Background: Multidrug-resistant (MDR) enterococci have become a major problem in recent times and have been reported increasingly around the world. Lytic phages infect bacteria leading to rapid host death with limited risk of phage transduction, underlining the increasing interest in potential phage therapy in the future. Objective (s): The aim of this study is to use phage therapy as alternative approach for treatment of Enterococcus faecalis infections that recorded as MDR in Iraq to tackle this problem. Materials and Methods: Thirty E. faecalis isolates were collected from patients with different infectious diseases such as urinary tract infection (UTI), diabetic foot, septicemia, and wound infections. The isolation of specific lytic phages was from different environmental sources such as (sewage, and wastewater). The biokinetic assays were carried out to measure the characteristics of the isolated phage. The study of the bacteriophage and the formed phage cocktail infectivity against isolates E.faecalis was tested by the top layer assay. The phage endolysin was extracted from the best bacteriophage that gave best results. Results: All the isolated E.faecalis was reported as MDR in this study. About 75 E.faecalis specific phages were isolated and purified. All the isolated bacteria were 100% sensitive to the lytic phages. The formed phage cocktail was capable to create inhibition zones on the most bacterial isolates' lawns. The molecular weight and the concentration of the extracted endolysin was evaluated in this study and found to be as (48 kDa) and (0.5mg/ml), respectively. The antibacterial activity of the extracted endolysin was evaluated by the turbidity reduction assay. A clear decline in the bacterial growth was manifested (5x107 CFU/ml) to (1x104 CFU/ml), in which the bacterial growth was reduced by (3.63 log). The endolysin found to be effective against 90% of E.faeclais isolates. Conclusion: The activity of the isolated specific phage together with the activity of the formed phage cocktail, were efficient as successful and inexpensive method of therapy against MDR E.faecalis. The potential of the extracted endolysin over the phage therapy was verified in this study. The coverage rate and the absence of resistant E.faecalis to the phage and its endolysin had emphasized on the importance of this alternative therapy to commonly used antibiotics. List of abbreviation: MDR = multiple drug-resistant, E. faecalis = Enterococcus faecalis, BT = burst time, BS = burst size, IP = infective percentage, Phage =bacteriophage, CFU = Colony forming unit, kDa = Kilodalton, OD = Optical Densities.
Low-temperature stratification, high-volumetric storage capacity, and less-complicated material processing make phase-changing materials (PCMs) very suitable candidates for solar energy storage applications. However, their poor heat diffusivities and suboptimal containment designs severely limit their decent storage capabilities. In these systems, the arrangement of tubes conveying the heat transport fluid (HTF) plays a crucial role in heat communication between the PCM and HTF during phase transition. This study investigates a helical coil tube-and-shell thermal storage system integrated with a novel central return tube to enhance heat transfer effectiveness. Three-dimensional computational fluid dynamics simulations compare the proposed d
... Show MoreThe disposal of textile effluents to the surface water bodies represents the critical issue especially these effluents can have negative impacts on such bodies due to the presence of dyes in their composition. Biological remediation methods like constructed wetlands are more cost-effective and environmental friendly technique in comparison with traditional methods. The ability of vertical subsurface flow constructed wetlands units for treating of simulated wastewater polluted with Congo red dye has been studied in this work. The units were packed with waterworks sludge bed that either be unplanted or planted with Phragmites australis and Typha domingensis. The efficacy of present units was evaluated by monitoring of DO, Temperature, COD
... Show MoreThe field of structural optimization (optimal design) has grown rapidly over the past decades with many different optimization methods that could be used to produce a structure of minimum weight. This research deals with two aspects, in the first, a general numerical technique based on the finite element analysis and it suggests to investigate the preliminary behavior of metal stiffened plate under action of static load environment. The technique was included a finite element model of the structures using high- order isoparimetric plate elements to be used to create a certain models to obtain their optimum design. The models are characterized such that, each model is builded using different types of stiffener configuration. The second as
... Show MoreRisks are confronting the foundations of buildings and structures when exposed to earthquakes which leads to high displacements that may cause the failure of the structures. This research elaborates numerically the effect of the earthquake on the vertical and lateral displacement of footing resting on the soil. The thickness of the footing and depth of soil layer below the footing was taken as (0.5, 1.0, and 2.0 m) and (10, 20 and 40m), respectively. The stiffness ratio of soil to footing was also elaborated at 0.68, 0.8, 1.0, and 1.7. The results showed an increase in the verticle displacement of footing as the duration of the earthquake increases. The increase of soil layer thickness below the footing leads to a reduction in the vertical
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