ABSTRACT
BACKGROUND: The emergence of carbapenem-resistant and extensively drug-resistant (XDR) Acinetobacter baumannii as well as inadequate effective antibiotics calls for an urgent effort to find new antibacterial agents. The therapeutic efficacy of two human scFvs, EB211 and EB279, showing growth inhibitory activity against A. baumannii in vitro, was investigated in immunocompromised mice with A. baumannii pneumonia. RESULTS: The data revealed that infected mice treated with EB211, EB279, and a combination of the two scFvs showed better survival, reduced bacterial load in the lungs, and no marked pathological abnormalities in the kidneys, liver, and lungs when compared to the control groups receiving normal saline or an irrelevant scFv. CONCLUSIONS: The results from this study suggest that the scFvs with direct growth inhibitory activity could offer promising results in the treatment of pneumonia caused by XDR A. baumannii.
Subject(s)
Acinetobacter Infections , Acinetobacter baumannii , Pneumonia , Single-Chain Antibodies , Humans , Animals , Mice , Single-Chain Antibodies/pharmacology , Single-Chain Antibodies/therapeutic use , Acinetobacter Infections/drug therapy , Acinetobacter Infections/microbiology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Pneumonia/drug therapy , Pneumonia/microbiology , Drug Resistance, Multiple, Bacterial , Microbial Sensitivity TestsABSTRACT
Medicinal plants such as Leutea avicennae Mozaff. (Apiaceae) have been shown some biological potential for preventing and treating diseases. Fractions and isolated compounds were tested on colon carcinoma (HT-29), cervical carcinoma (HeLa), breast carcinoma (MCF-7), and mouse embryonic fibroblast (NIH/3T3) cell lines. The BSLT method was used for the assessment of the general toxicity of the petroleum ether (PET), chloroform (CHCl3), ethyl acetate (EtOAc), and methanol (MeOH) fractions obtained from the aerial parts of L. avicennae. 1H-NMR and 13 C-NMR spectroscopy were used for structure elucidation. Five compounds, including two coumarins, osthole and umbelliferone, a diterpene phytol, ß-sitosterol, and lauric acid, were isolated for the first time from L. avicennae. Osthole showed potent cytotoxic activity against MCF-7 and HT-29 cell lines with IC50 values of 4.23 ± 0.26 and 12.11 ± 0.13 µg/mL, respectively. Phytol demonstrated potent cytotoxic activity towards MCF-7 and HeLa cell lines with IC50 values of 6.80 ± 0.08 and 12.27 ± 0.18 µg/mL, respectively.