Periodontitis is one of the most prevalent bacterial diseases affecting man with up to 90% of the global population affected. Its severe form can lead to the tooth loss in 10-15% of the population worldwide. The disease is caused by a dysbiosis of the local microbiota and one organism that contributes to this alteration in the bacterial population is Prophyromonas gingivalis. This organism possesses a range of virulence factors that appear to contribute to its growth and survival at a periodontal site amongst which is its ability to invade oral epithelial cells. Such an invasion strategy provides a means of evasion of host defence mechanisms, persistence at a site and the opportunity for dissemination to other sites in the mouth. However, previous studies have demonstrated that invasion of the mammalian cells in a population by P. gingivalis is heterogenous, with some cells becoming heavily invaded while others harbour no or only a few bacteria. An understanding of this heterogeneity may throw light on the mechanisms involved and we hypothesised that the phase of the host cell cycle may explain this phenomenon. In an attempt to study the factors influencing P. gingivalis invasion and the cell response to that invasion, a standard antibiotic protection assay was employed and an oral keratinocyte cell line, H357. The results showed that P. gingivalis NCTC 11834 invasion was significantly increased with increasing time of exposure to the cells and the cell density. This may reflect an increased host cell surface area available for bacterial attachment. No effect on invasion of P. gingivalis invasion was observed by the bacterial growth phase, H357 cell passage number or whether cells were pre-incubated with P. gingivalis lipopolysaccharide. Epithelial cells did, however, respond to the presence of P. gingivalis in a number of ways. For example, the mRNA expression of endothelin-1 and urokinase receptor were upregulated with increasing P. gingivalis infection time, suggesting that these proteins could act as inflammatory mediators and possibly as useful markers of the severity of periodontal disease or in the diagnosis and treatment of periodontitis. iii Secondly, in an attempt to investigate the reason for the observed heterogeneous P. gingivalis invasion of H357 cell populations, the effect of cell cycle phase on P. gingivalis invasion was investigated. H357 cells were synchronized by serum starvation. On re-introduction of serum, characterisation of cell cycle phase distribution was performed by flow cytometry following staining with propidium idodide (PI) or by immunofluorescence using bromodeoxyuridine (BrdU), which specifically identifies cells in S-phase. The effect of cell cycle phases on P. gingivalis invasion was measured using the antibiotic protection assay, immunofluorescence and flow cytometry and these were correlated with gene and surface expression of the urokinase receptor and the α5-integrin subunit, which is thought to mediate P. gingivalis invasion. Results showed that the percentage invasion was enhanced with increasing serum re-introduction time, and positively correlated with the number of cells in S-phase. In addition, flow cytometry data showed that the highest association of fluorescent P. gingivalis was with PI positive S-phase cells. Moreover, BrdU positive S-phase cells were 3 times more likely to be invaded and contained 10 times more P. gingivalis than cells in other phases. Also, α5-integrin was more highly expressed in cells in S-phase than other phases, which could explain the mechanism underlying this enhanced invasion. Data presented here have suggested that P. gingivalis targeting of cells in S- phase could, in vivo, allow preferential invasion of the junctional epithelial cells which turns over rapidly. The data presented in this thesis suggest that P. gingivalis invasion is greatly dependent on several factors attributed to the host, the bacteria itself, and to the environment which the bacteria reside in. The invasion occurs within a population of host cells in a heterogeneous fashion, and is dependent on the cell cycle phase, specifically S-phase. This novel finding, in addition to the previously reported mechanisms of P. gingivalis invasion, increases our understanding of this virulence trait and suggests that such a strategy is a highly organised process which the bacteria can follow to ensure its survival within the host. Furthermore, knowledge of these mechanisms could provide novel approaches to treatment of periodontal diseases.
KE Sharquie, AA Noaimi, S Adnan, AM Al-Niddawi, WK Aljanabi, American Journal of Dermatology and Venereology, 2020 - Cited by 2
Pharmaceutical care is a patient-centered, outcomes oriented practice that requires the pharmacist to work in concert with the patient and the patient’s other healthcare providers to promote health, to prevent disease, and to assess, monitor, initiate, and modify medication use to assure that drug therapy regimens are safe and effective. In addition, the presence of clinical pharmacists has led to a higher quality of patient education and provision of complete detailed information for patients. In developed countries Pharm D has become the professional degree for practice of Pharmacy. The graduates will be enrolled in a pharmacy residency program; admission to the residency programs is available to Pharm D graduates of an accredit
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Abstract
The aim of this paper is to investigate and discuss the mechanisms of corrosion of epoxy coatings used for potable water tanks. Two distinct types of Jotun epoxy coatings: Tankguard 412 contained polyamine cured epoxy and Penguard HB contained polyamide cured epoxy, were tested and studied using the electrochemical impedance spectroscopic (EIS) method. The porosity of epoxy coatings was determined using EIS method. The obtained results showed that the two epoxy coatings have excellent behavior when applied and tested in potable water of Basrah city. Polyamine is more resistance to water corrosion compared to polyamide curing epoxy and has high impedance values. Microscopic inspection after te
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In the present study, advanced oxidation treatment, the TiO2 /UV/H2O2 process was applied to decolorisation of the reactive yellow dyes in aqueous solution. The UV radiation was carried out with a 6 W low-pressure mercury lamp. The rate of color removal was studied by measuring the absorbency at a characteristic wavelength. The effects of H2O2 dosage, dye initial concentration and pH on decolorisation kinetics in the batch photoreactor were investigated. The highest decolorisation rates were observed (98.8) at pH range between 3 and 7. The optimal levels of H2O2 needed for the process were examined. It appears that high levels of H2O2 could reduce decolori
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We investigated at the optical properties, structural makeup, and morphology of thin films of cadmium telluride (CdTe) with a thickness of 150 nm produced by thermal evaporation over glass. The X-ray diffraction study showed that the films had a crystalline composition, a cubic structure, and a preference for grain formation along the (111) crystallographic direction. The outcomes of the inquiry were used to determine these traits. With the use of thin films of CdTe that were doped with Ag at a concentration of 0.5%, the crystallization orientations of pure CdTe (23.58, 39.02, and 46.22) and CdTe:Ag were both determined by X-ray diffraction. orientations (23.72, 39.21, 46.40) For samples that were pure and those that were doped with
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Given that the Crimean and Congo hemorrhagic fever is one of the deadly viral diseases that occur seasonally due to the activity of the carrier “tick,” studying and developing a mathematical model simulating this illness are crucial. Due to the delay in the disease’s incubation time in the sick individual, the paper involved the development of a mathematical model modeling the transmission of the disease from the carrier to humans and its spread among them. The major objective is to comprehend the dynamics of illness transmission so that it may be controlled, as well as how time delay affects this. The discussion of every one of the solution’s qualitative attributes is included. According to the established basic reproductio
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Background The traditional management of appendicular mass is an initial conservative treatment followed by interval appendectomy. Recently interval appendicectomy has been questioned.
Objective: The purpose of this study was to clarify the need and the role of interval appendicectomy after successful initial conservative treatment.
Method: This is a prospective study conducted in a major hospital in Basra from April 2006 to Septemper2010, included 65 patients with appendicular mass which subsequently proved postinflammmatory (phlegmonous) changes of the appendix were treated conservatively.
Results: Routine interval appendicectomy was not performed and needed after successful treatment in the majority of the patients (84.6%). F
The research aims to estimate missing values using covariance analysis method Coons way to the variable response or dependent variable that represents the main character studied in a type of multi-factor designs experiments called split block-design (SBED) so as to increase the accuracy of the analysis results and the accuracy of statistical tests based on this type of designs. as it was noted in the theoretical aspect to the design of dissident sectors and statistical analysis have to analyze the variation in the experience of experiment )SBED) and the use of covariance way coons analysis according to two methods to estimate the missing value, either in the practical side of it has been implemented field experiment wheat crop in
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Many previous investigations have found quercetin to be a powerful antioxidant and antitumor flavonoid, but its poor bioavailability has limited its use. This current study investigated the effects of two newly synthesized Quercetin Schiff bases containing 2-amino thiadiazole-5-thiol (Q1), and its benzyl derivatives (Q2) on MCF-7 human breast cancer cells. Cell viability and apoptosis were assessed to determine the toxic effects of Q1 and Q2. Cytotoxicity valuation showed that both compounds inhibited MCF-7 cell growth, and lactate dehydrogenase (LDH) activity increased in a dose-dependent aspect compared to the control group. Comet assay results observed that Q1 and Q2 induce more serious DNA damage than the control (untreated cell
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In this work, new Schiff bases of quinazolinone derivatives (Q1-Q5) were synthesized from methyl anthranilate. The synthesis involved three steps. In the first step, methyl anthranilate was reacted with isothiocyanatobenzene, producing the thiourea derivative K1. The second step entailed reacting K1 with hydrazine hydrate, synthesizing 3-amino-2-(phenylamino) quinazolin-4(3H)-one (K2). The third step involved reaction of K2 with various aromatic aldehydes, yielding the Schiff bases derivatives Q1-Q5. The chemical structures of these compounds were identified by FT-IR,1H NMR and 13C NMR spectroscopy. The newly synthesized derivatives (Q1-Q5) were subjected to rigorous evaluation to assess their efficacy as corrosion inhibitors for ca
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