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PubMed1987

Comparative in vitro activity of the two new oral cephalosporin metabolites RO 19-5247 and RO 15-8074.

A total of 629 clinical strains of gram positive and gram negative bacteria were tested for their susceptibility to RO 19-5247, RO 15-8074, and other antimicrobial agents. Both RO 19-5247 and RO 15-8074 had good activity against strains of Enterobacteriaceae; however, resistance was found among some strains of Enterobacter, Citrobacter, Klebsiella and Morganella spp. Both compounds showed moderate to poor active against Acinetobacter spp., Pseudomonas aeruginosa, staphylococci and Streptococcus faecalis. Against strains of Haemophilus influenzae, Neisseria gonorrhoeae, Gardnerella vaginalis, Streptococcus pneumoniae and streptococci (not enterococci), each compound was highly active in vitro. RO 19-5247 and RO 15-8074 had comparable activity to cotrimoxazole, ceftazidime and ceftizoxime. Each new compound had considerably better activity then did cefaclor and amoxicillin/potassium clavulanate.

Cefmenoxime↗

PubMed1983

In vitro activity of HR 810, a new broad-spectrum cephalosporin.

HR 810, 3-[(2,3-cyclopenteno-1-pyridinium)methyl]-7-[2-syn-methoximino-2-(2-aminothiazole-4-yl)-acetamido] ceph-3-em-4-carboxylate, is a new semisynthetic cephalosporin derivative. The in vitro activity of HR 810 was compared with that of cefotaxime, ceftazidime, piperacillin and gentamicin using 368 strains of gram-negative and gram-positive bacteria. HR 810 was highly active against Enterobacteriaceae, being the most active of the cephalosporins against Enterobacter, Serratia and Citrobacter spp.; the MICs ranged from much less than 0.06 to 8 mg/l. The activity of HR 810 against Pseudomonas aeruginosa and Acinetobacter spp. was almost as good as that of ceftazidime. The new compound was superior to the other cephalosporins against Staphylococcus aureus and inhibited all Streptococcus faecalis strains at a concentration of 16 mg/l.

Cefotaxime↗

PubMed1982

Comparative synergistic activity of netilmicin-piperacillin versus gentamicin-piperacillin.

The synergistic action of the combination netilmicin-piperacillin in comparison to gentamicin-piperacillin was studied in 206 clinical isolates of staphylococci, enterococci, Enterobacteriaceae and Pseudomonas aeruginosa by means of the checkerboard technique. Overall, netilmicin-piperacillin acted synergistically against 31% and gentamicin-piperacillin against 14% of the 206 strains. In particular, synergism was more frequently observed with netilmicin-piperacillin against Escherichia coli, Citrobacter spp., indole-positive Proteus spp. and Pseudomonas aeruginosa. Synergy was uncommon with either combination against enterococci, Staphylococcus epidermidis and Serratia spp. Only partial synergy or indifference was seen with both combinations against Klebsiella spp. The interaction of netilmicin would appear to be superior to that of gentamicin in combination with piperacillin.

Bacteria↗

PubMed1983

Norfloxacin versus cotrimoxazole in the treatment of lower urinary tract infections.

In a randomised prospective study 61 patients with lower urinary tract infection received either 200 mg norfloxacin (33 patients) or 480 mg cotrimoxazole (28 patients) twice daily for ten days. Pathogens included Escherichia coli in 48 patients, Proteus mirabilis in ten patients, and Enterobacter cloacae, Klebsiella pneumoniae, Citrobacter freundii and Staphylococcus saprophyticus in one patient each. The MICs of norfloxacin and cotrimoxazole were less than or equal to 0.03 mg/l and less than or equal to 1 mg/l respectively. On the tenth day of treatment 94% of the patients receiving norfloxacin and 89% of the patients receiving cotrimoxazole were clinically cured, and the pathogens were eradicated in 94% and 96% of the patients respectively. At six week follow-up one patient given cotrimoxazole and two given norfloxacin had a reinfection. No side-effects or toxicity were observed with the exception of a diffuse rash in one patient receiving cotrimoxazole in whom treatment was discontinued. It is concluded that norfloxacin is safe and as effective as cotrimoxazole in the treatment of lower UTI and should have an important role to play whenever multiresistant organisms are implicated.

Adult↗

PubMed1979

Identification of Bacteroides fragilis by indirect immunofluorescence.

Rabbit antiserum against live or heat-killed Bacteroides fragilis NCTC 9343 bacteria was titrated against hot phenol water-extracted polysaccharide antigens from five different species of the 'B. fragilis group' of bacteria using an enzyme immunoassay and shown to be specific for the B. fragilis NCTC 9343 polysaccharide. When the antiserum was used in indirect immunofluorescence, 97.1% of 244 B. fragilis strains were correctly identified. Only 8 of the other 312 Bacteroides strains were stained by the anti-B fragilis serum. The 'cross-reactive' Bacteriodes strains all belonged to the "B. fragilis group" of bacteria (i.e., B; distasonis, B. ovatus, B. thetaiotaomicron, B. uniformis, and B. vulgatus). None of the 425 aerobic enteric bacteria representing Salmonella, E. coli, Proteus, Yersinia, Shigella, Klebsiella, Enterobacter, Citrobacter, and Pseudomonas were positive using the anti-B. fragilis serum. Likewise, all the 59 gram-positive strains representing Streptococcus, Bacillus, Peptostreptococcus, Peptococcus, Propionibacterium, Lactobacillus, Eubacterium, and Clostridium did not stain. Our data shows in accordance with other findings [11], that B. fragilis strains possess a species-specific cell envelope antigen(s) which promises to be important for production of antisera, making a rapid identification of the species possible.

Bacteria↗

PubMed1975

Four hour-test for the identification of Enterobacteriaceae.

A set of 12 rapid biochemical tests--lysinedecarboxylase, ornithinedecarboxylase, beta-galactosidase, urease, hydrogensulphide, indole, acetoin, deoxyribonuclease, esculin, mannitol, raffinose and sorbitol--were selected from an original set of 13 tests and were found to give 98% accurate reactions within 4 hrs of incubation for the identification of bacteria belonging to Enterobacteriaceae. This set permits identification on the genus and/or species level for Escherichia, Shigella, Citrobacter, Salmonella, Klebsiella, Enterobacter, Serratia and Proteus.

Acetoin↗

PubMed1984

Growth of clinical isolates in the cold.

Common clinical isolates were tested to determine their ability to multiply after 7 days at 4 degrees C in trypticase soy broth. 34% of the 214 isolates grew in the cold. Citrobacter freundii, Group D Enterococci, Klebsiella oxytoca, Proteus vulgaris, Providencia rettgeri and Serratia marcescens grew best of all. The importance of growth in the cold is discussed.

Bacteria↗

PubMed1977

Synthetic disaccharide-protein antigens for production of specific 04 and 09 antisera for immunofluorescence diagnosis of salmonella.

The synthetic disaccharides abequose 1 leads to a 3 mannose and tyvelose 1 leads to a 3 mannose, representative of Salmonella O-antigen 4 and 9 respectively, were covalently linked to bovine serum albumin (BSA) . Antisera from rabbits immunized with these immunogens were used in indirect immunofluorescence assay for the identification of group B (O-antigen 4) and D (O-antigen 9) Salmonella. A total of 1030 enteric bacterial strains were tested, including 207 group B and 55 group D Salmonella. The anti-abequose-mannose-BSA serum correctly identified all Salmonella group B strains tested. The anti-tyvelose-mannose-BSA serum correctly indentified all Salmonella group D bacteria examined with the exception of 11 of 18 Vi-positive S. typhi strains which did not not stain until the Vi-antigen was removed by boiling. Among the 768 strains representing Salmonella other than groups B and D, E. coli, Shigella, Citrobacter, Klebsiella, Enterobacter, Serratia, Proteus, Vibrio, Pseudomonas, Aeromonas, Yersinia, Bacteroides and Fusobacterium only 5 positive reactions were found. These were observed with Y. pseudotuberculosis strains which have the same disaccharide antigenic determinants as Salmonella O-antigen 4 and 9 respectively. The high specificity of the antisera elicited by the synthetic disaccharide-BSA immunogens make them suitable for a specific and rapid identification of Salmonella bacteria belonging to serogroups B and D.

Animals↗

PubMed1995

Multicentre comparative study on the antibacterial activity of FK-037, a new parenteral cephalosporin.

The in vitro antibacterial activity of FK-037, a new parenteral cephalosporin structurally related to cefpirome and cefepime, was compared with that of cefotaxime, ceftazidime, aztreonam, cefpirome, cefepime, imipenem and meropenem against 1,837 clinical isolates obtained from three Spanish hospitals. FK-037 inhibited 90% of Enterobacteriaceae isolates at < or = 0.25 microgram/ml, with the exception of Enterobacter aerogenes (MIC90 1 microgram/ml), Enterobacter cloacae and Citrobacter freundii (MIC90 8 micrograms/ml). In cefotaxime- and ceftazidime-resistant Klebsiella pneumoniae strains producing SHV-2 and SHV-6 beta-lactamases, the activity of FK-037, cefpirome and cefepime was similar (MIC range 0.25-32 micrograms/ml). In Enterobacteriaceae strains hyper-producing chromosomally inducible beta-lactamases, FK-037 (MIC90 range, 0.25-8 micrograms/ml) was 8- to 16-fold more active than cefotaxime and ceftazidime but two- to eightfold less active than cefpirome and cefepime. FK-037 and cefpirome were twofold more active than ceftazidime and cefepime against Pseudomonas aeruginosa isolates, with MIC90 values of 16 micrograms/ml. The activity of FK-037, cefpirome and cefepime was two- to eightfold lower in ceftazidime-resistant derepressed Pseudomonas aeruginosa mutants. FK-037 (MIC range, 0.12-2 micrograms/ml) and the other beta-lactam agents tested were active against methicillin-susceptible staphylococci; however, only cefpirome and, particularly, FK-037 (MIC90 of 32 micrograms/ml) displayed some activity against methicillin-resistant strains. In penicillin-susceptible, -intermediate and -resistant Streptococcus pneumoniae isolates, the MIC90s of FK-037 were 0.03, 0.5 and 1 microgram/ml, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Aztreonam↗

PubMed1984

Recognition and clinical significance of mechanisms of bacterial resistance to beta-lactams.

Resistance to beta-lactams may be difficult to recognize. This is due to the difficulty in detecting these resistances, when the routine tests performed in diagnostic laboratories are interpreted in the usual manner. Since failure to recognize this type of resistance may have serious consequences for the patient, it is essential that it be detected when present. For the detection of methicillin resistance of Staphylococcus aureus a standardized method using either a medium containing 5% NaCl or a low incubation temperature is advocated. Methicillin resistance of S. epidermidis can only be recognized reliably by means of a quantitative test and incubation for 42-48 h. Resistance of Haemophilus influenzae to ampicillin may be intrinsic or it may be caused by a TEM beta-lactamase; a beta-lactamase test should be used to detect the latter type of resistance. Inducible cephalosporinase may be responsible for the rapid development of resistance of some bacterial species to cefamandole, even during therapy. If a stable beta-lactamase production is attained by mutation, resistance to other beta-lactams will usually be present as well. Routine induction tests should be performed for all isolates of species of Enterobacter, Serratia, Citrobacter and Proteus, indole-positive. The same type of 'hidden' resistance may be present in Pseudomonas aeruginosa, with regard to cefotaxime and other third-generation cephalosporins. Beta-lactamase-positive Neisseria gonorrhoeae can easily be recognized by a beta-lactamase test. In addition, the results of diffusion tests allow one to distinguish between beta-lactamase-positive and beta-lactamase-negative strains. Recognition of those strains of N. gonorrhoeae having a decreased susceptibility to penicillin is only possible when well-standardized quantitative tests are used.

Ampicillin↗

PubMed1994

Genetics of extended-spectrum beta-lactamases.

Bacteria have adapted to the introduction of aztreonam, cefotaxime, ceftazidime, ceftriaxone and other oxyimino-beta-lactams by altering existing plasmid-mediated class A and class D beta-lactamases so as to expand their spectrum of activity. In the TEM and SHV families of extended-spectrum beta-lactamases, relative activity toward oxyimino-substrates increases with the number of amino acid substitutions but at the price of lowered intrinsic efficiency, so that compensatory up-promoter events are often associated with increased enzyme expression. Another new mechanism of resistance is the capture on plasmids of normally chromosomal genes from Enterobacter cloacae, Citrobacter freundii or Pseudomonas aeruginosa, which upon transfer can provide Klebsiella pneumoniae or Escherichia coli with resistance to alpha-methoxy-beta-lactams, such as cefoxitin or cefotetan, as well as to oxyimino-beta-lactams.

Bacteria↗

PubMed1991

The influence of clinical use of antibiotics and the sensitivity of strains isolated from postoperative infections--a comparison of nosocomial pathogens with strains isolated from the bacterial flora of patients.

In the present study, we investigated how the recent clinical use of antibiotics have altered the antibiotic susceptibility of strains isolated from postoperative infections, especially Gram-negative rods. For Pseudomonas aeruginosa, serogroup E strains accounted for about 20 per cent of postoperative infections, but were unable to be isolated from either the feces of patients on admission or from the appendix contents of patients with appendicitis. It therefore appeared that serogroup E strains were responsible for the nosocomial infections in our department. The strains of methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa serogroup E, which we assumed to be nosocomial pathogens, acquired a high level of resistance to antibiotics soon after third-generation cephems became widely used. On the other hand, the antibiotic susceptibility of Enterobacter cloacae, Citrobacter freundii, and the serogroups of Pseudomonas aeruginosa other than E, which were considered to originate from the bacterial flora of patients, did not vary throughout the several years of the study period.

Bacteria↗

PubMedDate not supplied

Resistance to third-generation cephalosporins in adult gram-negative bacillary meningitis.

Ninety-three patients with gram-negative bacillary meningitis (GNBM) were identified at Kaohsiung Chang Gung Memorial Hospital, over a period of 12 years. Among them, eight showed resistance to third-generation cephalosporins, accounting for 9% of the total GNBM cases and 29% of the postneurosurgical GNBM cases. The resistant pathogens included Acinetobacter baumannii, Klebsiella pneumoniae, Citrobacter freundii and Morganella morganii. These eight patients, six males and two females aged 18-61 years, all had nosocomially acquired meningitis associated with head trauma and/or postneurosurgical states. Six patients received imipenem/cilastatin treatment; five survived and one died. The other two expired because they did not receive appropriate antibiotic treatment. Although third-generation cephalosporin-resistant GNBM is rare, its incidence has been increasing over the past 5 years. In patients with nosocomially-acquired postneurosurgical GNBM, the presence of third-generation cephalosporin resistance should therefore be highly suspected. The appropriate choice of antibiotic is essential for their survival.

Adolescent↗

PubMed2001

Occurrence and transferability of beta-lactam resistance in Enterobacteriaceae isolated in Children's University Hospital in Bratislava.

Occurrence and transferability of beta-lactam resistance in 30 multi-resistant Escherichia coli, Klebsiella spp., Enterobacter spp., Pantoea agglomerans, Citrobacter freundii and Serratia marcescens strains isolated from children between 0 and 3 years of age is presented. The strains were resistant to ampicillin (30), cefoxitin (22), cefotaxime (30), ceftriaxone (30), ceftazidime (30) and aztreonam (28), but susceptible to cefepime (30) and imipenem (26). Twenty-eight of 30 isolates possessed a transferable resistance confirmed by conjugation and isolation of 79-89-kb plasmids. The beta-lactam resistance was due to production of beta-lactamases and ceftazidime proved to be stronger beta-lactamase inductor than ceftriaxone. Twenty-five clinical isolates expressed transferable extended spectrum beta-lactamases, and chromosomally encoded AmpC beta-lactamase.

Anti-Bacterial Agents↗

PubMed1997

Degradation of commercial detergent products by microbial populations of the Lagos lagoon.

The biodegradability potentials of three detergent products with the trade names Omo, Teepol and sodium dodecyl sulfate (SDS) by the native bacteria of the Lagos lagoon was carried out using the lagoon die-away method. Physicochemical parameters of the water samples showed that the lagoon in Apapa was more polluted than at the University of Lagos. In 12 days, approximately 30, 60 and 97% of Omo, Teepol and SDS respectively were degraded. SDS with an alkyl sulfate moiety as surfactant supported the highest growth of the detergent-utilizing organisms, indicating that the components of Omo and Teepol are more resistant to microbial attack. The detergent-utilizing bacteria identified were mainly Gram-negative and of the following genera: Vibrio, Klebsiella, Flavobacterium, Pseudomonas, Escherichia, Enterobacter, Proteus, Shigella and Citrobacter. Vibrio was the most frequently encountered organism while Proteus was the rarest. Results of this investigation had shown that detergents made in Nigeria may still contain components that are recalcitrant to biodegradation.

Bacillus↗

PubMed2006

Diverse endophytic bacteria isolated from a leguminous tree Conzattia multiflora grown in Mexico.

Conzattia multiflora is a leguminous tree present only in Mexico and Guatemala. There is no record about its symbiotic or pathogenic microbes. In this study, we found that numerous bacteria with 10(4)-10(6) individuals per gram of fresh epidermis were distributed in the tissue of this plant. All the bacteria isolated from the Conzattia epidermis were Gram-negative, facultative anaerobic rods and formed yellow or colorless colonies. They were identified as endophytes by inoculation tests. Some of the bacteria could significantly promote the growth of Conzattia seedlings. Nine different groups were defined by PCR-based RFLP, which were classified as Pantoea, Erwinia, Salmonella, Enterobacter, Citrobacter and Klebsiella by the phylogenetic analysis of 16S rRNA genes. The existence of plant-borne lineages of Salmonella indicates that the unexplored plants may harbor some unknown microbes.

Acetylene↗

PubMed1997

Sensitivity to pH, product inhibition, and inhibition by NAD+ of 1,3-propanediol dehydrogenase purified from Enterobacter agglomerans CNCM 1210.

Because of its key role in the metabolism of glycerol during fermentation, 1,3-propanediol dehydrogenase (EC 1.1.1.202) of Enterobacter agglomerans CNCM 1210 was purified to homogeneity and studied with respect to its sensitivity to pH and to nucleotide and 1,3-propanediol concentrations. Enzyme activity was optimal at pH 7.8. The enzyme was competitively inhibited by NAD+ (Ki of 0.29 mM), and 1,3-propanediol exerted a strong inhibitory effect according to a mixed-type inhibition with a Ki of 13.7 mM and an a-factor of 9.0. It is proposed that these dehydrogenase properties be extended to the dehydrogenases of Citrobacter freundii and Klebsiella pneumoniae, which exhibited numerous similar physical properties.

Alcohol Dehydrogenase↗

PubMed2001

Further studies on RpoS in enterobacteria: identification of rpoS in Enterobacter cloacae and Kluyvera cryocrescens.

RpoS, the alternative sigma factor sigma(s), is important for bacterial survival under extreme conditions. Many enterobacteria are opportunistic human pathogens and their ability to survive in a changing environment could be an essential step for their virulence. To determine the presence of this gene in enteric bacteria, an Escherichia coli rpoS probe was constructed and used to detect the presence of this gene in different species. A gene homologous to rpoS was found in Citrobacter amalonaticus, Enterobacter cloacae, Klebsiella planticola, Kluyvera cryocrescens, Serratia rubidaea, Shigella sonnei, and Yersinia ruckeri. Providencia stuartii and Proteus vulgaris were the only tested enterobacteria that did not show any signal with the E. coli rpoS probe or that did not lead to amplification of an rpoS fragment using specific primers. The rpoS gene from E. cloacae and from K. cryocrescens was cloned and sequenced and a mutant allele was constructed in E. cloacae. Survival rates under different harsh conditions were followed in order to determine the effect of rpoS inactivation in exponential- and stationary-phase cells of both strains. E. cloacae rpoS mutants were more sensitive to extreme pH, high osmolarity, and high temperature than the wild-type.

Amino Acid Sequence↗