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S Häussler

Publications and source records attributed to S Häussler.

At least 19 recordsLinked to original sources
PubMed1998

Purification and characterization of a cytotoxic exolipid of Burkholderia pseudomallei.

Burkholderia pseudomallei is the causative agent of melioidosis, an infectious disease, which is increasingly recognized as an important public health problem in various tropical regions. This study describes the identification and characterization of a heat-stable extracellular toxin of B. pseudomallei. After cultivation of B. pseudomallei in liquid media, the heated cell-free supernatant was concentrated by ultrafiltration. The concentrate exhibited a cytotoxic and hemolytic activity which showed remarkable resistance against alkaline and acidic treatments. For further purification, reversed-phase chromatography using a fast-performance liquid chromatography system was performed. After elution with an acetonitrile gradient, a single cytotoxic and hemolytic peak was detected. Structural characterization of the toxin was performed by a combination of mass spectrometric and nuclear magnetic resonance spectroscopic techniques. A highly purified glycolipid, 2-O-alpha-L-rhamnopyranosyl-alpha-L-rhamnopyranosyl-beta-hydroxytetradec anoyl-beta-hydroxytetradecanoate (Rha-Rha-C14-C14), with a molecular mass of 762 Da was identified. The purified exolipid showed a time- and dose-dependent cytotoxic effect on phagocytic (HL60) and nonphagocytic (HeLa) cell lines. In addition, a time- and dose-dependent hemolysis of erythrocytes from various species was observed. The toxin structure makes a detergentlike action most probable. Interestingly, the cytotoxic and hemolytic activities of the glycolipid could be neutralized by albumin. Future studies will concentrate on the role of this exolipid as a virulence factor in the pathogenesis of melioidosis.

Animals↗
PubMed1997

Structure of an acidic exopolysaccharide of Burkholderia pseudomallei.

A recently described water-soluble exopolysaccharide of Burkholderia pseudomallei recognized by the IgG 1 monoclonal antibody 3015 [Steinmetz, I., Rohde, M. & Brenneke, B. (1995) Infect. Immun. 63, 3959-3965] was isolated by repetitive ethanol-precipitation steps and by anion-exchange chromatography. The structure of the polysaccharide was determined by a combination of chemical-derivatization and mass-spectrometric techniques (compositional and methylation analysis, GC/MS, and electrospray-ionization-MS/MS of reduced and permethylated hydrolytic fragments), and two-dimensional 1H-NMR methods (COSY, TOCSY and NOESY) and confirmed by isolation and structural characterization of the depolymerized repeating unit of the polysaccharide. The combined structural data established a linear tetrasaccharide repeating unit consisting of three galactose residues, one bearing a 2-linked O-acetyl group, and a 3-deoxy-D-manno-2-octulosonic acid residue. [-->3)-beta-D-Galp2Ac-(1-->4)-alpha-D-Galp-(1-->3)-beta-D-Galp-(1- ->5)-beta-Kdo-(2-->]n

Burkholderia pseudomallei↗
PubMed1994

Monoclonal IgA class-switch variants against bacterial surface antigens: molecular forms and transport into murine respiratory secretions.

The present study describes a new model for passive immunization of the respiratory tract with IgA in comparison to other isotypes. Monoclonal IgA-isotype-switch variants were isolated from different IgG-producing hybridoma clones specific for surface epitopes of bacterial respiratory tract pathogens. Analysis of the molecular form of the IgA variants revealed the simultaneous production of monomeric, dimeric and higher polymeric IgA by a single-cell line with predominance of the polymeric forms. The specificities of the IgA variants were identical to the parent IgG antibodies as demonstrated by inhibition experiments. The IgA variant antibodies were separated into monomers and polymers by gel filtration. Intravenous injection of the different molecular forms of IgA and of IgG into mice were used to investigate the transport characteristics of IgA into murine upper and lower respiratory tract secretions by the physiological route in comparison to IgG. Polymeric IgA variant, monomeric IgA variant and IgG were detected in immunologically active form in both nasal secretion and bronchoalveolar fluid as evidenced by binding to their antigens in an enzyme-linked immunosorbent assay. The relative contribution of the specific exogenous monoclonal IgA and monoclonal IgG to total IgA and IgG, respectively, was determined in secretions. Comparison of the secretion to serum transport ratios clearly indicates selective transport of polymeric IgA variant into nasal secretions relative to IgG parent antibody. Molecular and functional characteristics of the IgA variants make them ideal for passive mucosal immunization experiments and identification of protective epitopes in mucosal immunity.

Animals↗
PubMed1992

[Naturopathy as a contribution to cost control. Attempt at a cost analysis].

OBJECTIVE: A data analysis has been performed to investigate to what extent naturopathy may contribute to reducing costs of medical care. METHODS: The study included anonymous data from the second quarter of 1988 obtained from the North-Württemberg Kassenärztlichen Vereinigung (insurance company). Physicians practicing in this area at that time were compared to a similarly large collective of those designated additionally as naturopaths and/or homeopaths. RESULTS: Differences between the two groups were significant with respect to drug costs and disability certificates however not with respect to physician fees.

Cost Control↗
PubMed1989

[Efficiency of homeopathic preparation combinations in sinusitis. Results of a randomized double blind study with general practitioners].

In a controlled randomized double-blind trial carried out by 47 physicians in private practice with totally 152 patients with sinusitis the therapeutic success of the following homeopathic drug preparations was investigated: Group A: combination of luffa operculata D4, kalium bicromicum D4 and cinnabaris D3. Group B: combination of kalium bicromicum D4 and cinnabaris D3. Group C: luffa operculata D4. Group D: placebo. Criteria for the therapeutic result were headache, blocked nasal breathing, trigeminal tenderness, reddening and swelling of nasal mucosa and postnasal secretion. There was no remarkable difference in the therapeutic success among the investigated homeopathic drug combinations nor between the active drugs and placebo. Averaged over all four groups 81% of the patients with acute sinusitis and 67% of the patients with chronic sinusitis recovered. In the literature comparable therapeutic results are reported for antibiotic therapy, decongestant nose drops and for the drainage of nasal cavities.

Adult↗
PubMed1984

[Work incapacity within the scope of rehabilitation].

The concept of incapacity for work has been defined by a number of court decision. These have, also, considerably widened the originally narrow concept of disease as the cause of incapacity for work, to cover for example hospital diagnostic procedures, elimination of a congenital defect in view of health improvement or prevention of adverse psychic sequelae, addiction, mental disorders, and so on. In cases of step-wise return to working, the incapable-to-work status continues to apply, as in the event of an unsuccessful trial to resume working. When an illness occurs during participation in a retraining programme, incapacity for work is not determined in terms of the former occupation but in the context of the demands posed by the vocational retraining being attended.

Disability Evaluation↗
PubMed1983

[Pollinosis therapy with Galphimia glauca].

Until now the therapy of pollinosis with Galphimia glauca was based on individual experience. We performed a randomized, controlled, multicenter, and double-blind clinical trial to verify the effectiveness of the Galphimia glauca D4 therapy of patients with pollinosis. The average time of observation was 51/2 weeks. Galphimia was found to be more effective than placebo at a 1% level of significance. Therapeutic success was given in 34/41 (= 83%) of the patients with Galphimia and in 21/45 (= 47%) of the control patients.

Adolescent↗