-
Thorax Mar 1970An investigation was undertaken to discover whether a single intramuscular dose of long-acting (or mixed long-acting and crystalline) penicillin or a single day's...
An investigation was undertaken to discover whether a single intramuscular dose of long-acting (or mixed long-acting and crystalline) penicillin or a single day's therapy with oral penicillin was satisfactory treatment for lobar pneumonia. These treatments were compared with standard hospital oral and injection therapies. All the experimental treatment regimes were found to be satisfactory. They provide justification for treating lobar pneumonia on an out-patient basis in order to save hospital admissions.
Topics: Adult; Ampicillin; Delayed-Action Preparations; Female; Histamine H1 Antagonists; Humans; Injections, Intramuscular; Jaundice; Male; Penicillin G; Penicillin G Procaine; Penicillins; Pleural Effusion; Pneumonia, Pneumococcal; Radiography; Sputum
PubMed: 4392585
DOI: 10.1136/thx.25.2.241 -
Sante (Montrouge, France) 1999Congenital syphilis is responsible for a variety of clinical symptoms, from subclinical attacks to septicemic forms that may be fatal. The most frequently encountered... (Comparative Study)
Comparative Study Review
Congenital syphilis is responsible for a variety of clinical symptoms, from subclinical attacks to septicemic forms that may be fatal. The most frequently encountered forms typically involve low birth weight, heptosplenomegaly and jaundice. Premature birth, anemia, cutaneous lesions, coryza, anasarca and pseudoparalysis may also occur. Neonatal X rays generally show characteristic but nonspecific osteochondrocyte lesions and periosteous dystrophy. A clinical form partly associated with growing tissues may be detected late. Diagnosis of fetal syphilis depends on the detection by immunofluorescence of specific IgM immunoglobulins in the newborn. Parenteral antibiotic treatment with 100,000 IU penicillin/kg.day for 15 days is given to newborns with symptoms. The classification and treatment of asymptomatic forms is unclear. A single injection of benzathine-penicillin is a good compromise between simple surveillance and admission to hospital for 10 days of intravenous treatment. In any case, serological surveillance is required to check that IgM disappears from the blood or that the titer of IgG decreases. Reinfection is always possible, even in a newborn treated correctly. In developing countries, pediatricians must be aware of the various clinical forms of congenital syphilis. In addition, national programs to combat sexually transmitted diseases should be supported and developed by international aid agencies. In economically advanced countries, attention is currently focused on the restricted nature of medical treatment. Improvements in the management of congenital syphilis depend above all on dealing with the social and cultural problems of populations affected by syphilis.
Topics: Adult; Cohort Studies; Developing Countries; Female; Humans; Infant, Newborn; Penicillin G Benzathine; Penicillins; Pregnancy; Pregnancy Complications, Infectious; Syphilis, Congenital; Time Factors
PubMed: 10210801
DOI: No ID Found -
Antimicrobial Agents and Chemotherapy Sep 1996Broth MICs and time-kill studies were used to test the activity of RP 59500 (quinupristin-dalfopristin), RPR 106972, pyostacine (RP 7293), erythromycin, clarithromycin,... (Comparative Study)
Comparative Study
MIC and time-kill study of antipneumococcal activities of RPR 106972 (a new oral streptogramin), RP 59500 (quinupristin-dalfopristin), pyostacine (RP 7293), penicillin G, cefotaxime, erythromycin, and clarithromycin against 10 penicillin-susceptible and -resistant pneumococci.
Broth MICs and time-kill studies were used to test the activity of RP 59500 (quinupristin-dalfopristin), RPR 106972, pyostacine (RP 7293), erythromycin, clarithromycin, and cefotaxime for four penicillin-susceptible (MICs of 0.008 to 0.03 microgram/ml), two penicillin-intermediate (MIC of 0.25 microgram/ml), and four penicillin-resistant (MIC of 2.0 to 4.0 micrograms/ml) strains of pneumococci: 6 of 10 strains were resistant to macrolides (MICs of > or = 0.5 microgram/ml). MICs of RP 59500 (0.5 to 1.0 microgram/ml), RPR 106972 (0.125 to 0.25 microgram/ml), and pyostacine (0.125 to 0.25 microgram/ml) did not alter with the strain's penicillin or macrolide susceptibility status. Three penicillin-susceptible strains and one penicillin-intermediate strain were susceptible to macrolides (MICs of < or = 0.25 microgram/ml); the macrolide MICs for the remaining strains were > or = 4.0 micrograms/ml. Cefotaxime MICs rose with those of penicillin G, but all strains were inhibited at MICs of < or = 2.0 micrograms/ml. RP 59500 was bactericidal for all strains after 24 h at 2 x MIC and yielded 90% killing of all strains at 6 h at 2 x MIC; at 8 x MIC, RP 59500 showed 90% killing of six strains within 10 min (approximately 0.2 h). In comparison, RPR 106972 was bactericidal for 9 of 10 strains at 2 x MIC after 24 h and yielded 90% killing of all strains at 2 x MIC after 6 h; 90% killing of six strains was found at 8 x MIC at 0.2 h. Results for pyostacine were similar to those of RPR 106972. Erythromycin and clarithromycin were bactericidal for three of four macrolide-susceptible strains after 24 h at 4 x MIC. Clarithromycin yielded 90% killing of three strains at 8 x MIC after 12 h. Cefotaxime was bactericidal for all strains after 24 h at 4 x MIC, yielding 90% killing of all strains after 6 h at 4 x MIC. All three streptogramins yielded rapid killing of penicillin- and erythromycin-susceptible and -resistant pneumococci and were the only compounds which killed significant numbers of strains at 0.2 h.
Topics: Anti-Bacterial Agents; Cefotaxime; Cephalosporins; Clarithromycin; Erythromycin; Microbial Sensitivity Tests; Penicillin G; Penicillin Resistance; Penicillins; Streptococcus pneumoniae; Time Factors; Virginiamycin
PubMed: 8878583
DOI: 10.1128/AAC.40.9.2071 -
Proceedings of the Royal Society of... Nov 1965DOUBLE CHEMOTHERAPY FOR THE TREATMENT OF BACTERIAL INFECTIONS HAS BEEN RECOMMENDED FOR MANY REASONS, OF WHICH THE MOST IMPORTANT ARE THE FOLLOWING: (1) To achieve a...
DOUBLE CHEMOTHERAPY FOR THE TREATMENT OF BACTERIAL INFECTIONS HAS BEEN RECOMMENDED FOR MANY REASONS, OF WHICH THE MOST IMPORTANT ARE THE FOLLOWING: (1) To achieve a synergic effect. (2) To delay the emergence of resistant strains. (3) To prevent superinfection. (4) To treat relatively inaccessible bacteria. (5) To treat mixed infections. (6) To treat undiagnosed infections.Combinations which have a truly synergic effect in vivo are those which show bactericidal synergy in vitro. Bactericidal therapy is of great practical importance in conditions which are inaccessible to the natural defences of the body, or where they are deficient. If in such cases the infecting bacterium is not readily killed by a single drug, then combinations should be tried. There are no absolute rules and double bactericidal sensitivity tests should always be carried out on the infecting strain, but the most likely combination to show this type of synergy is a penicillin and streptomycin.If a bactericidal drug is combined with an agent which is only bacteristatic, the killing effect may be antagonized, since many bactericidal drugs only kill rapidly multiplying cells. Again there are no absolute rules, but antagonism is particularly liable to occur when the bactericidal agent is one of the penicillins and is very unlikely to occur when it is a polymyxin, since this kills resting bacteria.Drug combinations to delay the emergence of drug-resistant strains should be considered for infections due to staphylococci and coliform bacilli, particularly in hospitals, and when it is desired to use drugs to which these bacteria readily develop resistance.Drug combinations may also be the most efficient treatment for mixed infections and may be necessary for the treatment of fulminating infections pending bacteriological diagnosis. The combination of nystatin with a tetracycline may be necessary to prevent candidiasis if tetracycline therapy has to be prolonged.
Topics: Anti-Bacterial Agents; Cross Infection; Drug Synergism; Humans; Penicillin G; Penicillin Resistance; Penicillins; Polymyxins
PubMed: 4285323
DOI: No ID Found -
Antimicrobial Agents and Chemotherapy Jul 1980The penicilllin-binding proteins (PBPs) of several gram-positive and gram-negative bacteria have been examined. The results indicate that: (i) PBPs are membrane proteins...
The penicilllin-binding proteins (PBPs) of several gram-positive and gram-negative bacteria have been examined. The results indicate that: (i) PBPs are membrane proteins with molecular weights ranging from 40,000 to 120,000. When extracted with Triton X-100 from sonicated cells, they appear to fall into two patterns: one found in rods and the other in spheres. A major difference is in the low-molecular-weight component, which is usually the major PBP in bacilli but a minor one in cocci. (ii) There is a wide variation in both the number and the amount of PBPs in different bacteria, and taxonomically related bacteria tend to have similar PBP patterns. These patterns often correlate with the affinity of PBPs for penicillin and other beta-lactam antibiotics. (iii) The low-molecular-weight component usually releases penicillin spontaneously with a half-life of 10 min or less. Most, but not all, PBPs release bound penicillin in the presence of neutral hydroxylamine (0.2 to 0.8 M).
Topics: Amdinocillin; Bacteria; Bacterial Proteins; Carrier Proteins; Cephalothin; Hexosyltransferases; Molecular Weight; Muramoylpentapeptide Carboxypeptidase; Penicillin G; Penicillin-Binding Proteins; Penicillins; Peptidyl Transferases
PubMed: 7416741
DOI: 10.1128/AAC.18.1.148 -
The British Journal of Venereal Diseases Dec 1980In a comparative kinetic study of the serum concentrations of two penicillin complexes--medium-long-acting (benethamine penicillin) and long-acting (benzathine... (Comparative Study)
Comparative Study
In a comparative kinetic study of the serum concentrations of two penicillin complexes--medium-long-acting (benethamine penicillin) and long-acting (benzathine bipenicillin)--after a single injection in young adults and elderly people, the following results were confirmed statistically: (a) age was a major factor in the variations in serum penicillin concentrations and in their persistence in the serum; (b) the penicillin was absorbed faster in young than in elderly subjects even when a long-acting complex was used; (c) serum concentrations below the level regarded as lethal for treponemes appeared much earlier and more frequently in young than in old people; and (d) the bioequivalence between penicillin preparations could not be estimated solely for the number of units of the agent used but from the bioavailability of the chosen formulation. Thus a uniform and standard penicillin dosage allowing no safety margin may help in the superficial healing of a syphilitic chancre or the resolution of a roseola but it will certainly be insufficient to kill Treponema pallidum. It seems essential therefore to provide an antibiotic cover at high dosage over a long period of time.
Topics: Adult; Age Factors; Aged; Biological Availability; Drug Administration Schedule; Female; Humans; Kinetics; Male; Middle Aged; Penicillin G; Penicillin G Benzathine; Penicillins; Syphilis
PubMed: 7448577
DOI: 10.1136/sti.56.6.355 -
The Journal of Antibiotics Oct 1977The preparation of 6-epi-ampicillin by hydrolysis of 6-epihetacillin is described. During this conversion, the formation of a diketopiperazine was also observed. The...
The preparation of 6-epi-ampicillin by hydrolysis of 6-epihetacillin is described. During this conversion, the formation of a diketopiperazine was also observed. The best yield was obtained at pH 7.0 and room temperature for 3 approximately 7 hours. The lowest yield of 6-epi-ampicillin and the highest formation of the diketopiperazine occurred in pyridine - acetic acid - water. Treatment of ampicillin (with D-aminophenylacetyl side chain) with nitrous acid gave alpha-hydroxybenzylpenicillin with about 66% of L- and 34% mandelyl side chain. Reaction 6-epi-ampicillin gave 6-epi-alpha-hydroxybenzylpenicillin with practically the same ratio of L- and D-isomers.
Topics: Ampicillin; Methods; Penicillin G; Stereoisomerism
PubMed: 563392
DOI: 10.7164/antibiotics.30.847 -
The British Journal of Venereal Diseases Oct 1973
Comparative Study
Topics: Ampicillin; Costs and Cost Analysis; Gonorrhea; Humans; Male; Penicillin G Procaine; Penicillins; Probenecid; Uganda
PubMed: 4748409
DOI: 10.1136/sti.49.5.460 -
Journal of Chromatography. A Nov 2021The presence of antibiotics in the aquatic environment is becoming one of the main research focus of scientists and policy makers. Proof of that is the inclusion of four...
The presence of antibiotics in the aquatic environment is becoming one of the main research focus of scientists and policy makers. Proof of that is the inclusion of four antibiotics, amongst which is amoxicillin, in the EU Watch List (WL) (Decision 2020/1161/EU)) of substances for water monitoring. The accurate quantification of amoxicillin in water at the sub-ppb levels required by the WL is troublesome due to its physicochemical properties. In this work, the analytical challenges related to the determination of amoxicillin, and six related penicillins (ampicillin, cloxacillin, dicloxacillin, penicillin G, penicillin V and oxacillin), have been carefully addressed, including sample treatment, sample stability, chromatographic analysis and mass spectrometric detection by triple quadrupole. Given the low recoveries obtained using different solid-phase extraction cartridges, we applied the direct injection of water samples using a reversed-phase chromatographic column that allowed working with 100% aqueous mobile phase. Matrix effects were evaluated and corrected using the isotopically labelled internal standard or correction factors based on signal suppression observed in the analysis of spiked samples. The methodology developed was satisfactorily validated at 50 and 500 ng L for the seven penicillins studied, and it was applied to different types of water matrices, revealing the presence of ampicillin in one surface water sample and cloxacillin in three effluent wastewater samples.
Topics: Amoxicillin; Ampicillin; Chromatography, High Pressure Liquid; European Union; Penicillins; Solid Phase Extraction; Water
PubMed: 34662823
DOI: 10.1016/j.chroma.2021.462605 -
Antimicrobial Agents and Chemotherapy Apr 1997In this report, we present MIC, bactericidal activity, postantibiotic effect (PAE), and in vivo infectivity data for postantibiotic-phase pneumococci. We compared and... (Comparative Study)
Comparative Study
Comparative study of bactericidal activities, postantibiotic effects, and effects of bacterial virulence of penicillin G and six macrolides against Streptococcus pneumoniae.
In this report, we present MIC, bactericidal activity, postantibiotic effect (PAE), and in vivo infectivity data for postantibiotic-phase pneumococci. We compared and evaluated penicillin G and six macrolides, erythromycin, azithromycin, clarithromycin, dirithromycin, roxithromycin, and spiramycin, against 10 strains of pneumococci with various levels of susceptibility to penicillin. All of the agents, except azithromycin, exhibited a bactericidal effect (a > or = 3 log10 decrease in the number of CFU per milliliter) after 4 h of exposure to a concentration equal to 10 times the MIC, displaying the following hierarchy: spiramycin = penicillin G = erythromycin = dirithromycin = clarithromycin = roxithromycin > azithromycin. The bactericidal rate of penicillin G was significantly lower for resistant strains (MIC, > or = 2 microg/ml), while bactericidal rates of macrolides were unaffected by penicillin susceptibility. A PAE was induced in all of the strains by all of the antibiotics after exposure for 1 h to a concentration equivalent to 10 times the MIC. The mean duration of PAEs varied between 2.3 and 3.9 h, showing the following hierarchy: spiramycin = dirithromycin = clarithromycin = erythromycin = roxithromycin > azithromycin > penicillin G. Virulence studies were performed with immunocompetent mice by intraperitoneal inoculation of virulent, penicillin-susceptible serotype 3 pneumococci which had been pre-exposed to penicillin G or a macrolide for 1 h. A significant decrease in the virulence of postantibiotic-phase pneumococci was induced only by erythromycin, azithromycin, dirithromycin, and spiramycin, displaying 5.9-, 7.1-, 4.2-, and 3.6-fold increases in the 50% lethal dose (LD50) compared to a control suspension, respectively. No significant correlation could be demonstrated between the LD50 and the MIC, bactericidal activity, or PAE duration. These results suggest that antimicrobial interaction with host defenses in terms of virulence might be a significant parameter that could influence the drug or drug regimen of choice.
Topics: Animals; Anti-Bacterial Agents; Culture Media; Female; Macrolides; Mice; Microbial Sensitivity Tests; Penicillin G; Penicillin Resistance; Penicillins; Pneumococcal Infections; Regression Analysis; Streptococcus pneumoniae; Time Factors
PubMed: 9087489
DOI: 10.1128/AAC.41.4.781