Objectives The strategies of tissue-engineering led to the development of living cell-based therapies to repair lost or damaged tissues, including periodontal ligament and to construct biohybrid implant. This work aimed to isolate human periodontal ligament stem cells (hPDLSCs) and implant them on fabricated polycaprolactone (PCL) for the regeneration of natural periodontal ligament (PDL) tissues. Methods hPDLSCs were harvested from extracted human premolars, cultured, and expanded to obtain PDL cells. A PDL-specific marker (periostin) was detected using an immunofluorescent assay. Electrospinning was applied to fabricate PCL at three concentrations (13%, 16%, and 20% weight/volume) in two forms, which were examined through field emission scanning electron microscopy (FESEM). The isolated hPDLSCs were implanted on the fabricated PCL. After 21 days, FESEM was conducted to evaluate the implanted scaffolds, and an MTT assay was performed to characterize the biological response of the PCL scaffold at different cell exposure durations (24, 48, and 72 h). Results Periostin was expressed in the expanded PDL cells, and this result revealed that 20% weight/volume PCL scaffold with a pore size of more than 10 μm was the best. The growth rates of PDLSCs were high. Cytotoxicity test of fabricated PCL scaffold demonstrated no significant change in the cell viability when compared with the negative control and no deteriorating or inhibitory effect on growth after different durations. Conclusions A cell sheet was successfully formed by using PCL as a scaffold to cover dental implants and promote PDL cell attachment, proliferation, and growth for biohybrid implant construction.
The goal of this investigation is to prepare zinc oxide (ZnO) nano-thin films by pulsed laser deposition (PLD) technique through Q-switching double frequency Nd:YAG laser (532 nm) wavelength, pulse frequency 6 Hz, and 300 mJ energy under vacuum conditions (10-3 torr) at room temperature. (ZnO) nano-thin films were deposited on glass substrates with different thickness of 300, 600 and 900 nm. ZnO films, were then annealed in air at a temperature of 500 °C for one hour. The results were compared with the researchers' previous theoretical study. The XRD analysis of ZnO nano-thin films indicated a hexagonal multi-crystalline wurtzite structure with preferential growth lines (100), (002), (101) for ZnO nano-thin films with different thi
... Show MoreThe current research deals with the dialectical relationship resulting from the conflict in the violent combination and construction of the living ( the actor)and the dead (the item) in the structure of the Sinography construction and the emergence of the theatrical play space , which can be summed up by the following question: what is the nature of the dialectical relationship between the living (the actor) and the dead( the item) in the Sinography creation, which limited the research in a central objective : to identify the controversy of the living (actor) and the dead (item) in the performance unit of the theatrical scene . The research, in its objective limits set forth in its methodological framework, analyzes this controversy in o
... Show MoreThe research aims to shed light on the amount of proceeds annual tax for each of the way the contract total and percentage of completion method - see which is better - as well as the current problems arising from the application method of the contract in full in settling accounts tax - to identify problems - related to postpone settling accounts tax in accordance with the way the contract fully and determine the advantages and disadvantages of each of the methods through practical application , and then use the results as inputs to help in the decision to confirm the continuation of the GCT using a full decade in settling accounts tax for long-term construction contracts or forgo them.
Were the result of research the existence of
... Show MoreIntroduction: This study aimed to assess the color change of human teeth with artificial enamel white spot lesions (WSLs) after sandblasting with bioactive glass, resin infiltration, and microabrasion and to test color stability after pH cycling. Methods: Fifty extracted human mandibular first molars were randomly assigned into five groups: Sound, WSLs (untreated), and WSLs sandblasted with bioactive glass (Sylc), WSLs treated by resin infiltration (ICON), and WSLs treated by microabrasion (Opalustre), respectively. All specimens underwent a pH cycling procedure. The color parameters for each specimen were assessed using an Easyshade dental spectrophotometer at different time stages then the color changes (ΔE) were calculated. Results: The
... Show MoreThe audit profession today gets an increasing interest by the financial , economic and legal contemporary societies , because of the importance of the technical & neutral auditor’s opinion to the financial reports beneficiaries in order to enable them making their investment decisions , but some of them whom suffered damage or loss when they made that decisions according to the mentioned financial statements which consolidated with auditor’s report , exposed the function to a responsibility and credibility crisis in addition to missing the trust especially at the latest years. They always ask why or what is the reason that cause the auditor didn’t giving us any warning signs about the economic mater for that companies.
Purpose This study investigated periodontal ligament (PDL) restoration in osseointegrated implants using stem cells. Methods Commercial pure titanium and zirconium oxide (zirconia) were coated with beta-tricalcium phosphate (β-TCP) using a long-pulse Nd:YAG laser (1,064 nm). Isolated bone marrow mesenchymal cells (BMMSCs) from rabbit tibia and femur, isolated PDL stem cells (PDLSCs) from the lower right incisor, and co-cultured BMMSCs and PDLSCs were tested for periostin markers using an immunofluorescent assay. Implants with 3D-engineered tissue were implanted into the lower right central incisors after extraction from rabbits. Forty implants (Ti or zirconia) were subdivided according to the duration of implantation (healing period: 45 o
... Show MoreWheat straw was modified with malonic acid in order to get low cost adsorbent have a good ability to remove copper and ferric ions from aqueous solutions, chemical modification temperature was 120°C and the time was 12 h. Parameters that affect the adsorption experiments were studied and found the optimum pH were 6 and 5 for copper and iron respectively and the time interval was 120 min and the adsorbent mass was 0.1 g. The values for adsorption isotherms parameters were determined according to Langmuir [qmax were 54.64 and 61.7 mg/g while b values were 0.234 and 0.22 mg/l] , Freundlich [Kf were 16.07 and 18.89 mg/g and n were 2.77 and 3.16], Temkin [B were 0.063 and 0.074 j/mol and At were 0.143 and 1.658 l/g] and for Dubinin-Radushkev
... Show MoreThe present research deals with the spatial variance analysis in Jwartadistrict and conducting a comparison on the spatial and seasonal changes of the vegetation cover between (2007-2013) in order to deduce the relationship between the vegetation density and the areas which are exposed to the risk of water erosion by using Plant Variation Index NDVI) C (coefficient and by using Satellite images of Landsat satellite which are taken in 2/7/2007 and Satellite images of Landsat satellite taken in 11/1/ 2013, the programs of remote sensitivity and the Geographic Information Systems.
The study reveals that there is a variance in the density of vegetation cover of the area under study betwee 2007 and 2013. Howev
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