Zinc Oxide-Reduced Graphene Oxide-based Photoelectrochemical Sensor Combined with Molecularly Imprinting Technique for Sensitive Detection of Oxytetracycline / 分析化学

In this work,zinc oxide-reduced graphene oxide(ZnO-rGO)nanocomposites were fabricated using hydrothermal method,and the chemical and physical properties of the synthesized ZnO-rGO were characterized by several techniques,including X-ray diffraction and Fourier transform infrared(FT-IR)spectroscopy.A molecularly imprinted photoelectrochemical sensor based on ZnO-rGO was designed for sensitive detection of oxytetracycline(OTC).Polypyrrole(PPy)film was electropolymerized onto ZnO-rGO nanocomposites and OTC molecules were imprinted on the polymer film through hydrogen bonding.After OTC molecules were eluted,the recognition sites for OTC were left on the polymer membrane,enabling the specific detection of OTC.Linear detection of OTC was achieved in the range of 0.1-200 nmol/L with the detection limit of 0.05 nmol/L(S/N=3).The sensor was successfully applied to determination of OTC in milk and honey samples,with recoveries ranging from 95%to 107%.The developed method would provide significant reference value for effective and rapid detection of other antibiotics in the foods.

Postoperative pain incidence and intensity following root canal obturation with bioceramic and other sealers: a systematic review with meta-analysis

Aims: To investigate whether bioceramicsealers induce a lower incidence and intensity of postoperative pain compared to other sealers. Materials and Methods: Six electronic databases were searched for studies published up to April 2022, following the PICOS strategy: (P) adult patients undergoing root canal treatment or retreatment; (I) root canal filling using bioceramic sealer; (C) root canal filling using other types of sealers; (O) Primary: postoperative pain incidence and/or intensity; Secondary: number of medication intake; (S) randomizedclinical trials. Risk of bias assessment was performed with the revised Cochrane risk of bias tools for randomized trials (RoB 2). Overall certainty of evidence was assessed through the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool. Results: Ten studies were included. Eight studies had a low risk of bias, and two had some concerns risk. Meta-analyses showed no differences regarding postoperative pain intensity and incidence between bioceramic sealers and AH Plus. Number of medication intake seemed to be associated to the preoperative diagnosis. Zinc oxide-eugenol sealer demonstrated an intense postoperative pain compared to bioceramic sealers and AH Plus. GRADE analysis showed a low certainty of evidence for all outcomes. Conclusions: There seem to be no differences between bioceramic sealers and AH Plus regarding postoperative pain intensity and incidence. Number of medication intake seem to be associated to the preoperative diagnosis. Zinc oxide-eugenol evoked a more pronounced postoperative pain.

Toxicity evaluation of zinc oxide nanoparticles in vitro and in vivo on cornea / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To observe the toxic effects of zinc oxide nanoparticles(ZnO NPs)on cornea by constructing intoxicated model in vivo and in vitro.METHODS:Human corneal epithelial cells(HCEpiC)were cultured in vitro and exposed to different concentrations(0.5, 5, 12.5, 25, 50, 100, 250 μg/mL)of ZnO NPs for 24h. The cell culture medium without nano-solution was used as the blank control group. The viability of the cells was assessed by MTT assay. Three different concentrations(25, 50 and 100 μg/mL)of ZnONPs dispersions were exposed to the conjunctival sac of anesthetized mice three times a day for 7d consecutively. The phosphate buffered saline(PBS)eye group was the PBS control group. Corneal morphology was observed on 1, 3, 5 and 7d, and the eyes were removed on 8d for various laboratory examinations, including corneal pathological changes and expression levels of inflammatory factors(TNF-α, IL-6).RESULTS:After treatment of HCEpiC cells with different concentrations of ZnO NPs for 24h, the MTT results showed that Zno NPs cause damage to cells at 0.5 μg/mL, and the cell survival rate was about 80%(P<0.05). Half of the cells were killed at a dose of 5 μg/mL, the damaging effect on cells in the concentration range of 5～250 μg/mL was concentration-dependent(P<0.0001). After 7d of conjunctival capsule spotting in mice, dot-like staining of fluorescein was seen in the 25 μg/mL ZnO NPs and 50 μg/mL ZnO NPs groups. Localized circular fluorescein stained areas were seen in the corneas of the 100 μg/mL ZnO NPs group. HE staining showed that the corneal epithelial layer, stromal layer thickness and stromal layer immune cell number did not change significantly in the 25 μg/mL and 50 μg/mL ZnO NPs groups(all P>0.05), while the corneal epithelial layer thinned, the corneal stromal layer thickened and the stromal layer immune cells increased significantly in the 100 μg/mL ZnO NPs group(all P<0.05). Immunohistochemical staining showed that the number of corneal stromal immune cells producing TNF-α and IL-6 and the mean integral optical density(IOD)values of TNF-α and IL-6 were significantly higher in the 100 μg/mL ZnO NPs group than in the PBS control group(P<0.05), and the degree of inflammation response was concentration-dependent. Compared with the PBS control group, no significant increase in immune cell count and IOD values in the 25 μg/mL ZnO NPs and 50 μg/mL ZnO NPs groups(P>0.05).CONCLUSION:The toxic damaging effect of ZnO NPs on the cornea was confirmed from both in vitro and in vivo, which provided a theoretical basis for the ocular safety evaluation of ZnO NPs.

Antibacterial efficacy of chemically and plant-synthesized zinc oxide nanocomposite against Staphylococcus aureus and Escherichia coli inoculated in Tilapia fillet

Aims@#Edible coatings developed from biodegradable materials such as starch and zinc oxide nanoparticles (ZnO-NPS) are efficient antimicrobials that could be used as a food additive to reduce the bacterial load on the food surface. Therefore, this study was aimed to examine the effect of chemical and green synthesized ZnO-NPS with different concentrations on the survival of Escherichia coli and Staphylococcus aureus in fish fillets during chilling storage at 4 ± 1°C.@*Methodology and results@#ZnO-NPS were chemically prepared by mixing zinc acetate dihydrate with sodium hydroxide. Lavandula officinalis was used for the green synthesis of ZnO-NPS. The sterile biodegradable coating containing 2 and 5% of both chemically and green synthesized ZnO-NPS were made using starch, gelatin, xanthan gum and glycerol. Different bacterial cocktail strains of both E. coli and S. aureus were inoculated onto Tilapia fillet samples. The coating solution with different antimicrobials was aseptically spread in Tilapia fillets and examined periodically within two days intervals for the survival of S. aureus and E. coli during chilling at 4 ± 1 °C. Both chemically and plantsynthesized ZnO-NPS reduced the growth of both S. aureus and E. coli by about 3.7 log10 CFU/cm2 of Tilapia fillet. The incorporation of L. officinalis increased the antibacterial activity of ZnO-NPS. Staphylococcus aureus was more sensitive than E. coli for both chemically and plant-synthesized ZnO-NPS. Moreover, zinc oxide biodegradable coating extended the shelf-life of chilled Tilapia fillets by about 4 days.@*Conclusion, significance and impact of study@#The results of the current study demonstrated the incorporation of L. officinalis into ZnO-NPS biodegradable coating which may be promising in reducing microbial growth on food surfaces.

Inhibitory effects of Ag+ and ZnO+ nanoparticles on a causative agent (Neoscytalidium dimidiatum) of dragon fruit stem-canker

Aims@#This study aimed to isolate the fungal strains causing brown spot disease on dragon fruit and identify them using molecular biology techniques. The study also investigated the inhibitory effects of silver (Ag) and ZnO nanoparticles on the isolated fungal strains. @*Methodology and results @#Six fungal strains (TL1, TL2, TL3, TL4, TL5, TL6) causing brown spot disease (stem-canker) were isolated. TL1 and TL2 isolates were used for testing the antifungal features of nanoparticles. Nanoparticles were directly added to the PDA medium to make a solution with concentrations of 50, 75 and 100 ppm. The antifungal feature of nanoparticles was screened by inoculating with the fungal samples for 72 h. The inhibitory capacity of ZnO and Ag nanoparticles against fungal strains was then investigated. TL1 and TL2 samples were identified as Neocytalidium dimidiatum using the internal transcribed spacer (ITS) region. The study also revealed that silver nanoparticles were more effective than zinc oxide nanoparticles in inhibiting the growth of fungal strains that cause brown spot disease on dragon fruit. Specifically, ZnO nanoparticles had the highest inhibitory effect on TL2, 61.27% at 100 ppm and Ag nanoparticles gave the highest inhibitory effect on TL2, 85.83% at 100 ppm.@*Conclusion, significance and impact of study @#The research findings suggest that the use of Ag and ZnO nanoparticles may be an effective way to control brown dragon fruit spot disease. It may help in improving dragon fruit yield and aesthetic quality. As a result, it may help in reducing economic loss for farmers. However, further research is required.

Oxidative stress injury and transcriptome analysis of human myocardial AC16 cells induced by zinc oxide nanoparticles / 安徽医科大学学报

Objective@#To investigate the oxidative stress injury of nano zinc oxide nanoparticles(ZnO NPs) on human myocardial cells (AC16) ，and to analyze the mechanism of ZnO NPs from the transcriptome level．@*Methods@#Dynamic light scattering (DLS) was used to characterize and detect ZnO NPs．After AC16 cells were exposed to ZnO NPs at different doses and at different times，the cell survival rate was determined by CCK-8 method．AC16 cells were divided into control group，ZnO NPs (50，100，200 μmol /L) ，after 6 h treatment，the mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) were measured．AC16 cells were divided into control group，50 μmol /L ZnO NPs group and 200 μmol /L ZnO NPs group．After 6 h exposure，total RNA was extracted by TRIzol for transcriptome analysis ，and the differentially expressed genes were enriched by gene body ( GO) ，Kyoto Encyclopedia of Genes and Genomes (KEGG) . @*Results @#The results of DLS showed that the hydrodynamic diameter was ( 192. 2 ± 1. 63 ) nm and the Zeta potential was ( －23. 26 ± 1. 05 ) mV． CCK-8 results showed that the survival rate of AC16 cells decreased with the increase of dose and time of exposure to ZnO NPs. Fluorescence quantification showed that with the increase of ZnO NPs exposure dose，MMP significantly decreased at 100 μmol /L ZnO NPs(P＜0. 05) ，and ROS significantly increased at 50 μmol /L ZnO NPs(P＜0. 05) ．Using the multifunctional microplate reader，it was observed that MMP and ROS were statistically significant at 100 and 50 μmol /L ZnO NPs，respectively，showing a decrease in MMP and an increase in ROS．Transcriptome analysis showed that 1 071 genes were enriched in the 50 μmol /L ZnO NPs group compared with the control group，including 561 up-regulated genes and 510 down-regulated genes．Compared with the control group，7 164 genes were enriched in 200 μmol /L ZnO NPs group，including 4 098 up-regulated genes and 3 066 down-regulated genes．GO and KEGG analysis showed that the differential genes were mainly concentrated in ROS，antioxidant activity，mitochondrial cytochrome C release，apoptosis and other signaling pathways．@*Conclusion@#ZnO NPs can decrease the survival rate of AC16 cells and induce mitochondrial damage and oxidative stress，among which ROS-mediated oxi- dative stress and mitochondrial function changes are important toxic mechanisms of ZnO NPs induced AC16 cytotoxicity.

Effects of chemical and green nano-zinc oxide on histological changes, oxidative stress, and apoptosis in rat kidney associated with cisplatin

Abstract Cisplatin (CP) is used to treat various tumors. A main restriction of cisplatin is nephrotoxicity. This study aimed to evaluate the protective effects of ZnONPs on cisplatin-induced oxidative stress and rat kidney tissue damage. Eighty adult male Wistar rats (250g-270g) were divided into ten groups: Control (CON), Sham (SH), Bulk ZnO (BZnO), Chemical ZnONPs (ChZnONPs), Green ZnONPs (GrZnONPs), Cisplatin (CP), Cisplatin+BulkZnO (CP+BZnO), Cisplatin+Green ZnONPs (CP+GrZnONPs), Cisplatin+Chemical ZnONPs (CP+ChZnONPs), Cisplatin+Explant (CP+EX). CP was i.p administered 5mg/kg/week and BZnO, ChZnONPs and GrZnONPs were i.p administered at a dose of 5mg/kg/day. After 30 days of the treatment, the expression of apoptosis/anti apoptosis related genes oxidant/antioxidant factors and histological changes in the were studied. The CP-treated group showed a decrease in body weight, while the Co-administration of ZGNPs to CP-treated rats showed a significant increase compared to the CP group. The results showed that the increased mRNA level of bax, MDA and the decreased mRNA level of bcl2, SOD and CAT activities in kidney of CP group were improved when animals were treated with ZnO NPs. Our results showed that GrZnONPs, ChZnONPs and BZnO had the potential to protect against oxidative stress and cisplatin-induced neurotoxicity that this protective effect was more evident in GrZnONPs.

Antimicrobial photocatalysis using bio-hydrothermally synthesized Zinc oxide nanoparticles in the management of periodontitis: a prospective split-mouth, double-blind, randomized, controlled clinical trial

Abstract The antimicrobial activity of metallic nanoparticles (NPs) has been confirmed to fight a broad spectrum of microorganisms, through antimicrobial effects that are amplified when these particles are irradiated with light of the proper wavelength. This is the first study to use phytoconjugated Zinc oxide (ZnO) NPs containing traces of active biomolecules derived from Emblica officinalis (E. officinalis) plant extract in antimicrobial photocatalysis (PCT) during non-surgical periodontal therapy. Objectives This study aimed to evaluate the effects of repeated PCT application in the treatment of periodontitis, using a gel containing bio-hydrothermally synthesized ZnO NPs and visible light as an adjunct to scaling and root planing (SRP). Methodology In total, 16 systemically healthy volunteers with stage 3 grade B generalized periodontitis were recruited for this prospective double blind, randomized placebo-controlled trial. After receiving SRP, the subjects received the following interventions in a split-mouth design at baseline, 1 week and 1 month: Group 1 - Placebo gel + Sham PCT; Group 2 - Nano ZnO gel + Sham PCT; Group 3 - Placebo gel + PCT; and Group 4 - Nano ZnO gel + PCT. The site-specific profile of Porphyromonas gingivalis in the subgingival plaque and clinical parameters (Plaque Index, Gingival Index, Gingival Bleeding Index, Probing pocket Depth and Clinical Attachment Level) were assessed at baseline, 1 month and 3 months. Results All interventions tested caused participants' clinical and microbiological parameters to generally improve after 3 months. Subjects who received the Nano ZnO gel + PCT combination showed a sustained and progressive improvement in their treatment outcomes, a result that presented statistically significant differences from the outcomes obtained through the remaining interventions, at all time points during the study period. Conclusions The repeated application of PCT using bio-hydrothermally synthesized ZnO NPs can effectively complement SRP in the non-surgical treatment of Periodontitis.

The effectiveness of EDTA 17% as a cleaning solution for the fiber post space after filling with cements

Aim: To evaluate the resistance of the union between a glass fiber post and radicular dentine after cleaning the root with 17% EDTA and filling with different endodontic cements. Methods: Forty uniradicular bovine incisors were removed to obtain root lengths of 18 mm. Endodontic treatment was performed on all roots using different filling cements (zinc oxide and eugenol-based, OZE; cement based on epoxy resin, AH) and cleaning solutions (saline, SA or EDTA), which made it possible to obtain four groups: OZESA, OZEEDTA, AHSA and AHEDTA. Subsequently, 12 mm of filling material was removed from the roots, and they were prepared to receive fiber posts luted with resin cement. To execute the mechanical cycles (2x106 cycles, 90 N, 4 Hz), coronal reconstruction was performed with a silicon matrix. The roots were then sliced (2-mm thick) to perform the push-out test. The results were analyzed using analysis of variance (one factor and two factors) and Tukey's test (α=0,05). Results: Bond strength (Mpa) was significantly higher for OZEEDTA (9,18) and AHEDTA (8,70) than for OZESA (6,06) AHSA (8,7). OZEEDTA also presented the highest values in the cervical region (15,18) but was significantly lower in the apical region (2,99). However, AHEDTA had a homogeneous bond strength in all thirds. Conclusion: Regardless of the endodontic cement used, EDTA was used as an irrigating solution, culminating in a higher bond strength between the glass fiber post and dentin

Hibiscus tiliaceus mediated phytochemical reduction of zinc oxide nanoparticles and emonstration of their antibacterial, anticancer, and dye degradation capabilities

The present research focused on the green, non-toxic, low-cost synthesis of zinc oxide nanoparticles (ZnO NPs) using aqueous extract of Hibiscus tiliaceus leaves as a reducing and stabilizing agent. Thus, synthesized ZnO NPs were characterized by nanotechnological applications, i.e., ultraviolet-visible spectroscopy (UV-vis), dynamic light scattering (DLS), zeta potential, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and high-resolution transmission electron microscopy (HR-TEM). The nanotechnological applications showed that as-synthesized ZnO NPs have bandgap energy of 2.97 eV, zeta potential of ?1.2 mV, crystalline in nature (JCPDS data card no-89-1397), and an average size of 30 to 60 nm. The FTIR showed that ZnO NPs have coated with plant secondary metabolites and assisted in the process of green synthesis. The ZnO NPs exhibited broad-spectrum antibacterial activity on Gram-positive and Gram-negative bacteria. The ZnO NPs showed potential anticancer activity against human breast cancer cells MCF-7 and determined the IC50 value as 65.83 ± 2.57 µg/mL by MTT assay. Furthermore, ZnO NPs were used as nano-catalyst for dye degradation of methylene blue, methyl orange, and malachite green with NABH4 as a reducing agent. The ZnO NPs exhibited potent dye degradation capability and followed pseudo-first order kinetics. The study concluded that ZnO NPs could be highly useful as anticancer and antibacterial agents in the biomedical field, and as an environmental cleaning agent for dye degradation in textile industries.

Pharmaceutico-Analytical Study of Vanaspati Jarita Marita Yashada Bhasma

Yashada is one of the Sapta dhatu, which is chemically Zn, Yashada bhasma is used therapeutically in many diseases like Prameha, Pandu, Vatavyadi etc., in the form of Bhasma (ZnO). Objectives: To prepare Yashada bhasma and its physico-chemical analysis of Yashada bhasma. Materials and Methods: Yashada was subjected Samanya Shodhana, Vishesha Shodhana and Jarana as per Rasatarangini. Yashada marana was done as per Rasayana sara. Bhasma was subjected to physico-chemical analysis which mainly included classical Bhasma parikshas like Rekhapurnata, Varitara, Unama, Nischandrata etc and modern parameters like Acid Insoluble Ash, pH, Total Ash value etc and advanced analytical techniques like XRD, SEM and AAS. Results: After 1st Puta pale yellow colored Yashada bhasma passed classical Bhasma parikshas. In classical reference two Puta are mentioned so, the 2nd Puta was given. XRD reports shows major peaks which were identified as Zinc oxide (ZnO) compound. Hence indicates complete transformation of metal to Bhasma form. Scanning electron microscopy in Yashada Bhasma after 2nd Puta the particle size ranging from 5-10μm. AAS reports shows zinc percentage of 77.08% after 2nd Puta. Conclusion: Pale yellow coloured Yashada bhasma was prepared after two Gaja putas which passed the classical Bhasma parikshas.

Evaluation of mutagenicity of zinc oxide nanoparticles by Pig-a mutation assay in vivo / 上海预防医学

ObjectiveThe genotoxicity of zinc oxide nanoparticles （ZnO NPs） in rats was determined by Pig⁃a mutation assay in vivo. MethodsCombined with 28-day oral toxicity test， male SD rats were given ZnO NPs by oral administration for 28 days， at doses of 0， 14， 70 and 350 mg‧kg-1 （maximum concentration of nanoscale dispersion state）. Rats in control groups received 350 mg‧kg-1 of normal size ZnO， 40 mg‧kg-1 N-ethyl-N⁃nitrosourea（ENU）or 0 mg·kg-1 ZnO NPs（solvent control group） Changes of body weight were recorded. At 0， 15， 28 d and 28 d of recovery observation period， 200 μL of tail venous blood was collected from each group， which was labeled by APC mouse anti-rat erythroid cells and FITC mouse anti-rat CD59. The information of 1×106 red blood cells（RBC） from each sample were collected by flow cytometry， and the mutation rate of RBCCD59- was calculated. ResultsCompared with the solvent control group， after 15 days of intragastric administration， the mutation rate of RBC CD59- in peripheral blood of in 350 mg‧kg-1 ZnO NPs group and 40 mg‧kg-1 ENU group was significantly increased while that of in 70 mg‧kg-1 ZnO NPs group was also significantly increased after 28 days of intragastric administration.with time-response and dose-response relationship. All groups except 40 mg‧kg-1 ENU group showed no significant difference in the mutation rate of RBCCD59- in peripheral blood in comparison with the solvent control group after 28-days recovery observation. Conclusion70 and 350 mg‧kg-1 ZnO NPs can increase the mutation rate of Pig⁃a gene in peripheral blood of SD rats.

Preparation and antibacterial properties of Cu-ZnO-loaded dental veneering porcelain / 口腔疾病防治

Objective@#To investigate the antibacterial properties, biocompatibility and mechanical properties of Cu-ZnO-loaded dental veneering porcelain to provide an experimental basis for the development of new dental veneering porcelain. @*Methods@#Cu-ZnO nanoparticles were added to IPS E.max Ceram for restorative veneer porcelain at different mass percentages of 0 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, and 6 wt% using ball milling in ceramic powder. A cylindrical specimen with a diameter of 20 mm and a thickness of 2 mm was prepared by high-temperature sintering. Scanning electron microscopy was used to observe the surface morphologies of nano-Cu-ZnO and the specimens. The antibacterial effect of Escherichia coli (E. coli) was quantitatively studied by the plate colony counting method. The CCK-8 method was used to evaluate in vitro the cytotoxicity of the tested piece to mouse fibroblasts (L929). Live and dead cells were observed by fluorescence microscopy. The mechanical properties of modified IPS E. Max Ceram veneering porcelain were tested by a three-point bending strength test. @* Results @# Under the scanning electron microscope, Cu-ZnO appears with a block-like structure and can be seen dispersed in the veneering porcelain. When the nano Cu-ZnO loading was 1 wt%, 2 wt%, 3 wt%, and 4 wt%, the antibacterial rates of the specimens were 24.85%, 67.94%, 96.92%, and 99.99%, respectively, and the difference between the experimental groups and the control group was statistically significant (F = 23.308,P = 0.001). The relative growth rate of each group was greater than 80% after coculture with mouse fibroblast cells (L929) for 1 day and 3 days, and there was no significant difference between the groups. The morphology of L929 cells was normal after coculture for 24 hours. With the increase in the Cu-ZnO concentration, the flexural strength of the specimen exhibited an increasing trend followed by a decreasing trend. The bending strength of the specimen loaded with 3 wt% nano Cu-ZnO reached the maximum value (84.728 ± 6.82) MPa, and there was no statistically significant difference between groups (F = 0.633,P = 0.702).@*Conclusion@#The antibacterial rate of IPS E. max Ceram veneering porcelain loaded with 3 wt% nano Cu-ZnO was more than 96% against E. coli after high-temperature sintering at 750 ℃. The bending strength reached the maximum (84.728 ± 6.82) MPa, and there was no obvious cytotoxicity.

Zinc oxide nanoparticles synthesized using Hyssopus Officinalis L. Extract Induced oxidative stress and changes the expression of key genes involved in inflammatory and antioxidant Systems

BACKGROUND: Recent advances in the synthesis of bioactive nanoparticles resulted in the discovery and introduction of new bioactive nanoparticles to the pharmaceutical industry. In this regard, this research is aimed to synthesize the zinc oxide nanoparticles (ZnO-NPs) using Hyssopus officinalis L. extract and to evaluate the safety of nanoparticles using Balb/C mice. METHODS: Forty male mice were divided into four groups and received 0, 50, 100, and 200 mg/kg of ZnO-NPs for thirty days. At the end of the experiment, blood sugar, creatinine, aspartate aminotransferase (A.S.T.), and alanine aminotransferase (A.L.T.) were determined. Furthermore, histopathological and oxidative stress biomarker analyses in liver and kidney tissues were performed. The changes in the major inflammatory- and antioxidant-related genes were determined. RESULTS: The results showed that blood sugar and creatinine reduced significantly (P < 0.05) when 50, 100, and 200 mg/kg ZnO-NPs were supplemented to the diet. The serum ALT and AST and lipid peroxidation in the liver and kidney tissues were increased significantly (p < 0.05) when 50, 100, and 200 mg/kg ZnO-NPs were supplemented to the diet. Supplementation of ZnO-NPs suppressed the expression of antioxidant-related genes (SOD and CAT) and up-regulated the inflammatory biomarkers (iNOS and TNF- α). The concentration of 200 mg/Kg nanoparticles indicated cellular degeneration and necrosis in the liver and kidney tissues. CONCLUSIONS: Overall, it can be concluded that supplementation of ZnO-NPs synthesized using Hyssopus Officinalis L. extract in this study at 50 mg/kg or higher concentrations might be toxic to the mice.

Antibacterial Activity of Zinc Oxide Nanoparticles in Self- Curing Acrylic Resin Against Streptococcus mutans / Actividad Antibacteriana de Nanopartículas de Óxido de Zinc en Resina Acrílica Autopolimerizable contra Streptococcus mutans

Antibacterial activity of zinc oxide nanoparticles in self-curing acrylic resin against Streptococcus mutans. The main objective of this study was to investigate whether nanoparticles of zinc oxide (ZnO) in self-curing acrylic resin, hav e antimicrobial properties against Streptococcus mutans, one of the microorganisms involved in the development of caries. Self- cured acrylic resin samples were prepared by incorporating ZnO nanoparticles at different concentrations based on the minimum inhibitory concentration (MIC) for Streptococcus mutans ATCC 25175. Antibacterial activity against a biofilm was evaluated in samples that were aged in artificial saliva for different times using spectral confocal laser microscopy and scanning electron microscopy. Kruskal-Wallis test using IBM SPSS Statistics version 23.0 software (SPSS Inc. ®, Chicago, IL, United States) were used, establishing the value of p <0.05 for statistical significance. The volume of the total biomass that formed in the samples aged for one day was significantly lower than the volume of the total biomass that was formed in those aged for additional days (p <0.001). Electron microscopy analysis revealed high porosity surfaces in all samples. Bacterial clusters wer e located next to large pores and irregular surfaces, while smooth surfaces had defined and linear organization cocci or simple chains. Considering the limitations of this study, the results suggest that the antibacterial activity of ZnO nanoparticles add ed to self-curing acrylic (ALIKE) is effective, mainly in fresh 1-day samples, independent of their concentration, and in samples with 16 MIC aged for 14 days, indicating it does not lose its antibacterial activity despite setting for more days. In addition, the ZnO nanoparticles added to ALIKE have the ability to inhibit the formation of biofilms, although they do not minimize the number of viable bacteria.

El objetivo principal de este estudio fue investigar si nanopartículas de óxido de zinc (ZnO), incorporadas a acrílico acrilico de autocurado, tienen propiedades antimicrobianas contra Streptococcus mutans, uno de los microorganismos implicados en el desarrollo de caries. Se prepararon muestras de resina acrílica autopolimerizada mediante la incorporación de nanopartículas de ZnO a diferentes concentraciones basadas en la concentración mínima inhibitoria (MIC) para Streptococcus mutans ATCC 25175. Se evaluó la actividad antibacteriana contra una biopelícula en muestras envejecidas en saliva artificial para diferentes tiempos utilizando espectros microscopía láser confocal y microscopía electrónica de barrido. Se utilizó la prueba de Kruskal-Wallis utilizando el software IBM SPSS Statistics versión 23.0 (SPSS Inc. ®, Chicago, IL, Estados Unidos), estableciendo el valor de p <0,05 para la significancia estadística. El volumen de la biomasa total que se formó en las muestras envejecidas durante un día fue significativamente menor que el volumen de la biomasa total que se formó en las envejecidas durante días adicionales (p <0,001). El análisis de microscopía electrónica reveló superficies de alta porosidad en todas las muestras. Los cúmulos bacterianos se ubicaron junto a poros grandes y superficies irregulares, mientras que las superficies lisas tenían cocos o cadenas simples de organización lineal y definida. Considerando las limitaciones de este estudio, los resultados sugieren que la actividad antibacteriana de las nanopartículas de ZnO agregadas al acrílico autopolimerizable (ALIKE) es efectiva, principalmente en muestras frescas de 1 día, independientemente de su concentración, y en muestras con 16 MIC envejecidas para 14 días, lo que indica que no pierde su actividad antibacteriana a pesar de estar fraguada durante más días. Además, las nanopartículas de ZnO añadidas a ALIKE tienen la capacidad de inhibir la formación de biopelículas, aunque no minimizan el número de bacterias viables.

Infiltration by Streptococcus mutans in provisional crowns fixed by two types of cementing agents ­ pilot double-blind randomized clinical trial / Infiltração por Streptococcus mutans em coroas dentárias provisórias fixadas por dois tipos de agentes cimentantes ­ estudo clínico randomizado duplo-cego piloto

Objective: When provisional acrylic crowns are used for a long time, they become more susceptible to marginal leakage by cariogenic bacteria. The objectives of this pilot clinical study were to compare cement based on zinc oxide-eugenol and calcium hydroxide by contamination with Streptococcus mutans, and calculate the sample size for the continuation of this study. Methods: Individuals receiving provisional crowns and following inclusion/exclusion criteria, were randomly distributed into 2 groups: zinc oxide-eugenol (n=8); calcium hydroxide (n=9). The temporary crowns were made by a blind researcher and cemented by another. Patients were also blinded by the cement used inside their crowns. After 2 months, a cement sample from the crowns' peripheral inner face was collected, placed in a tube containing 1 mL of sterile saline, serially diluted, plated on Mitis Salivarius Bacitracin agar, and incubated for 48 hours. Colony-forming units (CFU/mL) were counted. A statistical power analysis was performed to calculate sample size (1-ß=80%) and the Mann Whitney test to compare both cements (α=0.05). Results: Both cements were contaminated with S. mutans, with an average of 166.6 x 102 CFU/mL for calcium hydroxide and 435.3 x 102 CFU/mL for zinc oxide-eugenol, with no significant difference (p=0.311). The sample size calculated for this study was 36 per group. Conclusion: This pilot study suggests that there is important contamination inside provisional crowns used for two months, independent of the cement. The continuation of this study is needed, with a bigger sample size, to enable a comparison between the cements.

Objetivo: Quando coroas dentais provisórias são utilizadas por um longo período, elas se tornam susceptíveis à infiltração marginal por bactérias cariogênicas. O objetivo deste estudo clínico piloto foi comparar os cimentos a base de óxido de zinco e eugenol e hidróxido de cálcio pela contaminação com Streptococcus mutans e calcular o tamanho amostral para continuação deste estudo. Métodos: Indivíduos recebendo coroas provisórias e seguindo critérios de inclusão/exclusão, foram distribuídos aleatoriamente em dois grupos: óxido de zinco e eugenol (n=8); hidróxido de cálcio (n=9). As coroas provisórias foram feitas por um pesquisador cego e cimentadas por outro. Os pacientes também foram cegos quanto ao cimento utilizado dentro de suas coroas. Depois de 2 meses, amostras de cimentos foram coletadas da face interna periférica das coroas, colocadas em um tubo contendo 1 mL de solução salina estéril, diluídas de forma seriada, plaqueadas em ágar Mitis Salivarius Bacitracina e incubadas por 48 horas. Unidades formadoras de colônias (UFC/mL) foram contadas. Um teste de poder estatístico foi realizado para calcular o tamanho amostral (1-ß=80%) e o teste de Mann Whitney para comparar os dois cimentos (α=0.05). Resultados: Os dois cimentos foram contaminados com S. mutans, com uma média de 166.6 x 102 UFC/mL para o hidróxido de cálcio e 435.3 x 102 UFC/mL para o óxido de zinco e eugenol, com nenhuma diferença significativa (p=0.311). O cálculo amostral para este estudo foi 36 indivíduos por grupo. Conclusão: Este estudo piloto sugere que existe importante contaminação dentro de coroas provisórias utilizadas por 2 meses, independente do cimento. A continuação deste estudo é necessária, com maior tamanho amostral, para possibilitar a comparação entre os cimentos.

Efecto antimicrobiano sobre Streptococcus mutans de sistema adhesivo con nanopartículas de óxido de zinc y cobre / Antimicrobial effect against Streptococcus mutans of an adhesive system with copper and zinc oxide nanoparticles

Objetivo: Determinar las propiedades antimicrobianas de la incorporación de nanopartículas de óxido de zinc y cobre en un adhesivo de grabado y lavado total sobre Streptococcus mutans en pacientes con restauraciones de resina compuesta confeccionadas con adhesivo cargado. Métodos: Este estudio clínico randomizado, participaron 25 pacientes, de ambos sexos, pertenecientes al posgrado de Ortodoncia de la Facultad de Odontología de la Universidad de Chile, en los cuales se confirmó presencia de Streptococcus mutans en saliva. Se confeccionaron restauraciones de resina compuesta oclusales, en premolares superiores con indicación de exodoncia por el tratamiento de ortodoncia, con adhesivo cargado (cuya composición es 5 / 0.2 por ciento ZnO y Cu respectivamente) y control (sin presencia de nanopartículas en su composición), según el listado de aleatorización. Se tomaron muestras microbiológicas en tres tiempos con la Técnica de la cubeta (antes, 1 semana y 4 semanas posterior a la confección de las restauraciones). Se obtuvieron, aislaron e identificaron colonias de Streptococcus mutans a partir de las muestras obtenidas. Los datos fueron analizados por el test de Mann Whittney. Resultados: El promedio del recuento de UFC (unidades formadoras de colonias) de Streptococcus mutans en el grupo experimental fue mayor posterior a la confección de las restauraciones de resina compuesta.Los resultados de la identificación molecular por PCR demuestran la presencia de Streptococcus mutans en 20 de 25 muestras. Conclusiones: No existen diferencias en el recuento de Streptococcus mutans antes y después de la aplicación del adhesivo sobre las restauraciones de resina compuesta(AU)

Objective: Determine the antimicrobial properties of the incorporation of copper and zinc oxide nanoparticles into a total rinse and etch adhesive against Streptococcus mutans in patients with composite resin restorations made with loaded adhesive. Methods: A randomized clinical study was conducted of 25 patients of both sexes from the orthodontics graduate course taught at the Dental School of the University of Chile, in whom the presence of Streptococcus mutans was confirmed in saliva. Occlusal composite resin restorations were performed in upper premolars with exodontia indicated as part of the orthodontic treatment, using loaded adhesive (composition 5 / 0.2 percent ZnO and Cu, respectively) and control (without nanoparticles in its composition), according to the randomization list. Microbiological samples were taken at three moments applying the tray technique (before, 1 week after and 4 weeks after the restorations). Streptococcus mutans were obtained, isolated and identified from the samples taken. Data analysis was based on the Mann-Whitney test. Results: Mean Streptococcus mutans CFU count in the experimental group was higher after the composite resin restorations were made. Results of PCR molecular identification show the presence of Streptococcus mutans in 20 of 25 samples. Conclusions: No differences were found in the Streptococcus mutans count before and after application of the adhesive over the composite resin restorations(AU)

Assessment of Antimicrobial Efficacy of Zinc Oxide Nanoparticles Synthesized Using Clove and Cinnamon Formulation against Oral Pathogens - An In Vitro Study.

Zinc Oxide nanoparticle is of particular interest among researchers due to its wide range of applications. Green synthesis of nanoparticles has many benefits like being eco-friendly, less time consuming, cost effective, stable operation, and more importantly the process can be carried out without the involvement of any hazardous chemicals. Clove and cinnamon are known to have antimicrobial activity. Hence, this study was conducted to assess the antimicrobial efficacy of zinc oxide nanoparticles reinforced with clove and cinnamon against oral pathogens. METHODSThis is an in vitro study. The organisms used were Streptococcus mutans, Staphylococcus aureus and Enterococcus faecalis. These bacteria were inoculated in their respective medium and incubated overnight. Agar well diffusion method was used to assess the antimicrobial efficacy of the nanoparticles at 25 µL, 50 µL and 100 µL. RESULTSZone of inhibition was found to be highest at 100 µL against Streptococcus mutans, Staphylococcus aureus, and Enterococcus faecalis (15 mm, 13 mm, and 13 mm respectively). CONCLUSIONSFindings from this study suggest that zinc oxide nanoparticles reinforced with clove and cinnamon extracts has the potential as an antimicrobial agent against Streptococcus mutans, Staphylococcus aureus and Enterococcus faecalis and can be used as an alternative to commercially available antimicrobial agents.

Assessment of Cytotoxicity, Anti-Inflammatory and Antioxidant Activity of Zinc Oxide Nanoparticles Synthesized Using Clove and Cinnamon Formulation - An In-Vitro Study.

Zinc oxide nanoparticles play a vital role in diagnostics, biomolecular detection, and microelectronics. Several conventional methods are used for synthesis of zinc oxide nanoparticles. But, toxic chemicals are required as capping agents to maintain stability, thus leading to toxicity in the environment. Thus, we need to shift to “green synthesis”. Hence, this study was conducted to assess the cytotoxicity, antiinflammatory, and antioxidant activity of zinc oxide nanoparticles reinforced with clove and cinnamon.METHODSCytotoxic effect, anti-inflammatory activity, antioxidant activity of zinc oxide nanoparticles reinforced with clove and cinnamon extract were assessed using Brine Shrimp Assay, Bovine Serum Albumin (BSA) and DPPH Assay respectively at 5 µL, 10 µL, 20 µL, 30 µL, 50 µL.RESULTSAs the concentration increased, the cytotoxicity of the nanoparticles increased. Values for anti-inflammatory property of nanoparticles was higher than the standard values at all concentrations. Percentage of inhibition was highest at 40 µL (91.1%) and 50 µL (90.5%). The values for antioxidant property of nanoparticles was found to be higher than the standard values at all concentrations except at 50 µL. Percentage of inhibition was highest at 20 µL (86.2%).CONCLUSIONSZinc oxide nanoparticles reinforced with clove and cinnamon extract have a potential as an anti-cancer, anti-inflammatory and antioxidant agent and can be used as an alternative to commercially available products.

The Impact of Zinc Oxide Nanoparticle on LH, FSH, and Testosterone Hormones in Mature Male NMRI Rats

Nanoparticles are widely applied in all aspects of modern life because of their unique features such as small size and high surface area.Several types of research have been carried out to discover the feasible detrimental impacts of Nano-particles on human reproduction. The purpose of this study was to examine the impact of zinc oxide nanoparticles in mature male rats through examining LH, FSH, and testosterone sex hormones. Therefore, 30 Naked Mole-RatInitiative (NMRI) rats were divided into 5 groups. Different doses of zinc oxide nanoparticles (250, 500 and 700 mg.kg-1) were intraperitoneally injected to animals only once. Then, the serum level of luteinizing hormone(LH), Follicle StimulatingHormone (FSH), and testosterone hormones were measured using Enzyme-Linked Immunosorbent Assay (ELISA) method after 21 days. The results were analyzed by ANOVA and Tukey tests. The results indicated that zinc oxide nanoparticles doses caused a significant increase in FSH and testosterone level of blood (Respectively) in 250 and 700mg.kg-1in comparison with the control group. Moreover, this research illustrated that zinc oxide nanoparticle can cause a dose-related increase in Testosterone and FSH hormones levels while causing no significant change in LH hormone level