The pharmacokinetic properties of cefodizime, a new aminothiazolyliminomethoxycephalosporin, were studied in laboratory animals and compared with the pharmacokinetics of another long-acting cephalosporin, ceftriaxone. Both cephalosporin derivatives showed high affinity (33-.99%) for serum proteins. High and prolonged blood respectively serum levels of the antibiotics were achieved following subcutaneous and intravenous injection into mice, rats, rabbits, dogs and monkeys. Cefodizime elimination half-lives ranged from 1.17 hours in mice to 3.53 hours in rabbits compared to ceftriaxone half-lives ranging from 0.73 hour in mice to 7.31 hours in rabbits. The antibiotics were well distributed in the body and penetrated into tissues and body fluids to a high degree. Particularly high and prolonged levels were detected in the lungs, liver and kidneys of the experimental animals. Large amounts, approximately 35-55% of the given dose, were recovered in the urine of rabbits and dogs, while the recovery rate in the bile of rabbits was only 0.57% for cefodizime and 1.08% for ceftriaxone.
AIMS To determine the eventual advantage of the new 1997 TNM as prognosis predictor for gastric cancer patients submitted to an R0 resection and to compare it with two other lymph-node involvement classifications, the 1990 TNM and the Okusa system. METHODS From January 1980 to December 1995, an R0 resection was performed as primary therapy in 275 cases of gastric cancer. These operations consisted of a total or sub-total gastrectomy and of a D2 type lymph-node dissection. Tumour classification was performed according to 1990 and 1997 TNM systems, and to the Okusa lymph node classification. The statistical methods used to evaluate prognostic value were: Kaplan-Meier survival estimates; the log-rank test for univariate analysis; and Cox's model for multivariate analysis. RESULTS The 1990 TNM showed the best stratification power in univariate analysis. In multivariate analysis, the Okusa classification was identified as the best prognostic index (P<0.01). The 1997 TNM showed worse stratification capability than the two other systems. CONCLUSIONS In the present series, the new TNM (1997) did not improve the prognostic stratification of lymph-node involvement. An adequate and universal system for lymph-node stratification is necessary and further validation of these classifications is needed.
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Ofloxacin, its optical isomers levofloxacin (HR 355, DR-3355) and D-ofloxacin (DR-3354) and ciprofloxacin were administered orally to mice and rats which had systemic and localized infections. Both levofloxacin and ciprofloxacin were equally effective in treating systemic murine infections caused by staphylococci, Enterobacteriaceae or Pseudomonas aeruginosa with ED(50)s ranging from 0.18 to 15.8 mg/kg and 0.42 to 16.3 mg/kg respectively and both these agents were twice as effective as ofloxacin which had an ED(50) 0.41 to 39.7 mg/kg. In contrast, D-ofloxacin was either inactive or exhibited only modest chemotherapeutic activity against the staphylococci and the Gram-negative organisms tested.When given to mice to treat staphylococcal abscesses and lung infections due to Klebsiella pneumoniae DT-S levofloxacin was up to four times more effective and produced a more pronounced bactericidal effect against the pathogens in vitro than the reference compounds.Despite possessing a similar, if not lesser, in-vitro activity against the infecting pathogens, levofloxacin was more effective than ofloxacin and ciprofloxacin in rats with localized infections caused by Enterobacteriaceae and P. aeruginosa.
Methods for the removal and the oxidation of the lipid moiety of the antibiotic moenomycin A have been studied. Combined with biochemical studies,the results demonstrate that antibiotic activity is closely related with the integrity of the lipid unit.
A new glycopeptide antibiotic, balhimycin, has been isolated from the fermentation broth of a Amycolatopsis sp. Y-86, 21022. Balhimycin belongs to the vancomycin class of glycopeptides and contains a dehydrovancosamine sugar. The biological activity of balhimycin has been compared extensively with that of vancomycin against methicillin resistant staphylococci and also against anaerobes. Balhimycin is marginally superior to vancomycin in its in vitro activity against anaerobes and in its bactericidal properties.
COMPOUND PRESENTED 31668P 31668U and a compound of the following formulas. ACTION HAS ANTIBIOTIC COMPOUNDS AND ANTITUMOR.
Moenomycin A was degraded by enzymatic cleavage of the bond between the moenuronic acid moiety and the phosphate group. The phosphoric acid monoester 4a could be dephosphorylated further to yield 3a. Compound 3a was used to confirm the previous configurational assignment at C-2 of the glycerate part of moenomycin A and to prepare ent-4a. 4a and ent-4a are antibiotically inactive.
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Isolation, structural assignment, and antibiotic efficiency of the new moenomycin antibiotics C3 (1b) and C4 (1c) is decribed. The previously published structure of pholipomycin (1d) is modified.
The aminothiazolyl-cephalosporin RU 29 246 is the active metabolite of the prodrug pivaloyloxyethylester HR 916. RU 29 246 in vitro activity includes a wide range of clinically relevant bacterial pathogens. Against methicillin-sensitive Staphylococci RU 29 246 (MIC90 of 0.25 approximately 2-mu-g/ml) was clearly more active than cefaclor, cefuroxime, cefpodoxime, cefixime and ceftibuten, but slightly less active than cefdinir. RU 29 246 inhibited hemolytic Streptococci of the serogroups A, B, C and G as well as penicillin-sensitive Streptococcus pneumoniae at concentrations similar to cefdinir, cefpodoxime and cefuroxime (MIC90 less-than-or-equal-to 0.13-mu-g/ml), but less than the other oral cephaiospofins investigated (cefixime, cefaclor and ceftibuten). MIC90s of RU 29 246 against Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Salmonella spp., Shigella spp., Proteus mirabilis and Haemophilus influenzae were less-than-or-equal-to 0.5-mu-g/ml. Only RU 29 246 and cefdinir demonstrated moderate activity against Acinetobacter baumannii (MIC90 greater-than-or-equal-to 4-mu-g/ml). Most strains of Pseudomonas spp., Serratia marcescens, Enterobacter spp., Hafnia alvei and Bacteroides spp. were resistant to RU 29 246. RU 29 246 killed Escherichia coli and Staphylococcus aureus at a rate of 99% to 99.9% at concentrations of two times MIC. The pH value of the medium (range 5.5 to 8.5) and the inoculum size (range 10(5) to 10(7) cfu/ml) had no or only low influence on the antibacterial activity of RU 29 246. RU 29 246 is a broad spectrum cephalosporin including in its activity both Gram-positive and Gram-negative pathogens and therefore-depending on the bioavailability of its prodrug-looks promising as to its therapeutic perspective.
Cefodizime was evaluated for its effect on a number of parameters of leukocyte function in humans. Four healthy volunteers received 2 g i.v. b. i. d. for seven days. Leukocyte activity was measured before, during and after treatment. Using opsonized zymosan as a stimulant, no effect on the respiratory burst of granulocytes was observed. It was found, however, that the lymphocytes in three of the four subjects showed significantly more marked proliferation rates in the mixed lymphocyte reaction after administration of cefodizime than at baseline. The stimulation indices subsequently returned to normal. This pilot study therefore demonstrated that cefodizime has biological response modifying properties in healthy humans.
The aminothiazolyl-cephalosporin RU 29 246, the active metabolite of the prodrug-ester HR 916, is active against strains producing the widespread plasmid-encoded TEM-1, TEM-2 and SHV-1 beta-lactamases. Except for TEM-7 the activity of RU 29 246 against strains producing extended broad spectrum beta-lactamases (TEM-3, TEM-5, TEM-6, SHV-2, SHV-4, SHV-5, CMY-1, CTX-M), however, is low. Relative hydrolysis rates of RU 29 246 are comparable with those of cefpodoxime, the active metabolite of CS-807, and are extremely low for the TEM-1 and SHV-1 beta-lactamases. The compound demonstrates remarkable inhibitory activity against the chromosomal beta-lactamase of Enterobacter cloacae P99. In the presence of 1.7 microM this enzyme loses 50% of its activity. At concentrations of 0.43, 0.003 and 0.01 micrograms/ml the compound binds preferentially to the penicillin-binding protein (PBP) 3 of Escherichia coli K12, to the PBPs 2x and 3 of Streptococcus pneumoniae R6 and to PBP 1 of Staphylococcus aureus SG 511, respectively.
Cefpirome, cefoperazone and ceftazidime were tested for their in-vitro activity against Enterococcus faecalis and methicillin-resistant Staphylococcus aureus (MRSA) isolates. Cefpirome was the most active cephalosporin followed by cefoperazone. Ceftazidime had only very limited activity against these strains. In experiments with cefpirome/vancomycin and cefoperazone/vancomycin combinations, synergy was detected against most MRSA strains and some enterococci. Antagonism did not occur.
The pharmacokinetic profile of cefpirome was evaluated in rats and dogs after a single intravenous or intramuscular dose. A two-compartment open model was used for the calculation of the pharmacokinetic parameters for both routes of administration. The elimination half-lives after intravenous and intramuscular administration of 20 mg/kg cefpirome did not differ significantly and ranged from 0.4 h in rats to 1.1 h in dogs. Cefpirome was mainly excreted via the kidneys. After iv or im dosing of the compound, between 80% (dogs) and 90% (rats) was recovered in urine within 24 h. The bioavailability of cefpirome in rats and dogs after both routes of administration was almost identical when calculated either by the AUC or the urinary recovery rates.