Background: Recently with improvement of dental implantology science, osseointegrated implants show a considerable durability, however; failures are not completely avoidable. Matrix metalloproteinase-2 (MMP-2) expression is disturbed in many pathological conditions such as peri-implantitis and periodontitis. This study was carried out to investigate the tissue expression of MMP-2 in the extracellular matrix of osseointegrated and diseased implants. Subjects and methods: Gingival biopsies were collected from six patients having osseointegrated or working implants and twenty with diseased or non osseointegrated implants and (6) controls having no implants. In situ hybridization technique was used to analyze the changes in immunoreactivity of ECM-controlling MMP-2. Results: The findings of the present study indicate that the expression of MMP2 was significantly elevated in failed implants versus healthy implants (P<0.01). In addition, MMP-2 was detected in peri-implant sites with ongoing bone loss, cavitations and inflammatory reaction. Conclusion: The in situ hybridization technique, showed clear evidence that MMP-2, which is involved in the process of osseointegration and bone remodeling, increase greatly in the presence of bone destruction, cavitations, severe inflammation and fibrous tissue formation. The data link titanium- induced bone remodeling to changes in expression and distribution of MMP-2.
The present work involved preparation of new hetro cyclic polyacrylamides (1-9) using reaction of polyacryloyl chloride with 2-aminobenzothiazole which prepeard by thiocyanogen method in the presence of a suitable solvent and amount tri ethyl amine (Et3N) with heating. The structure confirmation of polymers were proved using FT-IR,1H-NMR,C13NMR and UV spectroscopy.Other physical properties including softening and melting points, and solubility of the polymers were also measured.
Low conversion copolymerization of N-vinyl-2-pyrrolidon M.W = (111.14) VP (monomer-1) has been conducted with acrylic acid AA and methymethacrylate MMA in ethanol at 70ºC , using Benzoyl peroxide BPO as initiator . The copolymer composition has been determined by elemental analysis. The monomer reactivity ratios have been calculated by the Kelen-Tudos and Finman-Ross graphical procedures . The derived reactivity ratios (r1 , r2 ) are : (0.51 , 4.85) for (VP / AA ) systems and (0.34 , 7.58) for (VP , MMA) systems , and found the reactivity ratios of the monomer AA , MMA is mor than the monomer VP in the copolymerization of (VP / AA) and (VP /MMA) systems respectly . The reactivity ratios values were used for microstructures calculation.
This study includes the synthesis of new derivatives of 1, 2, 4- Triazole which are contain Schiff bases derived from 1, 4, 5, 6- tetrahydropyrimidine. The structures of these derivatives were characterized from their melting points, infrared spectroscopy and elemental analysis. These derivatives were tested for inhibition of E-coli and were all found to be active.
The aim of the work is the synthesis and characterization of the tridentate Schiff base (HL) containing (N and O) as donor atoms type (ONO). The ligand is: (HL) phenyl 2-(2-hydroxybenzylidenamino)benzoate . This ligand was prepared by the reaction of (phenyl 2-aminobenzoate) with salicylaldehyde under reflux in ethanol and few drops of glacial acetic acid which gave the ligand (HL). The prepared ligand was characterized by (FT IR,UV–Vis) spectroscopy, Elemental analysis of carbon, hydrogen and nitrogen (C.H.N.) and melting point. The ligand was reacted with some metal ions under reflux in ethanol with (1 metal :2 ligand )mole ratio which gave complexes of the general formula: [M(L)2]Cl , M = Cr III La III and , Pr III Products were found
... Show MoreTwelve N-(6-sustirured benzothanol-2-y1) succinamic acids and 3-(6-substitted benzonathol-2-y1)-carbamoyl propionyl chloride were synthesized in good yields from reaction of benzonathol2-yl)
Anew mixed compound complexes derived from 2-phenyl-2-(o-tolylamino) Acetonitrile as primary ligand (L1) and histidine (L2) as secondary ligand have been prepared and characterized by conventional techniques, elemental microanalysis (C.H.N), Fourier transform infrared, ultra violet-visible spectra, , flame atomic absorption, molar conductivity, magnetic susceptibility measurement and 1H-NMR spectra. From IR data which appear chelating behavior of the amino acid ligand (L2) toward transition metal ions is via carboxylate oxygen, amino nitrogen and imidazol nitrogen as tridentate ligand while second ligand (L1) chelating through N-nitrile and N-aniline, according to all above technics the octahedral shapes were expected for these complexes as
... Show MoreThe current study was conducted for studying the impact of cold plasma on the expression level of three genes that participate in the biosynthesis of the phenylpropanoid pathway in Ocimum basilicum. These studied genes were cinnamate 4-hydroxylase (c4h), 4-coumarate CoA ligase (4cl), and eugenol O-methyl transferase (eomt). Also, the cold plasma impact was studied on the essential oil components and their relation with the gene expression level. The results demonstrated that cold plasma seeds germination of the treated groups 2 (initially for 3 minutes and 3 minutes after 7 days) ,and group 3(initially for 5 minutes and 3 minutes after 7 days) were faster than the control group. Also, the height average of the mature plants of
... Show MoreAccurate description of thermodynamic, structural, and electronic properties for bulk and surfaces of ceria (CeO2) necessitates the inclusion of the Hubbard parameter (U) in the density functional theory (DFT) calculations to precisely account for the strongly correlated 4f electrons. Such treatment is a daunting task when attempting to draw a potential energy surface for CeO2-catalyzed reaction. This is due to the inconsistent change in thermo-kinetics parameters of the reaction in reference to the variation in the U values. As an illustrative example, we investigate herein the discrepancy in activation and reaction energies for steps underlying the partial and full hydrogenation of acetyl
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