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1.
Sci Rep ; 11(1): 8692, 2021 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-33888738

RESUMEN

A metal nanoparticle composite, namely TPNT1, which contains Au-NP (1 ppm), Ag-NP (5 ppm), ZnO-NP (60 ppm) and ClO2 (42.5 ppm) in aqueous solution was prepared and characterized by spectroscopy, transmission electron microscopy, dynamic light scattering analysis and potentiometric titration. Based on the in vitro cell-based assay, TPNT1 inhibited six major clades of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with effective concentration within the range to be used as food additives. TPNT1 was shown to block viral entry by inhibiting the binding of SARS-CoV-2 spike proteins to the angiotensin-converting enzyme 2 (ACE2) receptor and to interfere with the syncytium formation. In addition, TPNT1 also effectively reduced the cytopathic effects induced by human (H1N1) and avian (H5N1) influenza viruses, including the wild-type and oseltamivir-resistant virus isolates. Together with previously demonstrated efficacy as antimicrobials, TPNT1 can block viral entry and inhibit or prevent viral infection to provide prophylactic effects against both SARS-CoV-2 and opportunistic infections.


Asunto(s)
Oro/farmacología , Subtipo H1N1 del Virus de la Influenza A/fisiología , Subtipo H5N1 del Virus de la Influenza A/fisiología , Plata/farmacología , Óxido de Zinc/farmacología , /metabolismo , Antivirales/química , Antivirales/farmacología , Farmacorresistencia Viral/efectos de los fármacos , Aditivos Alimentarios/farmacología , Oro/química , Células HEK293 , Humanos , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Subtipo H5N1 del Virus de la Influenza A/efectos de los fármacos , Nanopartículas del Metal/química , Nanocompuestos/química , Oseltamivir/farmacología , Tamaño de la Partícula , Unión Proteica/efectos de los fármacos , Plata/química , Glicoproteína de la Espiga del Coronavirus/metabolismo , Internalización del Virus/efectos de los fármacos , Óxido de Zinc/química
2.
Int J Nanomedicine ; 16: 2689-2702, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33854315

RESUMEN

Background: The COVID-19 pandemic is requesting highly effective protective personnel equipment, mainly for healthcare professionals. However, the current demand has exceeded the supply chain and, consequently, shortage of essential medical materials, such as surgical masks. Due to these alarming limitations, it is crucial to develop effective means of disinfection, reusing, and thereby applying antimicrobial shielding protection to the clinical supplies. Purpose: Therefore, in this work, we developed a novel, economical, and straightforward approach to promote antimicrobial activity to surgical masks by impregnating silver nanoparticles (AgNPs). Methods: Our strategy consisted of fabricating a new alcohol disinfectant formulation combining special surfactants and AgNPs, which is demonstrated to be extensively effective against a broad number of microbial surrogates of SARS-CoV-2. Results: The present nano-formula reported a superior microbial reduction of 99.999% against a wide number of microorganisms. Furthermore, the enveloped H5N1 virus was wholly inactivated after 15 min of disinfection. Far more attractive, the current method for reusing surgical masks did not show outcomes of detrimental amendments, suggesting that the protocol does not alter the filtration effectiveness. Conclusion: The nano-disinfectant provides a valuable strategy for effective decontamination, reuse, and even antimicrobial promotion to surgical masks for frontline clinical personnel.


Asunto(s)
Antiinfecciosos/farmacología , Desinfectantes/farmacología , Máscaras , Nanopartículas del Metal/química , Plata/farmacología , Animales , Antiinfecciosos/administración & dosificación , Antiinfecciosos/química , Antivirales/química , Antivirales/farmacología , /transmisión , Embrión de Pollo , Desinfectantes/administración & dosificación , Desinfectantes/química , Desinfección/métodos , Dispersión Dinámica de Luz , Equipo Reutilizado , Humanos , Subtipo H5N1 del Virus de la Influenza A/efectos de los fármacos , Máscaras/virología , Nanopartículas del Metal/administración & dosificación , Pruebas de Sensibilidad Microbiana , Plata/química , Espectroscopía Infrarroja por Transformada de Fourier , Textiles , Difracción de Rayos X
3.
Braz J Biol ; 82: e232434, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33681895

RESUMEN

Many pathogenic strains have acquired multidrug-resistant patterns in recent a year, which poses a major public health concern. The growing need for effective antimicrobial agents as novel therapies against multidrug-resistant pathogens has drawn scientist attention toward nanotechnology. Silver nanoparticles are considered capable of killing multidrug-resistant isolates due to their oligo-dynamic effect on microorganisms. In this research study NPs were synthesized using the gram-positive bacteria Lactobacillus bulgaricus and its activity against selected pathogenic strains. Lactobacillus bulgaricus pure cultures were isolated from raw milk and grown in "De Man, Rogasa, and Sharp" broth for synthesis of nanoparticles. Lactobacillus bulgaricus culture was centrifuged and Cell- free supernatant of it was employed with aqueous silvery ions and evaluated their antibacterial activities against bacterial strains i.e. Staphylococcus aureus, Staphylococcus epidermidis and Salmonella typhi using agar well diffusion assay. Antibiotic profiling against selected pathogenic strains were also conducted using disc diffusion method. The synthesis and characterization of silver nanoparticles were monitored primarily by the conversion of the pale-yellow color of the mixture into a dark-brown color and via ultraviolet-visible absorption spectroscopy and Scanning electron microscopy respectively. The result showed that that AgNPs with size (30.65-100 nm) obtained from Lactobacillus bulgaricus were found to exhibit antibacterial activities against selected bacterial strains. Taken together, these findings suggest that Lactobacillus bulgaricus has great potential for the production of AgNPs with antibacterial activities and highly effective in comparison to tested antibiotics.


Asunto(s)
Antiinfecciosos , Lactobacillus delbrueckii , Nanopartículas del Metal , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Plata/farmacología
4.
Bone Joint J ; 103-B(3): 423-429, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33641432

RESUMEN

Periprosthetic joint infection (PJI) is one of the most dreaded complications after arthroplasty surgery; thus numerous approaches have been undertaken to equip metal surfaces with antibacterial properties. Due to its antimicrobial effects, silver is a promising coating for metallic surfaces, and several types of silver-coated arthroplasty implants are in clinical use today. However, silver can also exert toxic effects on eukaryotic cells both in the immediate vicinity of the coated implants and systemically. In most clinically-used implants, silver coatings are applied on bulk components that are not in direct contact with bone, such as in partial or total long bone arthroplasties used in tumour or complex revision surgery. These implants differ considerably in the coating method, total silver content, and silver release rates. Safety issues, such as the occurrence of argyria, have been a cause for concern, and the efficacy of silver coatings in terms of preventing PJI is also controversial. The application of silver coatings is uncommon on parts of implants intended for cementless fixation in host bone, but this option might be highly desirable since the modification of implant surfaces in order to improve osteoconductivity can also increase bacterial adhesion. Therefore, an optimal silver content that inhibits bacterial colonization while maintaining osteoconductivity is crucial if silver were to be applied as a coating on parts intended for bone contact. This review summarizes the different methods used to apply silver coatings to arthroplasty components, with a focus on the amount and duration of silver release from the different coatings; the available experience with silver-coated implants that are in clinical use today; and future strategies to balance the effects of silver on bacteria and eukaryotic cells, and to develop silver-coated titanium components suitable for bone ingrowth. Cite this article: Bone Joint J 2021;103-B(3):423-429.


Asunto(s)
Antibacterianos/farmacología , Artroplastia , Materiales Biocompatibles Revestidos/farmacología , Prótesis e Implantes , Infecciones Relacionadas con Prótesis/prevención & control , Plata/farmacología , Humanos
5.
Molecules ; 26(4)2021 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-33672903

RESUMEN

Burkholderia pseudomallei is the causative pathogen of melioidosis and this bacterium is resistant to several antibiotics. Silver nanoparticles (AgNPs) are an interesting agent to develop to solve this bacterial resistance. Here, we characterize and assess the antimelioidosis activity of AgNPs against these pathogenic bacteria. AgNPs were characterized and displayed a maximum absorption band at 420 nm with a spherical shape, being well-monodispersed and having high stability in solution. The average size of AgNPs is 7.99 ± 1.46 nm. The antibacterial efficacy of AgNPs was evaluated by broth microdilution. The bactericidal effect of AgNPs was further assessed by time-kill kinetics assay. Moreover, the effect of AgNPs on the inhibition of the established biofilm was investigated by the crystal violet method. In parallel, a study of the resistance induction development of B. pseudomallei towards AgNPs with efflux pump inhibiting effect was performed. We first found that AgNPs had strong antibacterial activity against both susceptible and ceftazidime-resistant (CAZ-resistant) strains, as well as being efficiently active against B. pseudomallei CAZ-resistant strains with a fast-killing mode via a bactericidal effect within 30 min. These AgNPs did not only kill planktonic bacteria in broth conditions, but also in established biofilm. Our findings first documented that the resistance development was not induced in B. pseudomallei toward AgNPs in the 30th passage. We found that AgNPs still showed an effective efflux pump inhibiting effect against these bacteria after prolonged exposure to AgNPs at sublethal concentrations. Thus, AgNPs have valuable properties for being a potent antimicrobial agent to solve the antibiotic resistance problem in pathogens.


Asunto(s)
Proteínas Bacterianas/antagonistas & inhibidores , Burkholderia pseudomallei/fisiología , Melioidosis/tratamiento farmacológico , Melioidosis/microbiología , Nanopartículas del Metal/uso terapéutico , Plata/uso terapéutico , Taninos/uso terapéutico , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Proteínas Bacterianas/metabolismo , Burkholderia pseudomallei/efectos de los fármacos , Ceftazidima/farmacología , Ceftazidima/uso terapéutico , Farmacorresistencia Bacteriana/efectos de los fármacos , Dispersión Dinámica de Luz , Cinética , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Fenotipo , Plata/farmacología , Electricidad Estática , Taninos/farmacología
6.
Molecules ; 26(5)2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33668169

RESUMEN

A series of fifteen silver (I) quinoline complexes Q1-Q15 have been synthesized and studied for their biological activities. Q1-Q15 were synthesized from the reactions of quinolinyl Schiff base derivatives L1-L5 (obtained by condensing 2-quinolinecarboxaldehyde with various aniline derivatives) with AgNO3, AgClO4 and AgCF3SO3. Q1-Q15 were characterized by various spectroscopic techniques and the structures of [Ag(L1)2]NO3Q1, [Ag(L1)2]ClO4Q6, [Ag(L2)2]ClO4Q7, [Ag(L2)2]CF3SO3Q12 and [Ag(L4)2]CF3SO3Q14 were unequivocally determined by single crystal X-ray diffraction analysis. In vitro antimicrobial tests against Gram-positive and Gram-negative bacteria revealed the influence of structure and anion on the complexes' moderate to excellent antibacterial activity. In vitro antioxidant activities of the complexes showed their good radical scavenging activity in ferric reducing antioxidant power (FRAP). Complexes with the fluorine substituent or the thiophene or benzothiazole moieties are more potent with IC50 between 0.95 and 2.22 mg/mL than the standard used, ascorbic acid (2.68 mg/mL). The compounds showed a strong binding affinity with calf thymus-DNA via an intercalation mode and protein through a static quenching mechanism. Cytotoxicity activity was examined against three carcinoma cell lines (HELA, MDA-MB231, and SHSY5Y). [Ag(L2)2]ClO4Q7 with a benzothiazole moiety and [Ag(L4)2]ClO4Q9 with a methyl substituent had excellent cytotoxicity against HELA cells.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos/farmacología , Antioxidantes/farmacología , Complejos de Coordinación/farmacología , ADN/química , Antibacterianos/síntesis química , Antibacterianos/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Antioxidantes/síntesis química , Antioxidantes/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Ensayos de Selección de Medicamentos Antitumorales , Compuestos Férricos/antagonistas & inhibidores , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Oxidación-Reducción , Quinolinas/química , Quinolinas/farmacología , Bases de Schiff/química , Bases de Schiff/farmacología , Plata/química , Plata/farmacología
7.
Arch Oral Biol ; 125: 105101, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33676363

RESUMEN

OBJECTIVE: This study aimed to analyze the antimicrobial effects of lyophilized hydroalcoholic extract (HEScSeed and HEScFlower) and silver nanoparticles (AgNPs-HEScSeed and AgNPs-HEScFlower) of S. cumini seed and flower, and to characterize some compounds of these extracts and their NPs. DESIGN: Phytochemical screening was performed by GC-MS. Nanoparticles were characterized by UV-vis spectroscopy, energy-dispersive X-ray (EDX) spectrophotometry, scanning electron microscopy (SEM) and field emission gun (FEG), dynamic light scattering (DLS) and zeta potential (ZP). Antimicrobial susceptibility tests were analyzed by broth microdilution and agar diffusion methods. RESULTS: HEScSeed and HEScFlower showed 7 and 17 phytochemical compounds, respectively. AgNPs-plant extracts were reported as stable and with variable shapes and sizes. All studied species (A. naeslundii, C. albicans, F. nucleatum, S. aureus, S. epidermidis, S. mutans, S. oralis and V. dispar) were susceptible to extracts and AgNPs-plant extracts, with varying degrees of antimicrobial activities (extract: 648.4-5,187.5 µg/mL; AgNPs-plant: 31.2-2,000 µg/mL). CONCLUSION: The extracts of S. cumini seed and flower have antimicrobial action against pathogens of medical and dental interest, whose MIC and MMC are species-dependent. The AgNPs-HEScSeed and AgNPs-HEScFlower have different shapes, sizes, organic compounds, stability and electronegativity (capping), characteristics that contribute to their bacteriostatic and fungistatic effects, but at significantly lower concentrations than plant extracts.


Asunto(s)
Antiinfecciosos , Nanopartículas del Metal , Syzygium , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Flores , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología , Semillas , Plata/farmacología , Staphylococcus aureus
8.
Plant Physiol Biochem ; 162: 531-546, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33773229

RESUMEN

Trifolium pratense L. (red clover) is an important leguminous crop with great potential for Ag-contaminated environment remediation. Whereas, the molecular mechanisms of Ag tolerance in red clover are largely unknown. Red clover seedlings were used for physiological and transcriptomic investigation under 0, 20, 50, and 100 mg/L Ag+ stress in our research to reveal potential molecular resistance mechanism. Research showed that red clover possessed fairly strong Ag absorbance capacity, the Ag level reached 0.14 and 2.35 mg/g·FW in the leaves and roots under 100 mg/L AgNO3 stress condition. Root fresh weight, root dry weight, root water content, and photosynthetic pigments contents were significantly decreased with elevating AgNO3 concentration. Obvious withered plant tissue, microstructure disorder, and disrupted organelles were observed. In vitro evaluations (e.g., PI and DCFH-DA staining) represented that AgNO3 at high concentration (100 mg/L) exhibited obvious inhibition on cell viability, which was due possibly to the induction of reactive oxygen species (ROS) accumulation. A total of 44643 differentially expressed genes (DEGs) were identified under Ag stress, covering 27155 upregulated and 17488 downregulated genes. 12 stress-responsive DEGs was authenticated utilizing real-time quantitative PCR (qRT-PCR). Gene ontology (GO) analysis revealed that the DEGs were mostly related to metal ion binding (molecular function), nucleus (cellular component), and defense response (biological process). Involved DEGs in sequence-specific DNA binding transcription factor activity, response to various hormones (e.g., abscisic acid, IAA/Auxin, salicylic acid, and etc), calcium signal transduction, and protein ubiquitination were concluded to play crucial roles in Ag tolerance of red clover. On the other hand, Kyoto Encyclopedia of Genes and Genomes (KEGG) database annotated several stress responsive pathways such as plant-pathogen interaction, phenylpropanoid biosynthesis, ubiquitin mediated proteolysis, hormone signal transduction, and autophagy. Several down-regulated genes (e.g., RSF2, RCD1, DOX1, and etc) were identified indicating possible metabolic disturbance. Besides, protein-protein interaction network (PPI) identified several pivotal genes such as ribosomal proteins, TIR, and ZAT.


Asunto(s)
Fabaceae , Trifolium , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Iones , Plata/farmacología , Transcriptoma
9.
J Infect Public Health ; 14(3): 324-330, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33618277

RESUMEN

BACKGROUND: Streptococcus mutans are an oral pathogen that causes dental caries, endocarditis, and systemic dysfunctions, an alternative antibacterial solution from silver nanoparticles (AgNPs) are investigated. METHODS: AgNPs were synthesized using the ethnobotanical product gum Arabic. It influenced the nanoparticles with medicinal value through their role as capping, stabilizing, or surface-attached components. The biophysical characteristics of the synthesized AgNPs were studied using UV-vis spectrum, XRD, EDAX, SEM, and TEM tools. The AgNPs were spherical with the average size less than 10 nm. By using the well diffusion and microdilution techniques, the impact of synthesized AgNPs was tested against S. mutans isolates. RESULTS: The smaller the size, the greater the antibacterial and antiviral potential the particles exhibit. The biophysical characteristics of AgNPs the presence of phenols, alcohols, amides, sulfoxide, flavanoids, terpenoids and steroids. The AgNPs exhibited a good antibacterial action against the oral pathogen S. mutans. The synthesized NPs at a dose level of 200 µg/mL exhibited an inhibition zone with 18.30 ± 0.5 nm diameter. The synthesised nanoparticles inhibited the genes responsible for biofilm formation of S. mutans over host tooth and gums (gtfB, gtfc, gtfD) and virulent protective factors (comDE, brpA and smu 360) and survival promoter genes (gyrA and spaP, gbpB). CONCLUSION: The potent antibiotic action over S. mutans seen with the synthesized NPs, paves the way for the development of novel dental care products. Also, the small-sized NPs promote its applicability in COVID-19 pandemic containment.


Asunto(s)
Antibacterianos/farmacología , Caries Dental/tratamiento farmacológico , Endocarditis/tratamiento farmacológico , Nanopartículas del Metal , Plata/farmacología , Streptococcus mutans/efectos de los fármacos , Biopelículas , Goma Arábiga , Humanos
10.
Int J Nanomedicine ; 16: 1345-1360, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33633450

RESUMEN

Purpose: Despite the extensive development of antibacterial biomaterials, there are few reports on the effects of materials on the antibacterial ability of the immune system, and in particular of neutrophils. In this study, we observe differences between the in vivo and in vitro anti-infective efficacies of silver nanoparticles (AgNPs). The present study was designed to further explore the mechanism for this inconsistency using ex vivo models and in vitro experiments. Methods: AgNPs were synthesized using the polyol process and characterized by transmission electron microscopy and X-ray photoelectron spectroscopy. The antibacterial ability of AgNPs and neutrophils was tested by the spread-plate method. The infected air pouch model was prepared to detect the antimicrobial ability of AgNPs in vivo. Furthermore, blood-AgNPs-bacteria co-culture model and reactive oxygen species (ROS) measurement were used to evaluate the effect of AgNPs to neutrophil-mediated phagocytosis and ROS production. Results: The antibacterial experiments in vitro showed that AgNPs had superior antibacterial properties in cell compatible concentration. While, AgNPs had no significant antibacterial effect in vivo, and pathological section in AgNPs group indicated less neutrophil infiltration in inflammatory site than S. aureus group. Furthermore, AgNPs were found to reduce the phagocytosis of neutrophils and inhibit their ability to produce ROS and superoxide during ex vivo and in vitro experiments. Conclusion: This study selects AgNPs as the representative of inorganic nano-biomaterials and reveals the phenomenon and the mechanism underlying the significant AgNPs-induced inhibition of the antibacterial ability of neutrophils, and may have a certain enlightening effect on the development of biomaterials in the future. In the fabrication of antibacterial biomaterials, however, attention should be paid to both cell and immune system safety to make the antibacterial properties of the biomaterials and innate immune system complement each other and jointly promote the host's ability to resist the invasion of pathogenic microorganisms.


Asunto(s)
Antibacterianos/farmacología , Sistema Inmunológico/efectos de los fármacos , Inmunidad Innata/efectos de los fármacos , Nanopartículas del Metal/química , Neutrófilos/citología , Fagocitosis/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Plata/farmacología , Animales , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Humanos , Mediadores de Inflamación/metabolismo , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Neutrófilos/efectos de los fármacos , ARN/metabolismo , Ratas Sprague-Dawley , Staphylococcus aureus/efectos de los fármacos , Superóxidos/metabolismo
11.
Int J Nanomedicine ; 16: 851-865, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33574666

RESUMEN

Background: Ionizing radiation (IR) is commonly used in triple-negative breast cancer (TNBC) treatment regimens. However, off-target toxicity affecting normal tissue and grueling treatment regimens remain major limitations. Hyperthermia is one of the greatest IR sensitizers, but only if heat is administered simultaneously or immediately prior to ionizing radiation. Difficulty in co-localizing ionizing radiation (IR) in rapid succession with hyperthermia, and confining treatment to the tumor have hindered widespread clinical adoption of combined thermoradiation treatment. Metal nanoparticle-based approaches to IR sensitization and photothermal heat generation may aid in overcoming these issues and improve treatment specificity. Methods: We assessed the potential to selectively treat MDA-MB-231 TNBC cells without affecting non-malignant MCF-10A breast cells using a multimodal approach based upon combined photothermal therapy, IR sensitization, and specific cytotoxicity using triangular silver nanoparticles (TAgNPs) with peak absorbance in the near-infrared light (NIR) spectrum. Results: We found that TAgNP-mediated photothermal therapy and radiosensitization offer a high degree of specificity for treatment of TNBC without affecting non-malignant mammary epithelial cells. Discussion: If given at a high enough dose, IR, heat, or TAgNPs alone could be sufficient for tumor treatment. However, when the dose of one or all of these modalities increases, off-target effects also increase. The challenge lies in identifying the minimal doses of each individual treatment such that when combined they provide maximum selectivity for treatment of TNBC cells with minimum off-target effects on non-malignant breast cells. Our results provide proof of concept that this combination is highly selective for TNBC cells while sparing non-malignant mammary epithelial cells. This treatment would be particularly important for patients undergoing breast conservation therapy and for treatment of invasive tumor margins near the periphery where each individual treatment might be at a sub-therapeutic level.


Asunto(s)
Nanopartículas del Metal/uso terapéutico , Radiación Ionizante , Plata/uso terapéutico , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/radioterapia , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Carcinogénesis/efectos de los fármacos , Carcinogénesis/patología , Carcinogénesis/efectos de la radiación , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Terapia Combinada , Femenino , Humanos , Rayos Infrarrojos , Nanopartículas del Metal/ultraestructura , Fármacos Sensibilizantes a Radiaciones/farmacología , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Plata/farmacología , Neoplasias de la Mama Triple Negativas/patología
12.
Life Sci ; 272: 119262, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33639151

RESUMEN

The perpetual lack of advanced strategies to prevent aggressive breast cancer with multiple categories represents challenging scientific society problems. Reduced graphene oxide- can treat disease, which was recently investigated due to its ability to induce apoptosis-based death. This research tested the chemotherapeutics in vitro efficacy of reduced graphene oxide embedded with gold and silver nanoparticles toward drug-sensitive breast cancer cells (MCF-7) and their cytotoxicity. Synthesis of the Au-Ag/rGO-5FU nanocomposites has been conducted using a wet chemical approach with chitosan aid as a pore directing and capping agent. The particle structure and morphology well characterized using different systems. HR-TEM shows a narrow-sized distribution of less than 100 nm, which is proper for cell membranes and medical use. The physical combination of the nanocomposite and 5-FU drug has been conducted mechanically using wet chemistry. The Au/Ag/rGO-5FU material's high activity enables it to produce reactive oxygen radicals, which display a potential against MCF-7 cell lines. All the results, including those obtained via cytometry, use the combination of Au/Ag/rGO-5FU to show a more substantial anticancer influence and more drug stability than pure 5-FU.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Oro/farmacología , Grafito/farmacología , Plata/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Fluorouracilo/farmacología , Oro/química , Grafito/metabolismo , Humanos , Células MCF-7 , Nanopartículas del Metal/química , Nanopartículas del Metal/uso terapéutico , Nanocompuestos/química , Especies Reactivas de Oxígeno/metabolismo , Plata/química
13.
J Dent ; 106: 103589, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33524431

RESUMEN

OBJECTIVES: Denture soft liner is applied to relieve pain from candida-induced denture stomatitis and promote healing, but with shortage of antifungal activity and easily harbors fungi. To overcome this problem, the in-situ method was used to synthesize silver nanoparticles (AgNPs) in acrylic soft liner to obtain antifungal effects. METHODS: Acrylic soft-liner with various weight percentage of silver 2-ethylhexanoate (0%, 0.1 %, 0.2 %, 0.3 %) were prepared in 10 mm × 10 mm × 3 mm. After chemical polymerization, the diameter of AgNPs synthesized in situ and the degree of conversion of each group were measured. After 3, 7, and 14 days of storage in water, the antifungal rate (AFR) of in vitro direct contact antifungal assays and the antifungal test of non-cumulative extract solution were measured respectively. The release profiles of silver ions from the specimen within 14 days were also evaluated. RESULTS: Evenly distributed AgNPs (4.7 nm-5.3 nm) were observed, and the degree of conversion had no significant difference among these groups. The AFR increased as the silver concentration rose, while decreasing with the storage time. After 14 days of water storage, the AFR of 0.2 % and 0.3 % groups still reached 63.38 % and 75.51 %, respectively. The non-cumulative extract solution had no antifungal effect. CONCLUSIONS: Within the service life, the acrylic soft liner containing AgNPs synthesized in situ had effective control of Candida albicans through direct contact. CLINICAL SIGNIFICANCE: This study suggests that AgNPs synthesized in situ may be an effective strategy in modifying acrylic denture soft liner to treat and prevent denture stomatitis.


Asunto(s)
Alineadores Dentales , Nanopartículas del Metal , Antifúngicos/farmacología , Candida albicans , Dentaduras , Plata/farmacología
14.
Int J Mol Sci ; 22(2)2021 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-33467032

RESUMEN

Silver and its nanoparticles (AgNPs) have different faces, providing different applications. In recent years, the number of positive nanosilver applications has increased substantially. It has been proven that AgNPs inhibit the growth and survival of bacteria, including human and animal pathogens, as well as fungi, protozoa and arthropods. Silver nanoparticles are known from their antiviral and anti-cancer properties; however, they are also very popular in medical and pharmaceutical nanoengineering as carriers for precise delivery of therapeutic compounds, in the diagnostics of different diseases and in optics and chemistry, where they act as sensors, conductors and substrates for various syntheses. The activity of AgNPs has not been fully discovered; therefore, we need interdisciplinary research to fulfil this knowledge. New forms of products with silver will certainly find application in the future treatment of many complicated and difficult to treat diseases. There is still a lack of appropriate and precise legal condition regarding the circulation of nanomaterials and the rules governing their safety use. The relatively low toxicity, relative biocompatibility and selectivity of nanoparticle interaction combined with the unusual biological properties allow their use in animal production as well as in bioengineering and medicine. Despite a quite big knowledge on this topic, there is still a need to organize the data on AgNPs in relation to specific microorganisms such as bacteria, viruses or fungi. We decided to put this knowledge together and try to show positive and negative effects on prokaryotic and eukaryotic cells.


Asunto(s)
Antiinfecciosos/química , Enfermedades Transmisibles/tratamiento farmacológico , Nanopartículas del Metal/química , Plata/farmacología , Animales , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Biopelículas/efectos de los fármacos , Humanos , Nanopartículas del Metal/efectos adversos , Nanopartículas del Metal/uso terapéutico , Plata/química
15.
Carbohydr Polym ; 255: 117484, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33436244

RESUMEN

Wound dressing composed of chitosan, based crosslinked gelatin/ polyvinyl pyrrolidone, embedded silver nanoparticles were fabricated using solution casting method. The membrane was characterized by FTIR, SEM and TGA. Glutaraldehyde (0.5 %) was used for the crosslinking of membrane components and associated with 7-folds boosted mechanical performance, 28 % more hydrolytic stability, 3-folds thickness reduction and morphological roughness. Silver nanoparticles were characterized by UV-vis, XRD and TEM for an average size of 9.9 nm. The membrane with higher concentration of silver nanoparticles showed maximum antibacterial activity against human pathogenic bacteria; and the measured inhibition zones ranged from 1.5 to 3 cm. The activity of the particles ranged from severe to complete reduction in Penicillin, Erythromycin and Macrolide family's resistance genes expression such as ß-Lactamase, mecA and erm. This developed membrane can serve as promising and cost-effective system against severe diabetic and burn wound infections.


Asunto(s)
Antibacterianos/farmacología , Vendajes , Quitosano/química , Citrullus colocynthis/química , Gelatina/química , Povidona/química , Plata/farmacología , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/crecimiento & desarrollo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Farmacorresistencia Bacteriana Múltiple/genética , Eritromicina/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Humanos , Macrólidos/farmacología , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Metiltransferasas/genética , Metiltransferasas/metabolismo , Pruebas de Sensibilidad Microbiana , Proteínas de Unión a las Penicilinas/genética , Proteínas de Unión a las Penicilinas/metabolismo , Penicilinas/farmacología , Cultivo Primario de Células , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/crecimiento & desarrollo , Salmonella typhi/efectos de los fármacos , Salmonella typhi/crecimiento & desarrollo , Plata/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , beta-Lactamasas/genética , beta-Lactamasas/metabolismo
16.
J Dent ; 106: 103563, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33482245

RESUMEN

OBJECTIVES: To provide a suitable material capable of treating dentin hypersensitivity with simultaneous active antibacterial activity. METHODS: We developed silver-containing mesoporous bioglass (MBG-Ag) using the sol-gel technique, which loaded silver nanoparticles as promising bacteriostatic agents. The MBG-Ag with a powder-to-liquid ratio of 0.5 g: 0.01 mL were uniformly mixed with 20 %, 30 %, and 40 % phosphoric acid for 5, 10 and 20 min, respectively. Furthermore, we evaluated the occlusion efficiency, depth of penetration, and antibacterial activity of dentin specimens by simulating a Streptococcus mutans (S. mutans) infection on dentin. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) were used to characterize the powders and assess tubule occlusion. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the MBG-Ag against S. mutans were determined via time-killing curves and colony formation assays. RESULTS: The MIC ranged from 2.5 to 5 mg/mL, and the MBC ranged from 5 to 10 mg/mL. The highest dentinal tubule occlusion efficiency was over 90 %. The colony formation assay confirmed that 5 mg/mL MBG-Ag mixed with phosphoric acid reached the bactericidal concentration. CONCLUSION: The MBG-Ag 40PA achieved a good occlusion efficiency and deep apatite precipitation in a short time, implying its superiority in clinical applications. CLINICAL RELEVANCE: The MBG-Ag formed in this study is a promising candidate for the treatment of demineralized dentin and confers antibacterial effects on the remineralized dentin surface against S. mutans.


Asunto(s)
Nanopartículas del Metal , Plata , Antibacterianos/farmacología , Cerámica , Dentina , Plata/farmacología , Espectroscopía Infrarroja por Transformada de Fourier
17.
Int J Nanomedicine ; 16: 481-492, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33500618

RESUMEN

Background: Dihydromyricetin (DMY), a natural flavonoid, has reportedly antibacterial, antioxidant, anticancer and other properties. In the present study, DMY was used as a reducing agent and stabilizer to synthesize silver nanoparticles (AgNPs), and the optimal conditions for its synthesis were studied. The DMY-AgNPs were investigated for their DPPH scavenging properties and their potential against human pathogenic and food-borne bacteria viz. Escherichia coli (E. coli), and Salmonella. In addition, DMY-AgNPs also showed excellent inhibitory effects on cancer Hela, HepG2 and MDA-MB-231 cell lines. Methods: The dihydromyricetin-mediated AgNPs (DMY-AgNPs) were characterized by ultraviolet-visible spectrophotometer (UV-Vis spectra), scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and X-ray powder diffraction (XRD). Antioxidant activity of DMY-AgNPs was determined by 1.1-diphenyl-2-picrylhydrazyl (DPPH) scavenging. The antibacterial activity was determined by 96-well plate (AGAR) gradient dilution, while anticancer potential was determined by MTT assay. Results: The results showed that the dispersion of AgNPs had the maximum UV-visible absorption at about 410 nm. The synthesized nanoparticles were almost spherical. FTIR was used to identify functional groups that may lead to the transformation of metal ions into nanoparticles. The results showed that the prepared AgNPs were coated with biological molecules in the extraction solution. The biosynthesized DMY-AgNPs exhibited good antioxidant properties, at various concentrations (0.01-0.1mg/mL), the free radical scavenging rate was about 56-92%. Furthermore, DMY-AgNPs possessed good antibacterial properties against Escherichia coli (E. coli), and Salmonella at room temperature. The minimum inhibitory concentrations (MIC) were 10-6 g/L, and 10-4 g/L, respectively. The bioactivity of DMY-mediated AgNPs was studied using MTT assay against Hela, HepG2 and MDA-MB-231 cancer cell lines, and all showed good inhibitory effects. Conclusion: The present study provides a green approach for the synthesis of DMY-AgNPs which exhibited stronger antioxidant, antibacterial and anticancer properties compared to the dihydromyricetin. DMY-AgNPs can serve as an economical, efficient, and effective antimicrobial material for its applications in food and pharmaceutical fields.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos/farmacología , Antioxidantes/farmacología , Flavonoles/farmacología , Nanopartículas del Metal/química , Plata/farmacología , Bacterias/efectos de los fármacos , Línea Celular Tumoral , Escherichia coli/efectos de los fármacos , Humanos , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Espectrofotometría Ultravioleta , Difracción de Rayos X
18.
Int J Nanomedicine ; 16: 15-29, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33447027

RESUMEN

Purpose: The present study investigates the phytosynthesis of silver nanoparticles (AgNPs) using Perilla frutescens leaf extract, which acts as a reducing agent for the conversion of silver ions (Ag+) into AgNPs. P. frutescens leaf synthesized AgNPs (PF@AgNPs) were evaluated for biomedical properties including antibacterial, antioxidant and anticancer activities. Materials and Methods: PF@AgNPs were synthesized using P. frutescens leaf extract and silver nitrate solution. The morphology and physical properties of PF@AgNPs were studied by spectroscopic techniques including, UV-Vis, FTIR, TEM, XRD, DLS, and TGA. Antibacterial activity of PF@AgNPs was evaluated by disk diffusion assay. Antioxidant activity of PF@AgNPs was checked by 2.2-diphenyl-1-picrylhydrazyl (DPPH), and 2.2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical scavenging assays. Anticancer activity of PF@AgNPs was checked by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Cytotoxic effects of PF@AgNPs on most susceptible cancer cell lines were observed by phase contrast microscopy. Results: PF@AgNPs showed surface plasmon resonance peak at 461 nm. XRD pattern showed that the PF@AgNPs were face-centered cubic crystals with a mean size of 25.71 nm. TEM analysis revealed the different shapes (spherical, rhombic, triangle, and rod) of PF@AgNPs. Zeta potential value (-25.83 mV) indicated that PF@AgNPs were long-term stable and not agglomerated. A low polydispersity index value (0.389) indicated the monodispersity of PF@AgNPs. TGA revealed the high thermal stability of PF@AgNPs. PF@AgNPs exhibited maximum inhibition against Escherichia coli, followed by Bacillus subtilis and Staphylococcus aureus. PF@AgNPs showed maximum inhibition of 68.02 and 62.93% against DPPH and ABTS-free radicals, respectively. PF@AgNPs showed significant anticancer activity against human colon cancer (COLO205) and prostate adenocarcinoma (LNCaP). PF@AgNPs exhibited apoptotic effects on LNCaP cells including cell shrinkage, membrane blebbing, chromatin condensation, fragmentation of nuclei, and formation of apoptotic bodies. Conclusion: The present study reports the successful synthesis of PF@AgNPs using P. frutescens leaf extract. The synthesized PF@AgNPs are FCC crystals, monodispersed, long-term stable, and non-agglomerated. The observed antibacterial, antioxidant, and anticancer activities demonstrate the potential biomedical applications of PF@AgNPs.


Asunto(s)
Antibacterianos/farmacología , Antineoplásicos/farmacología , Antioxidantes/farmacología , Nanopartículas del Metal/química , Perilla frutescens/química , Extractos Vegetales/química , Hojas de la Planta/química , Plata/farmacología , Bacillus subtilis/efectos de los fármacos , Compuestos de Bifenilo/química , Línea Celular Tumoral , Color , Dispersión Dinámica de Luz , Escherichia coli/efectos de los fármacos , Depuradores de Radicales Libres/farmacología , Humanos , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Picratos/química , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Electricidad Estática , Termogravimetría , Difracción de Rayos X
19.
Int J Biol Macromol ; 173: 203-210, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33484799

RESUMEN

Nonwoven fabrics containing silver nanoparticles (AgNPs) are widely utilized to assist management of infected wounds and those at risk of infection. However, such materials have varied responses due to their chemical nature. Herein we investigated the correlation between the concentration of AgNPs taken up by nonwoven viscose material and antibacterial activity in a simulated wound fluid model against two bacterial models (i.e., Escherichia coli and Staphylococcus aureus). Thereafter, the developed nonwoven viscose containing AgNPs were independently coated with two polyacid carbohydrate polymers (i.e., carboxymethyl chitosan (CMCs), alginate (ALG)), and gelatin (GEL) protein in order to study their influence on the physical and biological attributes in vitro and in vivo. Intensive characterizations were utilized to monitor the physicochemical features of the developed nonwoven viscose. The results demonstrated that higher concentrations of AgNPs were taken up by viscose fabric whilewhile increasing AgNPs in the colloidal solution during padding process. Overall, the treated nonwoven fabric with and without polymers' coatings showed remarkable antibacterial activity against two bacterial models in vitro. As well as they achieved high and speed wound recovery in rats which was almost similar to commercial dermazin treatment. Therefore, it validates excellent nonwoven dressing clinically relevant to the wound type and condition.


Asunto(s)
Quemaduras Químicas/tratamiento farmacológico , Infecciones por Escherichia coli/tratamiento farmacológico , Nanopartículas del Metal/química , Plata/farmacología , Infecciones Estafilocócicas/tratamiento farmacológico , Cicatrización de Heridas/efectos de los fármacos , Alginatos/química , Animales , Antibacterianos/química , Antibacterianos/farmacología , Vendajes , Quemaduras Químicas/microbiología , Carboximetilcelulosa de Sodio/química , Quitosano/análogos & derivados , Quitosano/química , Preparaciones de Acción Retardada/química , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Infecciones por Escherichia coli/microbiología , Gelatina/química , Nanopartículas del Metal/ultraestructura , Ratas , Plata/química , Piel/efectos de los fármacos , Piel/microbiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Cicatrización de Heridas/fisiología
20.
Carbohydr Polym ; 252: 117156, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33183607

RESUMEN

A new natural formulation composed of CMC and various contents of CNC immobilized AgNPs (CNC@AgNPs) was developed for paper coating. The mechanical strength, water vapor and air barrier properties, and antibacterial activities of CMC/CNC@AgNPs coated paper improved with the increasing content of CNC@AgNPs. CMC/CNC@AgNPs7 % coated paper exhibited 1.26 times increase in tensile strength, 45.4 % decrease in WVP, 93.3 % reduction in air permeability as well as the best antibacterial activities against E.coli and S.aureus compared with uncoated paper. Moreover, the cumulative release rate of AgNPs from coated paper significantly reduced due to the immobilization effect of CNC on AgNPs. Furthermore, CMC/CNC@AgNPs coated paper was used to package strawberries under ambient conditions. The results showed that coated paper could maintain better strawberries quality compared with unpackaged strawberries and extend the shelf-life of strawberries to 7 days. Therefore, the prepared CMC/CNC@AgNPs coated paper will have a great application prospect in the food packaging.


Asunto(s)
Antibacterianos/farmacología , Carboximetilcelulosa de Sodio/química , Embalaje de Alimentos , Nanopartículas del Metal/química , Nanocompuestos/química , Plata/farmacología , Escherichia coli/efectos de los fármacos , Permeabilidad , Staphylococcus aureus/efectos de los fármacos , Vapor , Resistencia a la Tracción
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