This study was conducted to determine the prevalence rate of VTEC in slaughtered sheep and goats and to evaluate the contamination rate of VTEC in slaughterhouses and butchers' shops in southern Jordan. 201 E. coli isolates from animals' faecal samples and 33 E. coli isolates from slaughterhouse/butcher shop samples were characterized by multiplex PCR (mPCR) reaction for detection of stx1, stx2, eae A and E-hly A virulent genes. Twenty-six virulent E. coli isolates were characterized by mPCR to seven different virulent patterns: stx1, stx1+stx2, stx1+eae A, stx1+E-hly A, stx1+eae A+E-hly A, eae A and E-hly A. It was found that VTEC comprised 6.4% and 21% of the total E. coli isolates from slaughtered small ruminants and slaughterhouses/ butchers' shops, respectively. The VTEC comprised 76.2% of the virulent isolates. The proportion of stx1:stx1+stx2 patterns was 19:1. It was found that the characterized complex VTEC (containing eae A and/or E-hly A) possessed three virulence patterns, including (VTEC) stx1 +eae A, (VTEC/EHEC) stx1 +E-hly A and (VTEC/EHEC) stx1 +eae A +E-hly A in percentages of 30%, 25% and 10%, respectively, in relation to the total VTEC isolates. Only two VTEC isolates were characterized as E. coli O157 and O26 serotypes, as highly pathogenic strains. Each of the O157 and O26 VTEC isolates was in a percentage of 0.4% in relation to the total E. coli isolates with virulent patterns stx1, eae A and E-hly A. The rest of the VTEC isolates were non-O157 VTEC. The antibiotic sensitivity test showed that the isolated VTEC was highly sensitive to gentamicin and co-trimoxazole and highly resistant to tetracycline and ampicillin.

The aims of this study are to synthesis silver nanoparticles (AgNPs) using the culture supernatant of the fungal strain Tritirachium oryzae W5H and to investigate the antibacterial activity of AgNPs individually and in combination with some antibiotics and essential oil of the plant Centaurea damascena. The colour of the filtrate with silver nitrate solution changed to intense brown after 72 h of incubation. The UV-Vis is spectrum shows a surface plasmon resonance (SPR) peak of AgNPs at 425 nm. For confirmation of the presence of AgNPs in the solution, analysis of transmission electron microscopy (TEM) image, scanning electron microscope (SEM) micrograph and SEM-EDS were recorded. The current study showed that AgNPs possess broad spectrum activity with inhibition zone ranged from 12 nm to 22 mm. Notable synergy was seen between AgNPs and either vancomycin, nitrofurantoin, chloramphenicol or tetracycline, against Pseudomonas aeruginosa, with a 2.4-fold to 9-fold, increase in fold area of inhibition (IFA). Similarly, AgNPs with gentamicin, tetracycline, ampicillin, cefotaxime and trimethoprim against E. coli, P. aeruginosa, S. aureus and S. epidermidis had a synergy of 1-fold to 10-folds. In addition, synergy was observed between AgNPs, essential oil (EO) of C. damascena and either amoxicillin, ampicillin, trimethoprim or nitrofurantoin against S. epidermidis by 0.7-fold to 3.7-fold and with trimethoprim against P. aeruginosa, increased the IFA by 1.3-fold. Gentamicin led to the greater enhancement in the IFA up to 9-folds. Moreover, effective synergy was seen between EO of C. damascena and either gentamicin or amoxicillin against E. coli by 11.3-fold and 3.7-fold, respectively, whereas amoxicillin against P. aeruginosa and S. epidermidis by 11.25-fold and 1.8-fold IFA, respectively. The results of this study may lead to the new concepts of antibacterial agents that could contain nanoparticles (NPs) or containing new substances that are likely to have extensive synergy of antibiotics with NPs and essential oils for medicinal plants.

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Overexpression of c-Myc plays an essential role in leukemogenesis and drug resistance, making c-Myc an attractive target for cancer therapy. However, targeting c-Myc directly is impossible, and c-Myc upstream regulator pathways could be targeted instead. This study investigated the effects of thymoquinone (TQ), a bioactive constituent in Nigella sativa, on the activation of upstream regulators of c-Myc: the JAK/STAT and PI3K/AKT/mTOR pathways in HL60 leukemia cells. Next-generation sequencing (NGS) was performed for gene expression profiling after TQ treatment. The expression of c-Myc and genes involved in JAK/STAT and PI3K/AKT/mTOR were validated by quantitative reverse transcription PCR (RT-qPCR). In addition, Jess assay analysis was performed to determine TQ’s effects on JAK/STAT and PI3K/AKT signaling and c-Myc protein expression. The results showed 114 significant differentially expressed genes after TQ treatment (p < 0.002). DAVID analysis revealed that most of these genes’ effect was on apoptosis and proliferation. There was downregulation of c-Myc, PI3K, AKT, mTOR, JAK2, STAT3, STAT5a, and STAT5b. Protein analysis showed that TQ also inhibited JAK/STAT and PI3K/AKT signaling, resulting in inhibition of c-Myc protein expression. In conclusion, the findings suggest that TQ potentially inhibits proliferation and induces apoptosis in HL60 leukemia cells by downregulation of c-Myc expression through inhibition of the JAK/STAT and PI3K/AKT signaling pathways.

Background and aims: Branched chain amino acids (BCAAs) can be tightly connected to metabolism syndrome (MetS) which can be counted as a metabolic indicator in the case of insulin resistance (IR). The aim of this study was to assess the potential role of these acids under oxidative stress. Material and Methods: the in vitro antioxidant activity of BCAAs was assessed using free radical 1, 1-diphenyl-2-picryl-hydrazyl (DPPH) scavenging assays. For further check, a qRT-PCR technique was madefor detection the extent of alterations in gene expression of antioxidative enzymes (catalase and glutathione peroxidase (Gpx)) in lipopolysaccharides (LPS(-induced macrophages RAW 264.7 cell line. Additionally, BCAAs antioxidant activity was evaluated based on plasma H2O2 levels and xanthine oxidase (XO) activity in prooxidative LPS-treated mice. Results: Different concentrations of BCAAs affected on DPPH radical scavenging activity but to lesser extent than the ascorbic acid. Besides, BCAAs obviously upregulated the gene expression levels of catalases and Gpx in LPS-modulated macrophage RAW 264.7 cell line. In vivo BCAAs significantly minimized the level of plasma H2O2 as well as the activity of XO activity under oxidative stress. Conclusion: our current findings suggest that BCAAs supplementation may potentially serve as a therapeutic target for treatment of oxidative stress occurs with atherosclerosis, IR-diabetes, MetS and tumorigenesis.