The interactions between a virus and its host vary in space and time and are affected by the presence of molecules that alter the physiology of either the host or the virus. Determining the molecular mechanisms at the basis of these interactions is paramount for predicting the fate of bacterial and phage populations and for designing rational phage-antibiotic therapies. We study the interactions between stationary phase Burkholderia thailandensis and the phage ΦBp-AMP1.
View Article and Find Full Text PDFMelioidosis is a disease that is difficult to treat due to the causative organism, being inherently antibiotic resistant and it having the ability to invade, survive, and replicate in an intracellular environment. Combination therapy approaches are routinely being evaluated in animal models with the aim of improving the level of protection and clearance of colonizing bacteria detected. In this study, a subunit vaccine layered with the antibiotic finafloxacin was evaluated against an inhalational infection with in Balb/c mice.
View Article and Find Full Text PDFThis study determined the activity of finafloxacin against panels of bacterial strains, representative of those associated with infection in cystic fibrosis patients and predominately isolated from clinical cases of respiratory disease. Many of these isolates were resistant to various antimicrobials evaluated including the aminoglycosides, cephalosporins, carbapenems and fluoroquinolones. Broth microdilution assays were performed at neutral and acidic pH, to determine antimicrobial activity.
View Article and Find Full Text PDFAntimicrobial resistance is a global issue, and the investigation of alternative therapies that are not traditional antibiotics are warranted. Novel bacterial type II topoisomerase inhibitors (NBTIs) have recently emerged as a novel class of antibiotics with reduced potential for cross-resistance to fluoroquinolones due to their novel mechanism of action. This study investigated the activity of a series of cyclohexyl-oxazolidinone bacterial topoisomerase inhibitors against type strains of and .
View Article and Find Full Text PDF, the causative agent of the disease melioidosis, has been isolated from the environment in 45 countries. The treatment of melioidosis is complex, requiring lengthy antibiotic regimens, which can result in the relapse of the disease following treatment cessation. It is important that novel therapies to treat infections with be assessed in appropriate animal models, and discussions regarding the different protocols used between laboratories are critical.
View Article and Find Full Text PDF, the causative agent of glanders, is principally a disease of equines, although it can also infect humans and is categorized by the U.S. Centers for Disease Control and Prevention as a category B biological agent.
View Article and Find Full Text PDFis the causative agent of melioidosis, a multifaceted disease. A proportion of the mortality and morbidity reported as a result of infection with this organism may be due to the premature cessation of antibiotic therapy typically lasting for several months. The progression of re-emergent disease was characterised in Balb/c mice following cessation of a 14 day treatment course of co-trimoxazole or finafloxacin, delivered at a human equivalent dose.
View Article and Find Full Text PDFThe efficacy of finafloxacin as a component of a layered defense treatment regimen was determined and against an infection with . Doxycycline was down-selected from a panel of antibiotics evaluated and used in combination with finafloxacin in a Balb/c mouse model of inhalational melioidosis. When treatment was initiated at 24 h post-infection with , there were no differences in the level of protection offered by finafloxacin or doxycycline (as monotherapies) when compared to the combination therapy.
View Article and Find Full Text PDFFinafloxacin is a novel fluoroquinolone with optimal antibacterial activity in low pH environments, therefore offering a therapeutic advantage over some traditional antibiotics, in treating bacterial infections associated with acidic foci. , the causative agent of Q fever, is a bacterium which resides and replicates in acidic intracellular parasitic vacuoles. The efficacy of finafloxacin was evaluated using the A/J mouse model of inhalational Q fever and was compared to doxycycline, the standard treatment for this infection and ciprofloxacin, a comparator fluoroquinolone.
View Article and Find Full Text PDFInfection with aerosolized or can lead to lethal disease in humans if treatment is not initiated promptly. Finafloxacin is a novel fluoroquinolone which has demonstrated broad-spectrum activity against a range of bacterial species , and in humans, activity which is superior in acidic, infection-relevant conditions. Human-equivalent doses of finafloxacin or ciprofloxacin were delivered at 24 h (representing prophylaxis) or at 72 or 38 h (representing treatment) postchallenge with or , respectively, in BALB/c mouse models.
View Article and Find Full Text PDFAntimicrob Agents Chemother
September 2019
This study investigated the activity of finafloxacin against panels of the biodefence pathogens. Broth microdilution assays were performed at neutral and acidic pH, to determine the effectiveness of the antibiotics in conditions typical of an intracellular environment. In all instances, finafloxacin demonstrated superior activity at low pH.
View Article and Find Full Text PDFBurkholderia pseudomallei is the causative agent of the tropical disease melioidosis. Its genome encodes an arsenal of virulence factors that allow it, when required, to switch from a soil dwelling bacterium to a deadly intracellular pathogen. With a high intrinsic resistance to antibiotics and the ability to overcome challenges from the host immune system, there is an increasing requirement for new antibiotics and a greater understanding into the molecular mechanisms of B.
View Article and Find Full Text PDFThe efficacy of the novel fluoroquinolone finafloxacin was evaluated as a potential therapeutic and , following an intranasal infection of strain SchuS4 in BALB/c mice. We demonstrated that short treatment courses of finafloxacin provide high levels of protection, with a single dose resulting in a significant increase in time to death when compared to ciprofloxacin. In addition, following investigation into the window of opportunity for treatment, we have shown that finafloxacin can provided protection when administered up to 96 h post-challenge.
View Article and Find Full Text PDFDisulfiram (DSF) can help treat alcohol dependency by inhibiting aldehyde dehydrogenase (ALDH). Genomic analysis revealed that Francisella tularensis, the causative agent of tularemia, has lost all but one ALDH-like domain and that this domain retains the target of DSF. In this study, minimum inhibitory concentration (MIC) assays demonstrated that both DSF and its primary metabolite diethyldithiocarbamate (DDC) have strong antimicrobial activity against F.
View Article and Find Full Text PDFis the causative agent of melioidosis, a serious disease endemic in Southeast Asia and Northern Australia. Antibiotic treatment is lengthy and relapse often occurs. Finafloxacin is a novel fluoroquinolone with increased antibacterial activity in acidic conditions in contrast to other fluoroquinolones which demonstrate reduced activity at a lower pH.
View Article and Find Full Text PDFInhalation of can lead to pneumonic plague, which without treatment is inevitably fatal. Two novel formulations of liposome-encapsulated ciprofloxacin, 'ciprofloxacin for inhalation' (CFI, Lipoquin) and 'dual release ciprofloxacin for inhalation' (DRCFI, Pulmaquin) containing CFI and ciprofloxacin solution, are in development. These were evaluated as potential therapies for infection with .
View Article and Find Full Text PDFLiposome-encapsulated ciprofloxacin for inhalation (CFI) was investigated as a putative postexposure therapeutic for two strains of Francisella tularensis. The efficacies of oral ciprofloxacin and intranasally instilled CFI could not be distinguished in a mouse model of infection with the F. tularensis live vaccine strain (LVS), where a single dose of either formulation offered full protection against a lethal challenge.
View Article and Find Full Text PDFBurkholderia pseudomallei is the causative agent of the disease melioidosis, which is prevalent in tropical countries and is intractable to a number of antibiotics. In this study, the antibiotic co-trimoxazole (trimethoprim/sulfamethoxazole) was assessed for the post-exposure prophylaxis of experimental infection in mice with B. pseudomallei and its close phylogenetic relative Burkholderia mallei, the causative agent of glanders.
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