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Advances in Wound Care Oct 2023Cerium nitrate (CeN) plus silver sulfadiazine (SSD) cream has been used for 40-plus years to manage burns. CeN produces a hardened eschar believed to resist bacterial...
Cerium nitrate (CeN) plus silver sulfadiazine (SSD) cream has been used for 40-plus years to manage burns. CeN produces a hardened eschar believed to resist bacterial colonization/infection. To evaluate this potential mechanism, we treated skin models or with CeN and measured mechanical properties of the models and bacterial virulence, respectively. We treated three-dimensional-collagen matrix and -burned porcine skin with CeN and evaluated stiffness and penetration. In addition, we treated with CeN and evaluated the bacteria's motility, skin model penetration, susceptibility to be phagocytized by the human monocytic cell line THP-1, and ability to stimulate this cell line to produce cytokines. CeN treatment of skin models stiffened them and made them resistant to penetration. Inversely, CeN treatment of reduced their motility, penetration through skin models (-burned porcine skin), and ability to stimulate cytokine production (tumor necrosis factor-α [TNF-α] and interleukin 8 [IL-8]) by THP-1 cells. In addition, CeN-treated was more readily phagocytized by THP-1 cells. Finally, inoculated on CeN-treated -burned porcine skin was more susceptible to killing by a silver dressing. skin models offer a platform for screening drugs that interfere with bacterial penetration into wounded tissue. CeN treatment reduced virulence, altered the mechanical properties of -burned porcine skin and collagen matrix, retarded penetration of through the skin models, and resulted in increased vulnerability of to killing by antimicrobial wound dressings. These data support the use of CeN in burn management.
Topics: Humans; Animals; Swine; Pseudomonas aeruginosa; Virulence; Silver Sulfadiazine; Skin; Bacterial Infections; Burns
PubMed: 36394961
DOI: 10.1089/wound.2022.0026 -
International Journal of Clinical... Aug 2023The ability of the () to form biofilms is not only crucial in the initiation of early childhood caries (ECC) but is also a challenge to its treatment. The current...
A Comparison of Antimicrobial Efficacy of Silver-based Preventive Restorations (Silver Nitrate, Silver Diamine Fluoride, and Silver Nanoparticles) against Monospecies Biofilm Model.
AIM
The ability of the () to form biofilms is not only crucial in the initiation of early childhood caries (ECC) but is also a challenge to its treatment. The current management protocols focus on remineralization and use of antimicrobial formulations which penetrate biofilms, control their formation, and decrease the incidence of caries in children. The paradigm shift toward preventive protocols and increasing antibiotic resistance rekindled the use of silver as a promising antibacterial agent. To gain further insight into the therapeutic potential, aim of the present study was to compare the antibacterial efficacy of silver-based preventive restorations [silver nitrate (AgNO), silver diamine fluoride (SDF), and silver nanoparticles (AgNPs)] against species.
MATERIALS AND METHODS
Using an monospecies biofilm model of ; the antimicrobial efficacy of three treatment groups (SDF, AgNO, and AgNPs) was evaluated.
RESULTS
There was a significant difference between the negative control and three treatment groups (SDF, AgNO, and AgNPs). The results showed that the mean diameter of inhibition zones obtained in biofilms treated with AgNPs was 40.3 ± 0.25 mm which was greater than both SDF (37.7 ± 0.18 mm) and AgNO (36.26 ± 0.18 mm).
CONCLUSION
The study concluded that the number of viable bacteria was significantly reduced by all three medicaments ( < 0.05). However, AgNPs showed the highest antimicrobial activity in comparison to SDF and AgNO against biofilm.
CLINICAL SIGNIFICANCE
The present study thus supports that AgNPs are a promising preventive anticaries agent due to their better antibacterial activity in comparison to other silver-based preventive restorations and can be effectively used as an alternative to SDF or AgNO for the noninvasive treatment of ECC in the young.
HOW TO CITE THIS ARTICLE
Sharma P, Dhawan P, Rajpal SK, A Comparison of Antimicrobial Efficacy of Silver-based Preventive Restorations (Silver Nitrate, Silver Diamine Fluoride, and Silver Nanoparticles) against Monospecies Biofilm Model. Int J Clin Pediatr Dent 2023;16(S-1):S13-S19.
PubMed: 37663210
DOI: 10.5005/jp-journals-10005-2575 -
Heliyon Oct 2023In this study, the chemical reduction method was applied to synthesize silver nanoparticles used to prepare conductive inks. The two variables of polyvinylpyrrolidone...
In this study, the chemical reduction method was applied to synthesize silver nanoparticles used to prepare conductive inks. The two variables of polyvinylpyrrolidone (PVP)- mole in the 0.01-0.03 mol range and hydrazine reducing mole in the 0.1-0.5 mol range, along with constants such as precursor mole (silver nitrate), complexing mole (ethylene diamine) and solvent mole (water), were used. Nine random samples proposed by the Design Expert software were examined and studied. X-ray diffraction (XRD) patterns, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and dynamic light scattering (DLS) were then used to characterize and evaluate the synthesized nanoparticles. According to the results obtained by XRD, FE-SEM and TEM analyses, the sample with 0.025 mol and 0.3 mol PVP had the minimum size of silver nanoparticles, which was around 20 nm, so it was chosen as the optimal sample for further research. The conductive ink was also prepared with the optimal sample of silver nanoparticles in 40% by weight and then characterized and evaluated by applying ultraviolet-visible (UV-Vis), simultaneous thermal analysis (STA), FE-SEM and electrical conductivity analysis. Finally, conductive ink was applied to polyethylene terephthalate (PET) and acrylonitrile butadiene styrene (ABS) substrates. The surface electrical resistance of conductive ink on PET and ABS substrates was then measured at about 6.4 Ω and 2.2 Ω, respectively.
PubMed: 37822640
DOI: 10.1016/j.heliyon.2023.e20548 -
Polymers Sep 2023The work was devoted to the development of technology for applying metal coatings to the surface of polypropylene products. At the same time, the main stages of the...
The work was devoted to the development of technology for applying metal coatings to the surface of polypropylene products. At the same time, the main stages of the technology were carried out using the influence of electromagnetic waves of light radiation. So, to obtain an electrically conductive silver layer, after mechanical treatment, etching and activation, the polymer was immersed for several minutes in a solution containing 10-20 g/L of silver nitrate and equivalent amounts of ascorbic acid, and a thin layer of solution was obtained on the surface of the polymer. A sample with such a sorption film was exposed to electromagnetic waves of light radiation at a flux density of 700-1100 W/m. The small thickness of the sorption film facilitated the penetration of these waves directly onto the polymer surface and ensured the photochemical process of silver reduction with the formation of active centers. At the same time, electromagnetic waves acting on ascorbic acid transferred it to an excited state. As a result, the chemical reduction of silver in the space between the active centers became possible. In this case, the film obtained within 15-20 min had the necessary electrical conductivity. The suitability of these films for galvanic metallization of the polymer surface was shown.
PubMed: 37765541
DOI: 10.3390/polym15183687 -
International Journal of Molecular... May 2024Melanoma, arguably the deadliest form of skin cancer, is responsible for the majority of skin-cancer-related fatalities. Innovative strategies concentrate on new...
Melanoma, arguably the deadliest form of skin cancer, is responsible for the majority of skin-cancer-related fatalities. Innovative strategies concentrate on new therapies that avoid the undesirable effects of pharmacological or medical treatment. This article discusses the chemical structures of [(MTZ)AgNO], [(MTZ)Ag]SO, [Ag(MCZ)NO], [Ag(MCZ)BF], [Ag(MCZ)SbF] and [Ag(MCZ)ClO] (MTZ-metronidazole; MCZ-miconazole) silver(I) compounds and the possible relationship between the molecules and their cytostatic activity against melanoma cells. Molecular Hirshfeld surface analysis and computational methods were used to examine the possible association between the structure and anticancer activity of the silver(I) complexes and compare the cytotoxicity of the silver(I) complexes of metronidazole and miconazole with that of silver(I) nitrate, cisplatin, metronidazole and miconazole complexes against A375 and BJ cells. Additionally, these preliminary biological studies found the greatest IC values against the A375 line were demonstrated by [Ag(MCZ)NO] and [(MTZ)AgNO]. The compound [(MTZ)AgNO] was three-fold more toxic to the A375 cells than the reference (cisplatin) and 15 times more cytotoxic against the A375 cells than the normal BJ cells. Complexes of metronidazole with Ag(I) are considered biocompatible at a concentration below 50 µmol/L.
Topics: Humans; Melanoma; Miconazole; Silver; Antineoplastic Agents; Metronidazole; Cell Line, Tumor; Coordination Complexes; Cell Survival; Skin Neoplasms
PubMed: 38791121
DOI: 10.3390/ijms25105081 -
International Journal of Nanomedicine 2023The biological synthesis of nanoparticles (NPs) has become a new methodology for the eco-friendly production of NPs with high scalability and biocompatibility....
PURPOSE
The biological synthesis of nanoparticles (NPs) has become a new methodology for the eco-friendly production of NPs with high scalability and biocompatibility. Cyanobacteria are one of the most widespread microorganisms on Earth and have been proven to be successful biofactories for synthesizing NPs. It is challenging to discover new microalgae with the potential to synthesize NPs of small size with high stability.
METHODS
Lukesova 2/91 was isolated, purified, and identified morphologically and genetically using microscopy and DNA sequencing. Volatile biomolecules in aqueous algal extracts were assessed using gas chromatography-mass spectroscopy (GC-MS).
RESULTS
Data showed that the main biomolecules were fatty acids and their esters, followed by secondary metabolites. Algal extract was used to convert silver nitrate (AgNO) into silver NPs under various optimized parameters. 1 mM of AgNO, 1:1 (V/V ratio of algal extract to AgNO), 25 °C, under light illumination, for 24 h, at pH 7.4 were the optimum conditions for NP production (Nos@AgNPs). Nos@AgNPs were characterized using UV-VIS spectroscopy, FTIR, TEM, SEM, EDx, mapping, and a Zetasizer. The wavelength of Nos@AgNPs was 401.4 nm and their shapes were cubic to oval, with an average diameter of 11.8 ± 0.5 nm. FTIR spectroscopy revealed that proteins/polysaccharides could be the main reductants, whereas these molecules and/or fatty acids could be stabilizers for NP synthesis. Nos@AgNPs (86.15%) was silver and had a hydrodynamic diameter of 10.7 nm with a potential charge of -19.7 mV. Antiproliferative and antimicrobial activities of Nos@AgNPs were evaluated. Nos@AgNPs exhibited significant inhibitory activity against lung, colon, and breast cancer cells and considerable biocidal activity against , and .
CONCLUSION
Lukesova 2/91 is an excellent source for the biofabrication of small and stable AgNPs with potent inhibitory effects against cancer and bacterial cells.
Topics: Anti-Bacterial Agents; Metal Nanoparticles; Nostoc muscorum; Plant Extracts; Silver; Fatty Acids
PubMed: 37818229
DOI: 10.2147/IJN.S420312 -
Scientific Reports Jul 2023Lithium niobite (LiNbO) nanostructure were successfully synthesized by chemical bath deposition method (CBD) and then decorated with silver nitrate (AgNO) through UV...
Lithium niobite (LiNbO) nanostructure were successfully synthesized by chemical bath deposition method (CBD) and then decorated with silver nitrate (AgNO) through UV activation method at different immersion durations (5, 15, 25, 35, and 45 s). The silver nanoparticles (AgNPs) effects on the optical and structural properties were studied and analyzed using various scientific devices and technique. X-ray diffraction (XRD) results showed that all the samples have a hexagonal structure with a maximum diffraction peak at the (012), and the existence of silver atoms could be recognized at 2θ = 38.2° which corresponds to the (111) diffraction plane. The optical absorption of nanocomposites depicted the presence of plasma peak related to silver (Ag) at 350 nm. The estimated energy gap from the optical absorption revealed a reduction in the Eg value from (3.97 eV) to (3.59 eV) with the presence of Ag atom. The Photolumincence (PL) peaks were observed at around 355 nm for pure LiNbO/Si and 358, 360, 363, 371, 476 nm for different immersion durations respectively, in the visible region of the electromagnetic spectrum. The scanning electron microscopy (SEM) study illustrated that with increasing the immersion time, especially at 45 s, a change in the particle morphology was observed (LiNbO NRs structure). Atomic force microscopy (AFM) displayed that the surface roughness decreases from 80.71 nm for pure sample to 23.02 nm for the decorated sample as the immersion time is increased. FT-IR manifested a noticeable increase in the intensity of the peaks of samples decorated with AgNPs. Raman spectroscopy elucidated that the peaks shifted to higher intensity due to the plasmonic effect of Ag nanoparticles. Ag-LiNbO/Si heterojunction nano-devices were fabricated successfully and enhanced the optoelectronic properties in comparison with the pure LiNbO/Si heterojunction device.
PubMed: 37460581
DOI: 10.1038/s41598-023-38363-8 -
JBMR Plus Dec 2023Type 2 diabetes mellitus (T2DM) increases risk of fractures due to bone microstructural and material deficits, though the mechanisms remain unclear. Preclinical models...
Type 2 diabetes mellitus (T2DM) increases risk of fractures due to bone microstructural and material deficits, though the mechanisms remain unclear. Preclinical models mimicking diabetic bone disease are required to further understand its pathogenesis. The TALLYHO/JngJ (TH) mouse is a polygenic model recapitulating adolescent-onset T2DM in humans. Due to incomplete penetrance of the phenotype ~25% of male TH mice never develop hyperglycemia, providing a strain-matched nondiabetic control. We performed a comprehensive characterization of the metabolic and skeletal phenotype of diabetic TH mice and compared them to either their nondiabetic TH controls or the recommended SWR/J controls to evaluate their suitability to study diabetic bone disease in humans. Compared to both controls, male TH mice with T2DM exhibited higher blood glucose levels, weight along with impaired glucose tolerance and insulin sensitivity. TH mice with/without T2DM displayed higher cortical bone parameters and lower trabecular bone parameters in the femurs and vertebrae compared to SWR/J. The mechanical properties remained unchanged for all three groups except for a low-energy failure in TH mice with T2DM only compared to SWR/J. Histomorphometry analyses only revealed higher number of osteoclasts and osteocytes for SWR/J compared to both groups of TH. Bone turnover markers procollagen type 1 N-terminal propeptide (P1NP) and tartrate-resistant acid phosphatase (TRAP) were low for both groups of TH mice compared to SWR/J. Silver nitrate staining of the femurs revealed low number of osteocyte lacunar and dendrites in TH mice with T2DM. Three-dimensional assessment showed reduced lacunar parameters in trabecular and cortical bone. Notably, osteocyte morphology changed in TH mice with T2DM compared to SWR/J. In summary, our study highlights the utility of the TH mouse to study T2DM, but not necessarily T2DM-induced bone disease, as there were no differences in bone strength and bone cell parameters between diabetic and non-diabetic TH mice. © 2023 The Authors. published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
PubMed: 38130754
DOI: 10.1002/jbm4.10843 -
Environmental Science and Pollution... Nov 2023Owing to the unique physicochemical properties and the low manufacturing costs, silver nanoparticles (AgNPs) have gained growing interest and their application has...
Owing to the unique physicochemical properties and the low manufacturing costs, silver nanoparticles (AgNPs) have gained growing interest and their application has expanded considerably in industrial and agricultural sectors. The large-scale production of these nanoparticles inevitably entails their direct or indirect release into the environment, raising some concerns about their hazardous aspects. Callus culture represents an important tool in toxicological studies to evaluate the impact of nanomaterials on plants and their potential environmental risk. In this study, we investigated the chronic phytotoxic effects of different concentrations of novel bifunctionalized silver nanoparticles (AgNPs-Cit-L-Cys) and silver nitrate (AgNO) on callus culture of Populus nigra L., a pioneer tree species in the riparian ecosystem. Our results showed that AgNPs-Cit-L-Cys were more toxic on poplar calli compared to AgNO, especially at low concentration (2.5 mg/L), leading to a significant reduction in biomass production, accompanied by a decrease in protein content, a significant increase in both lipid peroxidation level, ascorbate peroxidase (APX), and catalase (CAT) enzymatic activities. In addition, these findings suggested that the harmful activity of AgNPs-Cit-L-Cys might be correlated with their physicochemical properties and not solely attributed to the released Ag ions and confirmed that AgNPs-Cit-L-Cys phytoxicity is associated to oxidative stress.
Topics: Silver Nitrate; Metal Nanoparticles; Populus; Ecosystem; Silver
PubMed: 37907823
DOI: 10.1007/s11356-023-30690-7 -
Microbiology Spectrum Aug 2023The constant, ever-increasing antibiotic resistance crisis leads to the announcement of "urgent, novel antibiotics needed" by the World Health Organization. Our previous...
The constant, ever-increasing antibiotic resistance crisis leads to the announcement of "urgent, novel antibiotics needed" by the World Health Organization. Our previous works showed a promising synergistic antibacterial activity of silver nitrate with potassium tellurite out of thousands of other metal/metalloid-based antibacterial combinations. The silver-tellurite combined treatment not only is more effective than common antibiotics but also prevents bacterial recovery, decreases the risk of future resistance chance, and decreases the effective concentrations. We demonstrate that the silver-tellurite combination is effective against clinical isolates. Further, this study was conducted to address knowledge gaps in the available data on the antibacterial mechanism of both silver and tellurite, as well as to give insight into how the mixture provides synergism as a combination. Here, we defined the differentially expressed gene profile of Pseudomonas aeruginosa under silver, tellurite, and silver-tellurite combination stress using an RNA sequencing approach to examine the global transcriptional changes in the challenged cultures grown in simulated wound fluid. The study was complemented with metabolomics and biochemistry assays. Both metal ions mainly affected four cellular processes, including sulfur homeostasis, reactive oxygen species response, energy pathways, and the bacterial cell membrane (for silver). Using a Caenorhabditis elegans animal model we showed silver-tellurite has reduced toxicity over individual metal/metalloid salts and provides increased antioxidant properties to the host. This work demonstrates that the addition of tellurite would improve the efficacy of silver in biomedical applications. Metals and/or metalloids could represent antimicrobial alternatives for industrial and clinical applications (e.g., surface coatings, livestock, and topical infection control) because of their great properties, such as good stability and long half-life. Silver is the most common antimicrobial metal, but resistance prevalence is high, and it can be toxic to the host above a certain concentration. We found that a silver-tellurite composition has antibacterial synergistic effect and that the combination is beneficial to the host. So, the efficacy and application of silver could increase by adding tellurite in the recommended concentration(s). We used different methods to evaluate the mechanism for how this combination can be so incredibly synergistic, leading to efficacy against antibiotic- and silver-resistant isolates. Our two main findings are that (i) both silver and tellurite mostly target the same pathways and (ii) the coapplication of silver with tellurite tends not to target new pathways but targets the same pathways with an amplified change.
Topics: Animals; Silver Nitrate; Pseudomonas aeruginosa; Anti-Bacterial Agents; Anti-Infective Agents; Metalloids; Microbial Sensitivity Tests
PubMed: 37409940
DOI: 10.1128/spectrum.00628-23