124 research outputs found
Faecal pollution affects abundance and diversity of aquatic microbial community in anthropo-zoogenically influenced lotic ecosystems
The aquatic microbiota is known to be an important factor in the sustainability of the natural water ecosystems. However, the microbial community also might include pathogens, which result in very serious waterborne diseases in humans and animals. Faecal pollution is the major cause of these diseases. Therefore, it is of immense importance to assess the potential impact of faecal pollution, originating from both anthropogenic and zoogenic sources, on the profile of microbial communities in natural water environments. To this end, the microbial taxonomic diversity of lotic ecosystems in different regions of Norway, representing urban and rural areas, exposed to various levels of faecal pollution, was investigated over the course of a 1-year period. The highest microbial diversity was found in rural water that was the least faecally polluted, while the lowest was found in urban water with the highest faecal contamination. The overall diversity of the aquatic microbial community was significantly reduced in severely polluted water. In addition, the community compositions diverged between waters where the dominant pollution sources were of anthropogenic or zoogenic origin. The results provide new insight into the understanding of how faecal water contamination, specifically that of different origins, influences the microbial diversity of natural waters.publishedVersio
Evaluation of five different cDNA labeling methods for microarrays using spike controls
BACKGROUND: Several different cDNA labeling methods have been developed for microarray based gene expression analysis. We have examined the accuracy and reproducibility of such five commercially available methods in detection of predetermined ratio values from target spike mRNAs (A. thaliana) in a background of total RNA. The five different labeling methods were: direct labeling (CyScribe), indirect labeling (FairPlay™ – aminoallyl), two protocols with dendrimer technology (3DNA(® )Array 50™ and 3DNA(® )submicro™), and hapten-antibody enzymatic labeling (Micromax™ TSA™). Ten spike controls were mixed to give expected Cy5/Cy3 ratios in the range 0.125 to 6.0. The amounts of total RNA used in the labeling reactions ranged from 5 – 50 μg. RESULTS: The 3DNA array 50 and CyScribe labeling methods performed best with respect to relative deviation from the expected values (16% and 17% respectively). These two methods also displayed the best overall accuracy and reproducibility. The FairPlay method had the lowest total experimental variation (22%), but the estimated values were consistently higher than the expected values (36%). TSA had both the largest experimental variation and the largest deviation from the expected values (45% and 48% respectively). CONCLUSION: We demonstrate the usefulness of spike controls in validation and comparison of cDNA labeling methods for microarray experiments
Diverse PAH transcripts in lymphocytes of PKU patients with putative nonsense (G272X, Y356X) and missense (P281L, R408Q) mutations
AbstractThe majority of mutations in the human phenylalanine hydroxylase (PAH) gene that lead to the recessive disease phenylketonuria (PKU) are believed to affect the activity or stability of the PAH enzyme. In this study we have performed in vivo analyses of lymphocyte PAH mRNA from PKU patients homozygous for the PKU missense mutations P281L and R408Q as well as the nonsense mutations G272X and Y356X. The mutations G272X, P281L and R408Q, which are located outside the consensus splice site sequence, result in transcripts with one or more exons skipped in addition to full-length transcripts. The mutation Y356X results in transcripts with one or more exons skipped, but no full-length transcripts. Our findings question the value of functional and structural predictions of mutations at the protein level without analyses of the corresponding transcript
Evidence of rapid change in genetic structure and diversity during range expansion in a recovering large terrestrial carnivore
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Inverse correlation between PDGFC expression and lymphocyte infiltration in human papillary thyroid carcinoma
Background: Members of the PDGF family have been suggested as potential biomarkers for papillary thyroid carcinomas (PTC). However, it is known that both expression and stimulatory effect of PDGF ligands can be affected by inflammatory cytokines. We have performed a microarray study in a collection of PTCs, of which about half the biopsies contained tumour-infiltrating lymphocytes or thyroiditis. To investigate the expression level of PDGF ligands and receptors in PTC we measured the relative mRNA expression of all members of the PDGF family by qRT-PCR in 10 classical PTC, eight clinically aggressive PTC, and five non-neoplastic thyroid specimens, and integrated qRT-PCR data with microarray data to enable us to link PDGF-associated gene expression profiles into networks based on recognized interactions. Finally, we investigated potential influence on PDGF mRNA levels by the presence of tumour-infiltrating lymphocytes. Methods: qRT-PCR was performed on PDGFA, PDGFB, PDGFC, PDGFD, PDGFRA PDGFRB and a selection of lymphocyte specific mRNA transcripts. Semiquantitative assessment of tumourinfiltrating lymphocytes was performed on the adjacent part of the biopsy used for RNA extraction for all biopsies, while direct quantitation by qRT-PCR of lymphocyte-specific mRNA transcripts were performed on RNA also subjected to expression analysis. Relative expression values of PDGF family members were combined with a cDNA microarray dataset and analyzed based on clinical findings and PDGF expression patterns. Ingenuity Pathway Analysis (IPA) was used to elucidate potential molecular interactions and networks. Results: PDGF family members were differentially regulated at the mRNA level in PTC as compared to normal thyroid specimens. Expression of PDGFA (p = 0.003), PDGFB (p = 0.01) and PDGFC (p = 0.006) were significantly up-regulated in PTCs compared to non-neoplastic thyroid tissue. In addition, expression of PDGFC was significantly up-regulated in classical PTCs as compared to clinically aggressive PTCs (p = 0.006), and PDGFRB were significantly up-regulated in clinically aggressive PTCs (p = 0.01) as compared to non-neoplastic tissue. Semiquantitative assessment of lymphocytes correlated well with quantitation of lymphocyte-specific gene expression. Further more, by combining TaqMan and microarray data we found a strong inverse correlation between PDGFC expression and the expression of lymphocyte specific mRNAs. Conclusion: At the mRNA level, several members of the PDGF family are differentially expressed in PTCs as compared to normal thyroid tissue. Of these, only the PDGFC mRNA expression level initially seemed to distinguish classical PTCs from the more aggressive PTCs. However, further investigation showed that PDGFC expression level correlated inversely to the expression of several lymphocyte specific genes, and to the presence of lymphocytes in the biopsies. Thus, we find that PDGFC mRNA expression were down-regulated in biopsies containing infiltrated lymphocytes or thyroiditis. No other PDGF family member could be linked to lymphocyte specific gene expression in our collection of PTCs biopsies
Antimicrobial resistance—Do we share more than companionship with our dogs?
Aims To investigate and compare antimicrobial resistance genes (ARGs) in faeces from cohabiting dogs and owners. Methods and Results DNA from faecal samples from 35 dogs and 35 owners was screened for the presence of 34 clinically relevant ARGs using high throughput qPCR. In total, 24 and 25 different ARGs were present in the dog and owner groups, respectively. The households had a mean of 9.9 ARGs present, with dogs and owners sharing on average 3.3 ARGs. ARGs were shared significantly more in households with dogs over 6 years old (3.5, interquartile range 2.75–5.0) than in households with younger dogs (2.5, interquartile range 2.0–3.0) (p = 0.02). Dogs possessed significantly more mecA and aminoglycoside resistance genes than owners. Conclusions Dogs and owners can act as reservoirs for a broad range of ARGs belonging to several antimicrobial resistance classes. A modest proportion of the same resistance genes were present in both dogs and owners simultaneously, indicating that ARG transmission between the dog and human gut is of minor concern in the absence of antimicrobial selection. Significance and Impact of the Study This study provides insight into the common dog and human gut resistomes, contributing to an improved knowledge base in risk assessments regarding ARG transmission between dogs and humans.Antimicrobial resistance—Do we share more than companionship with our dogs?publishedVersio
Påvisning av bjørn og andre rovdyr i reinbeitedistrikt Beahceveai/Pasvik 5A/5C
-Ved bruk av 10 hårfeller ble det påvist 5 ulike bjørn i kalvingslandet til reinbeitedistrikt 5A/5C fra 15 april til slutten av juni 2015. Det ble også observert individer og sportegn av jerv, gaupe og kongeørn i kalvingslandet. Dataene fra radio-bjeller (Telespor) og e-bjeller (Findmysheep) som ble båret av henholdsvis 20 og 100 simler, indikerte hvordan reinen brukte området og det er også at det er mulig å tolke bevegelsesmønstre og bevegelseshastigheter hos simlene i relasjon til rovdyrene. Ingen av de fem bjørnene var kjent fra området tidligere år og på den andre siden ble det ikke påvist noen av bjørnene som var kjent fra området i 2013 og 2014
Påvisning av bjørn og andre rovdyr i reinbeitedistrikt Beahceveai/Pasvik 5A/5C
-Ved bruk av 10 hårfeller ble det påvist 5 ulike bjørn i kalvingslandet til reinbeitedistrikt 5A/5C fra 15 april til slutten av juni 2015. Det ble også observert individer og sportegn av jerv, gaupe og kongeørn i kalvingslandet. Dataene fra radio-bjeller (Telespor) og e-bjeller (Findmysheep) som ble båret av henholdsvis 20 og 100 simler, indikerte hvordan reinen brukte området og det er også at det er mulig å tolke bevegelsesmønstre og bevegelseshastigheter hos simlene i relasjon til rovdyrene. Ingen av de fem bjørnene var kjent fra området tidligere år og på den andre siden ble det ikke påvist noen av bjørnene som var kjent fra området i 2013 og 2014
Admixture and gene flow from Russia in the recovering Northern European brown bear (Ursus arctos)
Large carnivores were persecuted to near extinction during the last centuries, but have now recovered in some countries. It has been proposed earlier that the recovery of the Northern European brown bear is supported by migration from Russia. We tested this hypothesis by obtaining for the first time continuous sampling of the whole Finnish bear population, which is located centrally between the Russian and Scandinavian bear populations. The Finnish population is assumed to experience high gene flow from Russian Karelia. If so, no or a low degree of genetic differentiation between Finnish and Russian bears could be expected. We have genotyped bears extensively from all over Finland using 12 validated microsatellite markers and compared their genetic composition to bears from Russian Karelia, Sweden, and Norway. Our fine masked investigation identified two overlapping genetic clusters structured by isolation-by-distance in Finland (pairwise FST = 0.025). One cluster included Russian bears, and migration analyses showed a high number of migrants from Russia into Finland, providing evidence of eastern gene flow as an important driver during recovery. In comparison, both clusters excluded bears from Sweden and Norway, and we found no migrants from Finland in either country, indicating that eastern gene flow was probably not important for the population recovery in Scandinavia. Our analyses on different spatial scales suggest
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