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Biomedical subjects

K Botzenhart

Publications and source records attributed to K Botzenhart.

At least 55 records · Page 3Linked to original sources
PubMed1987

Susceptibility of Bordetella pertussis and Bordetella parapertussis to 24 antibiotics.

The susceptibility of Bordetella pertussis (28 strains) and Bordetella parapertussis (6 strains) to 24 antibiotics (penicillin and cephalosporin derivatives, erythromycin, josamycin, cotrimoxazole, imipenem, aztreonam and fosfomycin) was studied by means of the agar dilution method using charcoal horse blood agar. Piperacillin and mezlocillin showed the highest activity (MIC 0.0039-0.00781 micrograms/ml) against B. pertussis while B. parapertussis was most susceptible to piperacillin (0.03125-0.0625 microgram/ml), mezlocillin and latamoxef (0.125-0.25 microgram/ml).

Anti-Bacterial Agents↗
PubMed1987

Relevance of host-derived and bacterial factors in Pseudomonas aeruginosa corneal infections.

Two pathogenic mechanisms of Pseudomonas aeruginosa corneal infections are discussed, one involving bacterial exoenzymes, the other involving polymorphonuclear leukocyte (PMN)-derived lysosomal enzymes. The objective of the present study was (1) to show the relative importance of the two mechanisms and (2) to evaluate the effect of active immunization against P. aeruginosa exoenzymes on ocular damage. Rabbits were immunized against P. aeruginosa alkaline protease (AP) or elastase (Ela) and challenged with the respective enzymes. Corneal damage was studied by light photography (LP). In another group, rabbits were immunized against AP, Ela and exotoxin A (ExoA) and challenged with P. aeruginosa strains PA01 or PA103. Corneal damage was studied with LP, light microscopy, and electron microscopy. Immunized animals were totally protected against intracorneal inoculation of P. aeruginosa proteases. Twelve hr and 24 hr after challenge with whole bacteria, immunized rabbits revealed less corneal damage than non-immunized animals. However, after 48 hr corneal damage (ie severe corneal ulceration) was comparable in both groups. The study suggests that corneal damage involving lysosomal enzymes from stimulated PMN is more important after bacterial infection than direct damage by P. aeruginosa exoenzymes.

Animals↗
PubMed1986

Elastase from polymorphonuclear leucocytes: a regulatory enzyme in immune complex disease.

In sputa of 21 cystic fibrosis patients suffering from chronic Pseudomonas aeruginosa lung infections, activities of lysosomal proteases released from polymorphonuclear leukocytes (PMN) and immune complexes were quantitatively determined. The results showed that low immune complex values correlated with high protease activities and vice versa. In a longitudinal study fluctuating, reciprocal changes of the parameters were observed. Therefore, the hypothesis was investigated as to whether PMN elastase cleaves immune complexes and regulates inflammation. It was shown that treatment of immune complex-positive sputa with PMN elastase decreased IgG and IgA immune complex values and lead to cleavage of the immunoglobulins in the hinge region. PMN elastase-treated samples were not able to stimulate the oxidative burst of PMN. Cleavage of in vitro built immune complexes did not lead to liberation of bound antigen. Western blot analysis of one sputum sample revealed split products of the IgG heavy chain. The results suggest that PMN elastase splits off the Fc portion of immunoglobulins in immune complexes and thus regulates inflammation by a feedback mechanism leading to cyclic inflammatory states.

Antigen-Antibody Complex↗
PubMed1986

Bacterial colonization and occurrence of Legionella pneumophila in warm and cold water, in faucet aerators, and in drains of hospitals.

Warm and cold water as well as water from wash basin drains and faucet aerators was examined to determine the number of viable and dead bacteria by culture and by staining and to establish the spectrum of species with special consideration of Legionella pneumophila. The relation between the number of Legionella pneumophila, the temperature, and the iron content of the water was determined in three separate warm water systems. High colony counts (up to 8.9 X 10(5) colony-forming units), were detected in both warm and cold water at certain sampling sites. The most prevalent genera were Pseudomonas, Bacillus, Flavobacterium, Acinetobacter, and Moraxella. Legionella pneumophila was found in every building in 35 of 150 warm samples and in 1 of 43 cold water samples. The highest water temperature of a sample containing Legionella pneumophila was 64 degrees C. The correlation between high colony counts and the occurrence of Legionella pneumophila in the samples was not significant. High iron concentrations, however, appear to have a positive effect on the growth of Legionella pneumophila.

Equipment and Supplies, Hospital↗
PubMed1986

[In vitro erythrophagocytosis in detecting opsonizing antibodies in a patient with Malta fever. A hypothesis on the explanation of in vivo hemophagocytosis in other patients with Malta fever].

In vitro agglutination and phagocytosis of erythrocytes by homologous neutrophil granulocytes and monocytes could be observed using the blood of a healthy person (blood group A, Rh+) to detect opsonising antibodies in the serum of a patient with Malta fever (blood group O, Rh+). Agglutination and erythrophagocytosis were independent of complement or the presence of Brucella melitensis. In patients with Malta fever and blood groups O and B, respectively, antibodies could be detected on the surface of erythrocytes of blood group A when used as antigen with the help of an immunofluorescence test. The same happened with a serum of one patient with blood group A. In vivo erythrophagocytosis detected in the bone marrow of patients with Malta fever is, therefore, possibly due to common antigens of erythrocytes of blood group A and B. melitensis.

ABO Blood-Group System↗
PubMed1985

Brucellosis: serological methods compared.

At least 12 persons contracted clinical, and 4 persons subclinical Brucella melitensis infection during a brucellosis epidemic in the spring and summer of 1983 in Southern Germany, a region which had been free of this disease for the past 20 years. All cases of illness were traced to one infected herd of sheep. The presence of antibodies against B. melitensis was examined in 72 sera of infected patients using the following tests: agglutination, Coomb's test, two complement fixation tests with different antigen preparations (CFT 1 and 2), IgG and IgM enzyme-linked immunosorbent assay (ELISA), and opsonophagocytosis; and the occurrence of cross-reacting antibodies against Yersinia enterocolitica O 9 was investigated in the agglutination and complement fixation tests. Sera from 100 blood donors and 112 other people with close contact with sheep were also examined. The results revealed the need to consider an intermediate range in the interpretation of ELISA results--due to elevated values of persons in groups at risk but without clinical signs of illness. In all other tests, however, such persons revealed the same cut-off levels as the general population. Results from all initial sera of infected persons revealed titres of optical densities above the baseline levels determined in the present study, with the exception of the Coomb's and CFT2 tests. The agglutination test, but not brucella CFT2, revealed complete cross-reactivity between Y. enterocolitica O 9 and B. melitensis. ELISA stood out as the only test which is suited to diagnosis of both recent and past infection, since ELISA IgM determination permits conclusions about the time of the onset of illness, and determination of IgG may still yield values above the cut-off level up to 623 days after the onset of illness. In 2 of the 16 infected persons, IgG ELISA was the only test revealing previous infection 424 and 528 days after the onset of illness. A procedural scheme is presented which may help to simplify the diagnosis of brucellosis.

Agglutination Tests↗
PubMed1985

Role of Pseudomonas aeruginosa exoenzymes in lung infections of patients with cystic fibrosis.

We investigated the role of Pseudomonas aeruginosa exoenzymes in cystic fibrosis lung infection in the presence and absence of specific serum antibodies. In sputa of 21 cystic fibrosis patients, concentrations of P. aeruginosa proteases and exotoxin A were determined by sensitive radioimmunoassays. In all sputa, detection of exoenzymes was negative (less than or equal to 10 ng). Positive serum antibody titers to bacterial exoenzymes were found in the majority of patients. Purified immunoglobulin G (IgG) preparations from the sera of two patients revealing specific antibody titers to the bacterial proteases neutralized these enzymes at ratios of 1,000:1 to 5,600:1 (wt/wt). Above the neutralizing capacity of IgG, proteases caused cleavage of IgG; below that level, no enzymatic activity was observed. In vitro incubation of P. aeruginosa elastase, alkaline protease, or exotoxin A with elastase derived from polymorphonuclear leukocytes showed that polymorphonuclear leukocyte elastase: (i) was cleaved by bacterial elastase, (ii) was not inactivated by alkaline protease, and (iii) inactivated exotoxin A. The results suggest that soon after the onset of P. aeruginosa lung infection in cystic fibrosis patients, bacterial proteases, but not exotoxin A, become important virulence factors. The results also suggest that exoenzymes do not directly contribute to lung damage after immune response to bacterial antigens has begun.

Cystic Fibrosis↗
PubMed1985

Bactericidal effects of photochemical smog constituents produced by a flow reactor. III. Communication: determination of mutagenic effects of photochemical smog on E. coli K 12 343/113.

The multipurpose strain E. coli K12 343/113 allows the simultaneous detection of different DNA alterations such as base-pair changes, frameshifts and deletions. The investigations show the detection of mutagenic potency in the mixture which is called photochemical smog, produced by a flow reactor. Responsible for these effects were ozone and hydrocarbon-radicals, but not NOx, hydrocarbons (propene, isobutene, trans-2-butene) and peroxiacetylnitrate (PAN). In the given conditions these mutagenic substances are involved in DNA alterations like base-pair changes and deletions due to the amounts of colonies in the gal+-, MTR-, and arg+-system. No frameshifts could be detected in the nad+-system.

Acetates↗
PubMed1985

[Pseudomonas aeruginosa in the oral cavity: occurrence and age distribution of adult germ carriers].

Among 500 patients of a rural general practice, 4,4% proved to be oropharyngeal carriers of Pseudomonas aeruginosa as shown by examination of mouth rinse fluid through enrichment in malachite-green-broth followed by isolation on Pseudosel-Agar at 42 degrees C. Most positive samples were found in persons 54-63 years old. There were no significant sex differences. The isolation of Ps. aeruginosa showed no relation to visible inflammatory processes in the oral cavity, to dentures, diabetes mellitus, chronic respiratory disease, former antibiotic treatment or smoking habits. The age distribution of the carriers cannot be explained.

Adult↗
PubMed1985

[Demonstration of Clostridium difficile and toxin B in patients at a university clinic].

107 stool specimens from not hospitalized individuals and 69 stool specimens from 61 hospitalized patients (Internal Medicine) were examined for C. difficile and toxin B. Included were 42 specimens of 33 female patients of the department of maxillo-facial surgery, receiving prophylactic clindamycin and 7 samples from the ward staff. From the samples of the first group, C. difficile was isolated in one case (0.93%), whereas 8 out of 61 internal patients (13%) were positive for C. difficile by culture and/or toxin test. In 12 out of 33 surgical patients (36%), C. difficile and/or toxin could be detected in the stool. Examination of the ward staff was negative. Environmental samplings on the ward, comprehending 246 contact cultures, resulted in the isolation of C. difficile from 25 plates (10.1%). The majority of the patients showed no symptoms or slight diarrhea. Only 5 patients required vancomycin therapy. Frequency and clinical significance of C. difficile isolation is discussed under these aspects.

Bacterial Proteins↗
PubMed1985

[Survival of Campylobacter jejuni in drinking water, river water and sewage].

Campylobacter jejuni (C. jejuni) has not been found by us in raw sewage or anaerobically stabilized sludge. Therefore the survival of C. jejuni has been tested in drinking water, river water and sewage. A suspension of about 10(7) C. jejuni per ml was filled into dialysis tubes which were placed in wire baskets and exposed. Exposition to drinking water was done using two continuously perfused containers in the laboratory, whereas exposition to sewage and river-water was performed at the local sewage treatment plant. Viable C. jejuni numbers per ml were reduced to zero in drinking water during five days starting from 10(6)/ml, in about two days in river water, starting from 10(8)/ml, and one and a half day in untreated sewage, starting from 10(7)/ml. E. coli showed no significant reduction in any of the experiments. Survival of C. jejuni in water seems to be restricted to a few days. The concentration of oxygen or nutrients in the water seems to be without relevance, whereas the most significant variable is temperature, which in our experiments was highest in the sewage and lowest in the drinking water containers.

Campylobacter fetus↗