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 ß-lactamases, known as extended-spectrum ß-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 ß-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.

Validated HPLC-PDA methodology utilized for simultaneous determination of Etoricoxib and Paracetamol in the presence of Paracetamol toxic impurities.

Etoricoxib (ETO), Paracetamol (PCM), and two toxic impurities for Paracetamol impurity K (4-aminophenol (PAP)) and impurity E (para-hydroxy acetophenone (PHA)) were separated using a simple and selective HPLC method that was tested for the first time. PCM is a commonly used analgesic and antipyretic medication that has recently been incorporated into COVID-19 supportive treatment. Pharmaceuticals containing PCM in combination with other analgesic-antipyretic drugs like ETO help to improve patient compliance. The studied drugs and impurities were separated on a GL Sciences Inertsil ODS-3 (250 × 4.6) mm, 5.0 µm column, and linear gradient elution was performed using 50 mM potassium dihydrogen phosphate adjusted to pH 4.0 with ortho-phosphoric acid and acetonitrile as mobile phase at 2.0 mL/min flow rate at 25 °C and UV detection at 220 nm. The linearity range was 1.5-30.0 µg/mL for ETO and PCM while 0.5-10.0 µg/mL for PAP and PHA, with correlation coefficients (r) for ETO, PCM, PAP, and PHA of 0.9999, 0.9993, 0.9996, and 0.9998, respectively. The proposed method could be used well for routine analysis in quality control laboratory.

Experimentally designed electrochemical sensor for therapeutic drug monitoring of Ondansetron co-administered with chemotherapeutic drugs.

The experimental design extracts valuable information about the main effects and interactions from the least number of experiments. The current work constructs a solid-state sensor for selective assay of Ondansetron (OND) in pharmaceutical dosage form and plasma samples. During optimization, the Design Expert® statistical package constructed a custom design of 15 sensors with different recipes. We fed the software with the experimentally observed performance parameters for each sensor (slope, LOQ, correlation coefficient, and selectivity coefficient for sodium ions). The computer software analyzed the results to construct a prediction model for each response. The desirability function was adjusted to optimize the Nernstian slope, minimize the LOQ and selectivity coefficients, and maximize the correlation coefficient (r). The practical responses of the optimized sensor were close to those predicted by the model (slope = 60.23 mV/decade slope, LOQ = 9.09 × 10-6 M, r = 0.999, sodium selectivity coefficient = 1.09 × 10-3). The sensor successfully recovered OND spiked to tablets and human plasma samples with mean percentage recoveries of 100.01 ± 1.082 and 98.26 ± 2.227, respectively. Results were statistically comparable to those obtained by the reference chromatographic method. The validated potentiometric method can be used for fast and direct therapeutic drug monitoring of OND co-administered with chemotherapeutic drugs in plasma samples.

Highly selective heteroaromatic sulfur containing polyamides for Hg+2 environmental remediation.

Environmental remediation concerns about pollution and contamination removal from environmental media, such as soil, air, or surface water. Enormous efforts have been applied in metal removal from surface water. In this study, four novel heteroaromatic sulfur-containing polyamides 6a-d carry both types of aliphatic and aromatic species in their polymer backbones as selective adsorbents for Hg+2 metal ion from aqueous solution have been synthesized in considerable amounts. The polycondensation method at low temperature is used as a simple and low coast polymerization technique. This occurred by the interaction of the thiophene-based monomer 5 with different diacid chlorides of both types. Beforehand the polymerization, the structures of monomer 5 were confirmed by spectral and elemental analyses. Also, the structures of the new polymers were investigated by both spectral and elemental analysis; besides their solubility, GPC data, XRD diffraction patterns, thermal analysis, and FE-SEM micrographs. The synthesized polymers were freely soluble in polar protic solvents due to the presence of heteroaromatic sulfur functional groups. Furthermore, the analytical competition of the new polymers has been tested using inductively coupled plasma-optical emission spectrometry (ICP-OES) for its selective extraction across different metal ions. Polymer 6c was the most selective toward Hg+2 and considered as a highly selective adsorbent for Hg+2 environmental remediation among all derivatives and its adsorption detection and efficiency were also investigated. Polymer 6c showed the most effective adsorption quantity on its surface at pH = 1. Moreover, the calculated adsorption isotherm showed a typical isotherm to the Langmuir adsorption type. This showed that the adsorption capacity of polymer 6c for Hg+2 was 47.95 mg g-1. These novel polymers are serving as simple and inexpensive heavy metal ions adsorbent materials from drinking water and wastewater.

Design, synthesis and cytotoxic activity of water-soluble quinones with dibromo-p-benzoquinone cores and amino oligo(ethylene glycol) side chains against MCF-7 breast cancer cells.

A series of novel quinones was synthesized by reacting tetrabromo-p-benzoquinone with amino oligo(ethylene glycol) dendrons of generation numbers g = 0-2. According to the performed shake-flask experiments, their aqueous solubility (S = 18 mg l-1-1.6 g ml-1) and partition coefficients (log Poct/wat = 2.53-0.21) can be tuned in a wide range as a function of g. In vitro cytotoxicity assays of tetrabromo-p-benzoquinone and its derivatives against MCF-7 human breast cancer cells showed a concentration- and generation-specific biological activity with IC50-values as low as 0.8 µM. Further investigations revealed a considerable selectivity against cancer cells, as indicated by a weak cytotoxicity against human skin fibroblast cells (>80% survival) within the studied range of concentrations. The results demonstrate that these novel amino oligo(ethylene glycol) dendrons depict versatile tools to ameliorate physical and pharmacological characteristics of extremely hydrophobic molecules and make them susceptible to biological applications.

Thermoresponsive dendrimers based on oligoethylene glycols: design, synthesis and cytotoxic activity against MCF-7 breast cancer cells.

Three interesting thermoresponsive branched oligoethylene glycol dendrimers based on tetrabromohydroquinone were efficiently synthesized from tetrabromohydroquinone and three different oligoethylene glycol derivatives. By visual inspection, all these dendrimers are water-soluble at room temperature. The thermoresponsive behaviors were investigated by using UV/vis turbidity measurement at different temperatures for 0.25 wt% of aqueous solutions from D1, D2 and D3. The cytotoxicity of the prepared dendrimers was tested against MCF-7 breast cancer cells. All tested dendrimers showed considerable results, where D2 dendrimer gave the best result; it showed cytotoxicity against MCF-7 cell line with IC50 of 1.07 µg/mL and resistant fraction equals 1.97%, the other two dendrimers showed a modest cytotoxic profile.