Antibiotic resistance genes (ARGs) transfer rapidly among bacterial species all over the world contributing to the aggravation of antibiotic resistance crisis. Antibiotics at sub-inhibitory ...concentration induce horizontal gene transfer (HRT) between bacteria, especially through conjugation. The role of common non-antibiotic pharmaceuticals in the market in disseminating antibiotic resistance is not well studied. In this work, we indicated the effect of some commonly used non-antibiotic pharmaceuticals including antiemetic (metoclopramide HCl) and antispasmodics (hyoscine butyl bromide and tiemonium methyl sulfate) on the plasmid-mediated conjugal transfer of antibiotic resistance genes between pathogenic E. coli in the gastric intestinal tract (GIT). Broth microdilution assay was used to test the antibacterial activity of the tested non-antibiotic pharmaceuticals. A conjugation mating system was applied in presence of the studied non-antibiotic pharmaceuticals to test their effect on conjugal transfer frequency. Plasmid extraction and PCR were performed to confirm the conjugation process. Transmission electron microscopy (TEM) was used for imaging the effect of non-antibiotic pharmaceuticals on bacterial cells. No antibacterial activity was reported for the used non-antibiotic pharmaceuticals. Plasmid-mediated conjugal transfer between isolates was induced by metoclopramide HCl but suppressed by hyoscine butyl bromide. Tiemonium methylsulfate slightly promoted conjugal transfer. Aggregation between cells and periplasmic bridges was clear in the case of metoclopramide HCl while in presence of hyoscine butyl bromide little affinity was observed. This study indicates the contribution of non-antibiotic pharmaceuticals to the dissemination and evolution of antibiotic resistance at the community level. Metoclopramide HCl showed an important role in the spread of antibiotic resistance.
Pseudomonas aeruginosa is an opportunistic pathogen that can cause a variety of diseases especially in the hospital environment. However, this pathogen also exhibits antimicrobial activity against ...Gram-positive bacteria and fungi. This study aimed to characterize different virulence factors, secreted metabolites and to study their role in the suppression of Candida growth. Fifteen P. aeruginosa isolates were tested for their anticandidal activity against 3 different Candida spp. by the cross-streak method. The effect on hyphae production was tested microscopically using light and scanning electron microscopy (SEM). Polymerase chain reaction was used in the detection of some virulence genes. Lipopolysaccharide profile was performed using SDS-polyacrylamide gel stained with silver. Fatty acids were analyzed by GC-MS as methyl ester derivatives. It was found that 5 P. aeruginosa isolates inhibited all tested Candida spp. (50-100% inhibition), one isolate inhibited C. glabrata only and 3 isolates showed no activity against the tested Candida spp. The P. aeruginosa isolates inhibiting all Candida spp. were positive for all virulence genes. GC-Ms analysis revealed that isolates with high anticandidal activity showed spectra for several compounds, each known for their antifungal activity in comparison to those with low or no anticandidal activity. Hence, clinical isolates of P. aeruginosa showed Candida species-specific interactions by different means, giving rise to the importance of studying microbial interaction in polymicrobial infections and their contribution to causing disease.
Silver is a potent antimicrobial agent against a variety of microorganisms and once the element has entered the bacterial cell, it accumulates as silver nanoparticles with large surface area causing ...cell death. At the same time, the bacterial cell becomes a reservoir for silver. This study aims to test the microcidal effect of silver-killed
O104: H4 and its supernatant against fresh viable cells of the same bacterium and some other species, including
O157: H7, Multidrug Resistant (MDR)
and Methicillin Resistant
(MRSA). Silver-killed bacteria were examined by Transmission Electron Microscopy (TEM). Agar well diffusion assay was used to test the antimicrobial efficacy and durability of both pellet suspension and supernatant of silver-killed
O104:H4 against other bacteria. Both silver-killed bacteria and supernatant showed prolonged antimicrobial activity against the tested strains that extended to 40 days. The presence of adsorbed silver nanoparticles on the bacterial cell and inside the cells was verified by TEM. Silver-killed bacteria serve as an efficient sustained release reservoir for exporting the lethal silver cations. This promotes its use as a powerful disinfectant for polluted water and as an effective antibacterial which can be included in wound and burn dressings to overcome the problem of wound contamination.
Introduction: The emergence of multidrug-resistant (MDR) E. coli has developed worldwide; therefore, the use of antibiotic combinations may be an effective strategy to target resistant bacteria and ...fight life-threatening infections. The current study was performed to evaluate the in vitro and in vivo efficacy of amikacin and imipenem alone and in combination against multidrug-resistant E. coli. Methods: The combination treatment was assessed in vitro using a checkerboard technique and time- killing curve and in vivo using a peritonitis mouse model. In resistant isolates, conventional PCR and quantitative real-time PCR techniques were used to detect the resistant genes of Metallo-beta-lactamase gene Imipenemase (bla-IMP) and aminoglycoside 6′-N-acetyltransferase (aac (6′)-Ib). Scanning electron microscopy was used to detect the morphological changes in the resistant isolates after treatment with each drug alone and in combination. In vitro and in vivo studies showed a synergistic effect using the tested antibiotic combinations, showing fractional inhibitory concentration indices (FICIs) of <=0.5. Regarding the in vivo study, combination therapy indicated a bactericidal effect after 24 h. E. coli isolates harboring the resistant genes Metallo-beta-lactamase gene Imipenemase (bla-IMP) and aminoglycoside 6′-N-acetyltransferase (aac (6′)-Ib) represented 80% and 66.7%, respectively, which were mainly isolated from wound infections. The lowest effect on Metallo-beta-lactamase gene Imipenemase (bla-IMP) and aminoglycoside 6′-N-acetyltransferase (aac (6′)-Ib) gene expression was shown in the presence of 0.25 × MIC of imipenem and 0.5 × MIC of amikacin. The scanning electron microscopy showed cell shrinkage and disruption in the outer membrane of E. coli in the presence of the antibiotic combination. Amikacin and imipenem combination can be expected to be effective in the treatment and control of serious infections caused by multidrug-resistant (MDR) E. coli and the reduction in bacterial resistance emergence.
Escherichia coli serotype O157: H7 and E. coli O104: H4 are well known foodborne pathogens causing sever enteric illness. Using bacteriophages as biocontrol agents of some foodborne pathogens and ...multidrug-resistant (MDR) bacteria has a great attention nowadays. This study aims to test the effect of cocktail phages on the growth of some foodborne pathogens and MDR E. coli. Routine conventional PCR was used to confirm the identification of E. coli isolates. Double-layered culture technique was used to isolate phages from sewage water. Morphology of bacteriophage was described using transmission electron microscopy, and spot test was performed to determine host range of the phage cocktail. Phage cocktail of Siphoviridae and Podoviridae family infecting E. coli O157: H7, E. coli O104: H4 and untypeable E. coli (neither O157 nor O104) has been isolated from sewage water. Phage cocktail showed both lytic and lysogenic activity. Lytic activity was observed against E. coli O157: H7, E. coli O104: H4 isolates, Staphylococcus. aureus ATCC6538 and Pseudomonas aeruginosa ATCC 10145, while the lysogenic activity was observed against the untypeable strain. The tested phage cocktail showed a promising inhibitory action on E. coli O157: H7 and O104: H4, S. aureus ATCC6538 and P. aeruginosa ATCC 10145, suggesting the possibility of its use as a biocontrol tool or as natural food preservatives for many food products.
Impaired renal functions have been reported with Hepatitis E virus (HEV) infections, especially with genotypes 3 and 4. These complications were reported during the acute and chronic phases of ...infection. HEV genotype 1 causes acute infection, and the effect of HEV-1 infections on renal functions is not known. We examined the kidney function parameters in the serum of HEV-1 patients (AHE, n = 31) during the acute phase of infection. All of the included patients developed an acute self-limiting course of infection, without progression to fulminant hepatic failure. We compared the demographic, laboratory, and clinical data between AHE patients with normal kidney function parameters and those with abnormal renal parameters. Out of 31 AHE patients, 5 (16%) had abnormal kidney function tests (KFTs) during the acute phase of infection. Three patients had abnormal serum urea and creatinine, and two patients had either abnormal urea or creatinine. Four out of five patients had an estimated glomerular filtration rate (eGFR) below 60 mL/min/1.73 m
. AHE patients with abnormal KFTs were older and had a lower level of albumin, but a slightly elevated alanine transaminase (ALT) compared to AHE patients with normal KFTs. There were no significant differences between the two groups in terms of age, sex, liver transaminase levels, and the viral load. Similarly, the clinical presentations were comparable in both groups. Interestingly, these KFTs in patients with abnormal renal parameters returned to normal levels at the recovery. The serum creatinine level was not correlated with patients' age or liver transaminase levels, but it was significantly negatively correlated with albumin level. In conclusion, this study is the first report that evaluated KFTs in patients during the acute phase of HEV-1 infections. Impaired KFTs in some AHE patients resolved at convalescence. KFTs and renal complications should be monitored during HEV-1 infections.
Nosocomial infections mainly are due to inefficient cleaning in association with the uncontrollable prescription of antimicrobials resulting in the emergence of multi-drug resistant pathogens in the ...hospital environment. Objectives:The study aims to evaluate the impact of the implementation of culture-guided antibiotic policy with strict infection control strategies on the occurrence of nosocomial infections and the resistance pattern ofthe isolated clinical and environmental pathogens. The study was done in 2 periods. Firstly, (August 2016 – April 2017), routine disinfection procedures and the applied antibiotic policy were evaluated. Secondly, according to the results a new antibiotic policy depending on the culture sensitivity results were implemented starting from June 2017 to February 2018 in association with strict infection control practices. As a result of this intervention, A change in the type of the isolated microorganisms was observed.Antibiotic resistance was decreased. Mortality rate was reduced from 14.1% to 9.5% of neonates with nosocomial infections, the number of the prescribed antibiotics didn’t exceed 4 antibiotics decreasing the overall cost for neonates’ therapy during their hospital stay. Each hospital should have its own antibiotic policy with the application of strict infection control strategies for the control of nosocomial infection.
can cause intestinal and extra-intestinal infections which ranged from mild to life-threatening infections. The severity of infection is a product of many factors including virulence properties and ...antimicrobial resistance.
To determine the antibiotic resistance pattern, the distribution of virulence factors and their association with one another and with some selected resistance genes.
Virulence properties were analyzed phenotypically while antimicrobial susceptibility was tested by Kirby-Bauer agar disc diffusion method. In addition, 64
isolates were tested for 6 colicin genes,
virulence genes and
, and
resistance genes by polymerase chain reaction (PCR).
Extra-intestinal pathogenic
isolated from urine and blood samples represented a battery of virulence factors and resistance genes with a great ability to produce biofilm. Also, a significant association (P<0.05) among most of the tested colicin, virulence and resistance genes was observed. The observed associations indicate the importance and contribution of the tested factors in the establishment and the progress of infection especially with
(ExPEC) which is considered a great challenging health problem.
There is a need for studying how to control these factors to decrease the rate and the severity of infections. The relationship between virulence factors and resistance genes is complex and needs more studies that should be specific for each area.
Introduction: Escherichia (E.) coli can cause intestinal and extra-intestinal infections which ranged from mild to life-threatening infections. The severity of infection is a product of many factors ...including virulence properties and antimicrobial resistance. Objectives: To determine the antibiotic resistance pattern, the distribution of virulence factors and their association with one another and with some selected resistance genes. Methods: Virulence properties were analyzed phenotypically while antimicrobial susceptibility was tested by Kirby-Bauer agar disc diffusion method. In addition, 64 E. coli isolates were tested for 6 colicin genes, fimH, hlyA, traT, csgA, crl virulence genes and bla.sub.-CTX-M-15, bla.sub.-oxa-2, and bla.sub.-oxa-10 resistance genes by polymerase chain reaction (PCR). Results: Extra-intestinal pathogenic E. coli isolated from urine and blood samples represented a battery of virulence factors and resistance genes with a great ability to produce biofilm. Also, a significant association (P<0.05) among most of the tested colicin, virulence and resistance genes was observed. The observed associations indicate the importance and contribution of the tested factors in the establishment and the progress of infection especially with Extra-intestinal E. coli (ExPEC) which is considered a great challenging health problem. Conclusion: There is a need for studying how to control these factors to decrease the rate and the severity of infections. The relationship between virulence factors and resistance genes is complex and needs more studies that should be specific for each area. Keywords: E. coli, virulence, resistance, colicin genes, ESBL, bla.sub.-CTX-M-15, bla.sub.-oxa-2, bla.sub.-oxa-10
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