Penicillin

About: Penicillin is a research topic. Over the lifetime, 17916 publications have been published within this topic receiving 368480 citations. The topic is also known as: penicillin antibiotic & PCN.

Antimicrobial resistance in the subgingival microflora in patients with adult periodontitis. A comparison between The Netherlands and Spain.

Abstract: Background: The widespread use of antibiotics for prophylaxis and treatment of bacterial infections has lead to the emergence of resistant human pathogens Great differences have been documented between European countries in the use of systemic antibiotics In parallel, significant differences in levels of resistant pathogens have been documented Aim: To investigate whether differences in antibiotic use influence the level of antimicrobial resistance of the subgingival microflora of untreated patients with adult periodontitis in The Netherlands and Spain Method: Blood agar plates containing breakpoint concentrations of penicillin, amoxicillin, amoxicillin and clavunalate, metronidazole, erythromycin, azithromycin, clindamycin and tetracycline were used to determine the proportion of bacteria from the subgingival plaque that was resistant to these antibiotics In the Spanish patients, statistically significant higher mean levels of resistance were found for penicillin, amoxicillin, metronidazole, clindamycin and tetracycline The mean number of different bacterial species growing on the selective plates was higher in the Spanish patients, as was the % of resistant strains of most periodontal pathogens A striking difference was observed in the frequency of occurrence of tetracycline-resistant periodontal pathogens In Spain, 5 patients had greater than or equal to 3 tetracycline resistant periodontal pathogens, whereas this was not observed in any of the Dutch patients Conclusions: The widespread use of antibiotics in Spain is reflected in the level of resistance of the subgingival microflora of adult patients with periodontitis

Immediate allergic reactions to cephalosporins: cross-reactivity and selective responses.

Abstract: Background: After penicillins, cephalosporins are the most important β-lactams inducing IgE-mediated reactions. Responses may be selective or cross-reactive with common βlactam determinants. Unlike determinants derived from benzylpenicillin, cephalosporin allergenic determinants have not been properly identified, even though a wide variety of these βlactams is currently used. Objective: We sought to evaluate the IgE response in subjects with immediate allergic reactions to injectable cephalosporins and to assess their reactivity to different penicillins and cephalosporins. Methods: We studied 30 subjects with immediate reactions to one or more of the following cephalosporins: ceftriaxone, cefotaxime, ceftazidime, and cefuroxime. Skin tests and in vitro‐specific IgE antibody assays were performed for major and minor determinants of penicillin G, amoxicillin, and ampicillin, as well as for the culprit cephalosporins. Responses to cephalosporins other than the culprit ones were also studied by using skin testing. Results: Twenty-six patients (group A, 86.7%) displayed skin test and RAST negativity to penicillin determinants and skin test positivity to cephalosporins, with RAST confirmation in 9 patients. Four subjects (group B, 13.3%) had a positive response to penicillin determinants. In group A two patterns of reactivity were observed: one characterized by a response only to the culprit cephalosporin (n = 15, 57.7%) and the other by positive responses to different cephalosporins, including the responsible cephalosporins (n = 11, 42.3%). Conclusion: Most patients with a history of immediate reactions to cephalosporins are sensitized to determinants generated only by cephalosporins (group A), although a small percentage react to penicillin determinants (group B). Some patients from group A responded only to the culprit cephalosporin, but others reacted to different cephalosporins. These findings can be explained in terms of either selective response to unique determinants or cross-reactivity. (J Allergy Clin Immunol 2000;106:1177-83.)

Evolution of Natural Resistance to the Newer Penicillins

Abstract: We wish to thank Dr. E. T. Knudsen, of Beecham Research Laboratories, for the generous supply of methicillin. Our thanks are also due to Dr. I. A. Tounjer and Sisters B. M. Shelton and P. J. Gower for their very efficient ward work. We also thank Mr. G. L. C. Usher, the chief technician, Mr. V. van Geersdaele, the senior laboratory technician, and their staff for dealing with the increased bacteriological work.

Amoxycillin: a new semi-synthetic penicillin.

Abstract: Amoxycillin (alpha-amino-p-hydroxybenzylpenicillin) is a new semi-synthetic penicillin with a broad spectrum of antibacterial activity similar to that of ampicillin. Penicillin-sensitive strains of staphylococci, streptococci, and pneumococci were sensitive to concentrations of 0.1 mug or less of amoxycillin/ml. Strains of Haemophilus influenzae were inhibited by a level of 0.5 mug/ml, and most strains of Escherichia coli, Proteus mirabilis, Shigella sonnei, Salmonella species, and Streptococcus faecalis were sensitive to a concentration of 5 mug or less of amoxycillin/ml. Penicillinase-producing strains of Staphylococcus aureus and strains of Pseudomonas aeruginosa, indole-positive Proteus, Klebsiella, and Enterobacter were insensitive to amoxycillin. The new penicillin was bactericidal in activity, as with other penicillins, and its antibacterial activity was not reduced in the presence of serum. After oral administration to volunteer subjects amoxycillin produced serum concentrations twice as high as those obtained with similar doses of ampicillin, and the penicillin was recovered unchanged in high concentrations in the urine. The absorption of amoxycillin was not greatly influenced by food, and administration of probenecid resulted in increased and more prolonged concentrations of amoxycillin in serum.