Journal: Antibiotics

Article Title: A New Promising Anti-Infective Agent Inhibits Biofilm Growth by Targeting Simultaneously a Conserved RNA Function That Controls Multiple Genes

doi: 10.3390/antibiotics10010041

Figure Lengend Snippet: Assessment of PKZ18-22 effect on Staphylococcus biofilms. ( A ) S. aureus biofilm colony forming units (CFU/log 10 ) after 24 h of a single dose antibiotic and the PKZ18 analog PKZ18-22. ( B ) Log reduction after a single dose 24 h challenge. PKZ18-22 treatment exhibited 2.5 log reduction, which corresponds to >99% bacterial cell reduction; significantly greater reduction compared to vancomycin. ( C) Growth of S. aureus after 24 h exposure to PKZ18-22 vs. dosages of vancomycin in the minimum biofilm eradication (MBEC) biofilm model. Optical density measured as a surrogate for turbidity/bacterial growth demonstrated significant growth reduction with PKZ18-22 treatment compared to all vancomycin concentrations and negative controls. ( D ) The MBEC efficacy of a range of concentrations of PKZ18-22 compared with vancomycin using the same parameters as C. (inoculum, media concentration, etc.) but using new lot of PKZ18-22 and vancomycin stocks. No growth with vancomycin. ( E ) The minimum bactericidal concentration (MBC) efficacy of a range of concentrations of PKZ18-22. Scanning electron micrographs of peg surfaces: ( F ) no treatment and ( G ) treatment with PKZ18-22.

Article Snippet: Three independent experiments were conducted and required a checkerboard dilution to test various concentrations of the following combinations (PKZ18 analog + each antibiotic) against S. aureus utilizing an established MBECTM-HTP biofilm model (Innovotech) [ , , ].

Techniques: Concentration Assay

Journal: Antibiotics

Article Title: A New Promising Anti-Infective Agent Inhibits Biofilm Growth by Targeting Simultaneously a Conserved RNA Function That Controls Multiple Genes

doi: 10.3390/antibiotics10010041

Figure Lengend Snippet: PKZ18-22–antibiotic synergy on S. aureus biofilm growth. ( A ) Biofilm grown for 24 h with no treatment. ( B ) Biofilm growth after 24 h exposure to 25 µg/mL PKZ18-22. ( C ) Growth after 24 h exposure to 4 µg/mL gentamicin. ( D ) Growth after 24 h exposure to 64 µg/mL gentamicin + 25 µg/mL PKZ18-22. ( E ) Growth after 24 h exposure to 4 µg/mL vancomycin. ( F ) Growth of S. aureus after 24 h exposure to 4 µg/mL vancomycin + 25 µg/mL PKZ18-22. ( G ) Synergy score matrix for drug combination of PKZ18-22 and gentamicin using a drug interaction Bliss reference model. The highest drug synergy was observed with PKZ18-22 of 25 µg/mL and gentamicin concentrations of 16–64 µg/mL ( p < 0.001). ( H ) Synergy score matrix for drug combination of PKZ18-22 and vancomycin. By definition all synergy scores above zero are synergistic. Synergy scores of PKZ18-22 and vancomycin exhibited significantly lower effects compared to PKZ18-22 and gentamicin. The highest synergy score was observed at 4 µg/mL vancomycin + 25 µg/mL PKZ18-22. Asterisk’s indicate level of confidence in results, probability of obtaining test results: * indicates p < 0.05; ** indicates p < 0.001; *** indicates p < 0.0001.

Article Snippet: Three independent experiments were conducted and required a checkerboard dilution to test various concentrations of the following combinations (PKZ18 analog + each antibiotic) against S. aureus utilizing an established MBECTM-HTP biofilm model (Innovotech) [ , , ].

Techniques:

Journal: Antibiotics

Article Title: A New Promising Anti-Infective Agent Inhibits Biofilm Growth by Targeting Simultaneously a Conserved RNA Function That Controls Multiple Genes

doi: 10.3390/antibiotics10010041

Figure Lengend Snippet: PKZ18-22 plus gentamicin inhibition of biofilms. ( A ) S. aureus biofilm CFU/log10 after 24 h of a single dose gentamicin, PKZ18-22, and the combination of gentamicin and PKZ18-22. The following asterisk values using a Student’s t -test indicate: * indicates p < 0.05; *** indicates p < 0.001. ( B ) After a single dose 24 h challenge, the combination of gentamicin/PKZ18-22 resulted in a cell reduction of ~5 logs, >99.9%. A significantly greater reduction when compared to each treatment alone.

Article Snippet: Three independent experiments were conducted and required a checkerboard dilution to test various concentrations of the following combinations (PKZ18 analog + each antibiotic) against S. aureus utilizing an established MBECTM-HTP biofilm model (Innovotech) [ , , ].

Techniques: Inhibition

Journal: Gels

Article Title: The Antimicrobial Activity of Micron-Thin Sol–Gel Films Loaded with Linezolid and Cefoxitin for Local Prevention of Orthopedic Prosthesis-Related Infections

doi: 10.3390/gels9030176

Figure Lengend Snippet: Quantification of ( a ) biofilms and ( b ) non-adherent planktonic bacteria of titanium pieces coated with Control, hc.FOX, hc.LNZ, and hc.FOX-LNZ. Data are represented as median and interquartile range of the log 10 (CFU/cm 2 ) estimated by ( a ) drop plate and ( b ) absorbances (absorbance units, AU) obtained in four independent experiments. * p -value < 0.05, ** p -value < 0.01, *** p -value < 0.001 for Wilcoxon test.

Article Snippet: With this medium, the plate lid was replaced with an MBEC TM biofilm incubator lid (Innovotech, Edmonton, AB, Canada) previously prepared with the formulations.

Techniques: Bacteria, Control

Journal: Marine Drugs

Article Title: Marine-Derived Quorum-Sensing Inhibitory Activities Enhance the Antibacterial Efficacy of Tobramycin against Pseudomonas aeruginosa

doi: 10.3390/md13010001

Figure Lengend Snippet: Biofilm prevention assay. 24 h biofilm biomass (mean absorbance of biomass at 590 nm) of P. aeruginosa PAO1 (green) following 24 h exposure to 100 μL of sterile 3-day supernatants of marine isolates ABP4, LL53, LL67, KS6, KS8, JUN4, ISO1, ISO2, ISO4. CM = Conditioned media. Differences in mean absorbance were compared to the untreated control at each time-point and considered significant when p < 0.05 ( * p < 0.05, ** p < 0.01, *** p < 0.001) according to the non-parametric Kruskal Wallis test with Dunn’s Multiple Comparison Test.

Article Snippet: As the crystal violet microtitre plate assay measures biomass but fails to take into account cell viability, the study of the prevention of biofilm formation and biofilm eradication following exposure to the bioactives produced by isolate KS8 was conducted using the Calgary Biofilm Device (CBD, MBECTM assay for Physiology & Genetics, Innovotech, Edmonton, Alberta, Canada).

Techniques: Sterility, Control, Comparison

Journal: Marine Drugs

Article Title: Marine-Derived Quorum-Sensing Inhibitory Activities Enhance the Antibacterial Efficacy of Tobramycin against Pseudomonas aeruginosa

doi: 10.3390/md13010001

Figure Lengend Snippet: Biofilm removal assay. 48 h biofilm biomass (mean absorbance of biomass at 590 nm) of P. aeruginosa (PAO1) biofilms following 24 h challenge using 100 μL of sterile 3-day supernatants of marine isolates ABP4, LL53, LL67, KS6, KS8, JUN4, ISO1, ISO2, ISO4. CM = Conditioned media. Differences in mean absorbance were compared to the untreated control at each time-point and considered significant when p < 0.05 ( * p < 0.05, ** p < 0.01, *** p < 0.001) according to the non-parametric Kruskal Wallis test with Dunn’s Multiple Comparison Test.

Article Snippet: As the crystal violet microtitre plate assay measures biomass but fails to take into account cell viability, the study of the prevention of biofilm formation and biofilm eradication following exposure to the bioactives produced by isolate KS8 was conducted using the Calgary Biofilm Device (CBD, MBECTM assay for Physiology & Genetics, Innovotech, Edmonton, Alberta, Canada).

Techniques: Sterility, Control, Comparison

Journal: Marine Drugs

Article Title: Marine-Derived Quorum-Sensing Inhibitory Activities Enhance the Antibacterial Efficacy of Tobramycin against Pseudomonas aeruginosa

doi: 10.3390/md13010001

Figure Lengend Snippet: Summary of the percent reduction of P. aeruginosa (PAO1) biofilm biomass following 24 h challenge using sterile 72 h KS8 supernatant during biofilm formation and on mature, pre-established 24 h P. aeruginosa (PAO1) biofilms (biofilm removal assay). Differences in mean absorbance compared to the untreated control of each time-point were considered significant when p < 0.05 (* p < 0.05, ** p < 0.01, *** p < 0.001) according to the non-parametric Kruskal Wallis test with Dunn’s Multiple Comparison Test.

Article Snippet: As the crystal violet microtitre plate assay measures biomass but fails to take into account cell viability, the study of the prevention of biofilm formation and biofilm eradication following exposure to the bioactives produced by isolate KS8 was conducted using the Calgary Biofilm Device (CBD, MBECTM assay for Physiology & Genetics, Innovotech, Edmonton, Alberta, Canada).

Techniques: Sterility, Control, Comparison

Journal: Marine Drugs

Article Title: Marine-Derived Quorum-Sensing Inhibitory Activities Enhance the Antibacterial Efficacy of Tobramycin against Pseudomonas aeruginosa

doi: 10.3390/md13010001

Figure Lengend Snippet: Prevention of biofilm formation by isolate KS8 supernatant and determination of the optimal incubation period for bioactive production. P. aeruginosa (PAO1) mean biofilm counts following 24 h exposure to sterile 1-day, 3-day and 10-day supernatants of isolate KS8. PAO1 biofilms were grown on the Calgary Biofilm Device for 24 h in LB broth at 37 °C and 150 rpm. Differences in mean absorbance were compared to the untreated control at each time-point and considered significant when p < 0.05 (* p < 0.05, ** p < 0.01, *** p < 0.001) according to the non-parametric Kruskal Wallis test with Dunn’s Multiple Comparison Test.

Article Snippet: As the crystal violet microtitre plate assay measures biomass but fails to take into account cell viability, the study of the prevention of biofilm formation and biofilm eradication following exposure to the bioactives produced by isolate KS8 was conducted using the Calgary Biofilm Device (CBD, MBECTM assay for Physiology & Genetics, Innovotech, Edmonton, Alberta, Canada).

Techniques: Incubation, Sterility, Control, Comparison

Journal: Marine Drugs

Article Title: Marine-Derived Quorum-Sensing Inhibitory Activities Enhance the Antibacterial Efficacy of Tobramycin against Pseudomonas aeruginosa

doi: 10.3390/md13010001

Figure Lengend Snippet: Biofilm eradication assay. P. aeruginosa PAO1 biofilms were grown on the Calgary Biofilm Device for 24 h in LB broth at 37 °C and 150 rpm prior to challenge. Mean viable biofilm counts obtained following 24 h exposure to 100 μL of sterile 3-day supernatant of isolates ISO1, ISO6, LL67, KS6, KS8, SS1, SS2, and BW23. Each value is expressed as the mean and standard deviation of at least six replicates. Differences in mean absorbance were compared to the untreated control at each time-point and considered significant when p < 0.05 ( * p < 0.05, ** p < 0.01, *** p < 0.001) according to the non-parametric Kruskal Wallis test with Dunn’s Multiple Comparison Test.

Article Snippet: As the crystal violet microtitre plate assay measures biomass but fails to take into account cell viability, the study of the prevention of biofilm formation and biofilm eradication following exposure to the bioactives produced by isolate KS8 was conducted using the Calgary Biofilm Device (CBD, MBECTM assay for Physiology & Genetics, Innovotech, Edmonton, Alberta, Canada).

Techniques: Sterility, Standard Deviation, Control, Comparison

Journal: Marine Drugs

Article Title: Marine-Derived Quorum-Sensing Inhibitory Activities Enhance the Antibacterial Efficacy of Tobramycin against Pseudomonas aeruginosa

doi: 10.3390/md13010001

Figure Lengend Snippet: Biofilm eradication assay. Log 10 bfu/peg biofilm viable counts and percent reduction of pre-established P. aeruginosa (PAO1) biofilms challenged with 100 μL of 3-day supernatant of marine isolate KS8 in the CBD (24 h at 37 °C and 95% relative humidity at 150 rpm). Differences in log 10 (bfu/peg) were considered significant when p < 0.05 (* p < 0.05, ** p < 0.01, *** p < 0.001) according to the non-parametric Kruskal Wallis test with Dunn’s Multiple Comparison Test. Values for the percent reduction in biomass absorbance are also included.

Article Snippet: As the crystal violet microtitre plate assay measures biomass but fails to take into account cell viability, the study of the prevention of biofilm formation and biofilm eradication following exposure to the bioactives produced by isolate KS8 was conducted using the Calgary Biofilm Device (CBD, MBECTM assay for Physiology & Genetics, Innovotech, Edmonton, Alberta, Canada).

Techniques: Comparison

Journal: Marine Drugs

Article Title: Marine-Derived Quorum-Sensing Inhibitory Activities Enhance the Antibacterial Efficacy of Tobramycin against Pseudomonas aeruginosa

doi: 10.3390/md13010001

Figure Lengend Snippet: Scanning electron micrographs of ( A ) P. aeruginosa PAO1 biofilms grown on the CBD for 24 h at 37 °C; ( B ) PAO1 biofilms treated with KS8 8-day supernatant. Pictures were taken using using a field emission scanning electron microscope FE-SEM (JEOL JSM-6500F FE-SEM, JEOL Ltd., Tokyo, Japan).

Article Snippet: As the crystal violet microtitre plate assay measures biomass but fails to take into account cell viability, the study of the prevention of biofilm formation and biofilm eradication following exposure to the bioactives produced by isolate KS8 was conducted using the Calgary Biofilm Device (CBD, MBECTM assay for Physiology & Genetics, Innovotech, Edmonton, Alberta, Canada).

Techniques: Microscopy

Journal: Marine Drugs

Article Title: Marine-Derived Quorum-Sensing Inhibitory Activities Enhance the Antibacterial Efficacy of Tobramycin against Pseudomonas aeruginosa

doi: 10.3390/md13010001

Figure Lengend Snippet: Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum biofilm eradication concentration (MBEC) of the crude organic extract of marine isolate KS8 (mg/mL) against a range of human pathogens associated to indwelling medical device infections.

Article Snippet: As the crystal violet microtitre plate assay measures biomass but fails to take into account cell viability, the study of the prevention of biofilm formation and biofilm eradication following exposure to the bioactives produced by isolate KS8 was conducted using the Calgary Biofilm Device (CBD, MBECTM assay for Physiology & Genetics, Innovotech, Edmonton, Alberta, Canada).

Techniques: Concentration Assay

Journal: Marine Drugs

Article Title: Marine-Derived Quorum-Sensing Inhibitory Activities Enhance the Antibacterial Efficacy of Tobramycin against Pseudomonas aeruginosa

doi: 10.3390/md13010001

Figure Lengend Snippet: ( A ) Production of Pyocyanain (OD695 nm) by P. aeruginosa (PAO1) 48 h biofilms and planktonic cultures following 24 h treatment with KS8 crude organic extract. ( B ) Production of the QS-controlled siderophore Pyoverdine (Excitation 400 nm emission 450 nm/OD600 nm)) by P. aeruginosa (PAO1) 48 h biofilms and planktonic cultures following 24 h treatment with KS8 crude organic extract. Differences in mean absorbance were compared to the untreated control at each time-point and considered significant when p < 0.05 (* p < 0.05, ** p < 0.01, *** p < 0.001) according to the non-parametric Kruskal Wallis test with Dunn’s Multiple Comparison Test.

Article Snippet: As the crystal violet microtitre plate assay measures biomass but fails to take into account cell viability, the study of the prevention of biofilm formation and biofilm eradication following exposure to the bioactives produced by isolate KS8 was conducted using the Calgary Biofilm Device (CBD, MBECTM assay for Physiology & Genetics, Innovotech, Edmonton, Alberta, Canada).

Techniques: Control, Comparison

Journal: BioMed Research International

Article Title: Effects of Fine Particulate Matter on Pseudomonas aeruginosa Adhesion and Biofilm Formation In Vitro

doi: 10.1155/2018/6287932

Figure Lengend Snippet: P. aeruginosa biofilm formation on peg and flat-bottom well after fine particulate matter (FPM) treatment. (a, b) Amounts of biofilm masses were measured with the absorbance value of crystal violet solubilized from the stained biofilm. Biofilm masses on the peg (a) and flat-bottom well (b) increased with an increase in the concentration of FPM in a dose-dependent manner. Contour and architecture of biofilms were examined using scanning electron microscopy. (c) Dense biofilm and cracked surface are observed in the image after treatment with 100 μ g/mL FPM. (d, e) Surface of the peg coated with hydroxyapatite covered with attached bacteria to form a biofilm after treatment with 50 and 25 μ g/mL FPM. (f) Bacteria rarely adhere on the peg surfaces and hydroxyapatite-coated surface can be seen in FPM-untreated cultures.

Article Snippet: Furthermore, the MBECTM Biofilm Inoculator (Innovotech, Edmonton, Canada) pegs coated with hydroxyapatite, facilitating bacterial biofilm growth, were immersed into the bacterial suspension.

Techniques: Staining, Concentration Assay, Electron Microscopy, Bacteria