scholarly journals In VitroActivities of Tedizolid and Linezolid against Gram-Positive Cocci Associated with Acute Bacterial Skin and Skin Structure Infections and Pneumonia

2015 ◽  
Vol 59 (10) ◽  
pp. 6262-6265 ◽  
Author(s):  
Ko-Hung Chen ◽  
Yu-Tsung Huang ◽  
Chun-Hsing Liao ◽  
Wang-Hui Sheng ◽  
Po-Ren Hsueh

ABSTRACTTedizolid is a novel, expanded-spectrum oxazolidinone with potent activity against a wide range of Gram-positive pathogens. A total of 425 isolates of Gram-positive bacteria were obtained consecutively from patients with acute bacterial skin and skin structure infections (ABSSSIs) or pneumonia. These isolates included methicillin-susceptibleStaphylococcus aureus(MSSA) (n= 100), methicillin-resistantStaphylococcus aureus(MRSA) (n= 100),Streptococcus pyogenes(n= 50),Streptococcus agalactiae(n= 50),Streptococcus anginosusgroup (n= 75),Enterococcus faecalis(n= 50), and vancomycin-resistant enterococci (VRE) (Enterococcus faecium) (n= 50). The MICs of tedizolid and linezolid were determined by the agar dilution method. Tedizolid exhibited betterin vitroactivities than linezolid against MSSA (MIC90s, 0.5 versus 2 μg/ml), MRSA (MIC90s, 0.5 versus 2 μg/ml),S. pyogenes(MIC90s, 0.5 versus 2 μg/ml),S. agalactiae(MIC90s, 0.5 versus 2 μg/ml),Streptococcus anginosusgroup (MIC90s, 0.5 versus 2 μg/ml),E. faecalis(MIC90s, 0.5 versus 2 μg/ml), and VRE (MIC90s, 0.5 versus 2 μg/ml). The tedizolid MICs againstE. faecalis(n= 3) and VRE (n= 2) intermediate to linezolid (MICs, 4 μg/ml) were 1 μg/ml and 0.5 μg/ml, respectively. The tedizolid MIC90s against S. anginosus,S. constellatus, andS. intermediuswere 0.5, 1, and 0.5 μg/ml, respectively, and the rates of susceptibility based on the U.S. FDA MIC interpretive breakpoints to the isolates were 16%, 28%, and 72%, respectively. Tedizolid exhibited 2- to 4-fold betterin vitroactivities than linezolid against a variety of Gram-positive cocci associated with ABSSSIs and pneumonia. The lower susceptibilities of tedizolid against isolates ofS. anginosusandS. constellatusthan against those ofS. intermediusin Taiwan were noted.

2016 ◽  
Vol 54 (9) ◽  
pp. 2225-2232 ◽  
Author(s):  
Matthew P. Crotty ◽  
Tamara Krekel ◽  
Carey-Ann D. Burnham ◽  
David J. Ritchie

The growing problem of antimicrobial resistance among bacterial pathogens, including methicillin-resistantStaphylococcus aureus(MRSA) and vancomycin-resistant enterococci (VRE), has reached a critical state. Tedizolid phosphate, dalbavancin, and oritavancin have recently been approved by the U.S. Food and Drug Administration (FDA) for the treatment of acute bacterial skin and skin structure infections (ABSSSI) and represent the next generation of oxazolidinones and lipoglycopeptides. All three agents exhibitin vitroactivity and clinical efficacy against MRSA. Tedizolid phosphate and oritavancin demonstratein vitroactivity against VRE. These new Gram-positive agents are reviewed here.


2003 ◽  
Vol 47 (11) ◽  
pp. 3667-3671 ◽  
Author(s):  
A. Liebetrau ◽  
A. C. Rodloff ◽  
J. Behra-Miellet ◽  
L. Dubreuil

ABSTRACT The antimicrobial activities of garenoxacin and eight other antibiotics against 641 anaerobic isolates were evaluated with the NCCLS agar dilution method. Overall, the MICs of garenoxacin for 50 and 90% of the strains tested (in micrograms per milliliter) were as follows: Bacteroides fragilis group, 0.5 and 2; Prevotella spp., 0.25 and 2; Fusobacterium spp., 0.25 and 0.5; Porphyromonas spp., 0.125 and 0.25; Bilophila wadsworthia, 0.5 and 1; Veillonella spp., 0.25 and 0.5; Clostridium spp., 0.25 and 1; Clostridium difficile, 2 and >64; Bifidobacterium spp., 1 and 2; Eggerthella lenta, 0.25 and 1; Propionibacterium spp., 0.5 and 0.5; gram-positive cocci, 0.125 and 0.25.


2019 ◽  
Vol 63 (4) ◽  
Author(s):  
Stephanie Noviello ◽  
Sophie Magnet ◽  
Stephen Hawser ◽  
David B. Huang

ABSTRACT Iclaprim, a selective bacterial dihydrofolate reductase inhibitor, and other antibiotics were tested against Gram-positive isolates from two phase 3 studies of acute bacterial skin and skin structure infections (ABSSSIs) (REVIVE-1 and -2). Seven hundred ninety baseline isolates, including Staphylococcus aureus, β-hemolytic streptococci, and Streptococcus anginosus group, underwent antibacterial susceptibility testing. Iclaprim had an MIC90 of 0.12 μg/ml for S. aureus (0.12 μg/ml for methicillin susceptible, 0.25 μg/ml for methicillin resistant), 0.25 μg/ml for β-hemolytic streptococci, and 0.008 μg/ml for S. anginosus group. Iclaprim demonstrated potent activity against these Gram-positive ABSSSI isolates.


2011 ◽  
Vol 55 (7) ◽  
pp. 3631-3634 ◽  
Author(s):  
David J. Farrell ◽  
Lisa C. Liverman ◽  
Douglas J. Biedenbach ◽  
Ronald N. Jones

ABSTRACTJNJ-Q2 is a broad-spectrum bactericidal fluoroquinolone with potent activity against Gram-positive and -negative pathogens. In this study, thein vitroactivity of JNJ-Q2 was evaluated against 511 selectedStaphylococcus aureussamples isolated in 2008-2009 from patients with acute bacterial skin and skin structure infections in the United States by using reference methodology. JNJ-Q2 was the most potent fluoroquinolone tested overall (MIC50and MIC90, 0.12 and 0.5 μg/ml, respectively) and against methicillin- and fluoroquinolone-resistant subgroups in direct comparisons to moxifloxacin, levofloxacin, and ciprofloxacin (each being ≥16-fold less potent than JNJ-Q2).


2011 ◽  
Vol 8 (3) ◽  
pp. 1120-1123 ◽  
Author(s):  
Bahram Letafat ◽  
Negar Mohammadhosseini ◽  
Ali Asadipour ◽  
Alireza Foroumadi

In the present study we report the synthesis and antibacterial activity of a new series 2-(1-methyl-4-nitro-1H-imidazol-5-ylsulfonyl)-1,3,4-thiadiazoles (6a-c). Compounds6a-cwere testedin vitroby the conventional agar dilution method against a panel of microorganisms including gram-negative and gram-positive bacteria. Compound6bwith 5-(5-nitrofuran-2-yl)-residue on 1,3,4-thiadiazole scaffold have shown promising antibacterial activities against gram-positive bacteria includingStaphylococcus aureus, Staphylococcus epidermidisandBacillus subtilis.


2019 ◽  
Vol 63 (4) ◽  
Author(s):  
Hongmin Zhang ◽  
Susu Liu ◽  
Juan Yue ◽  
Shengtao Sun ◽  
Qixue Lv ◽  
...  

ABSTRACT Bacterial keratitis is an aggressive infectious corneal disease. With the continuing rise in antibiotic resistance and a decline in the discovery of new antibiotics, new antimicrobial drugs are now required. In the present study, we determined the antibacterial activity of diacerein, an anti-inflammatory drug, against 76 Gram-positive cocci isolated from bacterial keratitis patients in vitro and anti-Staphylococcus aureus activity in a mouse bacterial keratitis model in vivo. The MICs of diacerein were tested using the broth microdilution method in vitro. A BALB/c Staphylococcus aureus keratitis animal model was selected and the corneal clinical observation, viable bacteria, and hematoxylin-eosin and Gram staining of infected corneas were measured to evaluate the antibacterial efficacy of diacerein eye drops in vivo. An in vivo eye irritation study was carried out by a modified Draize test in rabbits. Our in vitro results showed that diacerein possesses satisfactory antibacterial activity against the majority of Gram-positive cocci (60/76), including all 57 tested Staphylococcus spp. and 3 Enterococcus spp. The in vivo experiment showed that diacerein eye drops reduced bacterial load and improved ocular clinical scores after topical administration of diacerein drops on infected corneas. The ocular irritation test revealed that diacerein eye drop had excellent ocular tolerance. These results indicated that diacerein possesses in vivo anti-Staphylococcus aureus activity. We suggest that diacerein is a possible topically administered drug for Staphylococcus aureus-infected patients, especially those with ocular surface inflammatory disorders.


2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Séverine Boisard ◽  
Anne-Marie Le Ray ◽  
Anne Landreau ◽  
Marie Kempf ◽  
Viviane Cassisa ◽  
...  

During this study, thein vitroantifungal and antibacterial activities of different extracts (aqueous and organic) obtained from a French propolis batch were evaluated. Antifungal activity was evaluated by broth microdilution on three pathogenic strains:Candida albicans, C. glabrata, andAspergillus fumigatus. Antibacterial activity was assayed using agar dilution method on 36 Gram-negative and Gram-positive strains includingStaphylococcus aureus. Organic extracts showed a significant antifungal activity againstC. albicansandC. glabrata(MIC80between 16 and 31 µg/mL) but only a weak activity towardsA. fumigatus(MIC80= 250 µg/mL). DCM based extracts exhibited a selective Gram-positive antibacterial activity, especially againstS. aureus(SA) and several of its methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) strains (MIC10030–97 µg/mL). A new and active derivative of catechin was also identified whereas a synergistic antimicrobial effect was noticed during this study.


Author(s):  
SAPANA SHARMA ◽  
UPASHANA BHANDARI ◽  
YOGESH OLI ◽  
GANESH BHANDARI ◽  
SUNITA BISTA ◽  
...  

Objectives: The main aim of this work is to determine the antibiogram profile of biofilm-producing Staphylococcus aureus from various clinical specimens of the patients. Methods: Various bacterial cultures of non-repeated clinical specimens from a total of 3388 patients were determined using standard microbiological and biochemical methods. Results: Out of 3388 only 604 (17.02%) displayed growth positive. A total of 65 (51.58%) S. aureus isolates were recovered, 25 (38.46%) were identified as methicillin-resistant S. aureus (MRSA) by Cefoxitin (30 μg) disk diffusion technique, of which majority were from pus/wound swab 22 (37.29%). The antibiogram of the isolates was analyzed by Kirby-Bauer disk diffusion technique analyzing Linezolid to be the most effective drug with susceptibility of 100% to both MRSA and methicillin-sensitive S. aureus, followed by vancomycin, tigecycline, and tetracycline. In vitro biofilm production by tissue culture plate (TCP) and Congo red agar method detected 52 (80%) and 25 (38.46%) as biofilm producers, respectively. TCP identified 2 (3.07%), 7 (10.76%), and 44 (67.69%) as strongly, moderately, and weakly adherent. About 30.7% of MRSA obtained were positive biofilm producers. The minimum inhibitory concentration value of Oxacillin for S. aureus by agar dilution method ranged from 0.025 μg/mL to 128 μg/mL. Conclusion: This study shows that biofilm production was more in methicillin-resistant strains and displayed a high degree of resistance to almost all groups of antibiotics.


mBio ◽  
2011 ◽  
Vol 2 (3) ◽  
Author(s):  
Olaya Rendueles ◽  
Laetitia Travier ◽  
Patricia Latour-Lambert ◽  
Thierry Fontaine ◽  
Julie Magnus ◽  
...  

ABSTRACTBacterial biofilms often form multispecies communities in which complex but ill-understood competition and cooperation interactions occur. In light of the profound physiological modifications associated with this lifestyle, we hypothesized that the biofilm environment might represent an untapped source of natural bioactive molecules interfering with bacterial adhesion or biofilm formation. We produced cell-free solutions extracted fromin vitromature biofilms formed by 122 naturalEscherichia coliisolates, and we screened these biofilm extracts for antiadhesion molecules active on a panel of Gram-positive and Gram-negative bacteria. Using this approach, we showed that 20% of the tested biofilm extracts contained molecules that antagonize bacterial growth or adhesion. We characterized a compound, produced by a commensal animalE. colistrain, for which activity is detected only in biofilm extract. Biochemical and genetic analyses showed that this compound corresponds to a new type of released high-molecular-weight polysaccharide whose biofilm-associated production is regulated by the RfaH protein. We demonstrated that the antiadhesion activity of this polysaccharide was restricted to Gram-positive bacteria and that its production reduced susceptibility to invasion and provided rapid exclusion ofStaphylococcus aureusfrom mixedE. coliandS. aureusbiofilms. Our results therefore demonstrate that biofilms contain molecules that contribute to the dynamics of mixed bacterial communities and that are not or only poorly detected in unconcentrated planktonic supernatants. Systematic identification of these compounds could lead to strategies that limit pathogen surface colonization and reduce the burden associated with the development of bacterial biofilms on medical devices.IMPORTANCEWe sought to demonstrate that bacterial biofilms are reservoirs for unknown molecules that antagonize bacterial adhesion. The use of natural strains representative ofEscherichia colispecies biodiversity showed that nonbiocidal antiadhesion polysaccharides are frequently found in mature biofilm extracts (bacterium-free suspensions which contain soluble molecules produced within the biofilm). Release of an antiadhesion polysaccharide confers a competitive advantage upon the producing strain against clinically relevant pathogens such asStaphylococcus aureus. Hence, exploring the biofilm environment provides a better understanding of bacterial interactions within complex communities and could lead to improved control of pathogen colonization.


2019 ◽  
Vol 64 (1) ◽  
Author(s):  
Anthony D. Verderosa ◽  
Rabeb Dhouib ◽  
Kathryn E. Fairfull-Smith ◽  
Makrina Totsika

ABSTRACT Treatment of biofilm-related Staphylococcus aureus infections represents an important medical challenge worldwide, as biofilms, even those involving drug-susceptible S. aureus strains, are highly refractory to conventional antibiotic therapy. Nitroxides were recently shown to induce the dispersal of Gram-negative biofilms in vitro, but their action against Gram-positive bacterial biofilms remains unknown. Here, we demonstrate that the biofilm dispersal activity of nitroxides extends to S. aureus, a clinically important Gram-positive pathogen. Coadministration of the nitroxide CTEMPO (4-carboxy-2,2,6,6-tetramethylpiperidin-1-yloxyl) with ciprofloxacin significantly improved the biofilm eradication activity of the antibiotic against S. aureus. Moreover, covalently linking the nitroxide to the antibiotic moiety further reduced the ciprofloxacin minimal biofilm eradication concentration. Microscopy analysis revealed that fluorescent nitroxide-antibiotic hybrids could penetrate S. aureus biofilms and enter cells localized at the surface and base of the biofilm structure. No toxicity to human cells was observed for the nitroxide CTEMPO or the nitroxide-antibiotic hybrids. Taken together, our results show that nitroxides can mediate the dispersal of Gram-positive biofilms and that dual-acting biofilm eradication antibiotics may provide broad-spectrum therapies for the treatment of biofilm-related infections.


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