AgNPs Group Research Articles

The potential curative role of Avena sativa extract against oxidative stress, DNA damage and apoptosis induced by acute hepatotoxicity of silver nanoparticles in rats.

Silver nanoparticles (Ag NPs or nanosilver) have pulled in expanding interest because of their novel physical, substance, and organic properties contrasted with their full scale scaled partners. The goal of this study was to investigate if Avena sativa (AVS) extract could ameliorate Ag NPs toxicity-induced alterations in liver structure and function, DNA damage, apoptosis, and oxidative stress. Twenty adult male rats were assigned randomly to four groups: control, AVS (intragastrically, 5g/Kg body weight/day) for 2 weeks, Ag NPs (400 mg/kg body weight/day) for 1 week as acute toxicity and Ag NPs + AVS (same therapy of Ag NPs as acute toxicity with AVS). This study demonstrated a statistical significant increase in serum levels of liver function tests (AST, ALT, ALP and globulin), liver DNA damage, apoptotic P53 and Malondialdehyde after Ag NPs administration when compared to control group. Conversely, statistical significant decreases were detected in serum albumin, total proteins, liver reduced glutathione, catalase, superoxide dismutase, glutathione S-transferase and anti-apoptotic Bcl2 in Ag NPs group as compared to control group. Interestingly, treatment of Ag NPs with AVS (Ag Nps + AVS) was associated with significant improvements of the studied parameters, liver structure and functions. Avena sativa (AVS) extract could scavenge free radicals producing beneficial effects against acute Ag NPs hepatotoxicity in rats induced through activation of oxidative stress and apoptosis.

Silver Nanofunctionalized Stent after Radiofrequency Ablation Suppresses Tissue Hyperplasia and Bacterial Growth.

Intraductal radiofrequency (RF) ablation combined with placement of a self-expandable metal stent (SEMS) for malignant biliary obstruction has risks such as stent- and heat-induced biliary sludge and restenosis. Here, we investigated the efficacy of a silver nanoparticles (AgNPs)-coated SEMS to inhibit tissue hyperplasia and bacterial growth caused by RF ablation with stent placement in the rabbit bile duct. The release behavior and antibacterial effects of AgNPs-coated SEMSs were evaluated. Then, SEMSs were successfully placed in all rabbits immediately after RF ablation. Ag ions were rapidly released at the beginning and then showed a gradual release behavior. The AgNPs-coated SEMS significantly inhibited bacterial activity compared to the uncoated SEMS (p < 0.05). Cholangiography and histological examination confirmed that the level of tissue hyperplasia was significantly lower in the AgNPs group than in the control group (all p < 0.05). Immunohistochemistry analyses revealed that TUNEL-, HSP 70-, and α-SMA-positive areas were significantly lower in the AgNPs group than in the control group (all p < 0.05). Intraductal RF ablation combined with nanofunctionalized stent placement represents a promising new approach for suppressing thermal damage as well as stent-induced tissue hyperplasia and bacterial growth.

Biochemical, molecular and cytological impacts of alpha-lipoic acid and Ginkgo biloba in ameliorating testicular dysfunctions induced by silver nanoparticles in rats.

Silver nanoparticles (AgNPs) are commonly utilized in medicine. However, they have negative effects on the majority of organs, including the reproductive system. AgNPs were reported to be able to reach the testicular tissues due to their nano size, which allows them to pass through blood-testicular barriers. The goal of this study was to see if alpha-lipoic acid (LA) or Ginkgo biloba (GB) might protect adult rat testes after intraperitoneal injection of AgNPs. Forty male healthy adult Wister albino rats were randomly assigned to four groups: control, AgNPs-intoxicated group intraperitoneally injected AgNPs 50mg/kg b.w, 3 times a week; LA + AgNPs group intoxicated with AgNPs and orally gavaged with 100mg LA/kg b.w; and GB + AgNPs group injected with AgNPs and orally given GB extract 120mg/kg b.w for 30 consecutive days. Biochemical changes (testosterone, ACP, and prostatic acid phosphatase), oxidative indices, mRNA expression of proapoptotic (BAX) and anti-apoptotic (BCL-2) biomarkers, histological, and immunohistochemical changes in testicular tissues were investigated. Significant decrease in serum testosterone level and elevation in ACP and PACP enzyme activity in AgNPs-treated rats. As well, there were lowering in tGSH, GSH GR, GPx, and elevation in MDA and GSSG values. AgNPs-exposed rats expressed downregulation of testicular thirodexin-1 (Txn-1), transforming growth factor-1β (TGF-1β), anti-apoptotic (BCL-2), and upregulaion of proapoptotic biomarkers (BAX) mRNA expressions. Strong positive action to BAX and lowering the action of Ki-67 antibody were observed. Because of their antioxidant, anti-inflammatory, and anti-apoptotic properties, cotreatment with LA or GB could be beneficial in reducing the harmful effects of AgNPs on the testicles.

Attenuating Effect of Vitamin E against Silver Nano Particles Toxicity in Submandibular Salivary Glands.

Silver nanoparticles (AgNPs) are extensively used in many industries due to their superior antimicrobial properties. However, it is evident from many studies that AgNPs has cytotoxic potential through its effect on excessive formation of reactive oxygen species (ROS). The aim of this study was to examine the toxic effect of AgNPs on the submandibular salivary glands and the attenuating effect of vitamin E, as a natural antioxidant, against this toxicity. Thirty Albino rats were divided into 3 groups (n = 10): control group, AgNPs group receiving 2 mg/kg daily for 28 days, and AgNPs and vitamin E group receiving AgNPs the same as the previous group in addition to vitamin E at a dose of 100 mg/kg. Microscopic, ultrastructural, and cytokeratin immune-reactivity examination of the glands were performed. The AgNPs group showed noticeable degeneration in all structures of the gland as evident in the histological and ultrastructural examination. The AgNPs and vitamin E group revealed an improvement of the glandular elements. A significant increase in cytokeratin immune expression was found after comparison of both groups (p = 0.01). This current study shows that vitamin E has powerful antioxidant properties, which can combat the cytotoxic effect caused by AgNPs. Further studies are deemed necessary to confirm this finding using other immunohistochemical markers, such as myosin and E-cadherin.

Role of Chitosan Nanoparticles in Improving Hepatic and Renal Toxicity Induced by Silver Nanoparticles Coated by Fe3O4 in Rats

Aims: Silver nanoparticles (Ag NPs) are an important class of nanomaterials used as antimicrobial agents for a wide range of medical and industrial applications.Current study was performed to study the therapeutic effects of chitosan nanoparticles extract towards the treatments with Ag NPs in rat induced kidney and liver damage.&#x0D; Study Design: A total of 60 male adult albino rats were equally divided into six groups (G1, Control group; G2, chitosan group; G3, Ag NPs group as acute toxicity; G4, acute Ag NPs+Chitosan group; G5, Ag NPs group as chronic toxicity; G6, chronic Ag NPs+Chitosan).&#x0D; Results: Current results revealed that; a significant increase in the levels of serum ALT, AST, ALP, urea, creatinine, sodium, potassium, chloride ions and MDA in liver and kidney tissues after treatments with Ag NPs (in case of acute and chronic toxicity) as compared to control group. In contrast; a significant decrease in serum albumin, total proteins, calcium ions, SOD, catalase and GSH in liver and kidney tissues after treatments with Ag NPs as compared to control groups. Treatment of Ag NPs with Chitosan nanoparticles (Ch NPs) improved this change in liver and kidney functions as compared to Ag NPs.&#x0D; Conclusion: These findings suggested that the misuse of silver nanoparticles may contribute to continuous hepatic and renal damage. This shows that the desired dose of Ag NPs can safely be used with Chitosan in improving hepatic and renal damage in toxic group in young rats.

Differential effects of silver nanoparticles on two types of mitochondrion-rich ionocytes in zebrafish embryos

Silver nanoparticles (AgNPs) are increasingly used in our daily life and have become a potential environmental hazard. However, the toxic effects of AgNPs on the early stages of fish are not fully understood, and little is known about their effects on specific types of ionocytes. Using zebrafish embryos as a model, this study examined the effects (changes in cell number, morphology, NH4+ secretion and gene expression) of sublethal concentrations of AgNPs (0.1, 1, and 3 mg/L) on two major types of ionocytes: H+ pump-rich (HR) ionocytes, and Na+ pump-rich (NaR) ionocytes in the skin of embryos. After exposure to AgNPs for 96 h, the number of HR ionocytes significantly declined by 30% and 41% in the 1 and 3 mg/L AgNP groups, respectively. In addition, the apical opening of HR ionocytes became smaller, suggesting that AgNPs impaired the critical structure for ion transport. NH4+ secretion by HR ionocytes of embryos also declined significantly after AgNP exposure. In contrast, the number of NaR ionocytes increased by 29% and 43% in the 1 and 3 mg/L AgNP groups, respectively, while these cells deformed their shape. AgNPs altered mRNA levels of several ion channel and transporter genes involved in the functions of HR ionocytes and NaR ionocytes, and influenced hormone genes involved in regulating calcium homeostasis. This study shows that AgNPs can cause differential adverse effects on two types of ionocytes and the effects can threaten fish survival.

Post-operative Pain and Antibacterial Efficacy of Silver Nanoparticles Formulations Intracanal Medication: A Randomized Controlled Clinical Study

AIM: To evaluate the effect of using combined calcium hydroxide/silver nanoparticles or silver nanoparticles (AgNPs) or calcium hydroxide (Ca(OH)2) individually as intracanal medications in reducing postoperative pain and intracanal bacterial count. MATERIALS AND METHODS: Thirty patients with necrotic mandibular anterior teeth were randomly divided into 3 groups; Ca(OH)2 + AgNPs or AgNPs gel (Intervention Groups) or Ca(OH)2 (Control Group). Patients received a standard 2-visit endodontic treatment and recorded their pain levels after 4, 24, 48, 72 and 96 hours following the first and second visit on a modified visual analogue scale (VAS). Intracanal bacterial counts were assessed using culturing before and after instrumentation and intracanal medication. Outcome data were statistically analyzed using Kruskal-Wallis and Fisher’s Exact tests to compare between the groups and Friedman’s test to assess the changes by time. RESULTS: At 24 hours interappointment the incidence of pain was statistically significant (P = .005) as well as at 48 hours (P = .001). There was a statistically significant difference between the mean percentage reduction of anaerobic bacterial counts in the three groups with the highest percentage in the Ca(OH)2 + AgNPs group at 98.9% followed by AgNPs group 98.5% and Ca(OH)2 at 85.3% (P &lt;0.001). CONCLUSIONS: Combined calcium hydroxide/silver nanoparticles reduced the intracanal bacterial counts significantly, but adversely affected the interappointment pain. Based on that finding, this combination should be tested in different concentrations with different ratios to reach the most effective combination that reduce pain with high antibacterial efficacy.

Bioengineered phytomolecules-capped silver nanoparticles using Carissa carandas leaf extract to embed on to urinary catheter to combat UTI pathogens.

Rising incidents of urinary tract infections (UTIs) among catheterized patients is a noteworthy problem in clinic due to their colonization of uropathogens on abiotic surfaces. Herein, we have examined the surface modification of urinary catheter by embedding with eco-friendly synthesized phytomolecules-capped silver nanoparticles (AgNPs) to prevent the invasion and colonization of uropathogens. The preliminary confirmation of AgNPs production in the reaction mixture was witnessed by the colour change and surface resonance plasmon (SRP) band at 410nm by UV-visible spectroscopy. The morphology, size, crystalline nature, and elemental composition of attained AgNPs were further confirmed by the transmission electron microscopy (TEM), selected area electron diffraction (SAED), X-ray diffraction (XRD) technique, Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The functional groups of AgNPs with stabilization/capped phytochemicals were detected by Fourier-transform infrared spectroscopy (FTIR). Further, antibiofilm activity of synthesized AgNPs against biofilm producers such as Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were determined by viability assays and micrographically. AgNPs coated and coating-free catheters performed to treat with bacterial pathogen to analyze the mat formation and disruption of biofilm formation. Synergistic effect of AgNPs with antibiotic reveals that it can enhance the activity of antibiotics, AgNPs coated catheter revealed that, it has potential antimicrobial activity and antibiofilm activity. In summary, C. carandas leaf extract mediated synthesized AgNPs will open a new avenue and a promising template to embed on urinary catheter to control clinical pathogens.

Toxicity of AgNPs upon Liver Function and Positive Role of Tinospora Cordifolia: In Vivo

This experiment was premeditated to probe the toxic impact of Silver Nanoparticles (AgNPs) upon liver function parameters in male rats, as well as to demonstrate the protective effect of Tinospora cordifolia (T.C) against liver function disorders caused by AgNPs. Twenty-four rats were classified into four packs, six ones for every pack. Rats were included by control animals without treatment, while the AgNPs group included rats treated with 50μl/kg / day AgNPs. In the AgNPs + T.C group, rats were co-administered of AgNPs at a dose of 50μl/kg with T.C at a dose of 400 mg/kg. Whereas, animals of the T.C pack were treated with 400 mg/kg of T.C. The duration of the experiment was 28 days. After blood samples were taken at the conclusion of the experiment. The levels of biochemical parameters (liver enzymes) such as alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase were evaluated to detect liver function abnormalities. Thwe Pw A t e dewoe t ste user e dnoAiwoe se dsnd disnte dnirease in the activity of serum liver enzymes in comparison to the control group (p &lt; 0.05).While T. cordifolia co-treatment significantly reduced the levels of activities of those enzymes. Therefore, it can be considered that T. cordifolia effectively contributes to the protection against liver dysfunction caused by AgNPs in rats. Keywords : Silver Nanoparticles, liver dysfunction, biochemical parameters.

Evaluation of the Ameliorative Effect of Zinc Nanoparticles against Silver Nanoparticle-Induced Toxicity in Liver and Kidney of Rats.

Silver nanoparticles (Ag-NPs) have various pharmaceutical and biomedical applications owing to their unique physicochemical properties. Zinc (Zn) is an essential trace element, a strong antioxidant, and has a primary role in gene expression, enzymatic reactions, and protein synthesis. The present study aims to explore the toxic effects of Ag-NPs (50 nm) on the liver and kidney of rats and also to evaluate the potential protective effect of Zn-NPs (100 nm) against these adverse effects. Forty adult Sprague-Dawley rats were randomly divided into four equal groups: control group, Ag-NPs group, Zn-NPs group, and Ag-NPs + Zn-NPs group. Ag-NPs (50 mg/kg) and/or Zn-NPs (30 mg/kg) were administered daily by gavage for 90 days. The results showed that exposure to Ag-NPs increased serum ALT, AST, urea, and creatinine. Ag-NPs also induced oxidative stress and lipid peroxidation and increased inflammatory cytokines in hepatic and renal tissues. Moreover, histopathological and immunohistochemical examinations revealed various histological alterations and positive caspase-3 expressions in the liver and kidney following exposure to Ag-NPs. On the other hand, most of these toxic effects were ameliorated by co-administration of Zn-NPs. It was concluded that Ag-NPs have hepatotoxic and nephrotoxic effects in rats via different mechanisms including oxidative stress, inflammation, and apoptosis and that Zn-NPs can be used to alleviate these harmful effects by their antioxidative, anti-inflammatory, and antiapoptotic properties.

Zinc Nanoparticles Ameliorate the Reproductive Toxicity Induced by Silver Nanoparticles in Male Rats.

IntroductionSilver nanoparticles (Ag-NPs) are among the most commonly used nanoparticles in different fields. Zinc nanoparticles (Zn-NPs) are known for their antioxidant effect. This study was designed to investigate the adverse effects of Ag-NPs (50 nm) on the male reproductive system and also the ameliorative effect of Zn-NPs (100 nm) against these harmful effects.MethodsForty adult male rats were used in this study; they were randomly divided into four equal groups: control group, Ag-NPs group, Zn-NPs group, Ag-NPs + Zn-NPs group. Ag-NPs (50 mg/kg) and/or Zn-NPs (30 mg/kg) were administered orally for 90 days.ResultsThe results revealed that exposure to Ag-NPs adversely affected sperm motility, morphology, viability, and concentration. Ag-NPs also induced oxidative stress and lipid peroxidation in testicular tissue. The exposure to Ag-NPs decreased serum FSH, LH, and testosterone hormones. Additionally, comet assay revealed DNA degeneration in the testicular tissue of rats exposed to Ag-NPs. Histopathological examination showed various histological alterations in the testes of rats intoxicated with Ag-NPs. Furthermore, co-administration of Zn-NPs ameliorated most of the toxic effects of Ag-NPs via their antioxidative capacity.

Silver Nanoparticles Attenuate the Antimicrobial Activity of the Innate Immune System by Inhibiting Neutrophil-Mediated Phagocytosis and Reactive Oxygen Species Production.

PurposeDespite 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.MethodsAgNPs 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.ResultsThe 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.ConclusionThis 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.

Evaluation of surface analysis of gutta-percha after disinfecting with sodium hypochlorite, silver nanoparticles, and chitosan nanoparticles by atomic force microscopy: An in vitro study.

Aims and Objectives:The purpose of this study is to evaluate the surface topography of gutta-percha (GP) after disinfecting with sodium hypochlorite (NaOCl) (5.25%), silver nanoparticles (AgNPs) (70 µg/ml), and chitosan nanoparticles (ChNPs) (1.5 mg/ml) by atomic force microscopy (AFM).Materials and Methods:Forty GP cones were taken in this in vitro study. These samples were divided into four different groups such as Group I – control group (untreated GP Points) and Group II, III, and IV were treated with 5.25% NaOCl, 70 µg/ml AgNPs, and 1.5 mg/ml ChNPs, respectively. The surface topography analysis of the samples was performed using AFM.Statistical Analysis:Root mean square (RMS) and surface roughness parameters were used to compare the structure of GP points with contact mode imaging. These values were tested by IBM SPSS-20.0 version statistical software using one-way ANOVA and post hoc (Tukey's honestly significant difference) tests. They were considered statistically significant when P < 0.05.Results:The RMS and surface roughness values are significantly higher for NaOCl group (5.25% NaOCl) when compared with AgNPs group (70 µg/ml AgNPs) and ChNPs group (1.5 mg/ml ChNPs).Conclusion:This study has shown more surface topography deterioration of GP treated with NaOCl and lesser deterioration with AgNPs and ChNPs which affects postoperative prognosis.

Green synthesis of silver nanoparticles from Eriobotrya japonica extract: a promising approach against cancer cells proliferation, inflammation, allergic disorders and phagocytosis induction

Nanoparticles (NPs) have biological activities like antibacterial, antifungal, drug delivery, immunomodulation and antitumor activities. The aim of the current study was to investigate some of biomedical applications of silver NP synthesis using extracts from leaves of Eriobotrya japonica. Colour changes, UV–visible spectroscopy, SEM, zeta potential, dynamic light scattering, FTIR and XRD were used to confirm AgNPs formation. The UV–vis spectrum absorption band was observed at almost 430 nm. The SEM image shows quasi-spherical shape of AgNPs. The zeta potential demonstrated the negative surface charge of NPs. FTIR results showed the functional groups of AgNPs. Crystalline nature of AgNPs was confirmed by XRD pattern. MTT assay was used to study the anti-proliferative activity against MCF-7 and HeLa cells. Apoptosis was tested using a DNA-fragmentation test, and expression of P53. AgNPs inhibited the proliferation of MCF-7 and HeLa cells, and reduced inflammation. Treatment with AgNPs significantly decreased allergic disorder. AgNPs stimulated the phagocytosis process in BMDMs. The results suggested that AgNPs could be a promising therapy for future and preventing inflammation, reduce allergic disorders and prevent bacterial infection through the up-regulation of phagocytosis. Hence, future work such as developed and improved NPs as adjuvants, immune-modulating substances and nano-drug delivery system is needed.

RETRACTED: Tranilast ameliorated subchronic silver nanoparticles-induced cerebral toxicity in rats: Effect on TLR4/NLRP3 and Nrf-2

Silver nanoparticles (AgNPs) are widely applied in various aspects of life. However, recent studies reported their potential toxicity both on environment and human health. The present study aimed to unravel the underlying molecular mechanisms involved in AgNPs-induced brain toxicity. Moreover, chemopreventive effect of tranilast, an analogue of tryptophan metabolite and a mast cell membrane stabilizer was evaluated. Thirty Sprague Dawley rats were enrolled equally into Normal control group, AgNPs-intoxicated group (50 mg/kg, 3 times/week) and tranilast (300 mg/kg, 3 times/week)+AgNPs group. AgNPs administration triggered brain oxidative stress as depicted by reduced Nrf-2 expression, decreased TAC and GSH as well as upregulated brain lipid peroxidation. The apparent brain oxidative damage was accompanied by elevated levels of inflammatory cytokines (IL-1β, IL-6 and TNF-α). Moreover, brain levels of TLR4, NLRP3 and caspase-1 were up-regulated. Additionally, histological study indicated marked cellular injury in cerebrum and cerebellum specimens. This was concomitant with elevated serum CK activity and CK-BB level. On the other hand, tanilast administration remarkably alleviated AgNPs-induced brain toxicity. The present study shed the light on implication of TLR4/NLRP3 axis and NrF2 in AgNPs-induced brain toxicity. In addition, it explored the potential protective effect of tranilast on AgNPs-induced brain injury via antioxidant and anti-inflammatory efficacies.

Photocatalytic and antibacterial activities of AgNPs from Mesua Ferrea seed

The silver nanoparticles have been successfully prepared with Mesua ferrea seed extract by biological method. Characterizations have been made by XRD, FTIR, UV–Vis-NIR, FESEM with EDAX, DLS and HRTEM. Crystal structure and dislocation density were characterized by X-ray diffractometer and reveal that synthesized AgNPs were FCC structure and the size of AgNPs were 15 nm. Field Emission Scanning Electron Microscopy (FESEM) and High-Resolution Transmission Electron Microscope (HRTEM) characterizations were used to determine the morphology and size of the Ag nanoparticles in the range of 18–30 nm. The functional groups of AgNPs were identifying by FT-IR analysis. The UV–Vis-NIR spectral analysis is used to study optical behaviors like absorption and transmission properties of the AgNPs and optical bandgap of 2.7 eV. The dynamic light scattering (DLS) results confirm a good stabilization of the Ag nanoparticles. The photocatalytic activity of nanoparticles prepared via the biological method exhibited a higher photocatalytic activity compared to powders obtained by the hydrothermal method. The photocatalytic studies were evaluated for AgNPs by the degradation of Congo red under sunlight irradiation. The synthesized silver nanoparticles were tested against gram + Ve (Staphylococcus aureus and Bacillus subtilis) and gram − Ve (Salmonella typhi) bacteria for different concentrations like (10, 20, 30, and 40 μg/mL) and the results were discussed. The antimicrobial activity of AgNPs displayed a better zone of inhibition against selected human pathogens. The present study also investigated the toxicity effect of biogenic AgNPs against human lung adenocarcinoma cancer cells and normal human epithelial cells in vitro, and the inhibitory concentrations were found to be 30 and 40 μg/mL, respectively. We are anticipated a medicinal plant for the biological synthesis of AgNPs with the effective biomedical applications.

Double-layered acrylic resin denture base with nanoparticle additions: An in vitro study

Statement of problemWhether the addition of different antifungal nanoparticles to denture base materials may affect physical or esthetic properties of the resulting nanocomposite is unclear. PurposeThe purpose of this in vitro study was to determine how a new method of adding antifungal nanofiller affects the properties of the processed nanocomposite denture base material. Material and methodsHeat-polymerized acrylic resin specimens were prepared according to each test specification. Zirconium dioxide nanoparticles (ZrO2NPs) and silver nanoparticles (AgNPs) were added in 0.5, 1.0, and 1.5% of acrylic resin powder. The specimens were divided into 2 groups according to the acrylic resin packing method: 1 layer packed conventionally in one step and 2 layers packed in 2 steps, first with unmodified acrylic resin and then by a thin layer of modified acrylic resin before the final closure. The control group was made of unaltered acrylic resin in 1 step. Flexural strength (FS), translucency, and surface roughness (Ra) were measured. A microbial assay was performed by using the direct culture and slide count methods. Three-way ANOVA and Tukey post hoc tests were used to identify statistical differences among groups (α=.05). ResultsThe addition of ZrO2NPs and AgNPs in the 1- or 2-layer specimens reduced Candida albicans adhesion (P<.001). In the 1- and 2-layer specimens, FS significantly increased with ZrO2NPs. AgNPs decreased FS only in the 1-layer specimen (P<.001). Surface roughness was not changed for the 1- and 2-layer specimens with ZrO2NPs or the 1-layer specimen with 0.5% AgNPs (P>.05), while other AgNP groups exhibited increased surface roughness (P<.001). AgNPs significantly lowered translucency in the 1- and 2-layer specimens (P<.001), while ZrO2NPs decreased translucency only in the 1-layer specimen (P<.001). ConclusionsThe addition of ZrO2NPs in the double-layer technique decreased Candida adhesion and improved FS without affecting surface roughness, while AgNPs decreased Candida adhesion and FS and increased surface roughness. Both nanofillers decreased the translucency except 0.5% ZrO2NPs, which did not change translucency when applied in 2 layers.

EFFECT OF SILVER NANOPARTICLES SYNTHESIZED USING LEAVES EXTRACT OF OLIVE ON HISTOPATHOLOGICAL AND CYTOGENETIC EFFECTS IN ALBINO MICE

This study was conducted to examine the possible effects of Ag-NPs synthesized using the olive leaf extract on histopathology and cytogenetic effect in mice. A total of thirty albino mice aged two months were divided into five treatment groups as follows: Group 1: served as control was administrated orally with 0.3 mg/kg bw of normal saline; Group 2 and 3 were administrated orally with varying doses of Ag-NPs synthesized on olive leaf extract (10 and 100 mg/kg bw, respectively) for 30 days; Group 4 and 5 were administrated orally with olive leaf crude extract (300 and 1000 mg/kg bw, respectively) for 30 days. At the end of the experimental period, the detection of possible chromosomal aberrations in blood samples and histopathology (liver, spleen, kidney, uterus, and testes) were carried out. Statistically significant differences (P&lt;0.05) were observed for the chromosomal aberrations in all Ag-NPs groups compared to control and to crude olive leaf extract groups. Histopathological study revealed various alterations in internal organs at high doses of Ag-NPs group including inflammatory reaction, blood congestion, degeneration, fibrosis, mononuclear cell lesion, and necrosis. Slight changes were identified at both doses of crude olive extract treated groups. Based on these results, oral administration of Ag-NPs could cause genotoxic and inflammatory responses in mice and this could be representing a risk to both environment and human health.

Ameliorative Effect of Sodium Selenite on Silver Nanoparticles-Induced Myocardiocyte Structural Alterations in Rats.

BackgroundThe application of silver nanoparticles (AgNPs) is growing exponentially, and its potential damage to the cardiac remains to be elucidated. The purpose of this study was to investigate the ameliorative effect of sodium selenite on silver nanoparticles-induced myocardiocyte structural alterations in rats.Materials and MethodsForty male Sprague-Dawley (SD) rats were randomly divided into four groups: control group, AgNPs group, Se control group, and AgNPs + Se group. SD rats were administered AgNPs through a single intratracheal instillation, and sodium selenite was given by intraperitoneal injection for seven days. Cardiac function was determined by echocardiography and hemodynamic, ultrastructural changes by transmission electron microscopy examination. Mitochondrial fission and autophagy markers were measured by Western blotting.ResultsAgNPs caused a significant decrease in cardiac contraction, diastolic dysfunction, fragmentation, and lysis of the myofibrils, the formation of stenosis in the capillary, damaging the mitochondria membrane and cristae. AgNPs significantly increased mitochondrial fission markers dynamin-related protein 1 (Drp1), phospho-Drp1 (p-Drp1), and mitochondrial fission protein 1 (Fis1), as well as autophagy marker LC3 II/I (P<0.05). Treatment with sodium selenite is capable of protecting cardiac function from AgNPs toxicity through attenuating ultrastructural alterations, stabilizing mitochondrial dynamic balance and blocking mitochondrial autophagy.ConclusionWe conclude that the protection of sodium selenite against silver nanoparticles-induced myocardiocyte structural alterations is associated with stabilizing mitochondrial dynamic balance and mitophagy.

Antimicrobial Efficacy of Silver Nanoparticles Incorporated in an Orthodontic Adhesive: An Animal Study.

Objectives:This study assessed the antimicrobial efficacy of silver nanoparticles (AgNPs) incorporated in Transbond XT orthodontic adhesive used in rats.Materials and Methods:Transbond XT orthodontic adhesive containing 0%, 1%, 5% and 10% AgNPs was experimentally produced. Twenty-eight male Wistar rats were randomly divided into four groups (n=7) of control (0% AgNPs), 1% AgNPs, 5% AgNPs and 10% AgNPs. After anesthetizing the rats, one drop (10 μm) of the adhesive was applied on the central incisor, and light-cured for 20 s. Transbond XT composite (1×1×1 mm) was also applied. Another 10-μm drop was applied over it, and light-cured for 40 s. Biofilm test was carried out, and the number of colony forming units (CFUs) of Streptococcus sanguinis (S. sanguinis), Streptococcus mutans (S. mutans) and Lactobacillus acidophilus (L. acidophilus) in the saliva of rats was counted at baseline and 24 h after the application of adhesive. The data were analyzed using one-way ANOVA and Tukey’s test.Results:In presence of 5% and 10% AgNPs, S. sanguinis and L. acidophilus counts were significantly lower than those in the control and 1% AgNP groups (P<0.05). The S. mutans colony count was significantly lower in presence of all concentrations of AgNPs compared with the control group (P<0.05). The S. mutans colony count in 10% AgNP group was significantly lower than that in 1% and 5% AgNP groups (P<0.05).Conclusion:Silver nanoparticles have dose-dependent antimicrobial effects; 5% concentration is the minimum concentration of AGNPs with optimal antimicrobial efficacy against all strains evaluated in this study.