ABSTRACT
particles are one of functional nanotechnology filed. These nanoparticles have antibacterial and antifungal characteritic. Combination therapy is one of new and specific method for therapy of diseases in medicine and pharmacology. Some plants are useful in growth inhibition of Aspergilus Niger. This study was done to evaluate the synergic effect of alcoholic eucalyptus and nanosilver on colony count of Aspergilus Niger. In this laboratory study PAN were cultured in PDA medium. Five experimental and one control group were designed for the comparison of synergic effect of alcoholic eucalyptus and nanosilver, nanosilver 50ppm, nanosilver 12.5ppm, eucalyptus ethanolic extract 100%, eucalyptus ethanolic extract 100% mixed with nanosilver 12.5ppm, eucalyptus ethanolic extract mixed with 50ppm, and double distilled water were given to group 1, 2, 3, 4, 5 and control group respectively. Morphological, diameter, and colony numbers in various culture media were compared subsequently. The repeated number of Aspergilus Niger were 24, and they were chosen randomly. Data were analyzed using SPSS-15 and ANOVA test. The Aspergilus niger colony were reduced 8 days following treatment from 200 colony in control group to 90, 75, 55 and 43 in nanosilver group in 12.5 ppm, nanosilver group in 50 ppm, nanosilver group in 50 ppm mixed with eucalyptus ethanolic extract and finally eucalyptus ethanolic extract group, respectivley [P<0.05]. The colony count 24 day following treatment were reduced from 200 colony in control group to 42, 14 and 2 in eucalyptus ethanolic extract group, nanosilver group in 12.5 ppm mixed with eucalyptus ethanolic extract and finally nanosilver group in 50 ppm mixed with eucalyptus ethanolic extract, respectivley [P<0.05]. This study showed that nanosilver with 50 ppm concentration mixed with eucalyptus ethanolic extract have synergic effect on reducing the Aspergilus niger growth rate
ABSTRACT
Nanosilver particles are one of the functional nanotechnology filed. These nanoparticles have antibacterial characteritics. Combination therapy is one of new and specific therapeutic regiment in medicine. Eucalyptus plant is useful in growth inhibition of bacteria. This study was done to evaluate the inhibitory effect of alcoholic eucalyptus extract with nanosilver on E.coli growth. In this laboratory study, E.coli was cultured in nutrient agar medium. Primarily 50 microl of bacteria was inocolulated in each plate, antibiograms disc contaminated with 3.1, 6.25, 12.5, 25 and 50 ppm concentration of nanosilver accompanied with 100% of etanolic extract of eucalyptus were placed in each plate subsequently. Diameter of inhibitory zone were evaluated following 24, 48, 72 hrs in 6[th] and 8[th] days. Data were analyzed using SPSS-15, ANOVA and Tukey tests. After six days, inhibitory growth zone diameter of E.coli was 0.5 mm. This diameter in experimental group with 3.1, 6.25, 12.5, 25 and 50 ppm of nanosilver in combination with etanolic extract of eucalyptus were 0.55, 0.58, 0.82, 0.83 and 1.02 mm. Inhibitory growth zone in group of 12.5, 25 and 50 ppm of nanosilver was significant in compared to the control [P<0.05]. The most proper time of inhibitory effect on E.coli growth is six day after treatment in combination of 50 ppm nanosilver particles with extract of eucalyptus
ABSTRACT
Reinforcement with fiber is one of effective methods for improvement in flexural properties of indirect composite resin restorations. The composition of the overlying veneering composite plays a critical role in the flexural properties of the final fiber reinforced restoration. The aim of this in-vitro study was to evaluate the effect of fiber reinforcement on the flexural strength of three laboratory-processed fiber-reinforced composite resins. In this experimental-laboratory study, 72 bar type specimens [3225 mm] were constructed by using three types of fiber-reinforced composite resins [Gradia, Signom, Bellglass] and one Plexiglas mold. In each type of composite resin, two groups [one with fiber and one without fiber] were constructed. These specimens were tested by the three-point bending method to measure flexural strength. Data were statistically analyzed with two way ANOVA, Tukey and T-test at 0.05 significance level. The mean flexural strength of Gradia with fiber was higher than the other groups [150.14 MPa] and the mean flexural strength of Signom without fiber was the least [60.53 MPa]. There was a significant difference between the mean primary fracture force in the three groups [P<0.001]. Within the limitations of this study, it may be concluded that reinforcement with fiber considerably increases the fracture resistance of composite specimens and the overlying veneering composite may play an important role in the transverse strength of fiber reinforced composite specimens