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1.
Biomaterials ; 312: 122721, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39106817

RESUMEN

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.


Asunto(s)
Células Asesinas Naturales , Pulmón , Nanopartículas del Metal , Infecciones por Orthomyxoviridae , Plata , Animales , Plata/química , Plata/farmacología , Nanopartículas del Metal/química , Pulmón/virología , Pulmón/patología , Pulmón/efectos de los fármacos , Infecciones por Orthomyxoviridae/prevención & control , Infecciones por Orthomyxoviridae/tratamiento farmacológico , Infecciones por Orthomyxoviridae/virología , Ratones , Células Asesinas Naturales/efectos de los fármacos , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/virología , Ratones Endogámicos C57BL , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Antivirales/farmacología , Antivirales/uso terapéutico , Femenino , Activación de Linfocitos/efectos de los fármacos
2.
Sci Rep ; 14(1): 20744, 2024 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-39251604

RESUMEN

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.


Asunto(s)
Germinación , Tecnología Química Verde , Nanopartículas del Metal , Extractos Vegetales , Semillas , Plata , Plata/química , Nanopartículas del Metal/química , Germinación/efectos de los fármacos , Catálisis , Tecnología Química Verde/métodos , Semillas/crecimiento & desarrollo , Semillas/química , Semillas/efectos de los fármacos , Extractos Vegetales/química , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Microscopía Electrónica de Transmisión
3.
Sci Rep ; 14(1): 20986, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39251688

RESUMEN

Silver nanowires (AgNWs) have excellent flexibility, unique optical transmittance and high conductivity. The polyol process is appropriate for preparing AgNWs due to its simplicity, effectiveness, low cost, and high yield. This work aims to investigate the effect of preparation parameters of the polyol process on the silver nanowires properties. The parameters include the controlling agent, molecular weight of the polyvinylpyrrolidone (PVP), the temperature, and the reducing agent. The amount of silver nanoparticles formed during preparation was used to determine the optimum preparation conditions. The transmission electron microscope (TEM) images showed minimal amount of Ag nanoparticles when using mixed molecular weight of PVP-40K, and PVP-1.3M at 150 °C with the assistance of copper chloride as a controlling agent. The prepared AgNWs had an average length of 3.7 µm and aspect ratio of 15.3. The fabricated electrodes were characterized using a scanning electron microscope (SEM) and four probe resistivity measurements. The electrical measurement of the AgNWs electrodes indicated that the surfactant thickness is a critical parameter in having low sheet resistance electrodes. Also, the optical transmission was affected by the amount of nanoparticles. The prepared electrode with high concentration of AgNWs and a minimal amount of nanoparticles exhibited 80% optical transmission.

4.
Sci Total Environ ; 953: 176006, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39241875

RESUMEN

The emergence of nanotechnology has opened new avenues for enhancing pest control strategies through the development of nanopesticides. Green-fabricated nanoparticles, while promising due to their eco-friendly synthesis methods, may still pose risks to biodiversity and ecosystem stability. The potential toxic effects of nanomaterials on ecosystems and human health raise important questions about their real-world application. Understanding the dose-response relationships of nanopesticides, both in terms of pest control efficacy and non-target organism safety, is crucial for ensuring their sustainable use in agricultural settings. This review delves into the complexities of silver nanopesticides, exploring their interactions with arthropod species, modes of action, and underlying mechanisms of toxicity. It discusses critical issues concerning the emergence of silver nanopesticides, spanning their mosquitocidal efficacy to environmental impact and safety considerations. While nano­silver has shown promise in targeting insect pests, there is a lack of systematic research comparing its effects on different arthropod subclasses. Moreover, factors influencing nanotoxicity, such as nanoparticle size, charge, and surface chemistry, require further investigation to optimize the design of eco-safe nanoparticles for pest control. By elucidating the mechanisms by which nanoparticles interact with pests and non-target organisms, we can enhance the specificity and effectiveness of nanopesticides while minimizing unintended ecological consequences.

5.
Int J Pharm ; 665: 124692, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39265849

RESUMEN

In modern times, many antibiotics have become less effective as microorganisms develop resistance. Besides antibiotic resistance, another bacterial strategy that contributes to the capacity to withstand antimicrobials is biofilm formation. Because of these bacterial survival strategies, the desired response cannot be achieved with conventional treatment. Considering the limited discovery of new compounds, the most logical approach is to reconstruct existing antimicrobial molecules with nano-drug delivery systems. With this scientific approach, the aim of the study is to develop a novel nano-antibiotic hydrogel formulation containing silver nanoparticles, chitosan, and amoxicillin. Endodontic disease was used as a model of biofilm-mediated infection, and the antibacterial activity of nano-antibiotic hydrogel was evaluated with the E. faecalis standard bacterial strain. By adopting the Box-Behnken design for the optimisation of formulation variables, an innovative pharmaceutical formulation with antimicrobial and antibiofilm activity was successfully obtained. Further characterisation studies, including nanoparticle characterisation, in vitro cytotoxicity, and ex vivo activity studies, were carried out on dental samples using the optimised formulation. All results were compared with antimicrobial agents routinely used in endodontic treatment. The findings mainly conclude that the optimised nano-antibiotic hydrogel may be an alternative antimicrobial formulation since it is non-cytotoxic and exhibits high antibiofilm activity.

6.
Sensors (Basel) ; 24(17)2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39275763

RESUMEN

Photodetectors and gas sensors are vital in modern technology, spanning from environmental monitoring to biomedical diagnostics. This paper explores the UV detection and gas sensing properties of a zinc oxide (ZnO) nanorod array (ZNA) grown on silver nanowire mesh (AgNM) using a hydrothermal method. We examined the impact of different zinc acetate precursor concentrations on their properties. Results show the AgNM forms a network with high transparency (79%) and low sheet resistance (7.23 Ω/□). A sol-gel ZnO thin film was coated on this mesh, providing a seed layer with a hexagonal wurtzite structure. Increasing the precursor concentration alters the diameter, length, and area density of ZNAs, affecting their performance. The ZNA-AgNM-based photodetector shows enhanced dark current and photocurrent with increasing precursor concentration, achieving a maximum photoresponsivity of 114 A/W at 374 nm and a detectivity of 6.37 × 1014 Jones at 0.05 M zinc acetate. For gas sensing, the resistance of ZNA-AgNM-based sensors decreases with temperature, with the best hydrogen response (2.71) at 300 °C and 0.04 M precursor concentration. These findings highlight the potential of ZNA-AgNM for high-performance UV photodetectors and hydrogen gas sensors, offering an alternative way for the development of future sensing devices with enhanced performance and functionality.

7.
Int J Mol Sci ; 25(17)2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39273259

RESUMEN

Wound healing is a dynamic process involving a complex interaction between many cells and mediators. Magnesium (Mg) is an essential element for cell stabilization. Mg was reported to stimulate the proliferation and migration of endothelial cells in angiogenesis in vitro. However, the function of Mg in wound healing is not known. We observed that the expression level of Mg in human wound tissue fluid was only 10% of that found in human blood serum. To confirm whether Mg is a suitable wound dressing material, we fabricated a Mg- or Mg-silver (Ag)-based polyethylene dressing to study its effect on wound healing. We observed that Mg and Ag were stably preserved in the constructed material and were able to be rapidly released in the moist environment. We also observed that the Mg-based dressing had good cellular compatibility without harmful extractables. Furthermore, Mg enhanced the antibacterial activity of Ag. In line with the observed increase in fibroblast migration in vitro, the Mg-Ag-based dressing improved acute and chronic wound repairs via an increase in neovascularization and basal cell proliferation. The present results show that a Mg-Ag-based coating can be manufactured as an optimal dressing for adjuvant wound therapy.


Asunto(s)
Vendajes , Magnesio , Plata , Cicatrización de Heridas , Cicatrización de Heridas/efectos de los fármacos , Magnesio/farmacología , Plata/química , Plata/farmacología , Humanos , Animales , Proliferación Celular/efectos de los fármacos , Piel/efectos de los fármacos , Piel/metabolismo , Piel/lesiones , Movimiento Celular/efectos de los fármacos , Regeneración/efectos de los fármacos , Masculino , Antibacterianos/farmacología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Ratones , Neovascularización Fisiológica/efectos de los fármacos
8.
Int J Mol Sci ; 25(17)2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39273279

RESUMEN

The rapid detection of contaminants in water resources is vital for safeguarding the environment, where the use of eco-friendly materials for water monitoring technologies has become increasingly prioritized. In this context, the role of biocomposites in the development of a SERS sensor is reported in this study. Grafted chitosan was employed as a matrix support for Ag nanoparticles (NPs) for the surface-enhanced Raman spectroscopy (SERS). Chitosan (CS) was decorated with thiol and carboxylic acid groups by incorporating S-acetyl mercaptosuccinic anhydride (SAMSA) to yield CS-SAMSA. Then, Ag NPs were immobilized onto the CS-SAMSA (Ag@CS-SAMSA) and characterized by spectral methods (IR, Raman, NIR, solid state 13C NMR with CP-MAS, XPS, and TEM). Ag@CS-SAMSA was evaluated as a substrate for SERS, where methylene blue (MB) was used as a model dye adsorbate. The Ag@CS-SAMSA sensor demonstrated a high sensitivity (with an enhancement factor ca. 108) and reusability over three cycles, with acceptable reproducibility and storage stability. The Raman imaging revealed a large SERS effect, whereas the MB detection varied from 1-100 µM. The limits of detection (LOD) and quantitation (LOQ) of the biocomposite sensor were characterized, revealing properties that rival current state-of-the-art systems. The dye adsorption profiles were studied via SERS by fitting the isotherm results with the Hill model to yield the ΔG°ads for the adsorption process. This research demonstrates a sustainable dual-function biocomposite with tailored adsorption and sensing properties suitable for potential utility in advanced water treatment technology and environmental monitoring applications.


Asunto(s)
Quitosano , Nanopartículas del Metal , Plata , Espectrometría Raman , Quitosano/química , Espectrometría Raman/métodos , Plata/química , Nanopartículas del Metal/química , Límite de Detección , Colorantes/química , Colorantes/análisis , Cationes/análisis , Contaminantes Químicos del Agua/análisis , Azul de Metileno/química
9.
Oxf Med Case Reports ; 2024(9): omae106, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39281335

RESUMEN

Silver hair in a neonate is an uncommon occurrence. The aetiology of this condition is varied and is associated with immunodeficiency disorders such as Griscelli syndrome and Chédiak-Higashi syndrome. A preterm neonate with Griscelli syndrome type 2 might present with just silver colour staining of hair including the lanugo hair with no other complications. In those with associated systemic abnormalities such as congenital pulmonary airway malformation, further evaluation for conditions such as Menke-Kinke hair syndrome is required. In this case series, we describe two unique cases of silver hair syndrome in preterm neonates with their clinical description, course in the hospital, role of hair mount and genetic testing for further identification and diagnosis of this disorder.

10.
Front Microbiol ; 15: 1416411, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39282556

RESUMEN

The aquatic environment, independent of their host, is more favorable to pathogenic bacteria than the terrestrial environment. Consequently, pathogenic bacteria can reach very high densities around aquatic animals and can cause high mortality. The conventional approach, such as antibiotics, has minimal effectiveness. Additionally, due to the emergence of (multiple) resistance, their use is under intense scientific and public scrutiny. Hence, there is a need for the development of alternative control techniques, with an emphasis on prevention, which is likely to be more cost-effective. In this study, a potential bacterial strain Cytobacillus firmus was isolated from polluted river sediment and characterized using a comprehensive range of techniques including biochemical, 16S rRNA sequencing and antibiogram assay. The pathogenicity of the bacteria was tested in vivo on Labeo rohita fingerlings found as non-pathogenic. Further, the bacteria were found to synthesize silver nanoparticles (AgNPs) using AgNO3 as a substrate. The obtained AgNPs were characterized by various methods, including UV-vis spectroscopy, FTIR (Fourier-transform infrared spectroscopy), and Transmission Emission Microscopy (TEM). The study found that the AgNPs were 20 nm in size on average. The antimicrobial activity of synthesized AgNPs was examined against the model freshwater pathogenic bacteria, Edwardsiella tarda and both the MIC (Minimum Inhibitory Concentration) and MBC (Minimum Bactericidal Concentration) were 0.156 µM, while biofilm inhibition activity was also observed at 0.156 µM. The AgNPs showed no haemolytic activity at 0.313 µM. Our findings suggest that C. firmus mediated bacteriogenic AgNPs modulate the activity of common pathogenic bacteria E. tarda. The thoroughness of our research process gives us confidence in the potential of applying AgNPs in aquaculture as a considerable strategy to control the E. tarda infection.

11.
Int J Nanomedicine ; 19: 9317-9332, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39282575

RESUMEN

Purpose: : Polyvinyl alcohol-capped silver nanostructures (cAgNSs) were investigated in order to enhance the cytotoxicity, pro-apoptotic, and oxidant patterns of in human laryngeal carcinoma Hep-2 cells by employing a 50 mT electromagnetic field (LEMF) for 30 min. Methods: Wet chemical reduction was used to synthesize the cAgNSs, and after they had been capped with polyvinyl alcohol, they were specifically examined for particle size analysis and structural morphology. To visualize how the silver may attach to the protein targets, a molecular docking study was conducted. Estimation of cytotoxicity, cell cycle progression supported by mRNA expression of three apoptotic-promoting genes and one apoptotic-resisting. Results: Particle size analysis results were a mean particle size of 157.3±0.5 nm, zeta potential value of -29.6 mV±1.5 mV, and polydispersity index of 0.31±0.05. Significantly reduction of IC50 against Hep-2 cells by around 6-fold was concluded. Also, we obtained suppression of the proliferation of Hep-2 cells, especially in the G0/G1 and S phases. Significant enhanced mRNA expression revealed enhanced induced CASP3, p53, and Beclin-1 mediated pro-apoptosis and induced NF-κB mediated autophagy in Hep-2 cells. Augmented levels of GR, ROS and MDA as oxidative stress biomarkers were also obtained. HE staining of Hep-2 cells exposed to cAgNSs and LEMF confirmed the enhanced apoptotic potential comparatively. Conclusion: By conclusion, the developed nano-sized structures with the aid of extremely-low frequency electromagnetic field were successful to fortify the anti-cancer profile of cAgNSs in Hep-2 cells.


Asunto(s)
Apoptosis , Neoplasias Laríngeas , Nanopartículas del Metal , Alcohol Polivinílico , Plata , Humanos , Neoplasias Laríngeas/patología , Apoptosis/efectos de los fármacos , Plata/química , Plata/farmacología , Línea Celular Tumoral , Nanopartículas del Metal/química , Alcohol Polivinílico/química , Alcohol Polivinílico/farmacología , Tamaño de la Partícula , Campos Electromagnéticos , Proliferación Celular/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/química , Simulación del Acoplamiento Molecular , Nanoestructuras/química , Ciclo Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos
12.
BMC Oral Health ; 24(1): 1098, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39285379

RESUMEN

OBJECTIVE: To develop a novel calcium silver zeolite (Ca-Ag-Zeo) and assess its biocompatibility, physiochemical properties and antimicrobial effects. METHODS: Ca-Ag-Zeo was synthesized using ion-exchange method with calcium chloride, silver nitrate and Zeolite X (Zeo). Silver zeolite X (Ag-Zeo) and Zeo were set as control. The chemical structure, morphology, crystal structure and elemental composition of Ca-Ag-Zeo was characterized by X-ray diffraction spectrum, scanning electron microscopy, transmission electron microscopy and energy dispersive spectroscopy, respectively. Its biocompatibility on the human gingival fibroblasts was assessed by cell counting kit-8 assay. Its physiochemical properties were determined by the released calcium and silver ion using Inductive Coupled Plasma Emission Spectrometry for up to 12 weeks. The antimicrobial properties on Streptococcus mutans, Lactobacillus acidophilus, Lactobacillus casei, and Candida albicans were assessed by minimum bactericidal concentration (MBC) or minimum fungicidal concentration (MFC) assay. RESULTS: Ca-Ag-Zeo with a hexagonal cage structure was synthesized. As for biocompatibility, the half-maximal inhibitory concentration (± SD in mg/mL) of Ca-Ag-Zeo, Ag-Zeo and Zeo in human gingival fibroblasts were 0.52 ± 0.05, 0.15 ± 0.01 and 3.35 ± 0.58, respectively (Zeo > Ca-Ag-Zeo > Ag-Zeo; p < 0.05). As for physiochemical properties, the accumulated ion release (± SD in mg) of Ca-Ag-Zeo, Ag-Zeo and Zeo were 0.011 ± 0.003, 0 and 0 for calcium ion, respectively (Ca-Ag-Zeo > Ag-Zeo, Zeo; p < 0.001), and 0.213 ± 0.032, 0.209 ± 0.019 and 0 for silver ion, respectively (Ca-Ag-Zeo, Ag-Zeo > Zeo; p < 0.001). As for anti-microbial ability, the MBC/MFC (mg/mL) of Ca-Ag-Zeo, Ag-Zeo and Zeo were 32, 16 and > 256 against Streptococcus mutans; 32, 16, > 256 against Lactobacillus acidophilus; 16, 16, and 256 against Lactobacillus casei; 0.25, 0.125; and 2, 1, > 256 against Candida albicans, respectively. CONCLUSION: A novel Ca-Ag-Zeo was developed. It presented better biocompatibility compared to Ag-Zeo. It released calcium and silver ions sustainably, and it could inhibit the growth of common cariogenic microorganisms.


Asunto(s)
Calcio , Candida albicans , Caries Dental , Fibroblastos , Pruebas de Sensibilidad Microbiana , Plata , Streptococcus mutans , Zeolitas , Humanos , Zeolitas/farmacología , Zeolitas/química , Streptococcus mutans/efectos de los fármacos , Candida albicans/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Caries Dental/prevención & control , Caries Dental/microbiología , Plata/farmacología , Plata/química , Lactobacillus acidophilus/efectos de los fármacos , Difracción de Rayos X , Encía/efectos de los fármacos , Encía/citología , Lacticaseibacillus casei/efectos de los fármacos , Microscopía Electrónica de Rastreo , Materiales Biocompatibles/farmacología , Microscopía Electrónica de Transmisión , Ensayo de Materiales , Nitrato de Plata/farmacología , Antibacterianos/farmacología , Antiinfecciosos/farmacología
13.
Heliyon ; 10(17): e36118, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39286104

RESUMEN

In this study, we green synthesized silver nanoparticles (Ag Nps) from Hybanthus enneaspermus leaves (HE-Ag NPs) and evaluated their antimicrobial and wound-healing properties. The synthesized HE-Ag NPs were characterized using various techniques, revealing face-centered polygonal structures, a well-dispersed appearance, and an average particle size of 42-51 nm. The antimicrobial effects of HE-Ag NPs and their embedded cotton fabrics were tested against several pathogens, showing effective inhibition of growth. The cytotoxicity and anti-inflammatory properties of HE-Ag NPs were assessed using MTT assays on L929 and RAW 264.7 cells and by measuring inflammatory cytokine levels in LPS-treated RAW 264.7 cells. HE-Ag NPs did not affect the viability of L929 and RAW 264.7 cells and significantly reduced inflammatory cytokine levels. In vivo studies using an excision wound model demonstrated that HE-Ag NPs-loaded ointment significantly increased hydroxyproline, total protein, and antioxidant levels and enhanced the wound contraction rate. These findings suggest that HE-Ag NPs have potent antimicrobial properties and promote wound healing, indicating their potential for use in topical ointments for wound care.

14.
Heliyon ; 10(17): e36974, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39286151

RESUMEN

Electrode modification has been one of the most active areas of interest in electrochemistry research. Hence, the investigation of the effects of chemically and electrochemically modified GCE nano-films on the NPs electrochemical properties. The electrochemistry of nano-films of Ag NPs, Au NPs and bimetallic Ag-Au (1:2) NPs of chemical citrate reduction synthesis drop coated (DCT) and electro-deposition method (EDP) are reported. The Chemically synthesized NPs were confirmed through FT-IR, UV-visible, XRD and SEM techniques while electro-deposited NPs were ascertained by double-pulsed chrono-amperometry and electrochemical impedance spectroscopy (EIS). The nano films; GCE/Ag NPs, GCE/Au NPs and GCE/Ag-Ag (1:2) NPs in 0.1 M HCl supporting electrolyte were studied via Cyclic Voltammetry (CV) and Differential Pulse Voltammetry (DPV) techniques. Generally the DCT nano films were electrochemically superior to the EDP film in terms of current intensities and GCE/Ag-Au (1:2) NPs showed enhanced α (0.019), k s (0.01 s-1), Q (3.6 × 10-9 C), Γ (5.3 × 10-13molescm-2) and D (1.31 × 10-1 cm2s-1), indicating better physicochemical properties for possible sensing applications compared to electro-deposited GCE nano-films.

15.
Biochem Biophys Rep ; 40: 101818, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39290346

RESUMEN

Recently, we have reported that biogenic silver/silver chloride nanoparticles from Asparagus racemosus (A. racemosus-AgCl-NPs) and Kaempferia rotunda (K. rotunda-Ag/AgCl-NPs) inhibited different cancer cells by inducing apoptosis and several genes alteration. Here for the first time, we assessed the effects of these two nanoparticles on human lung (A549) and hepatocellular (SMMC-7721) carcinoma cell lines. A. racemosus-AgCl-NPs and K. rotunda-Ag/AgCl-NPs inhibited A549 cell growth with IC50 values of 22.7 and 59.7 µg/ml and the calculated IC50 values for SMMC-7721 cell were 89.3 and 126.3 µg/ml, respectively. A. racemosus-AgCl-NPs exerted higher cytotoxicity against HEK293T cells than doxorubicin and K. rotunda-Ag/AgCl-NPs. Both the nanoparticles induced apoptosis in A549 and SMMC-7721 cell lines. A significant rise of early apoptotic cells and late apoptotic cells was found for A549 cells after treatment with A. racemosus-AgCl-NPs and stained with FITC-annexin V/PI. Apoptosis in A549 cells was further confirmed by monitoring the alteration of the expression level of several genes using real-time PCR and cell cycle arrest by flowcytometry after treatment with A. racemosus-AgCl-NPs. The expression of STAT-3, TNFα, and EGFR genes was decreased with the increase of caspase-8, FAS, and FADD gene expression. G2/M cell cycle phase was arrested after treatment of A549 cells with A. racemosus-AgCl-NPs.

17.
Artículo en Inglés | MEDLINE | ID: mdl-39292309

RESUMEN

Synthesis of silver nanoparticles (Ag NPs) using microalgae is gaining recognition for its environmentally friendly and cost-effective nature while maintaining high activity of NPs. In the present study, Ag NPs were synthesized using a methanolic extract of Chlorella vulgaris and subjected to calcination. The X-ray diffraction (XRD) analysis showed a crystalline nature of the products with Ag2O and Ag phases with an average crystalline size of 16.07 nm before calcination and an Ag phase with 24.61 nm crystalline size after calcination. Fourier transform infrared spectroscopy (FTIR) revealed the capping functional groups on Ag NPs, while scanning electron microscopy (SEM) displayed their irregular morphology and agglomeration after calcination. The organic coating was examined by energy-dispersive X-ray spectroscopy (EDX) and thermogravimetric (TGA) analyses, confirming the involvement of the metabolites. The UV-Vis analysis showed a difference in optical properties due to calcination. Synthesized Ag NPs were applied for the photodegradation of hazardous dye Brilliant Blue R in visible light. Different values of light intensity, catalyst dose, initial dye concentration, and pH were tested to identify the optimal set of operating conditions. The highest degradation efficiency of 90.6% with an apparent rate constant of 0.04402 min-1 was achieved after 90 min of irradiation in the highest tested catalyst dosage.

18.
Discov Nano ; 19(1): 150, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39287718

RESUMEN

This study explores the potential of zinc and silver nanocomposites, synthesized with ß-lactoglobulin, a whey protein, in promoting wound healing, using the C57BL/6J mouse model. Our research is distinct in its dual focus: assessing the antimicrobial efficacy of these nanocomposites and their impact on wound healing processes. The antimicrobial properties were investigated through minimum inhibitory concentration (MIC) assessments and colony-forming unit (CFU) tests, providing insights into their effectiveness against wound-associated microorganisms. Notably, the formulation's effective antibacterial concentration did not exhibit toxicity to mouse fibroblasts. A key aspect of our methodology involved the use of a stereoscopic microscope for detailed monitoring of the wound closure process. Additionally, the distribution and potential systemic effects of the zinc and silver ions were analyzed using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). This analysis was crucial in evaluating metal ion absorption through the wound site and estimating any toxic effects on the body. Our findings are particularly significant in the field of regenerative medicine. Transmission electron microscopy (TEM) revealed that the tested nanocomposites notably enhanced collagen deposition, a vital component in the wound healing process. Furthermore, a reduction in glycogen levels in hepatocytes was observed following treatment with these metal-protein dressings. This novel finding warrants further investigation. Overall, our findings highlight the diverse roles of zinc and silver nanocomposites in wound healing. This study not only contributes to our understanding of metal-protein complexes in tissue regeneration but also opens new avenues for research into the delivery mechanisms of such treatments for hard-to-heal wounds.

19.
J Burn Care Res ; 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39288163

RESUMEN

Recognition of invasive burn wound sepsis as a major cause of morbidity and mortality in burn injured patients has profoundly changed the management of burn wounds and its associated complications. The development of effective topical antimicrobial therapy is one of the last major developments of modern burn care and has been driven by major world events and scientific breakthroughs. Topical antimicrobial burn care has evolved from the use of anecdotal remedies to scientific breakthroughs such as Moyer's successful dilution of silver nitrate solution, Fox's described benefit of silver sulfadiazine use in animal models, and Pruitt's dramatic improvement in post-burn mortality using topical mafenide acetate in burn wounds. The objective of this manuscript is to review the definition of burn wound sepsis and highlight the major developments and breakthroughs in topical burn wound care throughout history. This includes historical events like major wars or domestic fires that have influenced or impacted the understanding and treatment of burn wounds. Newer advances in topical antimicrobial care such as nanosilvers and dressing technologies that improve the morbidity and mortality associated with burn wound sepsis and novel approaches to management will also be discussed. To improve burn care, it is prudent to look to the past and learn from the experiences of those who contributed to the control of burn wound sepsis.

20.
ACS Nano ; 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39288200

RESUMEN

DNA-stabilized silver nanoclusters (AgN-DNAs) have sequence-tuned compositions and fluorescence colors. High-throughput experiments together with supervised machine learning models have recently enabled design of DNA templates that select for AgN-DNA properties, including near-infrared (NIR) emission that holds promise for deep tissue bioimaging. However, these existing models do not enable simultaneous selection of multiple AgN-DNA properties, and require significant expert input for feature engineering and class definitions. This work presents a model for multiobjective, continuous-property design of AgN-DNAs with automatic feature extraction, based on variational autoencoders (VAEs). This model is generative, i.e., it learns both the forward mapping from DNA sequence to AgN-DNA properties and the inverse mapping from properties to sequence, and is trained on an experimental data set of DNA sequences paired with AgN-DNA fluorescence properties. Experimental testing shows that the model enables effective design of AgN-DNA emission, including bright NIR AgN-DNAs with 4-fold greater abundance compared to training data. In addition, Shapley analysis is employed to discern learned nucleobase patterns that correspond to fluorescence color and brightness. This generative model can be adapted for a range of biomolecular systems with sequence-dependent properties, enabling precise design of emerging biomolecular nanomaterials.

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