Staphylococci are common commensals in human beings, yet certain species are pathogenic. Staphylococcus aureus, particularly, is a very virulent human pathogen. The capacity of staphylococci to sense the density of bacterial cell, i.e., quorum, and thereafter respond via genetic modifications is attributable to one primary mechanism known as accessory gene regulator (Agr). Agr's extracellular signal is a peptide that is posttranslationally modified with a thiolactone molecule. Agr is in charge of the upregulation of numerous exotoxins and hydrolyzing enzymes, as well as the downregulation of many colonization determinants, under circumstances of high cell density. This modulation is critical for the scheduling synthesis of virulence determinants throughout the infection course and the establishment of acute illness, whereas low Agr activity is linked to persistent staphylococcal infections, such as biofilm development. Moreover, Staphylococcal Accessory Regulator Aِ (SarA) controls the establishment of biofilm in S. aureus that hinders the production of nuclease and protease via triggering the P2 and P3 promoters resulting in the activation of RNAII and RNAIII, respectively. SarA also endures the transcription of agrA and saeS, and many virulence determinants including hla, hlb, and hlg coding α-, β-, and γ-hemolysins, respectively. Upon the aforementioned facts, the present review will shed some light on the Quorum Sensing (QS) in S. aureus, particularly, the Agr and Sar systems and how these systems control the pathogenicity of this spe
Background: Complete removal of filling material from the root canal is an essential requirement for endodontic retreatment. The purpose of the present study is to evaluate and compare the dissolving capabilities of various solvents (Xylene, Eugenate Desobturator, Eucalyptol, EDTA and Distilled water (as a control)) on four different types of sealer (Endofill, Apexit Plus, AH Plus and EndoSequence bioceramic sealer). Materials and method: Eighty samples of each sealer were prepared according to the manufacturers' instructions and then divided into ten groups (of 8 samples) for immersion in the respective solvents for 2 and 5 min immersion periods. Each sealer specimen was weighed to obtain its initial mass. The specimens were immersed in
... Show MorePorosity is important because it reflects the presence of oil reserves. Hence, the number of underground reserves and a direct influence on the essential petrophysical parameters, such as permeability and saturation, are related to connected pores. Also, the selection of perforation interval and recommended drilling additional infill wells. For the estimation two distinct methods are used to obtain the results: the first method is based on conventional equations that utilize porosity logs. In contrast, the second approach relies on statistical methods based on making matrices dependent on rock and fluid composition and solving the equations (matrices) instantaneously. In which records have entered as equations, and the matrix is sol
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Abstract
The present research paper provides an analysis of Thomas Dekker’s
exaltation of the figure of the Babylonian woman as a tragic heroine in his dramatic
art. The paper falls into two sections. The first section outlines the deliberate
mispresentation of the figure of the Babylonian woman in the Bible and the
misreading of that figure. The second section reveals Dekker’s rectification of the
distorted image of the Babylonian woman, whom he defends and glorifies as a
heroine and a victim of misinterpretation and conspiracy.
Abstract
We Can Summarize This Research According To the Following Points
A- result
1- We conclude a new method to teach the recitation we call it (listening
method) which consist of four steps (introduction , listening ,continuity,
evaluation )
2- This research get many listening skills that educated need it when
listen to (holy quran) beside to many propositions that help to develop
it.
3- This research briefs some principles that help the teacher when use
listening method.
B- conclusion
1- The best way to teach and learn the recitation of holy quran is by
using listening skill because the prophet (pease be upon him )learn
the holy quran by it from jebrel (pease be upon him ) and then
teach
Background: The present study aimed to assess the distribution, prevalence, severity of malocclusion in Baghdad governorate in relation to gender and residency Materials and Methods: A multi-stage stratified sampling technique was used in this investigation to make the sample a representative of target population. The sample consisted of 2700 (1349 males and 1351 females) intermediate school students aged 13 years representing 3% of the total target population. A questionnaire was used to determine the perception of occlusion and orthodontic treatment demand of the students and the assessment procedures for occlusal features by direct intraoral measurement using veriner and an instrument to measure the rotated and displaced teeth. Results a
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Background: Autism spectrum disorder (ASD) is characterized by impairments in social interaction and communication, restricted patterns of behavior, and unusual sensory sensitivities. Saliva may provide an easily accessible sample for analysis. Some salivary constituents levels altered in adolescents with ASD including antioxidants . This study aimed to investigate salivary physicochemical characteristic in relation to oral health status among adolescent with ASD. Materials and methods: Two groups were included in this study: forty institutionalized autistic adolescents and forty apparently healthy school adolescents with age range (12-15 years old, only males) selected randomly from Baghdad. Each group subdivided into two groups according
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Health insurance and its benefits are of great importance and impact on the employees who represent the human capital of each organization because they are related to the health reality. The study took into account the most important and the last of his writing of the concepts and literary reviews and enriched the theoretical part of the practical side has addressed the financial data and analysis for the period from 2013 to 2017 to know the impact and the relationship between the variables that They were reviewed on the theoretical side. The study came out with a number of results, on the basis of which practical conclusions were drawn and reflected what was observed on the basis of which the recommendations were formulated