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Biomedical subjects

R Marre

Publications and source records attributed to R Marre.

At least 109 records · Page 6Linked to original sources
PubMed1990

[The diagnostic value of bronchoalveolar lavage in opportunistic pneumonia following kidney transplantation].

In 18 renal transplant patients with pneumonia under ciclosporin therapy the diagnostic value of BAL and of covered micro brush smears were compared. In 10 out of 18 cases partly atypical bacterial pathogens were cultivated and cytomegaly was diagnosed 4 times, mycosis twice, whereas 2 cases could not be clarified. A granulocytosis in the differential cell pattern correlated with a bacterial infection.

Bronchoalveolar Lavage Fluid↗
PubMed1989

The cell-bound hemolysin of Serratia marcescens contributes to uropathogenicity.

The contribution of the cell-bound hemolysin of Serratia marcescens to uropathogenicity was studied in an experimental urinary tract infection in rats. The strain carrying the Serratia hemolysin colonized the urinary tract more and lead to a stronger inflammatory response compared to the isogenic hemolysin negative strain.

Animals↗
PubMed1989

Oral vaccination of rats with live avirulent Salmonella derivatives expressing adhesive fimbrial antigens of uropathogenic Escherichia coli.

The avirulent Salmonella typhimurium F885 was transformed with a plasmid carrying the cloned S fimbriae genes of a uropathogenic Escherichia coli. The resulting transformant (F885-1) produced efficiently E. coli S fimbriae and was used for live oral vaccination of rats. For comparison rats were immunized subcutaneously with isolated S fimbriae. Both routes of vaccination resulted in a significant IgG antibody response to S fimbriae. In addition live oral vaccination induced a serum IgA response against S fimbriae. After transurethral infection of rats with a S fimbriae producing E. coli a 10-fold reduction of bacterial counts in the kidney was observed in rats orally vaccinated with F885-1 as compared to unvaccinated controls. This study suggests that the avirulent Salmonella F885 may be used as a fimbrial antigen carrier for oral vaccination against renal infections.

Adhesins, Escherichia coli↗
PubMed1989

Staphylococcus saprophyticus urease: characterization and contribution to uropathogenicity in unobstructed urinary tract infection of rats.

We studied the biochemical properties of the urease of Staphylococcus saprophyticus and the possible role of the urease in experimental urinary tract infections. For this purpose, the nonhemagglutinating and nonadherent strain 9325, which was isolated from a case of symptomatic urinary tract infection, was used. The urease was shown to have a Km of 6.64 mM urea and a Vmax of 4.59 mumol NH3.min-1.mg-1. The enzyme was inhibited by acetohydroxamic acid in a noncompetitive manner. By means of Sephacryl S-300 column chromatography, we determined a mean molecular weight (+/- standard error of the mean) of 420,000 +/- 16,000. To assess the contribution of S. saprophyticus urease to uropathogenicity, a urease-negative mutant was constructed by nitrosoguanidine mutagenesis. In the rat model of ascending unobstructed urinary tract infection, higher numbers of CFU.gram of tissue-1 and more-severe lesions were detected with the parent strain. Moreover, bladder stones were found in animals infected with the urease-positive strain only. Interestingly, the difference in mean bacterial counts of the bladders was found to be significant by the Wilcoxon two-sample test (P less than 0.05), whereas that between the kidney bacterial counts was not. Immunoblot studies revealed a faint antibody response in rats infected with the mutant strain, although bacteria could still be detected in the kidneys after 7 days. Sera of animals challenged with the parent strain reacted strongly with many antigens of S. saprophyticus. Our data indicate that urease is a major factor for invasiveness of S. saprophyticus, especially in the tissue of the bladder, whereas persistence in the urinary tract and nephropathogenicity of this organism are governed by factors other than urease.

Animals↗
PubMed1989

Cloning and expression of Staphylococcus saprophyticus urease gene sequences in Staphylococcus carnosus and contribution of the enzyme to virulence.

The urease gene of Staphylococcus saprophyticus CCM883 was cloned and expressed in Staphylococcus carnosus TM300. In vitro translation of the cloned DNA sequences revealed six polypeptides (of 70, 47, 29, 27, 20, and 17 kilodaltons) that were associated with enzyme activity. Introduction of the cloned genes into a urease-negative mutant of S. saprophyticus restored the virulence of this strain, confirming our previous suggestion (S. Gatermann, J. John, and R. Marre, Infect. Immun. 57:110-116, 1989) that this enzyme is a major virulence factor of the organism and contributes mainly to cystopathogenicity.

Animals↗
PubMed1988

[Etiology of pathogen-induced changes between the toes in patients working under moist conditions].

Referring to recent studies, we discuss the epidemiology of tinea pedis and its position within the range of polyetiological foot infections caused by microbial agents. 201 industrial workers used to wear rubber boots because of moist working conditions were examined with regard to their feet. 107 of them showed clinically altered toe web; in 45 cases, we found ringworm infection (22.4%), in correlation to increased daily wearing time of rubber boots. 85 workers showed colonization of pathogenic bacteria (42.4%), especially gram-negative species (25.8%). Frequently, mixed infections were found. The clinical picture not always allows definite conclusions as to the causal agents. The symptom "maceration" is seen in each of the 3 pathogenic groups of germs (fungi, gram-positive pathogenic cocci, gram-negative bacteria), frequently in bacterial foot infections, especially gram-negative infections. Marked clinical symptoms involve increased infection rates. The predisposing factors to foot infection such as interdigital maceration and the promoting role of rubber boots have been confirmed. The final diagnosis is to be reassured by cultural investigations, in order to set up a specific treatment.

Adult↗
PubMed1988

Comparative efficacy of ciprofloxacin, ceftazidime and gentamicin, given alone or in combination, in a model of experimental septicemia due to Klebsiella pneumoniae in neutropenic mice.

The therapeutic efficacy of ciprofloxacin, used alone and in combination with either ceftazidime or gentamicin, was evaluated in a model of experimental Klebsiella pneumoniae septicemia in neutropenic mice. Therapeutic results were compared to those achieved by treatment with ceftazidime or gentamicin alone, as well as their combination. Infections were induced by i.v. injection of two strains of K. pneumoniae. Therapy with i.m. antibiotics was performed in 8 h intervals for a total of 13 doses, and survival rates were recorded at the end of treatment as well as seven days later. Ciprofloxacin alone proved to be significantly more effective than ceftazidime and gentamicin, producing survival rates similar to the combination of ceftazidime plus gentamicin. Bacterial counts of spleens and blood confirmed the superior bactericidal activity of ciprofloxacin. Except for the combination of ciprofloxacin with ceftazidime, there was no apparent advantage of combinations of ciprofloxacin with the other agents compared to ciprofloxacin alone. These data suggest a high in vivo activity of ciprofloxacin in systemic infection due to K. pneumoniae.

Agranulocytosis↗
PubMed1988

Hemagglutinating and adherence properties of Staphylococcus saprophyticus: epidemiology and virulence in experimental urinary tract infection of rats.

We studied hemagglutinating and adherence properties in Staphylococcus saprophyticus isolates originating from symptomatic urinary tract infections. 12/13 (92%) of strains adhered to Hep cells and 11/13 (85%) were able to agglutinate sheep erythrocytes. Adherence properties differed markedly between strains (P less than 0.0001). Two strains, one hemagglutinating and adherent and one negative for both properties were chosen for experimental urinary tract infections. Results indicate that presence of the hemagglutinin favours colonization of kidney tissue.

Animals↗
PubMed1988

In vitro activity of mecillinam and amoxicillin/clavulanic acid against strains of Escherichia coli producing TEM-1, Oxa-1 and chromosomal beta-lactamases.

The in vitro activity of mecillinam and amoxicillin/clavulanic acid against Escherichia coli strains producing beta-lactamases of the TEM-1, Oxa-1 and chromosomal type were studied using the broth and agar dilution technique. In addition the beta-lactamase activity was determined. The experiments indicated that the beta-lactamase types differed in their influence on the minimum inhibitory concentrations. Both, mecillinam and amoxicillin/clavulanic acid were considerably more active against TEM-1 strains than ampicillin alone, but, with increasing specific beta-lactamase activity, a decrease of susceptibility was found. Strains producing Oxa-1 and chromosomal beta-lactamases usually where highly susceptible to mecillinam but only moderately sensitive or resistant to the combination of amoxicillin/clavulanic acid. In vitro activity of TEM-1 E. coli to mecillinam was strongly reduced when tested in a broth dilution technique. These test systems, however, did not affect the susceptibility of Oxa-1 and chromosomal beta-lactamase producing E. coli strains to either antibiotic.

Amdinocillin↗
PubMed1987

Fosfomycin protects against tubulotoxicity induced by cis-diaminedichloroplatin and cyclosporin A in the rat.

The nephroprotective effect of fosfomycin against tubulotoxicity induced by cis-diaminedichloroplatin (DDP) and cyclosporin A (Cs) was studied in the rat. The parameter of nephrotoxicity was urinary tubular cell excretion. The experiments revealed that fosfomycin, given either concomitantly or in advance was able to reduce the nephrotoxic effect of DDP and Cs significantly. We conclude from these studies that fosfomycin is a broad-spectrum nephroprotective agent.

Animals↗
PubMed1987

[Experimental studies of the nephroprotective effect of fosfomycin].

We studied in an experimental rat model, if fosfomycin reduces the tubulotoxicity induced by tobramycin, teicoplanin, cisplatin or ciclosporine A and is thus a nephroprotective agent. 10 female wistar rats per dose and compound were used, measures of tubulotoxicity were urinary excretion rates of tubular cells and malate dehydrogenase on 5 successive days. Fosfomycin proved to be a potent nephroprotector against all 4 nephrotoxins. Its activity was not based on pharmacokinetic interactions but on a pharmacodynamic effect. Presumably, fosfomycin stabilises the membranes of lysosomes in tubular cells.

Acute Kidney Injury↗
PubMed1987

Teicoplanin: renal tolerance and pharmacokinetics in rats.

The nephrotoxicity and pharmacokinetics of teicoplanin were studied in an experimental rat model. Nephrotoxicity was assessed by measuring urinary excretion of tubular cells and malate dehydrogenase. The experiments revealed that 1 mg/kg or more of teicoplanin daily resulted in an increase of excretion rates of tubular cells. Similarly to vancomycin, teicoplanin is accumulated in the kidneys. Nephrotoxicity induced by teicoplanin can be reduced by coadministration of fosfomycin and D-glucaro-1.5-lactam, and enhanced by administration of tobramycin. We conclude that renal function should be monitored closely during teicoplanin therapy.

Animals↗
PubMed1987

[Bacteriologic studies in premature rupture of fetal membranes and correlation with the clinical aspects of chorioamnionitis and the amnion infection syndrome].

One of the major complications following premature rupture of the membranes (PROM) is ascending infection. In this aspect the bacteria of the vaginal flora play a major part. Bacterial spectra of a group with PROM and another control group with punctual rupture of the membranes are comparatively analysed. This analysis is based on swabs taken from vagina and newborns. Data are interpreted in correlation to clinical picture of chorioamnionitis and amnion infection syndrome (AIS). Twelve newborns clinical suspected to have a neonatal infection are retrospectively judged. In the group with pregnant women with PROM potential pathological germs such as group B streptococci and E. coli are found more often, whereas physiological flora, specially Lactobacillus species, are clearly reduced. In newborns with AIS even germs can be detected, which so far have seemed to be more apathogenic, such as Gardnerella vaginalis. Bacteriological findings are discussed in connection with clinical parameters, specially group B streptococci are looked at more precisely. In newborns with AIS microbiological results are demonstrated including course of pregnancy and delivery. For the management of PROM alternatives are shown and advice for prophylaxis is given.

Bacteria↗
PubMed1986

Comparative efficacy of different beta-lactam antibiotics and gentamicin in Klebsiella pneumoniae septicaemia in neutropenic mice.

The in-vivo activity of ceftazidime, cefotetan, imipenem/cilastatin, piperacillin and gentamicin against two strains of Klebsiella pneumoniae was evaluated in a model of experimental septicaemia in neuropenic mice. Single agent therapy with the aminoglycoside was highly effective against both strains. Among the beta-lactams, ceftazidime and cefotetan were nearly as active as gentamicin, whereas imipenem/cilastatin was slightly less effective, and the results achieved with piperacillin were markedly inferior.

Animals↗
PubMed1986

Contribution of cloned virulence factors from uropathogenic Escherichia coli strains to nephropathogenicity in an experimental rat pyelonephritis model.

Escherichia coli 536 (O6:K15:H31), which was isolated from a case of urinary tract infection, determines high nephropathogenicity in a rat pyelonephritis system as measured by renal bacterial counts 7 days after infection. The loss of S fimbrial adhesin formation (Sfa-) (mannose-resistant hemagglutination [Mrh-] and fimbria production [Fim-]), serum resistance (Sre-), and hemolysin production (Hly-) in the mutant 536-21 led to a dramatic reduction of bacterial counts from almost 10(5) to only 40 cells per g of kidney. The reintroduction of the cloned S fimbrial adhesin determinant (sfa) increases the virulence of the avirulent mutant strain by a factor of 20; almost the same effect was observed after restoration of serum resistance by integration of an sfa+ recombinant cosmid into the chromosome. Additional reintroduction of the Hly+ phenotype by transformation of two hly determinants increased the virulence of the strains. Hemolysin production determined increased renal elimination of leukocytes and erythrocytes. Thus all three determinants investigated, S fimbriae, serum resistance, and hemolysin, contribute to the multifactorial phenomenon of E. coli nephropathogenicity.

Adhesins, Escherichia coli↗