PREVALENCE AND MOLECULAR CHARACTERIZATION OF EXTENDED SPECTRUM β-LACTAMASES IN KLEBSIELLA PNEUMONIAE ISOLATES FROM CANCER PATIENTS AND OTHERS

Objective: Klebsiella pneumoniae is highly prevalent in hospitals and causes many nosocomial infections. The study sought to determine prevalence rates of extended spectrum β-lactamases (ESBLs) in clinical isolates of K. pneumoniae from Cairo, Egypt and to detect the ESBL-encoding genes in the isolates.Methods: K. pneumoniae isolates were collected through two-year period (2011-2012). Identification of K. pneumoniae was carried out using automated Microscan and standard biochemical tests. ESBL pattern and minimum inhibitory concentrations (MICs) were detected using Clinical and Laboratory Standards Institute guidelines and confirmatory tests. Multiplex polymerase chain reaction for ESBL-encoding genes and plasmid profiling were performed.Results: In the present work; 112 isolates, 75 of them from cancer patients, were characterized. High proportion (52 of 112, 46 %â€) of ESBLs among the isolates were detected. Highest prevalence of ESBLs was seen among cancer patients, 39 isolates of 75 (52%). Plasmid profile for ESBL-producing K. pneumoniae isolates showed different sizes and numbers of plasmids in all isolates. MICs for all ESBL-producing isolates revealed high resistance rates with tetracycline (100%), cefepime (96%), gentamycin (90%) and ciprofloxacin (79%). Whereas, only two isolates (4%) were resistant to both carbapenem drugs tested, imipenem and meropenem. blaTEM, blaSHV, and bla CTX-M were performed for all ESBL-producing isolates. Five patterns of ESBL-encoding genes were detected. The most prevalent ESBL-encoding gene was blaTEM;alone in 40% and with other ESBL-encoding gene(s) in 48% of the isolates.Conclusion: High prevalence of ESBL (46%) in our isolates suggesting the need for continuous monitoring of emergence of this pattern in our region.Â

Antimicrobial susceptibility profile of Pseudomonas aeruginosa isolates in Egypt

Purpose: Pseudomonas aeruginosa is a leading cause of nosocomial respiratory tract, urinary tract and skin infections. Data are sparse on the antimicrobial resistance of P. aeruginosa in Egypt. We sought to detect and compare the antimicrobial susceptibility of P. aeruginosa isolates from respiratory tract, urinary tract and skin infections at 3 Egyptian hospitals. Materials and Methods: Minimum inhibitory concentrations of antibiotics were determined by the agar dilution method. Results: P. aeruginosa respiratory tract infections isolates were 100% resistant to ampicillin, ampicillin/sulbactam, amoxicillin, amoxicillin/clavulanate and chloramphenicol, highly resistant to cefuroxime (89%), tetracycline (89%) and azithromycin (84%), and susceptible to norfloxacin (89%), amikacin (84%) and meropenem (68%). P. aeruginosa urinary tract infection isolates were 100% resistant to ampicillin, amoxicillin, chloramphenicol, cefuroxime and tetracycline, highly resistant to amoxicillin/clavulanate (95%), azithromycin (95%), cefalexin (91%) and ampicillin/sulbactam (82%), and susceptible to amikacin (82%), meropenem (73%) and norfloxacin (64%). P. aeruginosa skin infection isolates were 100% resistant to ampicillin and amoxicillin, highly resistant to tetracycline (95%), amoxicillin/clavulanate (95%), cefalexin (87%) and azithromycin (84%), and susceptible to amikacin (87%), norfloxacin (71%) and meropenem (68%). The anti-pseudomonal effect of antibiotics varied among different infection sites only for ampicillin/sulbactam, cefoperazone or chloramphenicol but not with the other tested antibiotics. Conclusions: Norfloxacin and amikacin could be used for initial therapy for P. aeruginosa mediated respiratory tract infections. Amikacin, meropenem and norfloxacin could be used for P. aeruginosa mediated urinary tract and skin infections. Such studies are essential to determine the current guidelines for empirical therapy regimens, which vary by location, and help with the establishment of effective infection control measures

Characterization of Pseudomonas aeruginosa isolated from clinical and environmental samples in Minia, Egypt: prevalence, antibiogram and resistance mechanisms

Objectives: To assess the prevalence, levels of antimicrobial susceptibility and resistance mechanisms of Pseudomonas. Methods: A total of 445 clinical isolates and 200 environmental isolates were collected from three hospitals in Minia, Egypt. The MICs of different antibiotics were determined using the agar dilution method. The isolates were tested for beta-lactamase production and for the presence of efflux pumps. Results: Out of the 445 clinical specimens, 107 Pseudomonas strains (24%) and 81 Pseudomonas aeruginosa strains were isolated (18.2%). Out of the 200 environmental specimens, 57 Pseudomonas strains (28.5%) and 39 P. aeruginosa strains were isolated (19.5%). Amikacin was the most active drug against P. aeruginosa followed by meropenem, cefepime and fluoroquinolones. P. aeruginosa was highly resistant to all other antibiotics tested. The environmental isolates of P. aeruginosa exhibited higher antibiotic resistance than clinical isolates. Mechanisms of resistance used by P. aeruginosa included beta-lactamase production and multiple drug resistance efflux pumps. Our results showed that 29 (36%) of the clinical P. aeruginosa isolates and 37 (95%) of the environmental P. aeruginosa isolates were beta-lactamase producers. In addition, P. aeruginosa isolates effectively used an efflux-mediated mechanism of resistance against ciprofloxacin and meropenem, but not gentamicin or cefotaxime. Conclusions: This study examined the prevalence of P. aeruginosa, and its susceptibility patterns to different antibiotics. The presence of antibiotic-resistant P. aeruginosa isolates could be attributed to beta-lactamase production and the use of multiple drug resistance efflux pumps

Additional file 1 of Nitrogen and sulfur-doped carbon quantum dots as fluorescent nanoprobes for spectrofluorimetric determination of olanzapine and diazepam in biological fluids and dosage forms: application to content uniformity testing

Additional file 1. Additional figures and tables

3‑Acetyl-11-keto-β-boswellic Acid-Based Hybrids Alleviate Acetaminophen-Induced Hepatotoxicity in HepG2 by the Regulation of Inflammatory and Oxidative Stress Pathways: An Integrated Approach

In an effort to develop new compounds for managing drug-induced liver injury, we prepared 23 novel hybrids based on 3-acetyl-11-keto-β-boswellic acid (AKBA) using various biocompatible linkers. A bioguided approach was employed to identify the most promising hybrid. Eight compounds exhibited superior anti-inflammatory activity compared to the parent compound. Two of these hybrids (5b and 18) were able to reduce gene expression of TNF-α in LPS-induced inflammation in RAW 264.7 cells, similar to dexamethasone. Subsequently, the hepatoprotective potential of these hybrids was evaluated against acetaminophen (APAP) toxicity in HepG2 cells at doses of 1 and 10 μM. Both hybrids effectively restored cytokine levels, which had been elevated by APAP, to normal levels. Furthermore, they normalized depleted superoxide dismutase and reduced glutathione levels while significantly reducing malondialdehyde (MDA) levels. Network pharmacology analysis suggested that AKBA-based hybrids exert their action by regulating PI3K and EGFR pathways, activating anti-inflammatory mechanisms, and initiating tissue repair and regeneration. Molecular docking studies provided insights into the interaction of the hybrids with PI3K. Additionally, the hybrids demonstrated good stability at different pH levels, following first-order kinetics, with relatively long half-lives, suggesting potential for absorption into circulation without significant degradation

Analytical quality-by-design approach for development and validation of HPLC method for the simultaneous estimation of omarigliptin, metformin, and ezetimibe: application to human plasma and dosage forms

Abstract A simple, selective, and sensitive RP-HPLC method was proposed for the simultaneous determination of two co-administered antidiabetic drugs (omarigliptin and metformin) with an anti-hyperlipidemic drug (ezetimibe) in a medicinally-recommended ratio of 2.5:50:1, respectively. The proposed procedure was optimized by adopting a quality-by-design approach. The influence of different factors on chromatographic responses was optimized by applying the two-level full factorial design (25). The optimum chromatographic separation was achieved using Hypersil BDS C18 column at 45 °C, and the mobile phase pumped isocratically composed of methanol: potassium dihydrogen phosphate buffer (6.6 mM; pH 7, 67:33% v/v) at a flow rate of 0.814 mL/min using 235 nm as a detection wavelength. The developed method was capable of separating this novel mixture in less than 8 min. The calibration plots of omarigliptin, metformin, and ezetimibe showed acceptable linearity over the ranges of 0.2-2.0, 0.5–25.0, and 0.1-2.0 µg/mL with quantitation limits of 0.06, 0.50, and 0.06 µg/mL, respectively. The proposed method was successfully applied to determine the studied drugs in their commercial tablets with high % recoveries (96.8-102.92%) and low % RSD values (less than 2%). The applicability of the method was extended to the in-vitro assay of the drugs in spiked human plasma samples with high % recoveries (94.3-105.7%). The suggested method was validated in accordance with ICH guidelines

Identification of sulphonamide-tethered N-((triazol-4-yl)methyl)isatin derivatives as inhibitors of SARS-CoV-2 main protease

AbstractSARS-CoV-2 pandemic in the end of 2019 led to profound consequences on global health and economy. Till producing successful vaccination strategies, the healthcare sectors suffered from the lack of effective therapeutic agents that could control the spread of infection. Thus, academia and the pharmaceutical sector prioritise SARS-CoV-2 antiviral drug discovery. Here, we exploited previous reports highlighting the anti-SARS-CoV-2 activities of isatin-based molecules to develop novel triazolo-isatins for inhibiting main protease (Mpro) of the virus, a crucial enzyme for its replication in the host cells. Particularly, sulphonamide 6b showed promising inhibitory activity with an IC50= 0.249 µM. Additionally, 6b inhibited viral cell proliferation with an IC50 of 4.33 µg/ml, and was non-toxic to VERO-E6 cells (CC50 = 564.74 µg/ml) displaying a selectivity index of 130.4. In silico analysis of 6b disclosed its ability to interact with key residues in the enzyme active site, supporting the obtained in vitro findings