scispace - formally typeset
Search or ask a question
Topic

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.


Papers
More filters
Journal ArticleDOI
TL;DR: All four experimental quinolones as well as RP 59500 show promise for therapy of infections with penicillin-resistant and -susceptible pneumococci.
Abstract: The MICs of four new quinolones, sparfloxacin (AT-4140, CI-978), PD 131628 (the active form of the prodrug CI-990), temafloxacin, and Win 57273, compared with those of ciprofloxacin and ofloxacin were tested against 53 penicillin-susceptible, 35 penicillin intermediate-resistant, and 51 penicillin-resistant pneumococci. Susceptibility to RP 59500, a new streptogramin, was also tested and compared with those to the quinolones, erythromycin, and vancomycin. All MICs were determined by a standardized agar dilution method by using Mueller-Hinton agar supplemented with sheep blood. Quinolone, vancomycin, and RP 59500 susceptibilities were not affected by susceptibility or resistance to penicillin. For Win 57273, the MICs for 50% (MIC50) and 90% (MIC90) of strains tested were 0.015 and 0.03 micrograms/ml, respectively. MIC50S of both sparfloxacin and PD 131628 were 0.25 micrograms/ml, and MIC90S were 0.5 micrograms/ml. The MIC50 of temafloxacin was 0.5 micrograms/ml, and the MIC90 was 1.0 micrograms/ml. By comparison, ofloxacin and ciprofloxacin both yielded MIC50S of 1.0 micrograms/ml and MIC90s of 2.0 micrograms/ml. RP 59500 yielded an MIC50 of 0.5 microgram/ml and an MIC90 of 1.0 microgram/ml and was only 1 doubling dilution less active against 17 erythromycin-resistant strains. Vancomycin was active against all strains (MIC50, 0.25 microgram/ml; MIC90, 0.5 microgram/ml). All four experimental quinolones as well as RP 59500 show promise for therapy of infections with penicillin-resistant and -susceptible pneumococci.

84 citations

Journal ArticleDOI
TL;DR: Combined parenteral and intramammary treatment of mastitis caused by Staphylococcus aureus was compared to parenteal treatment only and combined treatment was superior over systemic treatment only in the β-lactamase negative group.
Abstract: Combined parenteral and intramammary treatment of mastitis caused by Staphylococcus aureus was compared to parenteral treatment only. Cows with clinical mastitis (166 mastitic quarters) caused by S. aureus treated by veterinarians of the Ambulatory Clinic of the Faculty of Veterinary Medicine during routine farm calls were included. Treatment was based on in vitro susceptibility testing of the bacterial isolate. Procaine penicillin G (86 cases due to β-lactamase negative strains) or amoxycillin-clavulanic acid (24 cases due to β-lactamase positive strains) was administered parenterally and intramammarily for 5 days. Efficacy of treatments was assessed 2 and 4 weeks later by physical examination, bacteriological culture, determination of CMT, somatic cell count and NAGase activity in milk. Quarters with growth of S. aureus in at least one post-treatment sample were classified as non-cured. As controls we used 41 clinical mastitis cases caused by penicillin-susceptible S. aureus isolates treated with procaine penicillin G parenterally for 5 days and 15 cases due to penicillin-resistant isolates treated with spiramycin parenterally for 5 days from the same practice area. Bacteriological cure rate after the combination treatment was 75.6% for quarters infected with penicillin-susceptible S. aureus isolates, and 29.2% for quarters infected with penicillin-resistant isolates. Cure rate for quarters treated only parenterally with procaine penicillin G was 56.1% and that for quarters treated with spiramycin 33.3%. The difference in cure rates between mastitis due to penicillin-susceptible and penicillin-resistant S. aureus was highly significant. Combined treatment was superior over systemic treatment only in the β-lactamase negative group.

83 citations

Journal ArticleDOI
08 Jun 1996-BMJ
TL;DR: Resistance to penicillin and erythromycin has increased among pneumococci in England and Wales and continued surveillance to assess further increases in the prevalence of pneumococcal resistance to antibiotics is essential.
Abstract: Objective: To assess the prevalence of antibiotic resistance and serotype distribution among pneumococci in England and Wales in 1990 and 1995. Design: Observational surveys in March 1990 and March 1995. During two weeks in each survey period all pneumococci isolated in public health laboratories in England and Wales were collected and assessed for sensitivity to antibiotics and the distribution of serogroups or serotypes. Setting: The network of public health laboratories throughout England and Wales. Subjects: 1127 individual patient isolates of Streptococcus pneumoniae obtained during the two surveys. Main outcome measures: Sensitivity or resistance to a range of antibiotics; serogroup or serotype. Results: The prevalence of intermediate or full resistance to penicillin increased from 1.5% in 1990 to 3.9% in 1995 and resistance to erythromycin increased from 2.8% to 8.6%. About 92% of isolates belonged to serogroups or serotypes included in the currently available pneumococcal vaccine. Conclusion: Resistance to penicillin and erythromycin has increased among pneumococci in England and Wales. Continued surveillance to assess further increases in the prevalence of pneumococcal resistance to antibiotics is essential. Key messages Resistance to cefotaxime or ceftriaxone, which may be the drugs of choice for pneumococcal meningitis caused by penicillin resistant pneumo- cocci, is still fairly rare Roughly 92% of pneumococcal isolates in England and Wales belong to serogroups or serotypes included in the currently available 23 valent vaccine Between 65.1% and 73.9% of pneumococcal isolates from children aged 2 or less belong to sero- groups or serotypes included in the five, seven, or nine valent conjugate vaccines under development for use in children of this age group Continued surveillance of pneumococcal resist- ance to antibiotics is essential if clinicians are to make rational decisions concerning the treatment of pneumococcal infections

83 citations

Journal ArticleDOI
TL;DR: It is concluded that penicillin has little effect on clinical outcome in icteric leptospirosis.
Abstract: A prospective, controlled randomized study of penicillin therapy in icteric human leptospirosis was carried out between 1 October 1983 and 31 December 1986. Thirty-eight patients received intravenous crystalline penicillin for 5 days, while 41 assigned to a control group received intravenous fluids only. A comparison of the results of laboratory tests made on the day of admission revealed no significant differences between the 2 groups. There was no significant difference in time for defervescence, return of biochemical parameters to normal, incidence of iritis, or mortality in the 2 groups. Three patients (7.3%) in the control group and 1 patient (2.6%) in the treatment group died. The overall mortality rate was 5.9%. Leptospira were recovered from urine cultures in 6 control patients but from none of the treated patients' post-treatment cultures. We conclude that penicillin has little effect on clinical outcome in icteric leptospirosis.

83 citations

Journal ArticleDOI
TL;DR: It is suggested that subminimal inhibitory concentrations of antibiotics suppress the ability of bacteria to adhere to cells.
Abstract: Nonseptate filaments of Escherichia coli obtained by growth of a temperature-sensitive mutant of the organism at its restrictive temperature in the absence of antibiotics or at its permissive temperature in the presence of approximately one-half the MIC of penicillin (27 micrograms/ml; MIC of penicillin, 50 micrograms/ml) lacked the ability both to bind to mannose and to adhere to host tissues. Addition of low concentrations (0.5-10 micrograms/ml) of streptomycin to cultures of E. coli resulted in marked suppression of the mannose-binding and adhering ability of streptomycin-sensitive E. coli (MIC, 30 micrograms/ml). In contrast, up to 5,000 microgram of streptomycin/ml had no effect on an isogenic streptomycin-resistant mutant of E. coli (MIC, 20,000 micrograms/ml). No concentration of penicillin or streptomycin that was tested was able to suppress either the mannose-binding or the adhering ability of E. coli once those activities had been acquired by the organism. These results suggest that subminimal inhibitory concentrations of antibiotics suppress the ability of bacteria to adhere to cells.

83 citations


Network Information
Related Topics (5)
Staphylococcus aureus
27K papers, 779K citations
82% related
Tuberculosis
66.6K papers, 1.3M citations
81% related
Antibiotic resistance
29.1K papers, 884.5K citations
81% related
Antibacterial agent
35.8K papers, 1.2M citations
80% related
Drug resistance
28.4K papers, 1.1M citations
80% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023459
2022907
2021249
2020269
2019221
2018192