A bead-based suspension array for the detection of Salmonella antibodies in pig sera.

Slaughter pigs are monitored for the presence of the zoonotic pathogen Salmonella, using both serology and bacteriology. ELISAs used to investigate pig herds are based on the detection of antibodies against components of the Salmonella cell envelope. Nearly all Salmonella isolates in food-producing animals are serovars of Salmonella enterica subspecies enterica, distributed over various serogroups as determined by the composition of their lipopolysaccharide (LPS). ELISAs for Salmonella serology are usually based on serogroup B and C1 LPS, often combined with serogroup D or E LPS. Although C2 LPS may improve serology, use of C2 LPS in a broad ELISA was never achieved

Development of a serological Luminex assay for Trichinella and Salmonella in swine

In order to develop veterinary serological multiplex assays, a singleplex bead-based array on the Luminex platform was developed, and with this experience was expanded by building a multiplex serological assay. First a serological Luminex assay was developed for Trichinella in swine

Combined serology and antibiotic residue detection in a Luminex assay

Serum of slaughter pigs is being used for routine testing of antibodies against pathogens and can be used for detection of antibiotic residues. Since the assay formats differ (direct detection of antibodies vs. inhibition assays for residues), these tests are performed in parallel, not in a multiplex set-up. For this study, a protocol for testing both antibodies and residues in one sample was investigated using the deticated multiplex xMAP platform for Luminex

Prevalence of Campylobacter jejuni, Campylobacter lari, and Campylobacter coli in Different Ecological Guilds and Taxa of Migrating Birds

A total of 1,794 migrating birds trapped at a coastal site in southern Sweden were sampled for detection of Campylobacter spp. All isolates phenotypically identified as Campylobacter jejuni and a subset of those identified as non-C. jejuni were identified to the species level by PCR-based techniques. C. jejuni was found in 5.0% of the birds, Campylobacter lari was found in 5.6%, and Campylobacter coli was found in 0.9%. An additional 10.7% of the tested birds were infected with hippurate hydrolysis-negative Campylobacter spp. that were not identified to the species level. The prevalence of Campylobacter spp. differed significantly between ecological guilds of birds. Shoreline-foraging birds feeding on invertebrates and opportunistic feeders were most commonly infected (76.8 and 50.0%, respectively). High prevalence was also shown in other ground-foraging guilds, i.e., ground-foraging invertebrate feeders (11.0%), ground-foraging insectivores (20.3%), and plant-eating species (18.8%). Almost no Campylobacter spp. were found in ground-foraging granivores (2.3%), arboreal insectivores (0.6%), aerial insectivores (0%), or reed- and herbaceous plant-foraging insectivores (3.5%). During the autumn migration, a high proportion of samples from juveniles were positive (7.1% in passerines, 55.0% in shorebirds), indicating transmission on the breeding grounds or during the early part of migration. Prevalence of Campylobacter spp. was associated with increasing body mass among passerine bird species. Furthermore, prevalence was higher in short-distance migrants wintering in Europe than in long-distance migrants wintering in Africa, the Middle East, or Asia. Among ground-foraging birds of the Muscicapidae, those of the subfamily Turdinae (i.e., Turdus spp.) showed a high prevalence of Campylobacter spp., while the organism was not isolated in any member of the subfamily Muscicapinae (i.e., Erithacus and Luscinia). The prevalence of Campylobacter infection in wild birds thus seems to be linked to various ecological and phylogenetic factors, with great variations in carriership between different taxa and guilds

Machine Learning Predicts the Presence of 2,4,6-Trinitrotoluene in Sediments of a Baltic Sea Munitions Dumpsite Using Microbial Community Compositions

Bacteria are ubiquitous and live in complex microbial communities. Due to differences in physiological properties and niche preferences among community members, microbial communities respond in specific ways to environmental drivers, potentially resulting in distinct microbial fingerprints for a given environmental state. As proof of the principle, our goal was to assess the opportunities and limitations of machine learning to detect microbial fingerprints indicating the presence of the munition compound 2,4,6-trinitrotoluene (TNT) in southwestern Baltic Sea sediments. Over 40 environmental variables including grain size distribution, elemental composition, and concentration of munition compounds (mostly at pmol⋅g –1 levels) from 150 sediments collected at the near-to-shore munition dumpsite Kolberger Heide by the German city of Kiel were combined with 16S rRNA gene amplicon sequencing libraries. Prediction was achieved using Random Forests (RFs); the robustness of predictions was validated using Artificial Neural Networks (ANN). To facilitate machine learning with microbiome data we developed the R package phyloseq2ML. Using the most classification-relevant 25 bacterial genera exclusively, potentially representing a TNT-indicative fingerprint, TNT was predicted correctly with up to 81.5% balanced accuracy. False positive classifications indicated that this approach also has the potential to identify samples where the original TNT contamination was no longer detectable. The fact that TNT presence was not among the main drivers of the microbial community composition demonstrates the sensitivity of the approach. Moreover, environmental variables resulted in poorer prediction rates than using microbial fingerprints. Our results suggest that microbial communities can predict even minor influencing factors in complex environments, demonstrating the potential of this approach for the discovery of contamination events over an integrated period of time. Proven for a distinct environment future studies should assess the ability of this approach for environmental monitoring in general

Proof of concept for multiplex detection of antibodies against Chlamydia species in chicken serum using a bead-based suspension array with peptides as antigens

Abstract The available differentiating tests for Chlamydia are based on detection of genetic material and only give information about the actual infection status, but reveal nothing of past infections. As the use of serological methods increases the window of detection, the goal of this study was to investigate if it is possible to develop a differentiating serological test for antibodies against Chlamydia species in chicken sera. Focus was on C. psittaci, C. gallinacea, and two closely related species, i.e. C. abortus and C. avium. To enable differentiating serology, a bead-based Luminex suspension array was constructed, using peptides as antigens, derived from known immunoreactive Chlamydia proteins. For the majority of these peptides, species-specific seroreactivity in mammalian sera has been reported in literature. The suspension array correctly identified antibodies against various Chlamydia species in sera from experimentally infected mice, and was also able to differentiate between antibodies against C. psittaci and C. gallinacea in sera from experimentally infected chickens. In field sera, signals were difficult to interpret as insufficient sera from experimentally infected chickens were available for evaluating the seroreactivity of all peptides. Nevertheless, results of the suspension array with field sera are supported by published data on the occurrence of C. gallinacea in Dutch layers, thereby demonstrating the proof of concept of multiplex serology for Chlamydial species in poultry

Implementation of an innovative web-based conference table for community-dwelling frail older people, their informal caregivers and professionals: a process evaluation

Contains fulltext : 108253.pdf (publisher's version ) (Open Access)ABSTRACT: BACKGROUND: Due to fragmentation of care, continuity of care is often limited in the care provided to frail older people. Further, frail older people are not always enabled to become involved in their own care. Therefore, we developed the Health and Welfare Information Portal (ZWIP), a shared Electronic Health Record combined with a communication tool for community-dwelling frail older people and primary care professionals. This article describes the process evaluation of its implementation, and aims to establish (1) the outcomes of the implementation process, (2) which implementation strategies and barriers and facilitators contributed to these outcomes, and (3) how its future implementation could be improved. METHODS: Mixed methods study, consisting of (1) a survey among professionals (n = 118) and monitoring the use of the ZWIP by frail older people and professionals, followed by (2) semi-structured interviews with purposively selected professionals (n = 12). RESULTS: 290 frail older people and 169 professionals participated in the ZWIP. At the end of the implementation period, 55% of frail older people and informal caregivers, and 84% of professionals had logged on to their ZWIP at least once. For professionals, the exposure to the implementation strategies was generally as planned, they considered the interprofessional educational program and the helpdesk very important strategies. However, frail older people's exposure to the implementation strategies was less than intended. Facilitators for the ZWIP were the perceived need to enhance interprofessional collaboration and the ZWIP application being user-friendly. Barriers included the low computer-literacy of frail older people, a preference for personal communication and limited use of the ZWIP by other professionals and frail older people. Interviewees recommended using the ZWIP for other target populations as well and adding further strategies that may help frail older people to feel more comfortable with computers and the ZWIP. CONCLUSIONS: This study describes the implementation process of an innovative e-health intervention for community-dwelling frail older people, informal caregivers and primary care professionals. As e-health is an important medium for overcoming fragmentation of healthcare and facilitating patient involvement, but its adoption in everyday practice remains a challenge, the positive results of this implementation are promising

Feasibility of a new community-based geriatric intervention programme: An exploration of experiences of GPs, nurses, geriatricians, patients and caregivers.

Contains fulltext : 52166.pdf (publisher's version ) (Closed access