Alternation of bacterial antioxidant defense pathways might affect susceptibility to antibiotics in dual ways. Using a relatively simple model based on wild-type and oxyR Escherichia coli mature biofilms, their counterpart planktonic cultures and exponentially growing planktonic cultures, we explored the role of OxyR-mediated metabolism alternations in modulation of susceptibility to antibiotics ciprofloxacin and cefotaxime. All three types of cultures were placed in fresh medium,1 h after antibiotics were added and incubation continued further for 2 h. Killing rates of antibiotics were determined, biofilm eradication using crystal violet assay was estimated, expression of rpoS, katG, sulA genes as well as HPI and HPII catalase activity were measured. Biofilms of both strains were more recalcitrant to ciprofloxacin and cefotaxime at all tested concentrations compared to exponentially growing planktonic cultures. In oxyR biofilms killing rate of ciprofloxacin was lower, and killing rate of cefotaxime was higher compared to the parental strain. Compared to biofilms, wild-type biofilm counterpart planktonic cultures showed higher tolerance to low doses of ciprofloxacin, while oxyR plankton demonstrated higher tolerance to cefotaxime. Higher recalcitrance of oxyR biofilms to ciprofloxacin may be caused by an increase in persister cells under conditions of enhanced oxidative stress and activated SOS response.
The preparatory phase since it corresponds to adolescence are the most important stages of life , where the individual 's personality to take shape at this stage and start asking questions about the same , trying to discover the positive and negative traits hehas in order to form distinctive character and also is being he have Love Poll For everything that goes on around him.
And attention to cognitive motivation is important for students because the student who owns a motive cognitively looking for self - knowledge with conviction, and learning then be meaningful and lasts long. The motive of knowledge are common in which cognitive components does not mean exclusive knowledge on academic books and research in the narrow borders but a
Background : The dermatophytesare taxonomically related fungi causing different skin infections referred to as tineas in man or ringworm in man and animals . Objective:This study was established to investigate theof effect of yellow sap and gel of Aloe vera on skin of the rabbits which infected with T.verrucosum. Methods : Twelveskin biopsy were taken from rabbits for histopathological study to know the the effects of the T.verrucosumand treated with yellow sap and gel. Results : the results of histopathological study of effect of yellow sap and gel of Aloe vera on skin of the rabbits which infected with T.verrucosum showed the concentration of the gel of aloe vera at 75% was more effected to treat the infective area of skin with T.verrucos
... Show MoreThe aim of this study was intended to study the effect of rifadin drug on lipids metabolism in the blood of the rabbits .Eight rabbits were used in the experiment ,they were divided into two groups ,first group(control group ) was administrated with 15mg/ml /day normal saline for 35 days ,while the second group (treated group )was administrated with (15/mg /kg/day) for 35 days of rifadin( capsule 300mg/kg).This study examined the influences of rifadin drug on the concentration of cholesterol , triglycerides , HDL ,LDL and VLDL in rabbits sera .The result showed that there were no significant increased (p>0.05) in cholesterol concentration in rifadin treated group compared with control group ,and th
... Show MoreBackground: Levetiracetam is a member of the new antiepileptic drugs and has a broad spectrum effect, used as an adjunctive therapy in addition to monotherapy in the treatment of partial onset-seizures. The effect of levetiracetam on the development of embryo nervous system after maternal exposure during pregnancy has not been identified. Objective: to evaluate the effect of antiepileptic drug, levetiracetam (LEV) within its therapeutic dose 350mg/Kg body weight on albino female rat to clarify its effect on the developing cerebral cortex histologically. Material And Methods: Ten pregnant female rats were separated into two groups, control group and experimental group. They were obtained from the animal house of the high institute of inferti
... Show MoreExpansive soil spreads in Iraq and some countries of the world. But there are many problems can be occurred to the structures that built on, so we must study the characteristics of these soils due to the problems that may be caused to these structures which built on these kinds of soil and then study the methods of treatment. The present study focuses on improving the geotechnical properties of expansive soils by treating it Metakaolin(M). Metakaolin (M) has never been used before as an improvement material for stabilizing the expansive soil . Metakaolin is a pozzolanic material. It’s obtained by calcination of kaolinite clay at temperatures from 700°C to 800°C. Kaolin chemical composition is
... Show More The ceramics specimens as superconducting phase (Bi2PbxSr2Ca2Cu3O10+δ) with different concentrations of Pb from (0.0-0.5) were prepared by solid-state reaction method. Superconducting samples were exposed to high humidity (RH 75% at 25ºC) for seven weeks time interval. The humidity has a negative effect on the transition temperature of superconductor phase .It destroys the superconducting phase and the samples were converting to insulator.
Aim: 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 MoreThe numerical analysis was conducted to studying the influence of length to diameter ratio (L/D) on the behavior of the soil treated with sand columns treated with 8% sodium silicate for both floating and end bearing type by using finite element method (Plaxis 3D Foundation ) for isolated foundation of real dimensions. The analysis’s study indicate that in the floating type the best improvement ratio was achieved at (L/D=8) when using columns with a diameter of (0.5, 0.7), but when using columns with a diameter of 0.3 m, it was noticed that the bearing improvement ratio increases with increasing (L/d). While the results of the analysis for end bearing type show that the higher improvement ratio was achieved at (L/D=4) when using columns w
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