Publications by authors named "S Emilia Hannula"

65 Publications

Stimulated saprotrophic fungi in arable soil extend their activity to the rhizosphere and root microbiomes of crop seedlings.

Environ Microbiol 2021 May 10. Epub 2021 May 10.

Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands.

Saprotrophic fungi play an important role in ecosystem functioning and plant performance, but their abundance in intensively managed arable soils is low. Saprotrophic fungal biomass in arable soils can be enhanced with amendments of cellulose-rich materials. Here, we examined if sawdust-stimulated saprotrophic fungi extend their activity to the rhizosphere of crop seedlings and influence the composition and activity of other rhizosphere and root inhabitants. After growing carrot seedlings in sawdust-amended arable soil, we determined fungal and bacterial biomass and community structure in roots, rhizosphere and soil. Utilization of root exudates was assessed by stable isotope probing (SIP) following CO -pulse-labelling of seedlings. This was combined with analysis of lipid fatty acids (PLFA/NLFA-SIP) and nucleic acids (DNA-SIP). Sawdust-stimulated Sordariomycetes colonized the seedling's rhizosphere and roots and actively consumed root exudates. This did not reduce the abundance and activity of bacteria, yet higher proportions of α-Proteobacteria and Bacteroidia were seen. Biomass and activity of mycorrhizal fungi increased with sawdust amendments, whereas exudate consumption and root colonization by functional groups containing plant pathogens did not change. Sawdust amendment of arable soil enhanced abundance and exudate-consuming activity of saprotrophic fungi in the rhizosphere of crop seedlings and promoted potential beneficial microbial groups in root-associated microbiomes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/1462-2920.15563DOI Listing
May 2021

Satisfaction of young ENT surgeons with their work. A Finnish national study.

Int J Circumpolar Health 2021 Dec;80(1):1925445

Department of Otorhinolaryngology, Head and Neck Surgery, University of Helsinki and Helsinki University Hospital, Finland.

The objective was to investigate work satisfaction among recently graduated otorhinolaryngologist - head and neck surgeons - (ENT surgeons). An electronic questionnaire was sent to all ENT surgeons graduated in Finland during a ten-year period. Answers about work satisfaction were analyzed in detail with regards to age, gender, university of specialist training, experience, place of work and further education.Altogether 125/129 (96.9%) responded. The majority (87.8%) of the respondents enjoyed their current main occupation. The older age group (≥40 vs <40 years) was more satisfied (93.7% vs. 81.7%; p=0.042). Consultation opportunities and workplace atmosphere were reported as good by 85.6% and 90.4% of the respondents, respectively. Training opportunities were considered good by 82.4%, albeit by only 60% of the private physicians (p=0.047). Private sector practitioners were also less satisfied with the versatility of their work (p<0.001). Work at a university hospital was considered more strenuous (p<0.001). Over half (54.8%) felt insecure about continuation of their employment status. Most of the recently graduated Finnish ENT surgeons are satisfied with their current occupation, consultation opportunities and workplace atmosphere. However, work at university hospitals in particular was considered often strenuous and over half of the respondents felt insecure about the continuity of their employment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/22423982.2021.1925445DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8118459PMC
December 2021

Evaluation of Phenolic Root Exudates as Stimulants of Saptrophic Fungi in the Rhizosphere.

Front Microbiol 2021 14;12:644046. Epub 2021 Apr 14.

Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, Netherlands.

The rhizosphere microbial community of crop plants in intensively managed arable soils is strongly dominated by bacteria, especially in the initial stages of plant development. In order to establish more diverse and balanced rhizosphere microbiomes, as seen for wild plants, crop variety selection could be based on their ability to promote growth of saprotrophic fungi in the rhizosphere. We hypothesized that this can be achieved by increasing the exudation of phenolic acids, as generally higher fungal abundance is observed in environments with phenolic-rich inputs, such as exudates of older plants and litter leachates. To test this, a rhizosphere simulation microcosm was designed to establish gradual diffusion of root exudate metabolites from sterile sand into arable soil. With this system, we tested the fungus-stimulating effect of eight phenolic acids alone or in combination with primary root metabolites. Ergosterol-based fungal biomass measurements revealed that most phenolic acids did not increase fungal abundance in the arable soil layer. These results were supported by comparison of fungal biomass in the rhizosphere of wild type plants and mutants with altered phenolic acid metabolism. Salicylic acid was the only phenolic acid that stimulated a higher fungal biomass in the arable soil layer of microcosms, but only when combined with a background of primary root metabolites. However, such effect on rhizosphere fungi was not confirmed for a salicylic acid-impaired mutant. For three phenolic acid treatments (chlorogenic acid, salicylic acid, vanillic acid) fungal and bacterial community compositions were analyzed using amplicon sequencing. Despite having little effect on fungal biomass, phenolic acids combined with primary metabolites promoted a higher relative abundance of soil-borne fungi with the ability to invade plant roots ( and spp.) in the simulated rhizosphere. Bacterial community composition was also affected by these phenolic acids. Although this study indicates that phenolic acids do not increase fungal biomass in the rhizosphere, we highlight a potential role of phenolic acids as attractants for root-colonizing fungi.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fmicb.2021.644046DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8079663PMC
April 2021

Perioperative Risk Factors for One-Year Mortality in Patients With Free-Flap Reconstruction Due to Cancer of the Head and Neck.

J Oral Maxillofac Surg 2021 06 6;79(6):1384.e1-1384.e5. Epub 2021 Mar 6.

Professor and Head of Anesthesiology Department, University of Oulu, Medical Research Center, Research Group of Surgery, Anaesthesia and Intensive Care and Department of Anaesthesiology, Oulu University Hospital, Oulu, Finland. Electronic address:

Purpose: Head and neck cancer requiring free-flap reconstruction is associated with relatively high mortality. We aimed to evaluate perioperative risk factors for 1-year mortality in this patient group.

Methods: This is a single-center retrospective analysis of 204 patients operated during 2008 to 2018.

Results: A total of 47 (23.0%) patients died within 1 year. In univariate analysis, there were no differences in the intraoperative course between 1-year survivors and nonsurvivors. Among the 1-year nonsurvivors, preoperative albumin level was lower (39 [36 to 43] vs 42 [39 to 44], P = .032) and the Sequential Organ Failure Assessment admission score was higher (4 [3 to 5] vs 3 [2 to 4], P = .003) than those of the 1-year survivors. Among the nonsurvivors, the preoperative and postoperative levels of leukocytes were higher (7.6 [6.7 to 9.5] vs 6.9 [5.5 to 8.4], P = .002; 11.4 [9.0 to 14.2] vs 8.7 [7.2 to 11.3], P < .001). The highest odds ratios for 1-year mortality in multivariate analysis were American Society of Anesthesiologists A classification greater than 2 (3.9 CI 1.4 to 10.5), male gender (4.0 CI 1.5 to 11), and increase in leukocyte count (1.3 CI 1.1 to 1.5).

Conclusions: One-year nonsurvivors had higher American Society of Anesthesiologists classification and were more often men. The postoperative inflammatory markers were higher in nonsurvivors, while the intraoperative course did not have a significant impact on the 1-year mortality.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.joms.2021.02.042DOI Listing
June 2021

Somatic mutations in lymphocytes in patients with immune-mediated aplastic anemia.

Leukemia 2021 05 30;35(5):1365-1379. Epub 2021 Mar 30.

Hematology Research Unit Helsinki, University of Helsinki and Helsinki University Hospital Comprehensive Cancer Center, Helsinki, Finland.

The prevalence and functional impact of somatic mutations in nonleukemic T cells is not well characterized, although clonal T-cell expansions are common. In immune-mediated aplastic anemia (AA), cytotoxic T-cell expansions are shown to participate in disease pathogenesis. We investigated the mutation profiles of T cells in AA by a custom panel of 2533 genes. We sequenced CD4+ and CD8+ T cells of 24 AA patients and compared the results to 20 healthy controls and whole-exome sequencing of 37 patients with AA. Somatic variants were common both in patients and healthy controls but enriched to AA patients' CD8+ T cells, which accumulated most mutations on JAK-STAT and MAPK pathways. Mutation burden was associated with CD8+ T-cell clonality, assessed by T-cell receptor beta sequencing. To understand the effect of mutations, we performed single-cell sequencing of AA patients carrying STAT3 or other mutations in CD8+ T cells. STAT3 mutated clone was cytotoxic, clearly distinguishable from other CD8+ T cells, and attenuated by successful immunosuppressive treatment. Our results suggest that somatic mutations in T cells are common, associate with clonality, and can alter T-cell phenotype, warranting further investigation of their role in the pathogenesis of AA.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41375-021-01231-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8102188PMC
May 2021