérculos , Prata , Solanum tuberosum , Solanum tuberosum/metabolismo , Solanum tuberosum/química , Nanopartículas Metálicas/química , Prata/química , Tubérculos/química , Tubérculos/metabolismo , Ácido Ascórbico/metabolismo , Ácido Ascórbico/análise , Antioxidantes , Dodecilsulfato de Sódio/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Fenóis/análise
13.
Int J Nanomedicine ; 19: 9009-9033, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39246425

RESUMO

Background: The high infectivity of coronaviruses has led to increased interest in developing new strategies to prevent virus spread. Silver nanoparticles (AgNPs) and graphene oxide (GO) have attracted much attention in the antiviral field. We investigated the potential antiviral activity of GO and AgNPs combined in the nanocomposite GO-Ag against murine betacoronavirus MHV using an in vitro model. Methods: GO, AgNPs, and GO-Ag characterization (size distribution, zeta potential, TEM visualization, FT-IR, and EDX analysis) and XTT assay were performed. The antiviral activity of GO-Ag nanocomposites was evaluated by RT-qPCR and TCID50 assays. The results were compared with free AgNPs and pure GO. Cell growth and morphology of MHV-infected hepatocytes treated with GO-Ag composites were analyzed by JuLI™Br. Immunofluorescence was used to visualize the cell receptor used by MHV. Ultrastructural SEM analysis was performed to examine cell morphology after MHV infection and GO-Ag composite treatment. Results: A significant reduction in virus titer was observed for all nanocomposites tested, ranging from 3.2 to 7.3 log10 TCID50. The highest titer reduction was obtained for GO 5 µg/mL - Ag 25 µg/mL in the post-treatment method. These results were confirmed by RT-qPCR analysis. The results indicate that GO-Ag nanocomposites exhibited better antiviral activity compared to AgNPs and GO. Moreover, the attachment of AgNPs to the GO flake platform reduced their cytotoxicity. In addition, the GO-Ag composite modulates the distribution of the Ceacam1 cell receptor and can modulate cell morphology. Conclusion: Graphene oxide sheets act as a stabilizing agent, inhibiting the accumulation of AgNPs and reducing their cellular toxicity. The GO-Ag composite can physically bind and inhibit murine betacoronavirus from entering cells. Furthermore, the constant presence of GO-Ag can inhibit MHV replication and significantly limit its extracellular release. In conclusion, GO-Ag shows promise as an antiviral coating on solid surfaces to minimize virus transmission and spread.


Assuntos
Antivirais , Grafite , Nanopartículas Metálicas , Nanocompostos , Prata , Grafite/farmacologia , Grafite/química , Prata/química , Prata/farmacologia , Animais , Nanocompostos/química , Antivirais/farmacologia , Antivirais/química , Camundongos , Nanopartículas Metálicas/química , Vírus da Hepatite Murina/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/virologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Linhagem Celular
14.
J Inorg Biochem ; 261: 112719, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39236445

RESUMO

Herein, a series of new Ag(I)-NHC complexes containing 1,3-dioxane group were synthesized by the direct reaction of Ag2O and benzimidazolium salts in light-free conditions. All Ag(I)-NHC complexes were spectrally characterized using 1H, 13C NMR, FT-IR, LC-MS, and elemental analysis. Additionally, the structures of compounds 1a and 1e were elucidated by the single X-ray diffraction techniques. Further, the synthesized Ag(I)-NHC complexes were evaluated for cytotoxicity study on the L-929 cells and the anticancer activity against the HCT 116 and MCF-7 cancer cell lines. Notably, 1a showed significant anticancer activity against HCT 116 with an IC50 of 6.37 ± 0.92 µg/mL compared to cisplatin (IC50 = 36.75 ± 1.76 µg/mL). 1c (IC50 = 3.21 ± 1.96 µg/mL) and 1e (IC50 = 3.72 ± 1.12 µg/mL) exhibited significant anticancer activity against MCF-7 cells and was similar to cisplatin (IC50 = 32.17 ± 2.85 µg/mL). Meanwhile, 1a and 1e displayed the highest selectivity index. Most importantly, the cell viability test showed that 1e induced neglectable cytotoxicity (IC50 = 36.38 ± 2.27 µg/mL) toward L-929 and was similar to cisplatin (IC50 = 36.11 ± 2.09 µg/mL). The anticancer activities of Ag(I)-NHC complexes vary depending on the substituent group of the silver complex and the cell line type. Moreover, the inhibitory mechanism of 1e was not dependent on caspase-associated apoptosis initiated by the lysosomal-mitochondrial pathway. Taken together, we conclude that this work provides a simple and rapid protocol for the synthesis of Ag(I)-NHC complexes and the featured Ag(I)-NHC complexes have an anticancer drug potential for biomedical applications.


Assuntos
Antineoplásicos , Complexos de Coordenação , Dioxanos , Prata , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Prata/química , Prata/farmacologia , Dioxanos/química , Dioxanos/farmacologia , Complexos de Coordenação/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Células MCF-7 , Ligantes , Apoptose/efeitos dos fármacos , Células HCT116 , Linhagem Celular Tumoral , Camundongos , Animais , Desenho de Fármacos
15.
Sci Rep ; 14(1): 20744, 2024 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-39251604

RESUMO

Silver nanoparticles (AgNPs) have been successfully synthesized using leaf extract of Neem (Azadirachta Indica), Mint (Mentha Piperita), Tulsi (Ocimum Tenuiflorum), Bermuda grass (Cynodon Dactylon) and silver salt. As plant extracts produce best capping material for the stabilization of nanoparticles. AgNPs were characterized by UV-Vis spectroscopy in range of 200-800 nm and transmission electron microscopy TEM, XRD and FTIR. The nanoparticles synthesized were mainly in sizes between 25 and 100 nm. They appeared to be spherical, nanotriangles and irregular in shape. Catalytic application was observed for all the aqueous solution of leaves, quantity taken was 1 ml, 2 ml, 3 ml, 4 ml and 5 ml. Furthermore, prepared Ag nanoparticles are also used for seed germination.


Assuntos
Germinação , Química Verde , Nanopartículas Metálicas , Extratos Vegetais , Sementes , Prata , Prata/química , Nanopartículas Metálicas/química , Germinação/efeitos dos fármacos , Catálise , Química Verde/métodos , Sementes/crescimento & desenvolvimento , Sementes/química , Sementes/efeitos dos fármacos , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Microscopia Eletrônica de Transmissão
16.
Nat Commun ; 15(1): 7763, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237564

RESUMO

The challenge of transforming organized DNA structures into their metallized counterparts persists in the scientific field. In this context, utilizing DNA molecules modified with 7-deazapurine, provides a transformative solution. In this study, we present the solution structure of a DNA duplex that can be transformed into its metallized equivalent while retaining the natural base pairing arrangement through the creation of silver-modified Watson-Crick base pairs. Unlike previously documented X-ray structures, our research demonstrates the feasibility of preserving the intrinsic DNA self-assembly while incorporating AgI into the double helix, illustrating that the binding of silver does not disrupt the canonical base-pairing organization. Moreover, in our case, the uninterrupted AgI chain deviates from forming conventional straight linear chains; instead, it adheres to a helical arrangement dictated by the underlying DNA structure. This research challenges conventional assumptions and opens the door to precisely design structures based on the organization of highly stable Ag-DNA assemblies.


Assuntos
Pareamento de Bases , DNA , Conformação de Ácido Nucleico , Prata , Prata/química , DNA/química , Modelos Moleculares , Soluções
17.
Microb Cell Fact ; 23(1): 240, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39238019

RESUMO

Long-term antibiotic treatment results in the increasing resistance of bacteria to antimicrobials drugs, so it is necessary to search for effective alternatives to prevent and treat pathogens that cause diseases. This study is aimed for biological synthesis of silver Carthamus nanoparticles (Ag-Carth-NPs) to combat microbial biofilm formation and Pseudomonas aeruginosa virulence genes. Ag-Carth-NPs are synthesized using Carthamus tenuis aqueous extract as environmentally friendly method has no harmful effect on environment. General factorial design is used to optimize Ag-Carth-NPs synthesis using three variables in three levels are Carthamus extract concentration, silver nitrate concentration and gamma radiation doses. Analysis of response data indicates gamma radiation has a significant effect on Ag-Carth-NPs production. Ag-Carth-NPs have sharp peak at λ max 425 nm, small and spherical particles with size 20.0 ± 1.22 nm, high stability up to 240 day with zeta potential around - 43 ± 0.12 mV, face centered cubic crystalline structure and FT-IR spectroscopy shows peak around 620 cm-1 that corresponding to AgNPs that stabilized by C. tenuis extract functional moiety. The antibacterial activity of Ag-Carth-NPs against pathogenic bacteria and fungi was determined using well diffusion method. The MIC values of Ag-Carth-NPs were (6.25, 6.25, 3.126, 25, 12.5, 12.5, 25 and 12.5 µg/ml), MBC values were (12.5, 12.5, 6.25, 50, 25, 25, 50 and 25 µg/ml) and biofilm inhibition% were (62.12, 68.25, 90.12, 69.51, 70.61, 71.12, 75.51 and 77.71%) against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis, Candida tropicalis and Candida albicans respectively. Ag-Carth-NPs has bactericidal efficacy and significantly reduced the swarming, swimming motility, pyocyanin and protease production of P. aeruginosa. Furthermore, P. aeruginosa ToxA gene expression was significantly down regulated by 81.5%, while exoU reduced by 78.1%, where lasR gene expression reduction was 68%, while the reduction in exoU was 66% and 60.1% decrease in lasB gene expression after treatment with Ag-Carth-NPs. This activity is attributed to effect of Ag-Carth-NPs on cell membrane integrity, down regulation of virulence gene expression, and induction of general and oxidative stress in P. aeruginosa. Ag-Carth-NPs have no significant cytotoxic effects on normal human cell (Hfb4) but have IC50 at 5.6µg/mL against of HepG-2 cells. Limitations of the study include studies with low risks of silver nanoparticles for in vitro antimicrobial effects and its toxicity.


Assuntos
Antibacterianos , Biofilmes , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa , Prata , Biofilmes/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Nanopartículas Metálicas/química , Prata/farmacologia , Prata/química , Antibacterianos/farmacologia , Antibacterianos/química , Virulência/efeitos dos fármacos , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética
18.
Int J Nanomedicine ; 19: 9091-9107, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39258003

RESUMO

Purpose: Castration Resistant Prostate Cancer (CRPC) is characterized by poor prognosis and limited therapeutic options. AgNPs functionalized with glucose (G-AgNPs) were observed cytotoxic to CRPC cell lines (PC-3 and Du-145) and not LNCaP. This study aims to evaluate AgNPs and G-AgNPs' uptake mechanisms in these cells and understand their role in the selective effect against CRPC cells. Methods: Uptake of AgNPs and G-AgNPs was assessed through transmission electron microscopy (TEM). A microRNA (miRNAs) analysis approach was used to uncover the main molecular differences responsible for the endocytic mechanisms' regulation. Caveolin (Cav) 1 and 2 mRNA and protein levels were assessed in the three cell lines. Caveolae-dependent endocytosis was inhibited with genistein or siCav1- and siCav2- in PC-3 and Du-145 and resazurin assay was used to evaluate viability after AgNPs and G-AgNPs administration. Caveolae-dependent endocytosis was induced with Cav1+ and Cav2+ plasmids in LNCaP, resazurin assay was used to evaluate viability after AgNPs and G-AgNPs administration and TEM to assess their location. Results: AgNPs and G-AgNPs were not uptaked by LNCaP. miRNA analysis revealed 37 upregulated and 90 downregulated miRNAs. Functional enrichment analysis of miRNAs' targets resulted in enrichment of terms related to endocytosis and caveolae. We observed that Cav1 and Cav2 are not expressed in LNCaP. Inhibiting caveolae-dependent endocytosis in Du-145 and PC-3 led to a significative reduction of cytotoxic capacity of AgNPs and G-AgNPs and induction of caveolae-dependent endocytosis in LNCaP lead to a significative increase as well as their uptake by cells. Conclusion: This study shows the potential of these AgNPs as a new therapeutic approach directed to CRPC patients, uncovers caveolae-dependent endocytosis as the uptake mechanism of these AgNPs and highlights deregulation of Cav1 and Cav2 expression as a key difference in hormone sensitive and resistant PCa cells which may be responsible for drug resistance.


Assuntos
Cavéolas , Caveolina 1 , Endocitose , Nanopartículas Metálicas , MicroRNAs , Neoplasias de Próstata Resistentes à Castração , Prata , Masculino , Humanos , Endocitose/efeitos dos fármacos , Endocitose/fisiologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Cavéolas/metabolismo , Cavéolas/efeitos dos fármacos , Prata/química , Prata/farmacologia , Prata/farmacocinética , Caveolina 1/metabolismo , Caveolina 1/genética , Nanopartículas Metálicas/química , Linhagem Celular Tumoral , MicroRNAs/metabolismo , MicroRNAs/genética , Sobrevivência Celular/efeitos dos fármacos , Caveolina 2/metabolismo , Caveolina 2/genética , Antineoplásicos/farmacologia , Células PC-3
19.
PLoS One ; 19(9): e0310424, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39264924

RESUMO

The integration of nanoparticles into plant cryopreservation protocols holds great promise for improving the survival rates and recovery potential of explants. This study aimed to verify the effect of nanoparticles on the ex-vitro performance of cryopreservation-derived plants. Lamprocapnos spectabilis (L.) Fukuhara (bleeding heart) 'Gold Heart' and 'Valentine' cultivars were used as the plant material. The encapsulation-vitrification cryopreservation protocol of shoot tips included the preculture, encapsulation, dehydration, storage in liquid nitrogen, rewarming, and recovery steps. Gold (AuNPs), silver (AgNPs), or zinc oxide (ZnONPs) nanoparticles were added at varying concentrations, either into the preculture medium or the protective bead matrix during encapsulation. After the in vitro recovery, the plants were transferred to the glasshouse and subjected to detailed biometrical, biochemical and cytogenetic analyses. Nanoparticles had no evident effect on the acclimatization efficiency (80-100% survival) and leaf number in L. spectabilis 'Gold Heart'. Nonetheless, shoots developed from alginate beads supplemented with 5 ppm AuNPs were twice as long as the control, while the leaves of plants grown on the preculture medium with ZnONPs contained significantly more chlorophyll and had higher Leaf Soil-Plant Analysis Development (SPAD) values. Moreover, several NPs treatments stimulated the development of leaves, including their surface area, length, and perimeter. Higher ZnONPs levels enhanced also the replication process, resulting in higher nuclear DNA content. As for L. spectabilis 'Valentine', alginate augmentation with 5 ppm AgNPs or 5 ppm ZnONPs stimulated the elongation of shoots. There was also a tendency suggesting a positive influence of 5 ppm AgNPs in the alginate bead matrix on foliar growth. The effect of nanoparticles on the content of flavonoids, anthocyanins, and stress markers in the plants varied depending on the treatment and cultivar, but also on the organ studied (leaf or stem). Overall, L. spectabilis 'Gold Heart' was more stress-tolerant and genetically stable than 'Valentine' judging by the activity of Photosystem II (PSII) and flow cytometric analyses, respectively. The complex effects of nanoparticles on survival, biometric parameters, physiological responses, and cytogenetic events underscore the intricate interplay between nanoparticles and plant systems. Nonetheless, our research confirmed the positive effect of nanoparticles on the ex-vitro growth and development of L. spectabilis plants after cryostorage.


Assuntos
Criopreservação , Nanopartículas Metálicas , Criopreservação/métodos , Nanopartículas Metálicas/química , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Ouro/química , Folhas de Planta/efeitos dos fármacos , Clorofila/metabolismo , Prata/farmacologia
20.
Int J Nanomedicine ; 19: 9227-9253, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39267724

RESUMO

Purpose: Oral squamous cell carcinoma is the most common type of malignant tumor in the head and neck region. Despite advancements, metastasis and recurrence rates remain high, and patient survival has not significantly improved. Although miRNA therapies are promising for cancer gene therapy, their applications in treating oral cancer are limited. Targeted medication delivery systems based on nanotechnology offer an efficient way to enhance oral cancer treatment efficacy. Methods: We synthesized nanosilver (AgNPs) and loaded them with the tumor suppressor miR-181a-5p. In vitro experiments were conducted to investigate the inhibitory effects of AgNPs and their composites on the malignant behavior of oral cancer cell lines. The xenograft experiment was utilized to examine their effects on tumorigenesis and the potential molecular mechanisms involved. Results: The nanosilver exhibited a spherical morphology with a size distribution ranging from 50 to 100 nm. They exhibited a distinct absorption peak at 330 nm and could be excited to emit green fluorescence. The biocompatible AgNPs effectively shielded miRNA from degradation by RNase and serum. The nanocomposites significantly inhibited the proliferation, invasion, migration, and colony formation of oral cancer cell lines. Notably, treatment with the nanocomposites resulted in substantial tumor growth suppression in the xenograft model. Mechanistically, these composites directly targeted BCL2 and exerted their antitumor effects by suppressing the ß-catenin signaling pathway and other downstream genes without inducing acute toxicity. Conclusion: Collectively, the findings demonstrate that the miR-181a-5p/AgNPs combination significantly impedes the growth and progression of oral cancer both in vitro and in vivo, highlighting a pivotal role for the ß-catenin signaling pathway. This multifaceted approach holds promise as a prospective therapeutic strategy for oral cancer management in the future.


Assuntos
Nanopartículas Metálicas , MicroRNAs , Neoplasias Bucais , Prata , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , MicroRNAs/administração & dosagem , MicroRNAs/genética , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/patologia , Humanos , Linhagem Celular Tumoral , Nanopartículas Metálicas/química , Camundongos , Prata/química , Prata/farmacologia , Proliferação de Células/efeitos dos fármacos , Camundongos Nus , Movimento Celular/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética
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