Synthesis of Ag-Cu-Ni Nanoparticles Stabilized on Functionalized g-C3N4 and Investigation of Its Catalytic Activity in the A3-Coupling Reaction.

In the present research, using ethylenediamine and hydrazine hydrate as the capping and reducing agents in this investigation, respectively, Ag-Cu-Ni NPs were immobilized on the functionalized g-C3N4 surface. This nanocatalyst was studied in terms of its catalytic activities for the A3-coupling reaction to synthesize propargylamine derivatives. According to the results, in the presence of 1 mL of toluene as the solvent and 20 mg of the g-C3N4-TCT-2AEDSEA-Ag-Cu-Ni nanocatalyst, the maximum efficiency of the nanocatalyst occurred at a temperature of 80 °C. Products were purified using thin-layer chromatography plates (silica gel) by employing n-hexane/ethyl acetate with a 90:10 ratio. In addition, the prominent benefits of the synthesized nanocatalyst include its high yields of the product, cost-effectiveness, recyclability, and easy separation. The novelty of the catalyst is due to the presence of Ag-Cu-Ni nanoparticles at the same time in the structure of the functionalized g-C3N4 substrate. So, Ag-Cu-Ni can be strongly connected to the substrate. The structure of the synthesized nanocatalyst was characterized using Fourier transformed infrared spectroscopy, X-ray powder diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, vibrating-sample magnetometry, and transmission electron microscopy.

Creating Antibacterial Properties in Flowable Dental Composites by Incorporation of 3, 4-dihydropyrimidin-2(1H)-ones

ABSTRACT Objective: To investigate the antibacterial, mechanical, physical properties and water sorption of flowable dental composites containing 3,4-dihydropyrimidin-2(1H)-ones. Material and Methods: 3,4-dihydropyrimidin-2(1H)-ones was synthesized and the antibacterial activity of flowable dental composites containing 0-5 wt% 3,4-dihydropyrimidin-2(1H)-ones and also of their mechanical and physical properties on flowable dental composites were investigated. Flexural strength was measured by a three-point bending test. Compressive strength (CS), Water sorption (WS) and depth of cure (DOC) were investigated. The data were analyzed by One-way ANOVA test. The level of significance was determined as p<0.01. Results: The direct contact test demonstrates that by increasing the 3,4-dihydropyrimidin-2(1H)-ones content, the bacterial growth is significantly diminished (p<0.001). The average flexural strength results show that with increasing 3,4-dihydropyrimidin-2(1H)-ones until 3% in the composite, no significant difference was observed in flexural strength (p>0.001) and the mean of compressive strength results show no significant difference between 0-4% groups (p>0.001). The mean of water sorption and depth of cure results shows no significant difference between groups (p>0.001). Conclusion: Incorporation of 3,4-dihydropyrimidin-2(1H)-ones into flowable resin composites in 3% wt can reduce the activity of Streptococcus mutans.

Biocompatibility of a New Antibacterial Compound and its Effect on the Mechanical Properties of Flowable Dental Composites (Animal Study).

STATEMENT OF THE PROBLEM: Recently, new compound of 3, 5-dimethyl-1-thiocarboxamide pyrazole has been composed with excellent antibacterial property. Biocompatibility and its effects on mechanical properties of dental composites should be considered before clinical use. PURPOSE: The purpose of this study was to evaluate the biocompatibility of 3, 5-dimethyl-1-thiocarboxamide pyrazole as a new antibacterial compound and its effect on the mechanical properties of dental composites. MATERIALS AND METHOD: In this experimental study, a new antibacterial compound was synthesis by reaction between Thiosemicarbazide and 2, 4-Pentandione and tested on thirty male albino Wistar rats weighting 200-250gr. Rats were randomly divided into 3 groups of 10, each rat received 3 implants of 3,5-dimethyl-1-thiocarboxamide pyrazole, penicillin v and empty polyethylene tube. A pathologist, who was unaware of types of tested materials and timing, performed the examination of specimens. The depth of cure and flexural strength of resin composite was measured using Iso4049 standard technique. Compressive strength was determined according to Iso9917 standard. RESULTS: This compound was biocompatible and there was no significant difference in flexural strength and compressive strength of the composites containing 1% of this compound with the control group (p> 0.05). CONCLUSION: The 3, 5-dimethyl-1-thiocarboxamide pyrazole with a concentration of 1% in flowable composites can be very effective in preventing secondary caries.

Prevention of secondary caries by a new antibacterial compound.

BACKGROUND: Since secondary caries is one of the main problems of dental composites. The creation of an antibacterial property in these composites is essential. The objective of this study was to synthesize 3-(2, 5-dimethylfuran-3-yl)-1H-pyrazole-5(4H)-one and check its biocompatibility and antibacterial properties in flowable dental composites. MATERIALS AND METHODS: In this animal study, the antibacterial activity of flowable resin composites containing 0-5 wt% 3-(2,5-dimethylfuran-3-yl)-1H-pyrazole-5(4H)-one was investigated by using agar diffusion and direct contact tests on the cured resins. Statistical analysis was performed using one-way ANOVA test (P < 0.001). Thirty male albino Wistar rats were used, weighing 200-250 g. Animals were randomly divided into three groups of ten; each animal received three implants, 3-(2, 5-dimethylfuran-3-yl)-1H-pyrazole-5(4H)-one, penicillin V, and an empty polyethylene tube. A pathologist, without knowing the type of material tested and the timing of the test, examined the samples. Statistical analysis was performed using Kruskal-Wallis test (P < 0.001). RESULTS: According to our findings, although the agar diffusion test reveals no significant difference between the groups, the direct contact test demonstrates that, by increasing the 3-(2,5-dimethylfuran-3-yl)-1H-pyrazole-5(4H)-one content, the bacterial growth was significantly diminished and the 3-(2,5-dimethylfuran-3-yl)-1H-pyrazole-5(4H)-one has a good biocompatibility (P < 0.05). CONCLUSION: Incorporation of 3-(2,5-dimethylfuran-3-yl)-IH-pyrazole-5(4H)-one into flowable resin composites can be useful to prevent Streptococcus mutans activity.

Internet Addiction Among Iranian Students of Medical Sciences

Abstract Objective: To identify the prevalence of Internet addiction (IA) and associated factors among Iranian medical students. Material and Methods: The cross-sectional survey was conducted on a random sample of 400 students. The self-administered questionnaire consisted of two sections: the first section was sociodemographic data, data about student's relations, and Internet use characteristics; the second part aimed at assessment of the level of IA using Young's 20-item scale for IA. Data analyzed in SPSS 20 at 0.05 significant level. Results: Considering their familiarity with the Internet, 80.3% stated personal experience and 12.3% individuals stated educational periods held outside the university. The most locations of using the Internet were dormitories (21.0%) and houses (43.5%). Concerning hours of Internet use, 45.2% used the Internet more than two hours per day. One hundred sixty-eight individuals (42.0%) stated that they used the Internet less than 15% for university activities. One hundred eighty-eight individuals (47.0%) used VPN and 75.5% were dissatisfied with Internet speed 61.2%. A total of 64.3% had a poor dependency on the Internet and the prevalence of IA was 3.5%. The mean score of IA questionnaire was 43.98 ± 15.92 from 125. The mean score of IA was higher in the male sex, but there was no significant correlation between sex and IA (p>0.05). There was not a significant correlation between the field of study and the year of entrance. Conclusion: The prevalence of Internet addiction among medical students was low. Identification of factors associated with IA can help in the planning of preventive programs to raise students' knowledge about the hazards IA.

Comparison of TNF-α and IL-1ß Concentrations in Gingival Crevicular Fluid During Early Alignment Stage of Orthodontic Treatment in Adults and Adolescents

Abstract Objective: To compare the levels of TNF-α and IL-1β in the gingival crevicular fluid (GCF) during early leveling stage of orthodontic treatment. Material and Methods: This study was carried out on 20 orthodontic patients, including 10 teenagers and 10 adults. Before bonding, GCF was collected with a paper strip in gingival sulcus of maxillary right central incisor on the disto labial aspect for 60 seconds, followed by bonding and insertion of initial 14 NiTi archwire. GCF collection was repeated 24 hours, 7 days, and 28 days after bonding. Measurement of TNF-α and IL-1β levels was done utilizing Enzyme-Linked Immunosorbent Assay (ELISA). Data were analyzed in SPSS using repeated measurement test. Results: Concentration of TNF-α and IL-1β increased after treatment. There was no significant relationship between TNF-α and IL-1β concentrations subsequent to bonding in comparison to the baseline. There was no significant relationship in TNF-α and IL-1β level changes in the two age groups and between males and females. Conclusion: Concentration of TNF-α and IL-1β increased after treatment. Age and sex had no statically significant effect on the concentration of TNF-α and IL-1β.

Oral Health Literacy and Related Factors among Pregnant Women Referring to Health Government Institute in Kerman, Iran

Abstract Objective: To evaluate oral health literacy among pregnant women in Kerman, Iran. Material and Methods: The present cross-sectional study was conducted on 169 pregnant women referring to government institute. Data were collected by demographic profile (including age, number of children, educational level, dental attendance before pregnancy and economic status), 17-item oral health literacy questionnaire consisting of four domains (including reading comprehension, numeracy, listening, and decision-making skills), self-assessment oral health status, DMFT index and oral health behavior. Data were analyzed by SPSS version 21 software using ANOVA and Chi-square tests at a significance level of 0.05. Results: The mean age of participants was 27.92 ± 5.25 years, 38.2% of them had bachelor's degree, 35.8% had dental attendance before pregnancy and 29.1% brushed daily their teeth twice or more. Dentists were the most frequent source of oral health information. Moreover, 60.0% believed their oral health was to be moderate, and 59.4% had inadequate oral health literacy. There was also a significant correlation between educational level, monthly income and dental attendance before pregnancy. Conclusion: Our results showed inadequate oral health literacy among pregnant women, highlighting the necessity of dental consultation before pregnancy.

Synthesis and characterization of NiFe2O4@Cu nanoparticles as a magnetically recoverable catalyst for reduction of nitroarenes to arylamines with NaBH4.

In this research, a simple and efficient method for synthesis of magnetically separable NiFe2O4@Cu nanocomposite under co-precipitation conditions was described. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), atomic absorption spectroscopy (AAS), Brunauer-Emmett-Teller (BET) and vibrating sample magnetometer (VSM) analyses confirmed the construction of NiFe2O4@Cu nanoparticles. The prepared core-shell nanocomposite showed a satisfactory catalytic activity for NaBH4 reduction of nitroarenes to arylamines. All reactions were carried out in a mixture of H2O-EtOH (1.5:0.5mL) within 1-12min under reflux conditions. The Cu nanocatalyst can be easily separated by a magnet and reused seven consecutive runs with no obvious loss of activity.