Biomedical subjects

U Ullmann

Publications and source records attributed to U Ullmann.

At least 55 records · Page 3Linked to original sources

PubMed1994

Comparison of the antibody responses to the 77 Klebsiella capsular types in ankylosing spondylitis and various rheumatic diseases.

The production of antibodies to Klebsiella capsular polysaccharides was measured in sera from either HLA-B27-positive (HLA-B27+) or HLA-B27-negative (HLA-B27-) patients with classical ankylosing spondylitis (n = 54). These sera were compared with sera from patients with various rheumatic diseases (n = 82) and HLA-B27+ or HLA-B27- healthy individuals (n = 85). All sera were analyzed by means of an enzyme-linked immunosorbent assay specific to each of the 77 Klebsiella serotypes. The sera from HLA-B27+ patients with ankylosing spondylitis showed a significantly higher antibody frequency to the capsular types K26, K36, and K50 than the sera from HLA-B27- ankylosing spondylitis patients, patients with psoriatic arthritis, systemic lupus erythematosus, rheumatoid arthritis, or reactive arthritis after Yersinia enterocolitica infection, or healthy controls (P < 0.02). The antibodies were of the immunoglobulin G type. No significant antibody response to the other 74 Klebsiella serotypes, noncapsulated mutants of K26, K36, and K50, or preparations of Citrobacter, Serratia, Hafnia, or Morganella spp. or Streptococcus pneumoniae could be detected. The results might suggest a specific association between these capsular types and HLA-B27+ ankylosing spondylitis and might imply their predominance in this disease.

Adolescent↗

PubMed1994

[Microbiological diagnosis of sepsis].

The detection of microorganisms responsible for septicemia from blood and their susceptibility testing against antimicrobial agents is the main requirement to treat this life threatening infection. The sample of specimens, their transport and the handling of blood cultures in the microbiological laboratory are really important, e.g. the number of blood cultures needed, the proper interval between these cultures, the volume of blood cultures and the use of sterile techniques. Recommendations are given for this important management. Conventional methods for blood cultures as well as new automatically working techniques are described.

Fever↗

PubMed1994

[Campylobacter fetus subsp. fetus in a patient with liver cirrhosis].

Campylobacter fetus subsp. fetus infections are very rare in adults but can occur in immunocompromised elderly people and in patients with chronic disease. We describe the clinical case of a 52-year-old woman with alcoholic liver cirrhosis, where we isolated C.fetus subsp. fetus from blood culture.

Campylobacter Infections↗

PubMed1993

Prevalence of Helicobacter pylori in gastrointestinal disorders and concentrations of ciprofloxacin in serum and gastric mucosa.

Endoscopic antral biopsies were obtained from 30 patients with several gastrointestinal disorders and analysed for the presence of H. pylori. This bacterium was present in 80% and 58%, respectively, of patients with either gastric and duodenal ulcers and gastric neoplasm. In none of the healthy individuals, H. pylori could be found. Another 14 patients with various diseases of the stomach, undergoing a major gastric resection, had been treated with 200 mg ciprofloxacin intravenously immediately before the operation. Blood and various tissues samples were taken during the operation. The prevalence of IgG antibodies against H. pylori in these patients was 93%. H. pylori could be determined in 71% of the cases by the urease production; by culture, this was possible in only one case. The mean peak concentration of ciprofloxacin in serum was 5.31 mg/l and 1.17 mg/l, respectively, immediately and 60 min after the end of infusion; in tissues of antrum and duodenum, 1.59 to 1.64 mg/kg and 1.41 to 1.72 mg/kg, respectively, 45-270 min after the infusion. The results show that ciprofloxacin rapidly penetrates into tissues and attains concentrations greater than the MIC90 for H. pylori. However, these concentrations can inhibit the isolation of this microorganism but not its urease activity. This fact could be interpreted by the existence of a nonculturable but metabolically active form of H. pylori. This would explain the high rate of recrudescence following most types of currently applied therapeutic schemes.

Adult↗

PubMed1993

Serotypes, hemagglutinins, siderophore synthesis, and serum resistance of Klebsiella isolates causing human urinary tract infections.

A total of 146 Klebsiella isolates from human asymptomatic bacteriuria (n = 73), cystitis (n = 54), and acute pyelonephritis (n = 19) were examined for the presence of particular virulence factors. Capsular type K2 was the most common serotype observed (13%). This capsule type was prevalent in isolates from asymptomatic bacteriuria and cystitis but not from pyelonephritis. Type 1 fimbriae were found significantly more often in pyelonephritis isolates than among those from asymptomatic and symptomatic lower urinary tract infection (UTI; P < .05), while no marked differences were detected with respect to the distribution of type 3 fimbriae. Serum resistance was more frequent among isolates from symptomatic (26%) than from asymptomatic UTI (18%). Enterochelin was produced by all but 1 of the isolates as determined by a bioassay. In contrast, aerobactin synthesis was rare (3%), with isolates from pyelonephritis showing the highest frequency of aerobactin production (3/19).

Animals↗

PubMed1993

Bacteriocin typing of environmental Klebsiella isolates.

A total of 88 environmental Klebsiella pneumoniae and K. oxytoca isolates were typed according to their bacteriocin susceptibility patterns. Bacteriocin typing was performed by a modification of the scrape-and-point method, using a set of 8 producer strains. This method proved to be very applicable to environmental strains of both species; all but one strain could be typed. Twenty-one different patterns were observed. Type 1-3456-8 was most common in both species. In contrast to K. pneumoniae, more than half of the K. oxytoca strains fell into only two bacteriocin susceptibility patterns. Bacteriocin types 1 and 3 showed a very broad spectrum, more than 95% of the isolates being sensitive to one of these bacteriocins.

Bacteriocins↗

PubMed1992

Isolation of Klebsiella terrigena from clinical specimens.

In a three-year survey conducted from 1988 to 1990 Klebsiella isolates from human clinical specimens were subjected to additional tests to identify any Klebsiella terrigena strains. Ten strains of Klebsiella terrigena (0.4%) were found among 2355 indole-negative Klebsiella isolates. Most of the isolates were recovered from the respiratory tract. In the API20EC system almost exclusively biotypes no. 1777771 and 1777671 were observed. Serotyping revealed capsule types K2, K5 and K18 in two strains each. In antibiotic susceptibility tests the strains were shown to be comparable in sensitivity to Klebsiella pneumoniae.

Anti-Bacterial Agents↗

PubMed1992

Interaction of Klebsiella capsule type 7 with human polymorphonuclear leucocytes.

Klebsiella serotype K7 is found among the capsule types that are most prevalent in respiratory tract isolates. To evaluate the significance of the K7 antigen in bacteria-leucocyte interactions, K7-encapsulated Klebsiella pneumoniae strains and their non-capsulate mutants were investigated. The K7 isolates were compared to K2-capsulate strains and their respective K- derivatives. K7-capsulate bacteria were less hydrophilic, and more readily phagocytosed and killed by human polymorphonuclear leucocytes (PMNL) than K2 strains. Loss of the K7 antigen resulted in increased surface hydrophobicity but did not affect phagocytosis and killing, whereas loss of the K2 capsule caused greater susceptibility to the phagocytic and killing action of PMNL. Both the K7 and K2 antigen stimulated the extracellular release of lysozyme from neutrophils but not of myeloperoxidase, indicating degranulation of only secondary granules. All K- mutants induced the release of both lysozyme and myeloperoxidase. Our results suggest that, in contrast to the K2 antigen, the K7 capsular polysaccharide does not confer antiphagocytic properties on bacteria. However, the K7 antigen is able to impede the extracellular release of primary granule enzymes.

Antigens, Bacterial↗

PubMed1992

Siderophore production of Klebsiella species isolated from different sources.

A total of 481 Klebsiella pneumoniae and K. oxytoca strains isolated from different sources was examined for siderophore production. Screening for siderophore secretion by chrome azurol S agar revealed that 475 strains (98.8%) produced siderophores. The isolates were further investigated for synthesis of enterochelin and aerobactin by means of specific bioassays. Almost all Klebsiella strains (99.4%) excreted enterochelin. Aerobactin production, however, was rarely observed among K. pneumoniae (6%) and K. oxytoca (4%) isolates. The incidence of aerobaction-positive strains was similar in clinical, fecal, and environmental isolates. These results suggest that the aerobactin system does not represent a major mechanism of iron supply in Klebsiella spp.

Enterobactin↗

PubMed1992

Klebsiella capsular type K7 in relation to toxicity, susceptibility to phagocytosis and resistance to serum.

Klebsiella strains possessing capsule type K7 are found predominantly in respiratory secretions. To investigate the importance of this K antigen in virulence, 13 K7 strains were compared with K2 capsulate isolates which are generally regarded as highly virulent. The toxicity of the strains was determined in a mouse peritonitis model. Generally, K7 isolates were significantly less toxic for mice than K2 strains. In the absence of serum, neither capsule type showed much stimulation of leucocytes, measured as the chemiluminescence (CL) response of human polymorphonuclear leucocytes (PMNL). However, in the presence of normal human serum, CL values with K7 strains increased considerably, whereas the CL response to K2 isolates was unaffected. Correspondingly, intracellular killing by PMNL was observed with K7 strains only, whereas K2 isolates proved to be relatively resistant to phagocytic destruction. No correlation was found between capsule type K7 and serum resistance. These data suggest that, in contrast to K2, capsule type K7 may not be a critical factor in the virulence of K7-capsulate Klebsiella strains nor does it seem to act as an antiphagocytic barrier.

Animals↗

PubMed1991

Influence of cefpodoxime on selected immunological functions and bacterial pathogenicity factors in vitro.

The influence of a new oral cephalosporin cefpodoxime, on several interactions of the host-parasite relationship was investigated. Pretreatment of polymorphonuclear granulocytes (PNG) with cefpodoxime at therapeutical dosage in vitro did not have a significant effect on chemotaxis and luminol-dependent chemiluminescence. On the other hand, human serum did not exert a considerable effect on the bactericidal activity of cefpodoxime on Klebsiella pneumoniae and Staph. aureus. Serum resistance of Klebsiella pneumoniae was not altered after pretreatment with cefpodoxime 1/16 MIC (0.03 micrograms/ml) for 3 to 27 hours.

Amphotericin B↗

PubMed1991

A modified procedure for the identification of anaerobic bacteria by high performance liquid chromatography--quantitative analysis of short-chain fatty acids.

We have developed a new rapid method for analysing volatile and non-volatile short-chain fatty acids using high-performance liquid chromatography. Within 50 min, 22 fatty acids in a standard mixture could be detected in a single chromatographic run. The fatty acids released by anaerobic bacteria in the culture media were ether-extracted and analysed with an Aminex HPX-87H column. Using a microprocessor-controlled chromatography unit, a quantitative analysis of the fatty acids produced in bacterial cultures was possible. Resolution, rapidity and sensitivity were improved as compared to previous methods by using an eluent of 5% acetonitrile in 0.01 N H2SO4 and changing the column temperature to 35 degrees C.

Bacteria, Anaerobic↗

PubMed1991

Serum resistance properties of Klebsiella pneumoniae and K. oxytoca isolated from different sources.

A total of 481 K. pneumoniae and K. oxytoca strains from different sources was examined with respect to sensitivity to normal human serum. K. oxytoca strains much more frequently proved to be serum resistant than K. pneumoniae isolates. Environmental strains of both species showed greater serum sensitivity than fecal or clinical isolates. While K. oxytoca strains isolated from feces and clinical specimens showed similar frequencies of serum resistant isolates, fecal K. pneumoniae strains less often were serum resistant than clinical K. pneumoniae isolates. Clinical Klebsiella strains appear to be more related to strains isolated from feces than to those isolated from the environment.

Blood Bactericidal Activity↗

PubMed1991

[Cefmenoxime penetration in human lacrimal sac mucosa after systemic administration].

Access to microbiological, pharmacokinetic and toxicological information is necessary for useful, controlled application of antibiotics in intraocular and periocular infections. It is important to know whether the antibiotic is effective against ophthalmologically relevant bacteria and if suprathreshold concentrations of the antibiotic can be achieved in the contaminated tissue. In the study presented we investigated the usefulness of cefmenoxime in cases of dacryocystitis. Lacrimal sac tissue--and serum specimens were obtained from 15 patients who underwent dacryocystorhinostomy 0.5 to 13 h after intravenous injection of 25 mg cefmenoxime kg. The usual Toti procedure was performed in 7 patients, whereas the other 8 underwent endonasal surgery. Out of the 15 patients 12 suffered from recurrent dacryocystitis. Before application of the antibiotic a serum control sample was obtained in all patients. The highest cefmenoxime levels in the lacrimal sac (72 mg/kg) were measured 30 min after injection. Thirteen hours after the injection, the cefmenoxime levels were too low to be measured. The levels of cefmenoxime in the lacrimal sac tissue were compared with the minimal inhibitory concentrations for the frequent occurrence of bacteria in lacrimal sac infections.

Adolescent↗

PubMed1991

Protease-catalyzed peptide synthesis in frozen aqueous systems: the "freeze-concentration model".

Freezing of the aqueous reaction mixtures can cause dramatically increased peptide yields in protease-catalyzed kinetically controlled peptide synthesis reactions. The "Freeze-concentration model" which implies that the enzymic reaction within a macroscopically frozen system takes place in an unfrozen liquid phase is presented as a reasonable basis for the understanding of the effect of freezing. It is shown that L-amino acid esters are effective nucleophiles in alpha-chymotrypsin-catalyzed acyl transfer reactions when these are performed in frozen state.

Amino Acid Sequence↗

PubMed1991

[Microbial spectrum and microbiological diagnosis of infectious endocarditis].

Still streptococci play the most important role as causatives of infective endocarditis. As change in composition of patient groups has taken place gradually pathogens like Staphylococcus epidermidis, enterococci, gram-negative rods and Candida species become more and more important now. Providing high-level accuracy if applied according to current rules blood culture is yet the basis for endocarditis caused by popular bacterial pathogens. If infection due to Candida species is suspected additional measuring of antibody response may be helpful in supporting the tentative diagnosis. Rare pathogens like Rickettsiae and Mycoplasma sp. must be considered for differential diagnosis, as infections caused by these organisms are to be identified by serological methods in first line.

Candidiasis↗

PubMed1990

Correlation between pharmacokinetics, pharmacodynamics and efficacy of antibacterial agents in animal models.

On the basis of a review of published literature it is demonstrated that pharmacokinetic parameters of antibacterial agents correlate well with therapeutic efficacy in animal models, provided pharmacodynamic parameters are taken into account. The time that serum levels exceed the MIC is the most significant parameter determining efficacy of beta-lactams, whereas the efficacy of aminoglycosides is dependent on serum concentrations and the area under the curve. The efficacy of quinolones tends to be correlated to the doses administered or drug levels achieved. However, specific pharmacodynamic properties contribute significantly to the therapeutic efficacy of a few quinolones only whereas other quinolones lack these specific pharmacodynamic attributes. Thus, the correlation of pharmacokinetic parameters with therapeutic efficacy provides important basic concepts for the design of preclinical and clinical studies in the course of which additional pharmacodynamic properties will become apparent.

Animals↗

PubMed1990

Results of a clinical and pharmacokinetic study of ceftazidime in patients with postoperative pneumonia on assisted ventilation.

Thirty-three patients who developed nosocomial pneumonia postoperatively were treated with ceftazidime, 4-6 g daily, over an average period of 7 days. Twenty-nine patients were evaluated; 13 (45%) patients were cured, five showed improvement, two relapsed, and one could not be assessed. X-rays of the chest showed no infiltrates in 17 out of the 29 cases (59%) after treatment. On the first day of treatment, ceftazidime concentrations in bronchial secretions of nine patients were estimated. The mean values of serum concentrations were: 15 min after infusion, 98 micrograms ml-1; 60 min, 63; 120 min, 44; 360 min, 20; 480 min, 13 micrograms ml-1. The mean values of the corresponding bronchial secretions were 2.9, 5.8, 10.2, 7.11 and 5.2 micrograms ml-1.

Adult↗