Een maandelijks patroon in aandelenrendementen:een reactie

Een maandelijks patroon in aandelenrendementen: een reacti

Een expertlijst van tijdschriften in de bedrijfswetenschappen

Een expertlijst van tijdschriften in de bedrijfswetenschappe

Diversity of an ectomycorrhizal fungal community studied by a root tip and total soil DNA approach

Molecular methods based on soil DNA extracts are increasingly being used to study the fungal diversity of ectomycorrhizal (EM) fungal communities in soil. Contrary to EM root tip identification, the use of molecular methods enables identification of extramatrical mycelia in soil. To compare fungal diversity as determined by root tip identification and mycelial identification, six soil samples were analysed. Root tips were extracted from the six samples and after amplification, the basidiomycete diversity on the root tips was analysed by denaturing gradient gel electrophoresis (DGGE). The soil from the six samples was sieved, total soil DNA was extracted and after amplification, the basidiomycete diversity in the soil fractions was analysed by DGGE. Fourteen different bands were excised from the DGGE gel and sequenced; fungal taxon names could be assigned to eight bands. Out of a total of 14 fungal taxa detected in soil, 11 fungal taxa were found on root tips, of which seven were EM fungal taxa. To examine whether the sieving treatment would affect EM species diversity, two different sieve mesh sizes were used and in addition, the organic soil fraction was analysed separately. DGGE analysis showed no differences in banding pattern for the different soil fractions. The organic fraction gave the highest DGGE band intensities. This work demonstrates that there is a high correspondence between basidiomycete diversity detected by molecular analysis of root tips and soil samples, irrespective of the soil fraction being analyse

Patients with atopic dermatitis with filaggrin loss-of-function mutations show good but lower responses to immunosuppressive treatment

Filaggrin (FLG) mutations are a strong risk factor to develop atopic dermatitis (AD). However, the relationship between FLG mutations and treatment outcome in AD has not been thoroughly studied. To investigate whether FLG mutations influence immunosuppressive treatment outcome in AD, we studied the effect of FLG mutations in patients with severe AD participating in a single blinded randomized controlled trial (RCT) with methotrexate (MTX) or azathioprine (AZA) during a 24 weeks treatment regimen.((1)) Two years after randomization buccal mucosa swabs were collected from 36 of the 42 RCT patients (86%) to determine the FLG genotype status (R501X, 2282del4, R2447X, S3247X and 3321delA mutations). This article is protected by copyright. All rights reserve

Molecular identification of ectomycorrhizal mycelium in soil horizons

Molecular identification techniques based on total DNA extraction provide a unique tool for identification of mycelium in soil. Using molecular identification techniques, the ectomycorrhizal (EM) fungal community under coniferous vegetation was analyzed. Soil samples were taken at different depths from four horizons of a podzol profile. A basidiomycete-specific primer pair (ITS1F-ITS4B) was used to amplify fungal internal transcribed spacer (ITS) sequences from total DNA extracts of the soil horizons. Amplified basidiomycete DNA was cloned and sequenced, and a selection of the obtained clones was analyzed phylogenetically. Based on sequence similarity, the fungal clone sequences were sorted into 25 different fungal groups, or operational taxonomic units (OTUs). Out of 25 basidiomycete OTUs, 7 OTUs showed high nucleotide homology (greater than or equal to99%) with known EM fungal sequences and 16 were found exclusively in the mineral soil. The taxonomic positions of six OTUs remained unclear. OTU sequences were compared to sequences from morphotyped EM root tips collected from the same sites. Of the 25 OTUs, 10 OTUs had greater than or equal to98% sequence similarity with these EM root tip sequences. The present study demonstrates the use of molecular techniques to identify EM hyphae in various soil types. This approach differs from the conventional method of EM root tip identification and provides a novel approach to examine EM fungal communities in soil