Extended-spectrum β-lactamases (ESβLs) pose a serious problem in the treatment of urinary tract infections (UTIs). The ESβL-producing organism is an expanding global health problem. Therefore, screening for ESβL, detection of their drug-resistance pattern, and molecular characterization should be a continuous process. The present study was performed to determine the antibiotic resistance profile and the genetic characterization of ESβL isolates from hospital-and community-acquired UTIs. Two hundred fifty Enterobacteriaceae isolates were obtained from urine samples of outpatient clinic attendants and hospitalized patients at Kasr Al-Aini Hospital. By phenotypic screening tests, 100 ESβL isolates were detected among the studied groups. Furthermore, detection of beta-lactamase (bla) cefotaxime (CTX)-M, sulfhydryl variable, and temoneira ESβL genes was investigated by polymerase chain reaction. A subset of 25 CTX-M-positive isolates was further identified by gene sequencing technology. Among the 100 ESβL isolates, 66% were Escherichia coli and 34% were Klebsiella spp. There was no statistical difference in the prevalence of ESβL Enterobacteriaceae in community-acquired versus hospital-acquired UTIs. The susceptibility of all ESβL isolates to carbapenems was the most prevalent finding. In addition, all ESβL E. coli isolates were susceptible to fosfomycin, whereas all community-acquired ESβL isolates were susceptible to nitrofurantoin. A total of 98% of the ESβL isolates harbored bla-CTX-M genes, with CTX-M-15 being the most prevalent. It could be concluded that ESβL production is present at a high rate among Egyptian patients with hospital-and community-acquired UTI. The high prevalence of bla-CTX-M may suggest it as a candidate for molecular screening of ESβL.

Dementia is an ominous neurological disease. Scientists proposed a link between its occurrence and the presence of Toxoplasma gondii (T. gondii). The long-term sequels of anti-Toxoplasma premunition, chiefly dominated by TNF-α, on the neurons and their receptors as the insulin-like growth factor-1 receptor (IGF-1R), which is tangled in cognition and synaptic plasticity, are still not clear. IGF-1R mediates its action via IGF-1, and its depletion is incorporated in the pathogenesis of dementia. The activated TNF-α signaling pathway induces NF-κβ that may induce or inhibit neurogenesis. This study speculates the potential impact of anti-Toxoplasma immune response on the expression of IGF-1R in chronic cerebral toxoplasmosis. The distributive pattern of T. gondii cysts was studied in association with TNF-α serum levels, the in situ expression of NF-κβ, and IGF-1R in mice using the low virulent ME-49 T. gondii strain. There was an elevation of the TNF-α serum level (p value ≤ 0.004) and significant upsurge in NF-κβ whereas IGF-1R was of low abundance (p value < 0.05) compared to the controls. TNF-α had a strong positive correlation with the intracerebral expression of NF-κβ (r value ≈ 0.943, p value ≈ 0.005) and a strong negative correlation to IGF-1R (r value -0.584 and -0.725 for area% and O.D., respectively). This activated TNF-α/NF-κβ keeps T. gondii under control at the expense of IGF-1R expression, depriving neurons of the effect of IGF-1, the receptor’s ligand. We therefore deduce that T. gondii immunopathological reaction may be a road paver for developing dementia.

Methicillin resistance in Staphylococcus aureus has become prevalent globally. Moreover, biofilm-formation makes it more difficult to eradicate bacteria by antibiotics. The mazEF toxin-antitoxin system encodes for mazF, which acts as an endoribonuclease that cleaves cellular mRNAs at specific sequence motifs (ACA), and mazE, which opposes the mazF action. Our goal was to detect mazEF expression in methicillin-resistant S. aureus (MRSA) isolates compared with methicillin-sensitive S. aureus (MSSA) isolates and determine its relation to methicillin susceptibility as well as biofilm-formation. According to their susceptibility to cefoxitin disks, 100 S. aureus isolates obtained from patients admitted to Cairo University Hospitals were categorized into 50 MSSA and 50 MRSA according to their susceptibility to cefoxitin disks (30 µg). Antimicrobial susceptibility and biofilm-formation were investigated using the disk diffusion method and tissue culture plate method, respectively. Finally, using real-time PCR, mazEF expression was estimated and correlated to methicillin susceptibility and biofilm formation. Both MRSA and MSSA isolates showed the best sensitivity results with linezolid and gentamicin, where about 88% of MRSA isolates and 96% of MSSA isolates were sensitive to linezolid while 76% of MRSA isolates and 84% of MSSA isolates were sensitive to gentamicin. MRSA isolates were significantly more able to form biofilm than MSSA isolates (p-value = 0.037). The mazEF expression was significantly correlated to methicillin resistance in S. aureus (p-value < 0.001), but not to biofilm-formation.

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To determine the safety and efficacy of black tea extract in the treatment of bacterial conjunctivitis in a rabbit model and compare it with that of gatifloxacin drops. Methods: Black tea extract was tested in vitro on bacterial cultures of methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. Forty-two rabbit eyes were cultured with either MRSA (n¼21) or P. aeruginosa (n¼21) and further divided into a control group (n¼5), a tea group (n¼8) treated with black tea extract, and a gatifloxacin group (n¼8) treated with 0.3% gatifloxacin eye drops. Conjunctival swabs were collected on the third and fifth days. Results: The tea extract successfully inhibited the growth of both organisms at a concentration of 400 mg/mL. Rabbits in the treatment groups showed a reduction in the clinical index on day 2 (P,0.01), unlike the control group (P¼0.1), for both organisms. Resolution of conjunctivitis was achieved on days 4 and 5 in the tea and gatifloxacin groups, respectively. On days 3 and 5, while the control group still showed considerable bacterial growth, the tea and gatifloxacin groups showed its inhibition. Conclusion: Tea extract has antimicrobial effects similar to those of gatifloxacin in a rabbit model of conjunctivitis.