Background: The purpose of the current study was to evaluate the efficacy of a new orthodontic bonding system (Beauty Ortho Bond) involving the shear bond strength in dry and wet environments, and adhesion remnant index (ARI) scores evaluation in regard to other bonding systems (Heliosit and Resilience Orthodontic Adhesives). Materials and methods: Sixty defect free extracted premolars were randomly divided into six groups of 10 teeth each, mounted in acrylic resin, three groups for a dry environment and three for a wet one. Shear bond strength test was performed with a cross head speed of 0.5 mm/min, while surfaces of enamel and bracket-adhesive-enamel surfaces were examined with stereomicroscope For ARI scores evaluation. Data were analyzed by one way analysis of variance, least significant difference, student's t-test, and Fisher exact test. Results: The mean shear bond strength showed highest values for Resilience adhesive followed by Beauty Ortho Bond and Heliosit adhesives respectively both in dry and wet environments. Interestingly, there was a non-significant difference (P<0.05) between Resilience and Beauty Ortho Bond adhesives using least significant difference at dry environment. In wet environment the Beauty Ortho Bond showed an acceptable mean shear bond strength value (6.39 Mpa) which is considered as a clinically acceptable value. Adhesive remnant index scores demonstrated a tendency towards score 1 in dry environment, and towards score 3 in wet environment, the scores also showed a non-significant difference (P<0.05) between Resilience and Beauty Ortho Bond adhesives using Fischer exact test. Conclusion: Beauty Ortho Bond is less sensitive to wet environment than Resilience and Heliosit adhesives, therefore it has an advantage during clean up, as it reduces the risk of enamel damage during debonding procedure. Keywords: Beauty Ortho Bond, Shear bond strength, light cured composite.
So far synthesis of Gonadotropin Releasing Hormone (GnRH) analogues reported in the literature has clarified some aspects of structural activity of the naturally released GnRH. As a part of continuing efforts for further understanding of this relationship, the present investigation was undertaken which involved synthesis and biological evaluation of two GnRH analogues, firstly, by replacement of the amino acid L-Argenine in the 8th position at the backbone structure of the natural hormone by the amino acid D-Alanine; and secondly, by replacement of the amino acid L-Glycine in the 10th position by D-Alanine also at the backbone structure of the nature hormone, to obtain the following analogues respectively:
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... Show MoreObjectives: Six different Schiff bases were synthesized from ampicillin and amoxicillin with isatin, 5-bromoisatin, and 5-nitroisatin. Methods: Ampicillin and Amoxicillin are linked directly through their α-amino groups to the acyl side chain with isatin and isatin derivatives by nucleophilic addition using glacial acetic acid as a catalyst. Results: chemical structures of these Schiff bases were confirmed using FTIR, 1H NMR and elemental microanalysis. The antibacterial activity was evaluated by measuring minimum inhibitory concentration (MIC) values and showed various degrees of antibacterial activities when compared with parent drugs. Compounds 1a and 2b, which are the Schiff bases of ampicillin and amoxicillin with isatin, showed very
... Show MoreA theoretical and protection study was conducted of the corrosion behavior of carbon steel surface with different concentrations of the derivative (Quinolin-2-one), namly (1-Amino-4,7-dimethyl-6-nitro-1H-quinolin-2-one (ADNQ2O)). Theoretically, Density Functional Theory (DFT) of B3LYP/ 6-311++G (2d, 2p) level was used to calculate the optimized geometry, physical properties and chemical inhibition parameters, with the local reactivity to predict both the reactive centers and to locate the possible sites of nucleophilic and electrophilic attacks, in vacuum, and in two solvents (DMSO and H2O), all at the equilibrium geometry. Experimentally, the inhibition efficiencies (%IE) in the saline solution (of 3.5%) NaCl were studied using potentiomet
... Show MoreSynthesis of 2-(4-Acetyl-phenyl)-4-nitro-isoindole-1, 3-dione chalcones were performed by fusion of 3-nitro phthalic anhydride with p-aminoacetophenone. Then the later was grinded with different aromatic aldehydes in the presence of sodium hydroxide to produce new chalcones derivatives A3-10 without using any solvent formation of new N- arylphthailimide chalcones were confirmed by FT-IR,1HNMR, 13CNMR spectroscopy and all final compounds were tested for their antifungal and antibacterial activity some of them showed more biological activity than the standard drugs
A theoretical and protection study was conducted of the corrosion behavior of carbon steel surface with different concentrations of the derivative (Quinolin-2-one), namly (1-Amino-4,7-dimethyl-6-nitro-1H-quinolin-2-one (ADNQ2O)). Theoretically, Density Functional Theory (DFT) of B3LYP/ 6-311++G (2d, 2p) level was used to calculate the optimized geometry, physical properties and chemical inhibition parameters, with the local reactivity to predict both the reactive centers and to locate the possible sites of nucleophilic and electrophilic attacks, in vacuum, and in two solvents (DMSO and H2O), all at the equilibrium geometry. Experimentally, the inhibition efficiencies (%IE) in the saline solution (of 3.5%) NaCl were studied using potentiomet
... Show MoreBackground: The isatin molecule is present in many natural substances, including plants and animals, and is used to prepare compounds with various biological activities. Objectives: To synthesize a new series of isatin derivatives with the expectation that they will have antimicrobial activity. Methods: Thiazole Schiff bases were synthesized from various Mannich bases of isatin to evaluate their antimicrobial properties. Initially, Mannich bases (2a–e) were synthesized by reacting isatin with formaldehyde and different secondary amines. Subsequently, they were treated with 2-aminothiazole to yield the final compounds (3a–e). Spectroscopic characterization was done via FT-IR and 1H-NMR. The antimicrobial screening was conducted o
... Show MoreAn enzyme linked immunosorbent assay (ELISA) for the detection and quantitation of human immunoglobulin G (IgG) antibodies against vero- cytotoxine (VT) producing Escherichia coli serogroup O157:H7 was produced. E. coli O157: H7 lipopolysaccharide was extracted from locally isolated strains by using hot phenol- water method, followed by partial purification using gel filtration chromatography by sepharose- 4B. The purity of the lipopolysaccharide was checked by measuring the protein and nucleic acid content and then used as antigen. Four isolates of vero- cytotoxin producing E. coli serogroup O157:H7 was obtained by culturing 350 stool samples from children suffering from bloody diarrhea. These isolates were identified on bacteriological, s
... Show MoreAbstract: Objectives: To investigate the effect of temperature elevation on the bonding strength of resin cement to the zirconia ceramic using fractional CO2 laser. Background: Fractional CO2 laser is an effective surface treatment of zirconia ceramic, as it increases the bonding strength of zirconia to resin cement. Methods: Thirty sintered zirconia discs (10 mm diameter, 2 mm thickness) were prepared and divided to three groups (N=10) and five diffident pulse durations were used in each group (0.1, 0.5, 1, 5 and 10 ms). Group A was treated with 10 W power setting, group B with 20 W and group C with 30 W. During laser irradiation, temperature elevation measurement was recorded for each specimen. Luting cement was bonded to the treated z
... Show MoreAim: surface modification of titanium using fiber laser 1064 nm to enhance the bond strength to resin cement. Material and Methods: thirty titanium discs of 0.6 cm x 0.3 cm (diameter and thickness respectively) were categorized after preparation into three groups (n=10) as follows: control group with no surface treatment and two test groups were treated with fiber laser after estimation the appropriate parameters in the pilot study which are 81 ns pulse duration, 30,000 Hz frequency, 50 µm spot size and 10,000 mm/s scanning speed and different average power values (10 W and 20 W) depending on the tested group. Titanium discs surface characterization was performed by scanning electron microscope (SEM), a
... Show MoreSpergularia iraqensis sp. nov. is described as a new species from Iraq. This species has been collected from Diyala Province in the central east of Iraq; it is closely related to Spergularia rubra (L.) J. Presl & C. Presl, 1819 and Spergularia bocconei (Scheele) Graebn., 1919.
The distinguishing of the morphological characteristics of the new species alongside the two similar species are discussed with photographs, and an identification key is given for Spergularia iraqensis and other closely related species.