Distribution pattern of antibiotic resistance genes in Escherichia coli isolated from colibacillosis cases in broiler farms of Egypt

Background and Aim: Multidrug resistance (MDR) of Escherichia coli has become an increasing concern in poultry farming worldwide. However, E. coli can accumulate resistance genes through gene transfer. The most problematic resistance mechanism in E. coli is the acquisition of genes encoding broad-spectrum β-lactamases, known as extended-spectrum β-lactamases, that confer resistance to broad-spectrum cephalosporins. Plasmid-mediated quinolone resistance genes (conferring resistance to quinolones) and mcr-1 genes (conferring resistance to colistin) also contribute to antimicrobial resistance. This study aimed to investigate the prevalence of antimicrobial susceptibility and to detect β-lactamase and colistin resistance genes of E. coli isolated from broiler farms in Egypt. Materials and Methods: Samples from 938 broiler farms were bacteriologically examined for E. coli isolation. The antimicrobial resistance profile was evaluated using disk diffusion, and several resistance genes were investigated through polymerase chain reaction amplification. Results: Escherichia coli was isolated and identified from 675/938 farms (72%) from the pooled internal organs (liver, heart, lung, spleen, and yolk) of broilers. Escherichia coli isolates from the most recent 3 years (2018–2020) were serotyped into 13 serotypes; the most prevalent serotype was O125 (n = 8). The highest phenotypic antibiotic resistance profiles during this period were against ampicillin, penicillin, tetracycline, and nalidixic acid. Escherichia coli was sensitive to clinically relevant antibiotics. Twenty-eight selected isolates from the most recent 3 years (2018–2020) were found to have MDR, where the prevalence of the antibiotic resistance genes ctx, tem, and shv was 46% and that of mcr-1 was 64%. Integrons were found in 93% of the isolates. Conclusion: The study showed a high prevalence of E. coli infection in broiler farms associated with MDR, which has a high public health significance because of its zoonotic relevance. These results strengthen the application of continuous surveillance programs

Forskolin Modulate Silent Information Regulator 1 (SIRT1) gene Expression and Halts Experimentally-Induced Acute Kidney Injury

Acute kidney injury is a very serious medical condition; change of the normal physiological oxidant-antioxidant balance has been reported as a major cause for renal injury. Silent information regulator 1 (Sirt1) is a nicotinamide adenine dinucleotide- (NAD+-) dependent deacetylase that has nephro-protective effect against ischemia or injury by toxic substances by increasing cell resistance to oxidative stress. Forskolin is derived from plant Coleus forskohlii and has been used to treat the heart disease, hypertension, diabetes and asthma. This study was done to investigate the possible protective role of forskolin against glycerol- induced acute nephrotoxicity and also to study the possible mechanisms underlying this action. In the present study rats were randomly divided into four groups. Rats in the control group received distilled water orally for 15 days, four days before scarification they received half the dose of saline (10 ml/kg) in each hind limb muscle; rats in the FSK group received 500 mg/kg per day, orally for 15 days; those in the glycerol group (AKI) received half the dose of glycerol (10 ml/kg, 50% v/v in sterile saline) in each hind limb muscle; rats in the FSK + glycerol (AKI) group received FSK 500 mg/kg per day, orally 12 days before glycerol injection and continued for three days after glycerol administration with a total period of 15 days, all rats were deprived of water for 24 h before glycerol injection. Parameters tested in this study were kidney function tests (urea, creatinine), oxidative stress parameters (MDA, GST), anti-inflammatory marker (TNF-α), anti-apoptotic marker (caspase-3), SIRT gene expression detected by RT-PCR and histopathlogical study. Results: Glycerol administration caused significant increase in all tested parameters except SIRT gene expression which decreased with glycerol administration. Pretreatment with forskolin caused significant decrease of levels of urea, creatinine, MDA, TNF-α and also decreased activity of caspase-3 and GST, with significant improvement of SIRT expression. Histopathological examination revealed that the glycerol caused severe kidney damage in the form of hemorrhage, inflammatory cell infiltration and intra-tubular cast formation compared to normal renal histology and architecture of the control and forskolin groups. Forskolin pretreatment of glycerol induced AKI caused marked improvement of histological picture which exhibited mild edema and tubular vacuolization compared to the control group. In conclusion the possible beneficial effect of forskolin in protection against nephrotoxicity is due to its ability to modulate the disrupted expression of SIRT gene as well as its anti-oxidant, anti-inflammatory and anti-apoptotic properties. This may open a new therapeutic window for renal patient

Virulence Range and New Pathological Pictures of Salmonella enteridits and Salmonella typhimurium Isolated from Ducklings in Experimental Infected Chicks

Salmonellosis is a major global pathogen in the poultry industry and is a significant public health concern. Ducks are known to be carriers of Salmonella. Therefore, monitoring salmonellosis is the most important strategy for preventing the disease. An experimental design was planned to study the pathogenicity of two Salmonella strains. One hundred and fifty chicks were divided into three groups; group one was inoculated with the Salmonella enteritidis strain, group two was inoculated with the Salmonella typhimurium strain, and group three was UN inoculated. Symptoms, postmortem lesions and mortality rate were recorded. The chick growth performance parameters were also determined. Using ANOVA for statistical analysis, there was a significant difference in body weight, body gain, feed consumption, and feed conversion ratio between the two infected groups and the blank group (uninoculated group). In this study, the prevalence of Salmonella enteritidis was (1.73%) and Salmonella typhimurium (0.43%) in imported ducklings in Egypt. Both Salmonella strains were subjected to an antimicrobial sensitivity test. It showed that Salmonella enteritidis had a 60% antimicrobial resistance profile and Salmonella typhimurium had a 20% antimicrobial resistance profile. Furthermore, genotypic characterization was performed and the seven virulence genes(stn, avrA, sopB, ompF, invA, Mgtc, Ssaq) were found. New pathological lesions of Salmonella infection were discovered, such as skull hemorrhage at 3 days and 6 days of age, and a liver similar to a button shape in necropsied infected chicks with Salmonella typhimurium at 21 days of age. Furthermore, hemorrhagic spots were observed on the duodenum. In the presence of Salmonella, Clostridium perferingens was discovered in a bacteriological investigation of duodenal lesions samples from infected chicks. At 30 days of age, administration of acetic acid (1%) as an alternative tool for controlling Salmonella. In conclusion, salmonellosis is a risk factor for necrotic enteritis, and using acetic acid to eliminate salmonella infection is insufficient

Novel Antiviral and Antibacterial Durable Polyester Fabrics Printed with Selenium Nanoparticles (SeNPs)

The COVID-19 pandemic has clearly shown the importance of developing advanced protective equipment, and new antiviral fabrics for the protection and prevention of life-threatening viral diseases are needed. In this study, selenium nanoparticles (SeNPs) were combined with polyester fabrics using printing technique to obtain multifunctional properties, including combined antiviral and antibacterial activities as well as coloring. The properties of the printed polyester fabrics with SeNPs were estimated, including tensile strength and color fastness. Characterization of the SeNPs was carried out using TEM and SEM. The results of the analysis showed good uniformity and stability of the particles with sizes range from 40–60 nm and 40–80 nm for SeNPs 25 mM and 50 mM, respectively, as well as uniform coating of the SeNPs on the fabric. In addition, the SeNPs—printed polyester fabric exhibited high disinfection activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with an inhibition percentage of 87.5%. Moreover, a toxicity test of the resulting printed fabric revealed low cytotoxicity against the HFB4 cell line. In contrast, the treated fabric under study showed excellent killing potentiality against Gram-positive bacteria (Bacillus cereus) and Gram-negative bacteria (Pseudomonas aeruginosa, Salmonella typhi, and Escherichia coli). This multifunctional fabric has high potential for use in protective clothing applications by providing passive and active protection pathways

Tigecycline and Gentamicin-Combined Treatment Enhances Renal Damage: Oxidative Stress, Inflammatory Reaction, and Apoptosis Interplay

Although the combination of antibiotics is generally well-tolerated, they may have nephrotoxic effects. This study investigated whether tigecycline (TG) and gentamicin (GM) co-administration could accelerate renal damage. Male Wistar rats were randomly divided into six experimental groups: the control, TG7 (tigecycline, 7 mg/kg), TG14 (tigecycline, 14 mg/kg), GM (gentamicin, 80 mg/kg), TG7+GM, and TG14+GM groups. The combination of TG and GM evoked renal damage seen by the disruption of kidney function tests. The perturbation of renal tissue was mainly confounded to the TG and GM-induced oxidative damage, which was exhibited by marked increases in renal MDA (malondialdehyde) along with a drastic reduction in GSH (reduced-glutathione) content and CAT (catalase) activity compared to their individual treatments. More obvious apoptotic events and inflammation were also revealed by elevating the annexin-V and interleukin-6 (IL-6) levels, aside from the upregulation of renal PCNA (proliferating cell nuclear antigen) expression in the TG and GM concurrent treatment. The principal component analysis indicated that creatinine, urea, annexin-V, IL-6, and MDA all played a role in discriminating the TG and GM combined toxicity. Oxidative stress, inflammatory response, and apoptosis were the key mechanisms involved in this potentiated toxicity