Quorum sensing inhibitory activity of sub-inhibitory concentrations of β-lactams

Introduction: The virulence factors of Pseudomonas aeruginosa are under the control of quorum sensing (QS) signals. Hence, interference with QS prevents its pathogenesis.Objective: The aim of the present research is to assess the influence of some β-lactam antibiotics on cell communication and the release of different virulence factors.Methods: The minimal inhibitory concentrations of ceftazidime, cefepime and imipenem were evaluated by microbroth dilution method. The effect of sub-inhibitory concentration of the tested antibiotics on QS signals was investigated using reporter strain assay. In addition, different virulence factors (elastase, protease, pyocyanin and hemolysin) were estimated in the presence of their sub-inhibitory concentrations.Results: Low concentrations of ceftazidime, cefepime and imipenem caused significant elimination of the QS signals 3OHC12- HSL and C4-HSL up to 1/20 MIC. Furthermore, low concentrations of the tested antimicrobials suppressed virulence factors elastase and hemolysin. Moreover, 1/20 of their MICs reduced elastase, protease, pyocyanin and hemolysin.Conclusion: Utilization of β-lactam antibiotics at low concentrations could be an effective approach for prevention and treatment of P. aeruginosa infection.Keywords: Quorum sensing inhibition, β-lactams, Pseudomonas aeruginos

Video streaming in urban vehicular environments: Junction-aware multipath approach

© 2019 by the authors. Licensee MDPI, Basel, Switzerland. In multipath video streaming transmission, the selection of the best vehicle for video packet forwarding considering the junction area is a challenging task due to the several diversions in the junction area. The vehicles in the junction area change direction based on the different diversions, which lead to video packet drop. In the existing works, the explicit consideration of different positions in the junction areas has not been considered for forwarding vehicle selection. To address the aforementioned challenges, a Junction-Aware vehicle selection for Multipath Video Streaming (JA-MVS) scheme has been proposed. The JA-MVS scheme considers three different cases in the junction area including the vehicle after the junction, before the junction and inside the junction area, with an evaluation of the vehicle signal strength based on the signal to interference plus noise ratio (SINR), which is based on the multipath data forwarding concept using greedy-based geographic routing. The performance of the proposed scheme is evaluated based on the Packet Loss Ratio (PLR), Structural Similarity Index (SSIM) and End-to-End Delay (E2ED) metrics. The JA-MVS is compared against two baseline schemes, Junction-Based Multipath Source Routing (JMSR) and the Adaptive Multipath geographic routing for Video Transmission (AMVT), in urban Vehicular Ad-Hoc Networks (VANETs)

Quorum sensing inhibitory activity of sub-inhibitory concentrations of \u3b2-lactams

Introduction: The virulence factors of Pseudomonas aeruginosa are under the control of quorum sensing (QS) signals. Hence, interference with QS prevents its pathogenesis. Objective: The aim of the present research is to assess the influence of some \u3b2-lactam antibiotics on cell communication and the release of different virulence factors. Methods: The minimal inhibitory concentrations of ceftazidime, cefepime and imipenem were evaluated by microbroth dilution method. The effect of sub-inhibitory concentration of the tested antibiotics on QS signals was investigated using reporter strain assay. In addition, different virulence factors (elastase, protease, pyocyanin and hemolysin) were estimated in the presence of their sub-inhibitory concentrations. Results: Low concentrations of ceftazidime, cefepime and imipenem caused significant elimination of the QS signals 3OHC12-HSL and C4-HSL up to 1/20 MIC. Furthermore, low concentrations of the tested antimicrobials suppressed virulence factors elastase and hemolysin. Moreover, 1/20 of their MICs reduced elastase, protease, pyocyanin and hemolysin. Conclusion: Utilization of \u3b2-lactam antibiotics at low concentrations could be an effective approach for prevention and treatment of P. aeruginosa infection

Clinical and genetic assessment of pediatric patients with Gaucher’s disease in Upper Egypt

Background: Gaucher’s disease (GD) is an autosomal recessive genetic disorder that results from pathogenic mutations of GBA gene encoding the enzyme glucocerebrosidase (acid b-glucosidase). Of the approximately 300 mutations associated with GD, 4 accounts for the majority of mutations seen in GD patients: N370S, L444P, 84 GG and IVS2+1.Aim: Establishing and providing, clinical and molecular backgrounds of pediatric patients with GD in Upper Egypt.Subjects and methods: The present study is a cross sectional study, carried out on 26 pediatric patients with GD. They were recruited from the pediatric outpatient clinics and inpatients Pediatric departments of Assiut and Qena University hospitals, Upper Egypt. Clinical evaluation and mutation analysis using commercially available strip assay kit after PCR amplification of the target gene were done for all included GD patients.Results: Consanguinity between patients’ parents was present in 73.1% of the included patients. 76.9% of included patients were of type 1 GD, while 23.1% were of type 3 GD and none of our patients was classified as type 2 GD. The main frequent clinical presentations of GD in this study were hepatosplenomegaly (88.5%); pallor (76.9%); abdominal distension (61.5%) and musculoskeletal involvement (37.1%). Neurological abnormalities of type 3 GD included in this study were squint, seizures and delayed mental development. Five different genotypes were detected, homozygous for the mutation L444P, homozygous for the mutation N370S, heterozygous for the mutations N370S and rec Ncil, heterozygous for IVS2 +1 and rec NciI, heterozygous for L444P and IVS2 +1. Conclusions: Non-neuropathic type 1 and type 3 GD were the only clinical types found in the present study. The most common mutant alleles found in this study were L444P and N370S

Hepatitis B virus (HBV) genotypes in Egyptian pediatric cancer patients with acute and chronic active HBV infection

<p>Abstract</p> <p>Background</p> <p>There are eight genotypes of hepatitis B virus (A-H) and subgenotypes are recognized. Genotyping can be accomplished based on a partial sequence of HBV genome such as the pre-S or S gene. Several methods have been developed and used for HBV genotyping. This study was undertaken to determine the HBV genotypes in Egyptian pediatric cancer patients with acute and chronic liver disease.</p> <p>Methods</p> <p>HBV genotypes were determined in 22 patients who had acute forms of liver disease (AH) and in 48 patients with chronic active hepatitis (CAH). A type-specific primer based the nested-PCR method was employed in the HBV genotyping.</p> <p>Results</p> <p>This study showed that HBV infections in pediatric cancer patients are attributed predominantly to viral genotypes D and B that constituted 37.1% and 25.7%, respectively of the total infections. In addition, there was a relatively high prevalence of mixed infections of 15.7% among the studied group especially mixed A/D genotype infections. Genotype D was found significantly more often in patients with CAH than in patients with AH [23/48(47.9%) <it>v </it>3/22 (13.6%)].</p> <p>Conclusion</p> <p>These findings show the distribution of HBV A-D genotypes in pediatric cancer Egyptian patients. Furthermore, our results indicate a markedly high prevalence of mixed A/D genotype infections in subjects with CAH and a possible association of mixed infections with the severity of liver diseases.</p

Nanotechnology in Head and Neck Cancer: The Race Is On

Rapid advances in the ability to produce nanoparticles of uniform size, shape, and composition have started a revolution in the sciences. Nano-sized structures herald innovative technology with a wide range of potential therapeutic and diagnostic applications. More than 1000 nanostructures have been reported, many with potential medical applications, such as metallic-, dielectric-, magnetic-, liposomal-, and carbon-based structures. Of these, noble metallic nanoparticles are generating significant interest because of their multifunctional capacity for novel methods of laboratory-based diagnostics, in vivo clinical diagnostic imaging, and therapeutic treatments. This review focuses on recent advances in the applications of nanotechnology in head and neck cancer, with special emphasis on the particularly promising plasmonic gold nanotechnology

An Extended Investigation of High-Level Natural Radioactivity and Geochemistry of Neoproterozoic Dokhan Volcanics: A Case Study of Wadi Gebeiy, Southwestern Sinai, Egypt

High-level natural radioactivity, geochemical, geological, and radiological hazard assessment of the poorly investigated Wadi Gebeiy Dokhan volcanics rocks are discussed. Wadi Gebeiy Dokhan volcanics are located in Southwestern Sinai, Egypt, covering an area of ~1.3 km2. Dokhan volcanics rocks are represented by porphyritic dacite. Geochemically, they have medium-k characters and originate from calc-alkaline magma within a volcanics arc environment. Along the fault plane striking NNE-SSW, and at its intersection with the NW-SE fault plane, altered Dokhan volcanics occur with high radioactive anomalies. Radiological parameters (absorbed dose rate, radium equivalent, activity annual effective dose, external and internal hazard indices) are used to evaluate their suitability as an ornamental stone. Except for the absorbed dose rate, all the radiological hazard indices show that unaltered Dokhan volcanics can be used as an ornamental stone. Controversially, the applied radiological indices reveal that altered Dokhan volcanics have a higher content than the recommended values of UNSCEAR, reflecting their risk on human organs. © 2022 by the authors.H.M.H.Z. is funded by a scholarship under the Joint Executive Program between Egypt and Russia

Effect of root-knot nematode and two species of crown gall on antioxidant activity of grape leaves

Agrobacterium tumefaciens and Agrobacterium vitis significantly reduced the entire criteria (galls, embedded stages, final population, Pf/Pi and egg production) of the root-knot nematode, Meloidogyne incognita, when they were in concomitance with grape (Vitis vinifera var) superior roots. Greater suppression in such criteria was observed with high inoculum levels (5X10 7 cfu/pot) than with lower (2.5X10 7 cfu/pot) ones. All treatments resulted in the increase of leaves contents of H 2 O 2 and lipid peroxidation (TBARS) dramatically, which were considered the most damaging stresses in plant cells. The contents of AsA, GSH, TPH and PAL specific activity increased as a strongly antioxidant defense compound against induced oxidative damage. In addition, the increase in the activity of various antioxidant defense specific enzymes (SOD, APX, CAT and GST) represented the protective activity used to counteract the oxidative injury promoted by nematode and nematode-bacteria infections. The rate of the chemical increase was significantly higher in interaction treatments than in the leaves of plants treated singly with M. incognita. Moreover, higher inoculum levels resulted in higher values of the measured chemicals. Symptoms appearance at low levels of nematode and bacterial treatments were significantly preceded by significant induction of AsA, GSH and TPH contents, and APX, CAT, SOD, GST and PAL activities in grape leaves. However, under high levels of nematode and bacteria, an obvious depletion at all non-antioxidants enzymes&apos; levels and antioxidants enzymes&apos; activities was observed. It is supposed that stimulated antioxidative processes contributed to the suppression of necrotic symptom development in grape leaves depending on the level of pathogen inoculum

Anthracnose Disease (Colletotrichum sp.) Affecting Olive Fruit Quality and Its Control in Egypt

Abstract Olive anthracnose is the most important fungal disease of olive fruits worldwide. It occurs in humid olive-growing areas of many countries and causes heavy yield losses and lowering of oil quality. Colletotrichum acutatum was isolated and identified from rotten olive fruits. Pathogenicity test of C. acutatum was confirmed. It was found to be decreased all physical characteristics measured i.e. weight (gm), length (mm), diameter (mm) and volume (ml3). Also, C. acutatum was found to decrease the oil content of the fruits, while increasing their total titratable acidity and moisture content. Physiological studies resulted that, the highest growth rate and sporulation was recorded with PDA medium, PH 6.5 and Light/dark cycle treatments. Hot water treatments at 45, 50 and 55°C were able to decreased spore viability of C. acutatum compared with untreated (control). The best treatment of hot water was recorded with 55°C. in vivo. Also, hot water treatment at 55°C was successful in reducing the percentage of anthracnose disease incidence on olive fruits in vitro. All tested alternative substrates i. e. Ascorbic acid, Benzoic acid, potassium sorbate and citric acid used were able to reduce the linear growth rate of C. acutatum in vitro. Benzoic acid was found to be the best alternative substrate used which gave completely fruit protection (hundred of reduction percent) followed by Ascorbic acid, Potassium sorbate and Citric acid. This is thought to be the first report of anthracnose disease of olive fruits in Egypt

Molecular identification of adenoviruses associated with respiratory infection in Egypt from 2003 to 2010.

BACKGROUND: Human adenoviruses of species B, C, and E (HAdV-B, -C, -E) are frequent causative agents of acute respiratory infections worldwide. As part of a surveillance program aimed at identifying the etiology of influenza-like illness (ILI) in Egypt, we characterized 105 adenovirus isolates from clinical samples collected between 2003 and 2010. METHODS: Identification of the isolates as HAdV was accomplished by an immunofluorescence assay (IFA) and confirmed by a set of species and type specific polymerase chain reactions (PCR). RESULTS: Of the 105 isolates, 42% were identified as belonging to HAdV-B, 60% as HAdV-C, and 1% as HAdV-E. We identified a total of six co-infections by PCR, of which five were HAdV-B/HAdV-C co-infections, and one was a co-infection of two HAdV-C types: HAdV-5/HAdV-6. Molecular typing by PCR enabled the identification of eight genotypes of human adenoviruses; HAdV-3 (n = 22), HAdV-7 (n = 14), HAdV-11 (n = 8), HAdV-1 (n = 22), HAdV-2 (20), HAdV-5 (n = 15), HAdV-6 (n = 3) and HAdV-4 (n = 1). The most abundant species in the characterized collection of isolates was HAdV-C, which is concordant with existing data for worldwide epidemiology of HAdV respiratory infections. CONCLUSIONS: We identified three species, HAdV-B, -C and -E, among patients with ILI over the course of 7 years in Egypt, with at least eight diverse types circulating