Microarray-based Detection of Antibiotic Resisteance Genes in Salmonella

In the presented study, 143 Salmonella isolates belonging to 26 different serovars were screened for the presence of antibiotic resistance genes by microarray analysis. The microarray contained a total of 223 oligonucleotides representing genes encoding for resistance to the following antibiotic classes: aminoglycoside, ß-lactam, chloramphenicol, MLS, sulfonamide, tetracycline, trimethoprim, and vancomycin. To a large extent, the microarray data were consistent to the general findings concerning antibiotic resistance in Salmonella. Most of the analyzed isolates, harbored three or more resistance genes with the highest numbers found in isolates belonging to the Salmonella serovars Typhimurium, Paratyphi B var. Java, Bredeney, Saint Paul and Heidelberg and the only Give isolate investigate

The driftless gas scintillation proportional counter

Wetensch. publicatieFaculteit der Wiskunde en Natuurwetenschappe

Identification of novel Salmonella enterica Serovar Thyphimurium DT104-specific prophage and nonprophage chromosomal sequences among serovar Thyphimurium isolates by genomic subtractive hybridization

Genomic subtractive hybridization was performed between Salmonella enterica serovar Typhimurium LT2 and DT104 to search for novel Salmonella serovar Typhimurium DT104-specific sequences. The subtraction resulted mainly in the isolation of DNA fragments with sequence similarity to phages. Two fragments identified were associated with possible virulence factors. One fragment was identical to irsA of Salmonella serovar Typhimurium ATCC 14028, which is suggested to be involved in macrophage survival. The other fragment was homologous to HldD, an Escherichia coli O157:H7 lipopolysaccharide assembly-related protein. Five selected DNA fragments¿irsA, the HldD homologue, and three fragments with sequence similarity to prophages¿were tested for their presence in 17 Salmonella serovar Typhimurium DT104 isolates and 27 non-DT104 isolates by PCR. All five selected DNA fragments were Salmonella serovar Typhimurium DT104 specific among the serovar Typhimurium isolates tested. These DNA fragments can be useful for better detection and typing of Salmonella serovar Typhimurium DT10

Origins and consequences of technology acquirement by independent-living seniors:Towards an integrative model

Background: Living independently can be challenging for seniors. Technologies are expected to help older adults age in place, yet little empirical research is available on how seniors develop a need for technologies, how they acquire these technologies, and how these subsequently affect their lives. Aging is complex, dynamic and personal. But how does this translate to seniors’ adoption and acceptance of technology? To better understand origins and consequences of technology acquirement by independent-living seniors, an explorative longitudinal qualitative field study was set up. Methods: Home visits were made to 33 community-dwelling seniors living in the Netherlands, on three occasions (2012–2014). Semi-structured interviews were conducted on the timeline of acquirements, and people and factors involved in acquirements. Additionally, participants were interviewed on experiences in using technologies since acquirement. Thematic analysis was employed to analyze interview transcripts, using a realist approach to better understand the contexts, mechanisms and outcomes of technology acquirements. Results: Findings were accumulated in a new conceptual model: The Cycle of Technology Acquirement by Independent-Living Seniors (C-TAILS), which provides an integrative perspective on why and how technologies are acquired, and why these may or may not prove to be appropriate and effective, considering an independent-living senior’s needs and circumstances at a given point in time. We found that externally driven and purely desire-driven acquirements led to a higher risk of suboptimal use and low levels of need satisfaction. Conclusions: Technology acquirement by independent-living seniors may be best characterized as a heterogeneous process with many different origins, pathways and consequences. Furthermore, technologies that are acquired in ways that are not congruent with seniors’ personal needs and circumstances run a higher risk of proving to be ineffective or inappropriate. Yet, these needs and circumstances are subject to change, and the C-TAILS model can be employed to better understand contexts and mechanisms that come into play

Genetic Features Differentiating Bovine, Food, and Human Isolates of Shiga Toxin-Producing Escherichia coli O157 in The Netherlands

The frequency of Escherichia coli O157 genotypes among bovine, food, and human clinical isolates from The Netherlands was studied. Genotyping included the lineage-specific polymorphism assay (LSPA6), the Shiga-toxin-encoding bacteriophage insertion site assay (SBI), and PCR detection and/or subtyping of virulence factors and markers [stx1, stx2a/stx2c, q21/Q933, tir(A255T), and rhsA(C3468G)]. LSPA6 lineage II dominated among bovine isolates (63%), followed by lineage I/II (35.6%) and lineage I (1.4%). In contrast, the majority of the human isolates were typed as lineage I/II (77.6%), followed by lineage I (14.1%) and lineage II (8.2%). Multivariate analysis revealed that the tir(A255T) SNP and the stx2a/stx2c gene variants were the genetic features most differentiating human from bovine isolates. Bovine and food isolates were dominated by stx2c (86.4% and 65.5%, respectively). Among human isolates, the frequency of stx2c was 36.5%, while the frequencies of stx2a and stx2a plus stx2c were 41.2% and 22.4%, respectively. Bovine isolates showed equal distribution of tir(255A) (54.8%) and tir(255T) (45.2%), while human isolates were dominated by the tir(255T) genotype (92.9%). LSPA6 lineage I isolates were all genotype stx2c and tir(255T), while LSPA6 lineage II was dominated by tir(255A) (86.4%) and stx2c (90.9%). LSPA6 lineage I/II isolates were all genotype tir(255T) but showed more variation in stx2 types. The results support the hypothesis that in The Netherlands, the genotypes primarily associated with human disease form a minor subpopulation in the bovine reservoir. Comparison with published data revealed that the distribution of LSPA6 lineages among bovine and human clinical isolates differs considerably between The Netherlands and North Americ

The Ø-/Ú-crystallin multi-gene family: expression and evolution

Contains fulltext : mmubn000001_080164978.pdf (publisher's version ) (Open Access)Promotor : J. Schoenmakers143 p

Association of Endogenous Avian Viral and Endogenous Viral Genes with Feed Conversion and Six-Week Body Weight in Broilers

The consistency of the effect of selection on the frequencies of endogenous avian viral (eav) and endogenous viral (ev) specific restriction fragment length polymorphism (RFLP) bands was studied in two broiler lines selected from a single base population and in an F2 population derived from a reciprocal cross of both lines. One broiler line (FC line) was selected for low feed conversion ratio and the other line (GL line) was selected for high 6-wk body weight. In the F2 population, the band frequencies were determined in groups representing separate tails of the distribution of two production traits, namely, low feed conversion ratio between 29 and 42 d of age and body weight at 42 d of age. The F2 population consisted of 288 females belonging to 24 full-sib families. To rule out family effects, the tails for these production traits were composed by either the best or by the worst female performer for each trait in each full-sib family. In total, 29 HindIII-eav, 34 MspI-eav, and 21 BamHI-ev bands could be distinguished by RFLP analysis. This report describes the influence of selection on 11 potentially interesting bands. Two bands, the 9.5-kb HindIII-eav and the 15-kb MspI-eav band, which were found both in higher frequencies in the parental FC line, were also found in higher (P ≤ .05) frequencies in the F2 tail with a favorable feed conversion ratio. A third band, the 6.5-kb HindIII-eav band, present in lower frequencies in the parental GL line, was also present in lower (P ≤ .05) frequencies in the F2 tail of birds with heavy body weight

Microarray-based Detection of Antibiotic Resisteance Genes in Salmonella

In the presented study, 143 Salmonella isolates belonging to 26 different serovars were screened for the presence of antibiotic resistance genes by microarray analysis. The microarray contained a total of 223 oligonucleotides representing genes encoding for resistance to the following antibiotic classes: aminoglycoside, ß-lactam, chloramphenicol, MLS, sulfonamide, tetracycline, trimethoprim, and vancomycin. To a large extent, the microarray data were consistent to the general findings concerning antibiotic resistance in Salmonella. Most of the analyzed isolates, harbored three or more resistance genes with the highest numbers found in isolates belonging to the Salmonella serovars Typhimurium, Paratyphi B var. Java, Bredeney, Saint Paul and Heidelberg and the only Give isolate investigate