Evaluation of the Synergistic Effect of Amikacin with Cefotaxime against <em>Pseudomonas aeruginosa</em> and Its Biofilm Genes Expression

A total of 100 broiler chickens were examined for the presence of Pseudomonas aeruginosa by standard microbiological techniques. Susceptibility pattern for amikacin and cefotaxime was performed by Kirby-Bauer and microdilution assays. Then, checkerboard titration in trays was applied and FIC was measured to identify the type of interaction between the two antibiotics. The ability of isolates to form in vitro biofilm was detected by two methods, one qualitative (CRA) and the other quantitative (MTP), followed by investigating the effect of each antibiotic alone and in combination on the expression of biofilm genes. The overall isolation percentage of P. aeruginosa was 21%. Resistance to each antibiotic was more than 50%; the range of cefotaxime MIC was 8–512 μg/ml, while amikacin MIC range was 1–64 μg/ml. The FIC index established a synergistic association between tested two drugs in 17 (81%) of isolates and the remaining represent partially synergism. The qualitative technique showed that only 66.6% of the isolates were considered biofilm producers, while the quantitative technique showed that 90.4% of the isolates were biofilm producers. Further to RT-PCR investigation, significant repression against biofilm-forming genes (filC, pelA, and pslA) was observed for the combination of antibiotics when compared with monotherapy

Influence of povidone-iodine on micro-tensile bonding strength to dentin under simulated pulpal pressure

Abstract Background Previous studies had reported that bond strength deteriorate over time following the dentin surface pretreatment with chlorhexidine. Therefore, further investigations are needed to evaluate the effect of other materials such as povidone iodine. The purpose of this study was to investigate the effects of 10% povidone-iodine pretreatment on the resin-dentin micro-tensile bond strength of a single bond adhesive system in permanent teeth over time, and compare it with 2% chlorhexidine. Methods Flat dentin surfaces were prepared in 63 extracted permanent teeth. Teeth were randomly assigned to a 10% povidone-iodine pretreatment, a 2% chlorhexidine pretreatment, or a control group. Composite resin blocks were built up over treated surfaces under pulp pressure simulation. The prepared specimens were assigned to three storage time, 24 h, 1 week, and 2 months. Samples were vertically sectioned to obtain specimens of 0.7 to 1.2 mm2 cross-sectional area. Results No significant reduction of bond strength of povidone iodine group was found among the three storage times (p = 0.477). A significant reduction of bond strength for both chlorhexidine and control groups was found in the three storage times (p <  0.001). Conclusion Povidone iodine pretreatment of etched dentin was effective in reducing the loss of bond strength over time, while the chlorhexidine pretreatment and negative control showed significant deterioration in micro-tensile bond strength over time in permanent teeth

Mobile Colistin Resistance Determinants among Enterobacteriaceae Isolated from Different Poultry Species

Antimicrobial resistance (AMR) is a global threat that requires serious attention, particularly when it is developed against colistin, which is considered one of the ‘last resort’ antibiotics in the poultry industry. This study aimed to investigate the AMR profile of Enterobacteriaceae isolates from different poultry species, detect colistin resistance and investigate the existence of&nbsp;mcr&nbsp;genes in multi and extreme-resistant isolates. A total of 233 birds, chickens, ducks, turkeys, and quails, of various ages and breeds were collected from several localities of the Sharkia governorate and analyzed bacteriologically. The disc diffusion and E-test assays scrutinized the patterns of antibiotic, multidrug-resistant (MDR), and colistin resistance. The PCR assay was carried out to detect the&nbsp;mcr&nbsp;variants. Bacteriological examination revealed the incidence of 42.3% (99/233) of different Enterobacteriaceae members with a high predominance of&nbsp;E. coli,&nbsp;Salmonella,&nbsp;and Klebsiella species. Disc diffusion findings disclosed that 78.78% of isolates were resistant to colistin but E-test detected 19.19% only. Observed colistin resistance was strongly linked to the distribution of plasmid&nbsp;mcr-operons. The&nbsp;mcr&nbsp;1, 2, 3, 4, and 7.1 genes were detected in 42.1, 63.15, 57.89, 52.63, and 47.36% of the phenotypic resistant isolates, and about 36.84% harbored at least four&nbsp;mcr&nbsp;clusters. However, the&nbsp;mcr5&nbsp;gene was not discovered. The statistical assessment revealed a significant association between colistin resistance and MDR (p≤0.05). Moreover, there was a strong correlation between MCR-abundance and doxycycline, fosfomycin, beta-lactams, imipenem, and tobramycin resistances. In conclusion, this study highlights the alarming occurrence of colistin-resistant Enterobacteriaceae in various poultry aspects. An urgent strategy must be adopted to avert the spread of this phenomenon

Food and environmental parasitology in Canada:A network for the facilitation of collaborative research

Parasitic diseases are of considerable public health significance in Canada, particularly in rural and remote areas. Food- and water-borne parasites contribute significantly to the overall number of parasitic infections reported in Canada. While data on the incidence of some of these diseases are available, knowledge of the true burden of infection by the causative agents in Canadians is somewhat limited. A number of centers of expertise in Canada study various aspects of parasitology, but few formal societies or networks of parasitologists currently exist in Canada, and previously none focused specifically on food or environmental transmission. The recently established Food and Environmental Parasitology Network (FEPN) brings together Canadian researchers, regulators and public health officials with an active involvement in issues related to these increasingly important fields. The major objectives of the Network include identifying research gaps, facilitating discussion and collaborative research, developing standardized methods, generating data for risk assessments, policies, and guidelines, and providing expert advice and testing in support of outbreak investigations and surveillance studies. Issues considered by the FEPN include contaminated foods and infected food animals, potable and non-potable water, Northern and Aboriginal issues, zoonotic transmission, and epidemiology