Recommended Immunological Strategies to Screen for Botulinum Neurotoxin-Containing Samples

Botulinum neurotoxins (BoNTs) cause the life-threatening neurological illness botulism in humans and animals and are divided into seven serotypes (BoNT/A–G), of which serotypes A, B, E, and F cause the disease in humans. BoNTs are classified as “category A” bioterrorism threat agents and are relevant in the context of the Biological Weapons Convention. An international proficiency test (PT) was conducted to evaluate detection, quantification and discrimination capabilities of 23 expert laboratories from the health, food and security areas. Here we describe three immunological strategies that proved to be successful for the detection and quantification of BoNT/A, B, and E considering the restricted sample volume (1 mL) distributed. To analyze the samples qualitatively and quantitatively, the first strategy was based on sensitive immunoenzymatic and immunochromatographic assays for fast qualitative and quantitative analyses. In the second approach, a bead-based suspension array was used for screening followed by conventional ELISA for quantification. In the third approach, an ELISA plate format assay was used for serotype specific immunodetection of BoNT-cleaved substrates, detecting the activity of the light chain, rather than the toxin protein. The results provide guidance for further steps in quality assurance and highlight problems to address in the future.     

Therapeutic Alliance: What Can be Learned from Case Studies?

Two different video-taped short-term psychotherapies were rated on therapeutic alliance for 27 sessions. The ratings were based on two methods: the Penn Helping Alliance Scales (Penn-HAS) and the Therapeutic Alliance Rating Scale (TARS). Both scales provide separate scores for the therapist and the patient. After checking the reliabilities of the ratings, the strength and course of the alliance formation are compared within and across therapies. Furthermore it was hypothesized that the alliance is structured differently in the two therapies. This hypothesis is tested by making content-specific item comparisons across the therapies for the Penn-HAS and by a comparison of the factor structure over time (factor analytic P-technique) for the TARS.     

Einladung zur Versammlung des FVDZ-Landesverbandes

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