Madeha Ghobashy

The purpose of this study was to investigate the prevalence, antibiotic resistance and certain virulence genes of the most predominant bacterial pathogens causing BRD. A total of 225 calves; 55 apparently healthy and 170 diseased; were sampled. Bacteriological examination, antimicrobial susceptibility testing and PCR based detection of some virulence genes were performed. In addition, the serotyping of E. coli was performed using the slide agglutination test. The most predominant bacterial pathogens retrieved from apparently healthy calves were E. coli (16.4%) and S. aureus (10.9%), and in pneumonic calves were E. coli (23.5%), P. vulgaris (12.4%) and S. aureus (11.8%). The most prevalent virulence gene in E. coli was the fimH gene (100%), followed by eaeA gene (24.5%) and hly gene (20.4%). All the examined S. aureus strains harbored spa and coa genes; likewise, all P. multocida strains harbored toxA gene. The majority of the isolated strains displayed remarkable sensitivity to norf...

Calf diarrhea is one of the considerable infectious diseases in calves, which results in tremendous economic losses globally. To determine the prevalence of Shiga-toxigenic E. coli (STEC) and Enterotoxigenic E. coli (ETEC) incriminated in calf diarrhea, with special reference to Shiga- toxins genes (stx1 and stx2) and enterotoxins genes (lt and sta) that govern their pathogenesis, as well as the virulence genes; eaeA (intimin) and f41(fimbrial adhesion), and the screening of their antibiogram and antimicrobial resistance genes; aadB, sul1, and bla-TEM, a total of 274 fecal samples were collected (April 2018–Feb 2019) from diarrheic calves at different farms in El-Sharqia Governorate, Egypt. The bacteriological examination revealed that the prevalence of E. coli in diarrheic calves was 28.8%. The serotyping of the isolated E. coli revealed 7 serogroups; O26, O128, O111, O125, O45, O119 and O91. Furthermore, the Congo red binding test was carried out, where 89.8% of the examined strai...

Traditional treatment of infectious diseases is based on compounds that kill or inhibit growth of bacteria. A major concern with this approach is the frequent development of bacterial strains resistant to antibiotics. The discovery of communication systems (quorum sensing systems) regulating bacterial virulence afforded a novel opportunity to control infectious bacteria without interfering with growth. This study introduces not only a new mode of action and possible validation for traditional plant use, but also a potentially new therapeutic direction for the treatment of bacterial infections via inhibiting the bacterial virulence factors.

Klebsiella pneumoniae is a member of the pathogenic group which causes a variety of human disease and outbreak problem in Hospitals. These organisms challenged the treatment by multidrug resistance. Furthermore, to develop new strategies and prevent bacterial pathogen outbreak must be studying virulence mechanisms, virulence factors and role of these factors in pathogenicity. Fifty K. pneumoniae isolates were recovered from different collected clinical specimens from Ain Sham Specialized (Ksp) and Al-Damardash Hospitals (KD) Cairo, Egypt, also from Sabha medical center Hospital (Ksa) Sabha, Libya. Isolates were identified by phenotypic and physiological m e t h o d s b y u s i n g A P I 2 0 E s y s t e m. I n general, the K. pneumoniae (KD & Ksp) isolates displayed higher adherence rate to Vero cells and cytotoxicity too. These results were exhibited significantly (P>0.05). Twenty percent were at higher adherence range (>8%) and 16% of cytotoxicity at very high level (<75%)...

Selenium (Se) as a bioactive micronutrient could be augmented via transforming into nanoparticles (NPs), especially using biogenic protocols, for usage as an antimicrobial element. The reducing power of costus (Saussurea costus) root extract (SCE) was employed for phytosynthesis of Se-NPs through a simple and rapid protocol that included stirred mixing of 10 mM Na2SeO3 with 1.0% SCE solution for 4 h. The phytosynthesized SCE/Se-NP composite was obtained with a mean diameter of 6.13 nm and a zeta potential of −42.8 mV. Infrared analyses revealed the involvement of many SCE phytogroups in Se-NP synthesis, whereas transmission microscopy displayed well distribution and spherical shapes of the phytosynthesized NPs. The antibacterial assessments against foodborne pathogens (Escherichia coli, Salmonella typhimurium and Staphylococcus aureus) revealed the superior powers of SCE/Se-NPs and the elevated potentialities of SCE and Se-NPs for inhibition of bacterial pathogens. The scanning micr...

Antitumor and antimicrobial resistance are a habitual global issue, which continually demands finding new natural compounds to encounter the resistance. Pulicaria undulata (Forssk.) Oliver. (Asteraceae family) has numerous promising medicinal properties. The recent work aimed at determination of antitumor effects of three extracts of P. undulata on three types of human carcinoma; HEPG-2 hepatocellular carcinoma, MCF-7 breast carcinoma and HCT-116 colon carcinoma cell lines. Anticancer activity was assessed through studying the viability of the cancer cells and apoptotic pathway. Also, antimicrobial potency of different extracts was assessed against studied human pathogens (five Gram negative bacteria, two Gram positive bacteria and yeast). The results reveal that chloroform extract has different levels of cytotoxicity toward the three types of cancer cell lines. A considerable decline in cancer cell rates has been linked to increasing in concentration of plant extract. The half maxi...

Various virulence factors including invasion, adhesion, cytotoxicity, protease, lipase, elastase, urease production and swarming migration were determined for 24 Proteus isolates recovered from clinical specimens. The results showed that the distribution of virulence factors was different among the test isolates and strain specific in most cases. All Proteus isolates showed invasion and adhesion capabilities with different extents. In addition, they

New air stable low spin Ru(III) complexes have been synthesized, from the reaction of 2-(2-(4-X-phenylhydrazono)-2-(1H-benzo[1,2,3]triazol-1-yl)-1-phenylethanone, X=H, F, Cl, Br, NO2, OCH3 and CH3 with RuCl3.3H2O in ethanol in presence of KOH in the media. The resulted complexes are studied by elemental analysis, molar conductivity, thermal analysis magnetic and spectral (UV-Vis., FTIR, EPR) studies. The redox behavior of the complexes is investigated by cyclic voltammetry method. The magnetic and spectral studies showed that binuclear structure of the complexes in the general form of [[Ru 2 (L 1-7) 4 Cl 2 ]. nH 2 O. Some antibacterial activities of the ligands and their complexes have also been studied