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Arthur L. Barry

Bio: Arthur L. Barry is an academic researcher from University of California, Davis. The author has contributed to research in topics: Broth microdilution & Antibacterial agent. The author has an hindex of 43, co-authored 323 publications receiving 6945 citations. Previous affiliations of Arthur L. Barry include Centers for Disease Control and Prevention & Cleveland Clinic.


Papers
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TL;DR: In vitro studies were performed comparing ciprofloxacin (Bay o 9867) and norfloxaxacin with three related organic acids as mentioned in this paper, and the results showed that CIPROFLOXACIN was two to eight times more active than NFFACIN against 658 bacterial isolates representing 30 species.
Abstract: In vitro studies were performed comparing ciprofloxacin (Bay o 9867) and norfloxacin with three related organic acids. Ciprofloxacin was two to eight times more active than norfloxacin against 658 bacterial isolates representing 30 species. For all species tested, ciprofloxacin MICs for 90% inhibition were less than or equal to 2.0 micrograms ml. Additional tests with 5,994 isolates detected only 37 (0.6%) strains resistant to 2.0 micrograms of ciprofloxacin per ml and 106 (1.8%) resistant to 1.0 micrograms/ml. Only 6 (0.1%) of the 5,994 strains were resistant to 16 micrograms of norfloxacin per ml, and 129 (2.1%) were resistant to 4.0 micrograms/ml. The majority of resistant strains were streptococci or Pseudomonas spp. Resistance among the Enterobacteriaceae was extremely rare (i.e., greater than 99.8% susceptible to both drugs.

195 citations

Journal ArticleDOI
TL;DR: Stability of these antibiotic-containing discs was studied under conditions of temperature and humidity variation that might be encountered in a clinical laboratory refrigerator, and oxacillin discs were the most stable and are to be preferred for susceptibility testing.
Abstract: The resistance of Staphylococcus aureus to methicillin and related drugs can be reliably determined by using the Kirby-Bauer method of susceptibility testing if the incubation temperature is 35 C or below, but resistance may be missed at 37 C. The 1-mug discs of oxacillin and nafcillin or the 5-mug discs of methicillin may be used for this purpose but not the 1-mug discs of cloxacillin. The latter fail to discriminate between sensitive and resistant staphylococci by zone measurement; some resistant strains of staphylococci may show larger zones of inhibition than sensitive strains. Stability of these antibiotic-containing discs was studied under conditions of temperature and humidity variation that might be encountered in a clinical laboratory refrigerator. Oxacillin discs were the most stable and are to be preferred for susceptibility testing. Nafcillin discs were less stable, and methicillin discs lose their potency rapidly unless carefully stored in a refrigerator with a desiccant.

185 citations

Journal ArticleDOI
TL;DR: The in vitro activity of daptomycin is affected by the concentration of calcium cations in the test medium, and greater concentrations of calcium (50 mg/liter) are recommended to better resemble the normal concentration of ionized calcium in human serum.
Abstract: The in vitro activity of daptomycin is affected by the concentration of calcium cations in the test medium. Mueller-Hinton broth is currently adjusted to contain 10 to 12.5 mg of magnesium per liter and 20 to 25 mg of calcium per liter, but for testing of daptomycin, greater concentrations of calcium (50 mg/liter) are recommended to better resemble the normal concentration of ionized calcium in human serum. Two levels of calcium were used for broth microdilution tests of 2,789 recent clinical isolates of gram-positive bacterial pathogens. MICs of daptomycin were two- to fourfold lower when the broth contained additional calcium. For most species, however, the percentages of strains that were inhibited by 2.0 μg of daptomycin per ml were essentially identical with the two broth media. Enterococci were the important exception; i.e., 92% were inhibited when tested in calcium-supplemented broth but only 35% were inhibited by 2.0 μg/ml without the additional calcium. This type of information should be considered when selecting criteria for defining in vitro susceptibility to daptomycin.

152 citations

Journal ArticleDOI
TL;DR: Of the four drugs tested, daptomycin was bactericidal against the most strains and had the most rapid cidal activity.
Abstract: MICs and minimum bactericidal concentrations (MBCs) of daptomycin, vancomycin, linezolid and quinupristin-dalfopristin (Q-D) were determined for 108 staphylococcal isolates. All strains were susceptible (MICs) to daptomycin (≤2.0 mglL) and Q-D (≤1.0 mg/L). All but three isolates were susceptible to vancomycin (≤4.0 mg/L) and all but one methicillin-resistant Staphylococcus aureus strain were susceptible to linezolid (≤4.0 mg/L). Q-D had the lowest geometric mean MIC (0.29 mg/L) and daptomycin had the lowest geometric mean MBC (0.57 mg/L). Time-kill tests were performed on 25 isolates. Bactericidal activity (>99.9% kill) was observed with daptomycin at 2 mglL and at 2 x MBC for 92% of strains tested. In comparison, the bactericidal rates for the other drugs at breakpoint concentrations and at 2 x MBC were 72% and 70% for vancomycin, 46% and 60% for Q-D, and 7% and 14% for linezolid. Of the four drugs tested, daptomycin was bactericidal against the most strains and had the most rapid cidal activity.

132 citations


Cited by
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Sara A. Burt1
TL;DR: In vitro studies have demonstrated antibacterial activity of essential oils (EOs) against Listeria monocytogenes, Salmonella typhimurium, Escherichia coli O157:H7, Shigella dysenteria, Bacillus cereus and Staphylococcus aureus at levels between 0.2 and 10 microl ml(-1).

9,091 citations

01 Jan 1990

1,648 citations

Journal ArticleDOI
TL;DR: This comprehensive State of the Art review summarizes the current published knowledge base regarding the pathophysiology and microbiology of pulmonary disease in cystic fibrosis and potential future therapies.
Abstract: This comprehensive State of the Art review summarizes the current published knowledge base regarding the pathophysiology and microbiology of pulmonary disease in cystic fibrosis (CF). The molecular basis of CF lung disease including the impact of defective cystic fibrosis transmembrane regulator (CFTR) protein function on airway physiology, mucociliary clearance, and establishment of Pseudomonas aeruginosa infection is described. An extensive review of the microbiology of CF lung disease with particular reference to infection with P. aeruginosa is provided. Other pathogens commonly associated with CF lung disease including Staphylococcal aureus, Burkholderia cepacia, Stenotrophomonas maltophilia, Achromobacter xylosoxidans and atypical mycobacteria are also described. Clinical presentation and assessment of CF lung disease including diagnostic microbiology and other measures of pulmonary health are reviewed. Current recommendations for management of CF lung disease are provided. An extensive review of antipseudomonal therapies in the settings of treatment for early P. aeruginosa infection, maintenance for patients with chronic P. aeruginosa infection, and treatment of exacerbation in pulmonary symptoms, as well as antibiotic therapies for other CF respiratory pathogens, are included. In addition, the article discusses infection control policies, therapies to optimize airway clearance and reduce inflammation, and potential future therapies.

1,595 citations

Journal ArticleDOI
TL;DR: This review will focus on the emergence of antimicrobial resistance in S. aureus, the leading overall cause of nosocomial infections and, as more patients are treated outside the hospital setting, is an increasing concern in the community.
Abstract: In the early 1970s, physicians were finally forced to abandon their belief that, given the vast array of effective antimicrobial agents, virtually all bacterial infections were treatable. Their optimism was shaken by the emergence of resistance to multiple antibiotics among such pathogens as Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Mycobacterium tuberculosis. The evolution of increasingly antimicrobial-resistant bacterial species stems from a multitude of factors that includes the widespread and sometimes inappropriate use of antimicrobials, the extensive use of these agents as growth enhancers in animal feed, and, with the increase in regional and international travel, the relative ease with which antimicrobial-resistant bacteria cross geographic barriers (1–3). The irony of this trend toward progressively more resistant bacteria is that it coincides with a period of dramatically increased understanding of the molecular mechanisms of antimicrobial resistance. Unfortunately, while this insight has resulted in the identification of novel drug targets, it has not yet resulted in effective new chemotherapeutic agents. This paradox stands in sharp contrast to the dramatic progress made in antiviral (notably antiretroviral) therapy in the past ten years, where a number of newly discovered molecular targets have resulted in clinically effective therapeutic agents. Nowhere has this issue been of greater concern than with the Gram-positive bacteria pneumococci, enterococci, and staphylococci. Multidrug resistance is now the norm among these pathogens. S. aureus is perhaps the pathogen of greatest concern because of its intrinsic virulence, its ability to cause a diverse array of life-threatening infections, and its capacity to adapt to different environmental conditions (4, 5). The mortality of S. aureus bacteremia remains approximately 20–40% despite the availability of effective antimicrobials (6). S. aureus is now the leading overall cause of nosocomial infections and, as more patients are treated outside the hospital setting, is an increasing concern in the community (7, 8). S. aureus isolates from intensive care units across the country and from blood culture isolates worldwide are increasingly resistant to a greater number of antimicrobial agents (4, 8). Inevitably this has left fewer effective bactericidal antibiotics to treat these often life-threatening infections (Figure ​(Figure1).1). As rapidly as new antibiotics are introduced, staphylococci have developed efficient mechanisms to neutralize them (Table ​(Table11). Figure 1 S. aureus infections in intensive care units in the National Nosocomial Infections Surveillance System. Data include the total number of infections from 1987 to 1997. Isolates were tested for sensitivity to the following antimicrobial agents: gentamicin, ... Table 1 Mechanisms of S. aureus resistance to antimicrobialsA Recent reports of S. aureus isolates with intermediate or complete resistance to vancomycin portend a chemotherapeutic era in which effective bactericidal antibiotics against this organism may no longer be readily available (9, 10). This review will focus on the emergence of antimicrobial resistance in S. aureus. It will review the historical evolution of resistant strains, their spread, the molecular mechanisms of resistance for selected antibiotics, and progress toward the development of alternative drug targets or novel approaches for therapeutic or prophylactic intervention.

1,382 citations

Journal ArticleDOI
TL;DR: Daptomycin (6 mg per kilogram daily) is not inferior to standard therapy for S. aureus bacteremia and right-sided endocarditis and met prespecified criteria for the noninferiority of daptomecin.
Abstract: Background Alternative therapies for Staphylococcus aureus bacteremia and endocarditis are needed. Methods We randomly assigned 124 patients with S. aureus bacteremia with or without endocarditis to receive 6 mg of daptomycin intravenously per kilogram of body weight daily and 122 to receive initial low-dose gentamicin plus either an antistaphylococcal penicillin or vancomycin. The primary efficacy end point was treatment success 42 days after the end of therapy. Results Forty-two days after the end of therapy in the modified intention-to-treat analysis, a successful outcome was documented for 53 of 120 patients who received daptomycin as compared with 48 of 115 patients who received standard therapy (44.2 percent vs. 41.7 percent; absolute difference, 2.4 percent; 95 percent confidence interval, −10.2 to 15.1 percent). Our results met prespecified criteria for the noninferiority of daptomycin. The success rates were similar in subgroups of patients with complicated bacteremia, right-sided endocarditis, a...

1,318 citations