128 results on '"Mikkola R"'
Search Results
2. Community structure of biofilms on ennobled stainless steel in Baltic Sea water
- Author
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Kolari, M, Mattila, K, Mikkola, R, and Salkinoja-Salonen, M S
- Published
- 1998
- Full Text
- View/download PDF
3. Bacillus subtilis and B. mojavensis strains connected to food poisoning produce the heat stable toxin amylosin
- Author
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Apetroaie-Constantin, C., Mikkola, R., Andersson, M. A., Teplova, V., Suominen, I., Johansson, T., and Salkinoja-Salonen, M.
- Published
- 2009
- Full Text
- View/download PDF
4. Acrebol, a novel toxic peptaibol produced by an Acremonium exuviarum indoor isolate
- Author
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Andersson, M. A., Mikkola, R., Raulio, M., Kredics, L., Maijala, P., and Salkinoja-Salonen, M. S.
- Published
- 2009
- Full Text
- View/download PDF
5. The mitochondrial toxin produced by Streptomyces griseus strains isolated from an indoor environment is valinomycin
- Author
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Andersson, M.A., Mikkola, R., Kroppenstedt, R.M., Rainey, F.A., Peltola, J., Sivonen, K., Helin, J., and Salkinoja-Salonen, M.S.
- Subjects
Streptomyces -- Research ,Bacterial toxins -- Research ,Biological sciences - Abstract
A study was conducted to characterize Streptomyces griseus strains emitting a toxin in indoor air and in indoor dust. An Andersen sampler and tryptic soy agar were utilized to collect actinomycetes while electrospray mass spectra were determined with a model API300 triple quadrupole mass spectrometer. Experimental results indicated that S. griseus isolates determined from dust and air in water-damaged buildings generated valinomycin.
- Published
- 1998
6. Antimycin A-producing nonphytopathogenic Streptomyces turgidiscabies from potato
- Author
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Kotiaho, M., Aittamaa, M., Andersson, M. A., Mikkola, R., Valkonen, J. P.T., and Salkinoja-Salonen, M.
- Published
- 2008
7. Penicillium expansum strain isolated from indoor building material was able to grow on gypsum board and emitted guttation droplets containing chaetoglobosins and communesins A, B and D
- Author
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Salo, M. J., Marik, T., Mikkola, R., Andersson, M. A., Kredics, L., Salonen, H., Kurnitski, J., University of Szeged, Structures – Structural Engineering, Mechanics and Computation, Department of Civil Engineering, Aalto-yliopisto, and Aalto University
- Subjects
PATULIN ,HUMAN HEALTH ,Cytotoxicity ,technology, industry, and agriculture ,fungal contamination ,Penicillium ,toxins ,food and beverages ,HOUSE-DUST ,complex mixtures ,TOXICITY ,ALLERGY ,SOIL ,mycotoxins ,MOLD ,LINK ,SPERMATOZOA ,TEMPERATURE - Abstract
Aims Emission of toxic metabolites in guttation droplets of common indoor fungi is not well documented. The aims of this study were (i) to compare mycotoxins in biomass and guttation droplets from indoor fungi from a building following health complaints among occupants, (ii) to identify the most toxic strain and to test if mycotoxins in guttation liquids migrated trough air and (iii) to test if toxigenic Penicillium expansum strains grew on gypsum board. Methods and Results Biomass suspensions and guttation droplets from individual fungal colonies representing Aspergillus, Chaetomium, Penicillium, Stachybotrys and Paecilomyces were screened toxic to mammalian cells. The most toxic strain, RcP61 (CBS 145620), was identified as Pen. expansum Link by sequence analysis of the ITS region and a calmodulin gene fragment, and confirmed by the Westerdijk Institute based on ITS and beta-tubulin sequences. The strain was isolated from a cork liner, was able to grow on gypsum board and to produce toxic substances in biomass extracts and guttation droplets inhibiting proliferation of somatic cells (PK-15, MNA, FL) in up to 20 000-fold dilutions. Toxic compounds in biomass extracts and/or guttation droplets were determined by HPLC and LC-MS. Strain RcP61 produced communesins A, B and D, and chaetoglobosins in guttation droplets (the liquid emitted from them) and biomass extracts. The toxins of the guttation droplets migrated c. 1 cm through air and condensed on a cool surface. Conclusions The mycotoxin-containing guttation liquids emitted by Pen. expansum grown on laboratory medium exhibited airborne migration and were >100 times more toxic in bioassays than guttation droplets produced by indoor isolates of the genera Aspergillus, Chaetomium, Stachybotrys and Paecilomyces. Significance and Impact of the Study Toxic exudates produced by Pen. expansum containing communesins A, B and D, and chaetoglobosins were transferable by air. This may represent a novel mechanism of mycotoxin dispersal in indoor environment.
- Published
- 2019
8. A novel sensitive bioassay for detection of Bacillus cereus emetic toxin and related depsipeptide ionophores
- Author
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Andersson, M.A., Mikkola, R., Helin, J., Andersson, M.C., and Salkinoja-Salonen, M.
- Subjects
Microbiological assay -- Research ,Bacillus cereus -- Research ,Microbial toxins -- Research ,Ionophores -- Research ,Biological sciences - Abstract
Research was conducted to examine a new, sensitive, inexpensive and rapid bioassay for the detection of the emetic toxin of Bacillus cereus. The novel bioassay is based on the motility loss of boar spermatozoa upon 24 h of exposure to emetic B cereus strains extracts or contaminated food. Results indicate swollen mitochondria of the paralyzed spermatozoa but no epetion of cellular ATP or damage to plasma membrane integrity was observed.
- Published
- 1998
9. Purification and characterization of two toxins produced by indoor isolates of bacillus amyloliquefaciens: 2.12-27
- Author
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Mikkola, R, Andersson, M A, Teplova, W, Grigoriev, P, Saris, N EL, Apetroaie, C, Veijalainen, P, Salkinojalonen, M S, and Opanasenko, V
- Published
- 2005
10. Inhibition of human natural killer cell activity by cereulide, an emetic toxin from Bacillus cereus
- Author
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PAANANEN, A., MIKKOLA, R., SARENEVA, T., MATIKAINEN, S., HESS, M., ANDERSSON, M., JULKUNEN, I., SALKINOJA-SALONEN, M. S., and TIMONEN, T.
- Published
- 2002
11. A new method for in vitro detection of microbially produced mitochondrial toxins
- Author
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Hoornstra, D., Andersson, M.A., Mikkola, R., and Salkinoja-Salonen, M.S.
- Published
- 2003
- Full Text
- View/download PDF
12. Penicillium expansum strain isolated from indoor building material was able to grow on gypsum board and emitted guttation droplets containing chaetoglobosins and communesins A, B and D
- Author
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Salo, M.J., primary, Marik, T., additional, Mikkola, R., additional, Andersson, M.A., additional, Kredics, L., additional, Salonen, H., additional, and Kurnitski, J., additional
- Published
- 2019
- Full Text
- View/download PDF
13. Determinants and clinical implications of bleeding related to coronary artery bypass surgery
- Author
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Mikkola, R. (Reija) and Heikkinen, J. (Jouni)
- Subjects
aivoinfarkti ,jääplasma ,aspirin ,fresh frozen plasma ,punasolut ,blood transfusion ,bleeding ,stroke ,verensiirrot ,re-exploration ,verenvuoto ,antikoagulaatio ,veren hyytyminen ,verihiutaleet ,uusintaleikkaus ,platelets ,anticoagulation ,sepelvaltimokirurgia ,coronary artery bypass surgery ,red blood cells ,resternotomy - Abstract
Coronary artery bypass grafting (CABG) is the treatment of choice for patients with three-vessel disease or left main stenosis. However, it is associated with considerable risk of perioperative complications such as myocardial infarction, stroke, infections, and mortality to which excessive bleeding is a contributing factor. This thesis aims to determine the factors involved in and clinical implications of bleeding after CABG. The 1st study evaluated the effects of preoperative ASA discontinuation on the patient’s outcome after CABG. The results showed that late or no discontinuation of low-dose ASA before CABG may decrease the risk of postoperative stroke without increasing the risk of postoperative bleeding. In the 2nd study the use of warfarin was found to be a safe during CABG with no excess bleeding nor other major complications. The 3rd study estimated the impact of surgeons’ performances on blood loss and need for re-exploration after CABG. With 2001 study patients, this study clearly demonstrated that an individual surgeon is a powerful determinant of postoperative bleeding and need for re-exploration after CABG. Using systematic review and meta-analysis, we estimated the risk of complications related to re-exploration for bleeding after CABG. In literature search in 2011, 8 articles with 557 923 patients fulfilled the inclusion criteria. Re-exploration for bleeding after cardiac surgery carries a significantly increased risk of postoperative mortality and morbidity, and thus has a major impact on the patient’s immediate postoperative outcome. We also studied the impact of blood transfusion on the development of post-operative stroke after CABG. Of the study population of 2 226 CABG patients, stroke occurred postoperatively in 53 patients (2.4%). The statistical analysis showed that transfusion of blood products after CABG has a strong, dose-dependent association with the risk of stroke. The use of Octaplas® and platelet transfusions seem to have an even larger impact on the development of stroke than red blood cell transfusions. The 6th study investigated the impact of transfusion of blood products on intermediate outcome after CABG in 2001 patients. The findings indicated that transfusion of any blood product is associated with a significant risk of all-cause and cardiac mortality after CABG. Tiivistelmä Sepelvaltimotauti on yleisin kuolinsyy ja sepelvaltimoiden ohitusleikkaus hyvine pitkäaikaistuloksineen on todettu parhaaksi hoidoksi potilailla, joilla on monen suonen tai vasemman päärungon tauti. Ohitusleikkaukseen liittyy kuitenkin verenvuodon sekä näihin kytkeytyvien komplikaatioiden riski. Tämän väitöskirjan tavoitteena oli määrittää verenvuodon riskitekijöitä sekä verituotteiden siirtojen vaikutusta ohitusleikkauspotilaiden ennusteeseen. Verenhyytymistä estävien lääkkeiden tiedetään lisäävän verenvuotoja. Ensimmäinen tutkimus osoitti, että ASA:n jatkaminen keskeytyksettä ohitusleikkauksissa vähentää aivoinfarktien riskiä lisäämättä silti verenvuodon riskiä. Toisessa tutkimuksessa pitkäaikainen warfariinihoito osoittautui turvalliseksi ohitusleikkauksen aikana eikä sen käyttö lisännyt verenvuotoja eikä muita komplikaatioita. Kolmas tutkimus osoitti kirurgin taidon merkityksen verenvuotojen ja uusintaleikkausten määrään 2001 potilaalla. Verenvuotojen vuoksi tehtävien uusintaleikkausten negatiivinen vaikutus postoperatiiviseen mortaliteettiin sekä morbiditeettiin on todettu yksiselitteisesti useissa tutkimuksissa. Vuonna 2011 tehdyllä systemaattisella kirjallisuuskatsauksella ja meta-analyysillä selvitimme yhteensä 557 923 ohitusleikkauspotilaan aineistosta, että verenvuodon jälkeisiin uusintaleikkauksiin liittyy huomattava kuoleman ja komplikaatioiden riski. Verenvuotoja hoidetaan yleisesti verensiirroilla, vaikkakin useat tutkimukset ovat osoittaneet verituotteiden annon lisäävän mortaliteettia sekä komplikaatioriskiä. Viides tutkimus selvitteli sepelvaltimoleikkauksissa potilaalle annettujen verituotteiden ja leikkauksen yhteydessä sairastettujen aivoinfarktien välistä yhteyttä. Osoittautui, että verituotteiden käyttöön liittyy annosriippuvaisesti lisääntynyt riski saada aivoinfarkti leikkauksen yhteydessä. Varsinkin verihiutale- ja jääplasmasiirtoihin on todettu liittyvän vielä suurempi aivoinfarktin riski kuin punasolusiirtoihin. Kuudes tutkimus selvitteli sepelvaltimoleikkauksien yhteydessä annettujen verituotteiden vaikutusta 2001 potilaan keskipitkään ennusteeseen. Tutkimus osoitti, että minkä tahansa verituotteen antoon sepelvaltimoleikkauksissa liittyy lisääntynyt kuoleman ja sydänkuoleman riski.
- Published
- 2017
14. IndoorTrichodermastrains emitting peptaibols in guttation droplets
- Author
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Castagnoli, E., primary, Marik, T., additional, Mikkola, R., additional, Kredics, L., additional, Andersson, M.A., additional, Salonen, H., additional, and Kurnitski, J., additional
- Published
- 2018
- Full Text
- View/download PDF
15. Determinants and clinical implications of bleeding related to coronary artery bypass surgery
- Author
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Heikkinen, J. (Jouni), Mikkola, R. (Reija), Heikkinen, J. (Jouni), and Mikkola, R. (Reija)
- Abstract
Coronary artery bypass grafting (CABG) is the treatment of choice for patients with three-vessel disease or left main stenosis. However, it is associated with considerable risk of perioperative complications such as myocardial infarction, stroke, infections, and mortality to which excessive bleeding is a contributing factor. This thesis aims to determine the factors involved in and clinical implications of bleeding after CABG. The 1st study evaluated the effects of preoperative ASA discontinuation on the patient’s outcome after CABG. The results showed that late or no discontinuation of low-dose ASA before CABG may decrease the risk of postoperative stroke without increasing the risk of postoperative bleeding. In the 2nd study the use of warfarin was found to be a safe during CABG with no excess bleeding nor other major complications. The 3rd study estimated the impact of surgeons’ performances on blood loss and need for re-exploration after CABG. With 2001 study patients, this study clearly demonstrated that an individual surgeon is a powerful determinant of postoperative bleeding and need for re-exploration after CABG. Using systematic review and meta-analysis, we estimated the risk of complications related to re-exploration for bleeding after CABG. In literature search in 2011, 8 articles with 557 923 patients fulfilled the inclusion criteria. Re-exploration for bleeding after cardiac surgery carries a significantly increased risk of postoperative mortality and morbidity, and thus has a major impact on the patient’s immediate postoperative outcome. We also studied the impact of blood transfusion on the development of post-operative stroke after CABG. Of the study population of 2 226 CABG patients, stroke occurred postoperatively in 53 patients (2.4%). The statistical analysis showed that transfusion of blood products after CABG has a strong, dose-dependent association with the risk of stroke. The use of Octaplas® and platelet transfusions seem to have an, Tiivistelmä Sepelvaltimotauti on yleisin kuolinsyy ja sepelvaltimoiden ohitusleikkaus hyvine pitkäaikaistuloksineen on todettu parhaaksi hoidoksi potilailla, joilla on monen suonen tai vasemman päärungon tauti. Ohitusleikkaukseen liittyy kuitenkin verenvuodon sekä näihin kytkeytyvien komplikaatioiden riski. Tämän väitöskirjan tavoitteena oli määrittää verenvuodon riskitekijöitä sekä verituotteiden siirtojen vaikutusta ohitusleikkauspotilaiden ennusteeseen. Verenhyytymistä estävien lääkkeiden tiedetään lisäävän verenvuotoja. Ensimmäinen tutkimus osoitti, että ASA:n jatkaminen keskeytyksettä ohitusleikkauksissa vähentää aivoinfarktien riskiä lisäämättä silti verenvuodon riskiä. Toisessa tutkimuksessa pitkäaikainen warfariinihoito osoittautui turvalliseksi ohitusleikkauksen aikana eikä sen käyttö lisännyt verenvuotoja eikä muita komplikaatioita. Kolmas tutkimus osoitti kirurgin taidon merkityksen verenvuotojen ja uusintaleikkausten määrään 2001 potilaalla. Verenvuotojen vuoksi tehtävien uusintaleikkausten negatiivinen vaikutus postoperatiiviseen mortaliteettiin sekä morbiditeettiin on todettu yksiselitteisesti useissa tutkimuksissa. Vuonna 2011 tehdyllä systemaattisella kirjallisuuskatsauksella ja meta-analyysillä selvitimme yhteensä 557 923 ohitusleikkauspotilaan aineistosta, että verenvuodon jälkeisiin uusintaleikkauksiin liittyy huomattava kuoleman ja komplikaatioiden riski. Verenvuotoja hoidetaan yleisesti verensiirroilla, vaikkakin useat tutkimukset ovat osoittaneet verituotteiden annon lisäävän mortaliteettia sekä komplikaatioriskiä. Viides tutkimus selvitteli sepelvaltimoleikkauksissa potilaalle annettujen verituotteiden ja leikkauksen yhteydessä sairastettujen aivoinfarktien välistä yhteyttä. Osoittautui, että verituotteiden käyttöön liittyy annosriippuvaisesti lisääntynyt riski saada aivoinfarkti leikkauksen yhteydessä. Varsinkin verihiutale- ja jääplasmasiirtoihin on todettu liittyvän vielä suurempi aivoinfarktin riski kuin punasolusiirtoihin. Kuudes tutkimus
- Published
- 2017
16. The toxic mode of action of cyclic lipodepsipeptide fusaricidins, produced by Paenibacillus polymyxa , toward mammalian cells
- Author
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Mikkola, R., primary, Andersson, M.A., additional, Grigoriev, P., additional, Heinonen, M., additional, and Salkinoja-Salonen, M.S., additional
- Published
- 2017
- Full Text
- View/download PDF
17. Vapor as a carrier of toxicity in a health troubled building
- Author
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Salo, J., Andersson, M. A., Mikkola, R., Laszlo Kredics, Viljanen, M., Salkinoja-Salonen, M., and Department of Food and Nutrition
- Subjects
chaetoglobosin ,cork insulation ,Aspergillus calidoustus ,in vitro toxicity ,indoor moisture ,212 Civil and Construction engineering ,mycotoxin ,sick building ,airborne toxicity ,Aspergillus versicolor ,communesin ,indoor mold ,Penicillium expansum ,antifungal - Abstract
Penicillium expansum was identified as a major contaminant in indoor air, settled dust and materials of several buildings connected to indoor air related health complaints. This fungus emitted large quantities of exudates when cultivated on laboratory media. The exudates proved toxic towards four different mammalian test cells up to 10000 fold dilution. Toxins identified by LC-MS/MS were communesins and chaetoglobosin. Air dispersal of the toxic exudates was investigated with an experimental set-up where natural convection was generated by temperature gradient. It was found that the exudate with the contained toxins became airborne transported from the warmer surface to the colder surface. The results thus demonstrate transportation of microbially produced toxic substances across the air space. The role of liquid emissions from indoor molds represents a novel mechanism for human exposure in mold contaminated buildings. In this paper we report that vapor condensed from the indoor air of building affected with molds Aspergillus versicolor, Aspergillus calidoustus and Penicillium expansum contained substances that were acutely toxic when exposed to mammalian cells in vitro. The results encourage further study of condensed indoor water vapor as a tool to assess the presence of airborne substances with possible adverse health effects.
- Published
- 2015
18. Indoor Trichoderma strains emitting peptaibols in guttation droplets.
- Author
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Castagnoli, E., Marik, T., Mikkola, R., Kredics, L., Andersson, M.A., Salonen, H., and Kurnitski, J.
- Subjects
TRICHODERMA ,SOMATIC cells ,TOXINS ,CELL proliferation ,GYPSUM - Abstract
Aims: The production of peptaibols, toxic secondary metabolites of Trichoderma, in the indoor environment is not well‐documented. Here, we investigated the toxicity of peptaibols in the guttation droplets and biomass of Trichoderma strains isolated from problematic buildings. Methods and Results: Seven indoor‐isolated strains of T. atroviride, T. trixiae, T. paraviridescens and T. citrinoviride were cultivated on malt extract agar, gypsum boards and paperboards. Their biomass extracts and guttation droplets were highly cytotoxic in resting and motile boar sperm cell assays and in inhibition of somatic cell proliferation assays. The toxins were identified with HPLC/ESI‐MS/MS as trichorzianines, trilongins, trichostrigocins and trichostrigocin‐like peptaibols. They exhibited toxicity profiles similar to the reference peptaibols alamethicin, trilongins, and trichorzianine TA IIIc purified from T. atroviride H1/226. Particular Trichoderma strains emitted the same peptaibols in both their biomasses and exudate droplets. The trilongin‐producing T. citrinoviride SJ40 strain grew at 37°C. Conclusions: To our knowledge, this is the first report of indoor‐isolated Trichoderma strains producing toxic peptaibols in their guttation droplets. Significance and Impact of the Study: This report proves that indoor isolates of Trichoderma release peptaibols in their guttation droplets. The presence of toxins in these types of exudates may serve as a mechanism of aerosol formation for nonvolatile toxins in the indoor air. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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19. Optimizing TSV Fill Phases for Improved Fill Rate, Process Stability and Void Performance
- Author
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Ghekiere, J., primary, Mikkola, R., additional, Kebreab, D., additional, Burnham, J., additional, Hoerner, B., additional, and Erickson, D., additional
- Published
- 2015
- Full Text
- View/download PDF
20. Benthic conditions around a historic shipwreck: Vrouw Maria (1771) in the northern Baltic proper
- Author
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Ruuskanen, A.T., primary, Kraufvelin, P., additional, Alvik, R., additional, Díaz, E.R., additional, Honkonen, J., additional, Kanerva, J., additional, Karell, K., additional, Kekäläinen, P., additional, Lappalainen, J., additional, Mikkola, R., additional, Mustasaari, T., additional, Nappu, N., additional, Nieminen, A., additional, Roininen, J., additional, and Svahnbäck, K., additional
- Published
- 2015
- Full Text
- View/download PDF
21. Does Blood Transfusion Affect Intermediate Survival after Coronary Artery Bypass Surgery?
- Author
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Mikkola, R., primary, Heikkinen, J., additional, Lahtinen, J., additional, Paone, R., additional, Juvonen, T., additional, and Biancari, F., additional
- Published
- 2013
- Full Text
- View/download PDF
22. Bacillus subtilisandB. mojavensisstrains connected to food poisoning produce the heat stable toxin amylosin
- Author
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Apetroaie-Constantin, C., primary, Mikkola, R., additional, Andersson, M.A., additional, Teplova, V., additional, Suominen, I., additional, Johansson, T., additional, and Salkinoja-Salonen, M., additional
- Published
- 2009
- Full Text
- View/download PDF
23. Acrebol, a novel toxic peptaibol produced by anAcremonium exuviarumindoor isolate
- Author
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Andersson, M.A., primary, Mikkola, R., additional, Raulio, M., additional, Kredics, L., additional, Maijala, P., additional, and Salkinoja-Salonen, M.S., additional
- Published
- 2009
- Full Text
- View/download PDF
24. Influence of scale-up on the quality of recombinant human growth hormone
- Author
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Bylund, F., Castan, A., Mikkola, R., Veide, Andres, Larsson, G., Bylund, F., Castan, A., Mikkola, R., Veide, Andres, and Larsson, G.
- Abstract
The aerobic fed-batch production of recombinant human growth hormone (rhGH) by Escherichia coli was studied. The goal was to determine the production and protein degradation pattern of this product during fed-batch cultivation and to what extent scale differences depend on the presence of a fed-batch glucose feed zone. Results of laboratory bench-scale, scale-down (SDR), and industrial pilot-scale (3-m(3)) reactor production were compared. In addition to the parameters of product yield and quality, also cell yield, respiration, overflow, mixed acid fermentation, glucose concentration, and cell lysis were studied and compared. The results show that oxygen limitation following glucose overflow was the critical parameter and not the glucose overflow itself. This was verified by the pattern of byproduct formation where formate was the dominating factor and not acetic acid. A correlation between the accumulation of formate, the degree of heterogeneity, and cell lysis was also visualized when recombinant protein was expressed. The production pattern could be mimicked in the SDR reactor for all parameters, except for product quantity and quality, where 30% fewer rhGH-degraded forms were present and where about 80% higher total yield was achieved, resulting in 10% greater accumulation of properly formed rhGH monomer., QC 20100525
- Published
- 2000
- Full Text
- View/download PDF
25. Frigoribacterium faeni gen. nov., sp. nov., a novel psychrophilic genus of the family Microbacteriaceae.
- Author
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Kämpfer, P, primary, Rainey, F A, additional, Andersson, M A, additional, Nurmiaho Lassila, E L, additional, Ulrych, U, additional, Busse, H J, additional, Weiss, N, additional, Mikkola, R, additional, and Salkinoja-Salonen, M, additional
- Published
- 2000
- Full Text
- View/download PDF
26. Influence of scale-up on the quality of recombinant human growth hormone
- Author
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Bylund, F., primary, Castan, A., additional, Mikkola, R., additional, Veide, A., additional, and Larsson, G., additional
- Published
- 2000
- Full Text
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27. Evidence for demand-regulation of ribosome accumulation in E coli
- Author
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Mikkola, R., primary and Kurland, C.G., additional
- Published
- 1991
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28. Is there a unique ribosome phenotype for naturally occurring Escherichia coli?
- Author
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Mikkola, R., primary and Kurland, C.G., additional
- Published
- 1991
- Full Text
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29. A novel sensitive bioassay for detection of Bacillus cereus emetic toxin and related depsipeptide...
- Author
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Mikkola, R., Helin, J., Andersson, M.A., Andersson, M.C., and Salkinoja-Salonen, M.
- Subjects
- *
BIOLOGICAL assay , *BACILLUS cereus - Abstract
Presents a study to describe a bioassay in the detection of Bacillus cereus emetic toxin. Methodology used to conduct study; Indication of findings; Discussion on results.
- Published
- 1998
30. Inhibition of human NK cell function by valinomycin, a toxin from Streptomyces griseus in indoor air.
- Author
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Paananen, A, Mikkola, R, Sareneva, T, Matikainen, S, Andersson, M, Julkunen, I, Salkinoja-Salonen, M S, and Timonen, T
- Abstract
Streptomyces griseus strains isolated from indoor dust have been shown to synthesize valinomycin. In this report, we show that human peripheral blood lymphocytes treated with small doses (30 ng ml(-1)) of pure valinomycin or high-pressure liquid chromatography-pure valinomycin from S. griseus quickly show mitochondrial swelling and reduced NK cell activity. Larger doses (>100 ng/ml(-1)) induced NK cell apoptosis within 2 days. Within 2 h, the toxin at 100 ng ml(-1) dramatically inhibited interleukin-15 (IL-15)- and IL-18-induced granulocyte-macrophage colony-stimulating factor and gamma interferon (IFN-gamma) production by NK cells. However, IFN-gamma production induced by a combination of IL-15 and IL-18 was somewhat less sensitive to valinomycin, suggesting a protective effect of the cytokine combination against valinomycin. Thus, valinomycin in very small doses may profoundly alter the immune response by reducing NK cell cytotoxicity and cytokine production.
- Published
- 2000
31. Selection of laboratory wild-type phenotype from natural isolates of Escherichia coli in chemostats.
- Author
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Mikkola, R and Kurland, C G
- Abstract
We have followed, in glucose-limited chemostats, the evolution of natural isolates of Escherichia coli possessing maximal growth rates of 0.48-1.43 doublings/h. Under these conditions a rapid-growth phenotype similar to that of standard laboratory wild-type strains was selected so that after 280 generations all of the cultures were characterized by bacteria with maximum growth rates close to 1.33 doublings/h. The growth yields of the natural isolates, on the other hand, were quite uniform and improved only slightly during the selection; it seems that the natural isolates are nearly maximally efficient at utilizing glucose. Some of the kinetic characteristics of ribosomes prepared from natural isolates vary markedly and in proportion to the growth rates of the original strains. After growth in glucose-limited chemostats, the ribosomes of all of the cultures become kinetically indistinguishable from those of laboratory wild-type bacteria. These observations confirm the interpretation that bacteria grown under normal laboratory conditions have been selected for maximum growth rates which demand maximum translation efficiency. In contrast, these characteristics do not seem to be strongly selected in the natural isolates.
- Published
- 1992
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32. Developing new toxicological methods to indicate severity of moisture and mold damage in buildings
- Author
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Markkanen, P., Hyvärinen, A., Alenius, H., Salkinoja-Salonen, M., Nevalainen, A., Leino, M., Andersson, M. A., Markkanen, A., Martin Täubel, Matikainen, S., Mikkola, R., Järvi, K., and Hirvonen, M. -R
33. Toxicity Screening of Fungal Extracts and Metabolites, Xenobiotic Chemicals, and Indoor Dusts with In Vitro and Ex Vivo Bioassay Methods.
- Author
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Hintikka T, Andersson MA, Lundell T, Marik T, Kredics L, Mikkola R, Andersson MC, Kurnitski J, and Salonen H
- Abstract
It is controversial how useful bioassays are for identifying the in vivo toxicity of hazardous environmental exposures. In this study, fruiting bodies of forest mushrooms (n = 46), indoor mold colonies (n = 412), fungal secondary metabolites (n = 18), xenobiotic chemicals such as biocides and detergents (n = 6), and methanol extracts of indoor dusts from urban buildings (n = 26) were screened with two different bioactivity assays: boar sperm motility inhibition (BSMI) and inhibition of cell proliferation (ICP) tests. For the forest mushrooms, the toxicity testing result was positive for 100% of poisonous-classified species, 69% of non-edible-classified species, and 18% of edible-classified species. Colonies of 21 isolates of Ascomycota mold fungal species previously isolated from water-damaged buildings proved to be toxic in the tests. Out of the fungal metabolites and xenobiotic chemicals, 94% and 100% were toxic, respectively. Out of the indoor dusts from moldy-classified houses (n = 12) and from dry, mold-free houses (n = 14), 50% and 57% were toxic, respectively. The bioassay tests, however, could not differentiate the samples from indoor dusts of moldy-classified buildings from those from the mold-free buildings. Xenobiotic chemicals and indoor dusts were more toxic in the BSMI assay than in the ICP assay, whereas the opposite results were obtained with the Ascomycota mold colonies and fungal secondary metabolites. The tests recognized unknown methanol-soluble thermoresistant substances in indoor settled dusts. Toxic indoor dusts may indicate a harmful exposure, regardless of whether the toxicity is due to xenobiotic chemicals or microbial metabolites.
- Published
- 2024
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34. Composition of Culturable Microorganisms in Dusts Collected from Sport Facilities in Finland during the COVID-19 Pandemic.
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Andersson MA, Vornanen-Winqvist C, Koivisto T, Varga A, Mikkola R, Kredics L, and Salonen H
- Abstract
Sport facilities represent extreme indoor environments due to intense cleaning and disinfection. The aim of this study was to describe the composition of the cultivated microbiota in dust samples collected in sport facilities during the COVID-19 pandemic. A dust sample is defined as the airborne dust sedimented on 0.02 m
2 within 28 d. The results show that the microbial viable counts in samples of airborne dust ( n = 9) collected from seven Finnish sport facilities during the pandemic contained a high proportion of pathogenic filamentous fungi and a low proportion of bacteria. The microbial viable counts were between 14 CFU and 189 CFU per dust sample. In seven samples from sport facilities, 20-85% of the microbial viable counts were fungi. Out of 123 fungal colonies, 47 colonies belonged to the potentially pathogenic sections of Aspergillus (Sections Fumigati , Nigri , and Flavi ). Representatives of each section were identified as Aspergillus fumigatus , A. flavus , A. niger and A. tubingensis. Six colonies belonged to the genus Paecilomyces. In six samples of dust, a high proportion (50-100%) of the total fungal viable counts consisted of these potentially pathogenic fungi. A total of 70 isolates were considered less likely to be pathogenic, and were identified as Aspergillus section Nidulantes , Chaetomium cochliodes and Penicillium sp. In the rural ( n = 2) and urban ( n = 7) control dust samples, the microbial viable counts were >2000 CFU and between 44 CFU and 215 CFU, respectively, and consisted mainly of bacteria. The low proportion of bacteria and the high proportion of stress tolerant, potentially pathogenic fungi in the dust samples from sport facilities may reflect the influence of disinfection on microbial communities.- Published
- 2023
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35. Aspergillus Was the Dominant Genus Found during Diversity Tracking of Potentially Pathogenic Indoor Fungal Isolates.
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Andersson Aino M, Varga A, Mikkola R, Vornanen-Winqvist C, Salo J, Kredics L, Kocsubé S, and Salonen H
- Abstract
Viable airborne pathogenic fungi represent a potential health hazard when exposing vulnerable persons in quantities exceeding their resilience. In this study, 284 indoor fungal isolates from a strain collection of indoor fungi were screened for pathogenic potential through the ability to grow in neutral pH at 37 °C and 30 °C. The isolates were collected from 20 locations including 14 problematic and 6 non-problematic ordinary buildings. Out of the screened isolates, 170 isolates were unable to grow at 37 °C, whereas 67 isolates growing at pH 7.2 at 37 °C were considered as potential opportunistic pathogens. Forty-seven isolates growing at 30 °C but not at 37 °C were considered as less likely pathogens. Out of these categories, 33 and 33 strains, respectively, were identified to the species level. The problematic buildings included known opportunistic pathogens: Aspergillus calidoustus , Trichoderma longibrachiatum , Rhizopus arrhizus and Paecilomyces variotii , as well as less likely pathogens: Aspergillus versicolor , Chaetomium cochliodes , Chaetomium globosum and Chaetomium rectangulare. Opportunistic pathogens such as Aspergillus flavus, Aspergillus fumigatus , Aspergillus niger and Aspergillus tubingensis and less likely pathogens such as Aspergillus westerdijkiae, Chaetomium globosum and Dichotomopilus finlandicus were isolated both from ordinary and from problematic buildings. Aspergillus was the dominant, most diverse genus found during screening for potentially pathogenic isolates in the indoor strain collection. Studies on Aspergillus niger and Aspergillus calidodoustus revealed that tolerance to cleaning chemicals may contribute to the adaptation of Aspergillus species to indoor environments.
- Published
- 2022
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36. Chaetomium and Chaetomium -like Species from European Indoor Environments Include Dichotomopilus finlandicus sp. nov.
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Kedves O, Kocsubé S, Bata T, Andersson MA, Salo JM, Mikkola R, Salonen H, Szűcs A, Kedves A, Kónya Z, Vágvölgyi C, Magyar D, and Kredics L
- Abstract
The genus Chaetomium is a frequently occurring fungal taxon world-wide. Chaetomium and Chaetomium -like species occur in indoor environments, where they can degrade cellulose-based building materials, thereby causing structural damage. Furthermore, several species of this genus may also cause adverse effects on human health. The aims of this research were to identify Chaetomium and Chaetomium -like strains isolated from indoor environments in Hungary and Finland, two geographically distant regions of Europe with drier and wetter continental climates, respectively, and to study their morphological and physiological properties, as well as their extracellular enzyme activities, thereby comparing the Chaetomium and Chaetomium -like species isolated from these two different regions of Europe and their properties. Chaetomium and Chaetomium -like strains were isolated from flats and offices in Hungary, as well as from schools, flats, and offices in Finland. Fragments of the translation elongation factor 1α ( tef1α ), the second largest subunit of RNA polymerase II ( rpb2 ) and β-tubulin ( tub2 ) genes, as well as the internal transcribed spacer (ITS) region of the ribosomal RNA gene cluster were sequenced, and phylogenetic analysis of the sequences performed. Morphological examinations were performed by stereomicroscopy and scanning electron microscopy. Thirty-one Chaetomium sp. strains (15 from Hungary and 16 from Finland) were examined during the study. The most abundant species was Ch. globosum in both countries. In Hungary, 13 strains were identified as Ch. globosum , 1 as Ch. cochliodes, and 1 as Ch. interruptum . In Finland, 10 strains were Ch. globosum, 2 strains were Ch. cochliodes , 2 were Ch. rectangulare , and 2 isolates (SZMC 26527, SZMC 26529) proved to be representatives of a yet undescribed phylogenetic species from the closely related genus Dichotomopilus , which we formally describe here as the new species Dichotomopilus finlandicus . Growth of the isolates was examined at different temperatures (4, 15, 20, 25, 30, 37, 35, 40, and 45 °C), while their extracellular enzyme production was determined spectrophotometrically.
- Published
- 2021
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37. The effects of paints and moisture content on the indoor air emissions from pinewood (Pinus sylvestris) boards.
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Alapieti T, Castagnoli E, Salo L, Mikkola R, Pasanen P, and Salonen H
- Subjects
- Construction Materials, Environmental Monitoring, Interior Design and Furnishings, Pinus sylvestris, Air Pollution, Indoor, Paint, Volatile Organic Compounds analysis, Wood
- Abstract
The emissions of volatile organic compounds (VOCs) from building materials may significantly contribute to indoor air pollution, and VOCs have been associated with odor annoyance and adverse health effects. Wood materials together with coatings are commonly used indoors for furniture and large surfaces such as walls, floors, and ceilings. This leads to high surface-to-volume ratios, and therefore, these materials may participate remarkably to the VOC levels of indoor environment. We studied emissions of VOCs and carbonyl compounds from pinewood (Pinus sylvestris) boards of 10% and 16% moisture contents (MC) with three paints using small-scale test chambers (27 L). The emissions from uncoated pinewood and paints (on a glass substrate) were tested as references. The 28-day experiment showed that the VOC emissions from uncoated pinewood were lower from sample with 16% MC. Painted pinewood samples showed lower emissions compared to paints on glass substrate. Additionally, paints on 16% MC pinewood exhibited lower emissions than on drier 10% MC wood. The emissions from painted pinewood samples were dominated by paint-based compounds, but the share of wood-based compounds increased over time. However, we noticed differences between the paints, and wood-based emissions were clearly higher with the most permeable paint., (© 2021 The Authors. Indoor Air published by John Wiley & Sons Ltd.)
- Published
- 2021
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38. Melinacidin-Producing Acrostalagmus luteoalbus , a Major Constituent of Mixed Mycobiota Contaminating Insulation Material in an Outdoor Wall.
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Andersson AMA, Salo J, Mikkola R, Marik T, Kredics L, Kurnitski J, and Salonen H
- Abstract
Occupants may complain about indoor air quality in closed spaces where the officially approved standard methods for indoor air quality risk assessment fail to reveal the cause of the problem. This study describes a rare genus not previously detected in Finnish buildings, Acrostalagmus , and its species A. luteoalbus as the major constituents of the mixed microbiota in the wet cork liner from an outdoor wall. Representatives of the genus were also present in the settled dust in offices where occupants suffered from symptoms related to the indoor air. One strain, POB8, was identified as A. luteoalbus by ITS sequencing. The strain produced the immunosuppressive and cytotoxic melinacidins II, III, and IV, as evidenced by mass spectrometry analysis. In addition, the classical toxigenic species indicating water damage, mycoparasitic Trichoderma, Aspergillus section Versicolores, Aspergillus section Circumdati, Aspergillus section Nigri , and Chaetomium spp., were detected in the wet outdoor wall and settled dust from the problematic rooms. The offices exhibited no visible signs of microbial growth, and the airborne load of microbial conidia was too low to explain the reported symptoms. In conclusion, we suggest the possible migration of microbial bioactive metabolites from the wet outdoor wall into indoor spaces as a plausible explanation for the reported complaints.
- Published
- 2021
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39. Identification of Elder Abuse through Out-of-Hospital Emergency Care Providers.
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Salminen-Tuomaala M, Tiainen J, Mikkola R, and Paavilainen E
- Abstract
Background and Purpose: Elder abuse, neglect, and exploitation are under-detected and under-reported. The purpose of this qualitative study was to describe out-ofhospital emergency care providers' experiences of identifying elder abuse., Methods: Individual theme interviews were conducted with nine prehospital emergency care providers and three community paramedics in spring 2019. The transcribed data were analyzed using inductive content analysis., Results: Although the short duration of care contacts made the identification of elder abuse challenging, the emergency care providers detected indicators of physical, psychological and social abuse, unethical action, material exploitation, and self-neglect/self-abuse. The professionals based their observations on patient and family interviews, on clues in the home environment, on caregiving quality combined with the patient's medical history, and on physical signs, which were the easiest to identify., Implications for Practice: The identification of elder abuse may be improved by multiprofessional collaboration, by increased attention given to risk groups and common indicators of abuse, and by adoption or creation of screening tools to assist detection and reporting. Training on the detection of elder abuse should be included in nursing and social work curricula and in the continuing professional development of emergency care providers., (© Copyright 2021 Springer Publishing Company, LLC.)
- Published
- 2021
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40. Exposure to indoor air contaminants in school buildings with and without reported indoor air quality problems.
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Vornanen-Winqvist C, Järvi K, Andersson MA, Duchaine C, Létourneau V, Kedves O, Kredics L, Mikkola R, Kurnitski J, and Salonen H
- Subjects
- Finland, Humans, Particulate Matter analysis, Schools, Ventilation, Air Pollution, Indoor
- Abstract
Reported indoor air quality (IAQ) complaints are common even in relatively new or renovated school buildings in Finland. However, detecting the causes for complaints with commonly used indoor air measurements is difficult. This study presents data on perceived and measured IAQ in six comprehensive school buildings in Finland. The aim of this study was to discover the possible differences of perceived and measured IAQ between schools with reported IAQ complaints and schools without reported IAQ complaints. The initial categorisation of schools with ('problematic schools') and without ('comparison schools') complaints was ensured via a validated indoor climate survey and a recently developed online questionnaire, which were completed by 186 teachers and 1268 students from the six schools. IAQ measurements of physical parameters, gaseous pollutants, particulate matter and bioaerosols were conducted in four problematic school buildings (26 classrooms) and two comparison school buildings (12 classrooms). Using air sampling as well as exhaust air filters and classroom settled dust to detect the presence of elevated concentrations of airborne cultivable microbes and pathogenic, toxigenic and mycoparasitic Trichoderma strains were the most indicative methods in distinguishing problematic schools from comparison schools. Other IAQ-related measurements did not detect clear differences between problematic and comparison schools, as the concentration levels were very low. The results indicate that the complaints reported by occupants could have been related to excess moisture or mould problems that had not been found or repaired. Ventilation pressure condition investigations and simultaneous exhaust and supply air filter dust culture should be addressed precisely in future studies., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2020
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41. Detection of Chaetomium globosum , Ch. cochliodes and Ch. rectangulare during the Diversity Tracking of Mycotoxin-Producing Chaetomium -Like Isolates Obtained in Buildings in Finland.
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Salo JM, Kedves O, Mikkola R, Kredics L, Andersson MA, Kurnitski J, and Salonen H
- Subjects
- Animals, Cell Line, Tumor, Cell Proliferation drug effects, Chaetomium genetics, Finland, Male, Mitochondria drug effects, Mitochondria metabolism, Mycotoxins genetics, Mycotoxins toxicity, Sperm Motility drug effects, Spermatozoa drug effects, Spermatozoa pathology, Sus scrofa, Air Microbiology, Chaetomium metabolism, Dust, Mycotoxins analysis
- Abstract
The diversity of Chaetomium- like isolates in buildings in Finland is poorly documented. This paper describes a set of methods for rapid diversity tracking of 42 indoor Chaetomium -like isolates. These isolates were categorized based on their fluorescence emission, ascomatal hair morphology, responses in three bioassays and resistance/sensitivity to the wetting agent Genapol X-080. Thirty-nine toxigenic isolates were identified [ Ch. globosum ( n = 35), Ch. cochliodes ( n = 2) and Ch. rectangulare ( n = 2)]. These isolates were identified down to the species level by tef1α gene sequencing. The major toxic substances in the ethanol extracts of the Ch. globosum and Ch. cochliodes strains were chaetoglobosin, chaetoviridin A and C, chaetomugilin D and chaetomin, identified based on HPLC-UV and mass spectrometry data (MS and MS/MS). Ethanol extracts from pure Ch. globosum cultures exhibited a toxicological profile in the boar sperm motility inhibition assay (BSMI), sperm membrane integrity damage assay (SMID) and inhibition of cell proliferation (ICP) assay, similar to that exhibited by pure chaetoglobosin A. Overall, differences in fluorescence, morphology, toxicity profile, mycotoxin production and sensitivity to chemicals were consistent with those in tef1α sequencing results for species identification. The results indicate the presence of Ch. cochliodes and Ch. rectangulare in Finnish buildings, representing a new finding.
- Published
- 2020
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42. Screening Mold Colonies by Using Two Toxicity Assays Revealed Indoor Strains of Aspergillus calidoustus Producing Ophiobolins G and K.
- Author
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Salo MJ, Marik T, Bencsik O, Mikkola R, Kredics L, Szekeres A, Andersson MA, Salonen H, and Kurnitski J
- Subjects
- Animals, Aspergillus chemistry, Biological Assay, Biomass, Chromatography, High Pressure Liquid, Dust analysis, Finland, Male, Mass Spectrometry, Mycotoxins isolation & purification, Sesterterpenes isolation & purification, Sperm Motility drug effects, Spermatozoa drug effects, Swine, Tandem Mass Spectrometry, Aspergillus metabolism, Fungi chemistry, Mycotoxins pharmacology, Sesterterpenes pharmacology
- Abstract
The occurrence and toxin production of the opportunistic pathogen Aspergillus calidoustus in Finnish buildings is not well documented in the literature. We tracked and identified four A. calidoustus colonies cultivated from indoor settled dusts and revealed the biological activities of crude biomass extracts. The toxic substances were identified as 6-epi-ophiobolin K, ophiobolin K, and ophiobolin G by high-performance liquid chromatography-mass spectrometry (HPLC-MS) based on chromatographic and mass spectrometry data (MS and MS/MS) on the crude extract of A. calidoustus strain MH34. A total of 29 fungal colonies collected from settled dust in an office room reported for indoor-air-related illnesses were screened for toxins that inhibited boar sperm motility in the BSMI (boar sperm motility inhibiting) assay and cell proliferation in the ICP (inhibition of cell proliferation) assays with PK-15 cells. Out of the 27 colonies tested as toxic, 12 colonies exhibiting conidiophores representative of the genera Chaetomium , Penicillium , and Paecilomyces were excluded from the study, while 13 colonies exhibited Aspergillus-like conidiophores. Biomass suspensions of these colonies were divided into two categories: Category 1 colonies (n = 4), toxic in the BSMI assay and the ICP assays, emitted blue fluorescence and grew at 37 °C; Category 2 colonies (n = 9), only toxic in the ICP assay, emitted orange fluorescence and exhibited limited or no growth at 37 °C. Colonies in Category 1 were pure-cultured, and the strains were named as MH4, MH21, MH34, MH36. Strain MH34 was identified as A. calidoustus by the internal transcribed spacer (ITS) sequences. Ethanol-soluble dry substances extracted from the biomass of the pure cultures exhibited a toxicological profile in the BSMI assay, SMID (sperm membrane integrity damage) assay, and ICP assay similar to that exhibited by pure ophiobolin A. Overall, the viable conidia of A. calidoustus in indoor settled dusts deserve attention when potentially hazardous mold species are monitored., Competing Interests: The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the result.
- Published
- 2019
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43. Emissions of DEHP-free PVC flooring.
- Author
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Castagnoli E, Backlund P, Talvitie O, Tuomi T, Valtanen A, Mikkola R, Hovi H, Leino K, Kurnitski J, and Salonen H
- Subjects
- Adhesives analysis, Alcohols analysis, Environmental Monitoring, Hexanols analysis, Humans, Plasticizers analysis, Volatile Organic Compounds analysis, Air Pollution, Indoor analysis, Environmental Exposure analysis, Floors and Floorcoverings
- Abstract
Degrading 2-ethylhexyl-containing PVC floorings (eg DEHP-PVC floorings) and adhesives emit 2-ethylhexanol (2-EH) in the indoor air. The danger of flooring degradation comes from exposing occupants to harmful phthalates plasticisers (eg DEHP), but not from 2-EH as such. Since the EU banned the use of phthalates in sensitive applications, the market is shifting to use DEHP-free and alternative types of plasticisers in PVC products. However, data on emissions from DEHP-free PVC floorings are scarce. This study aimed at assessing the surface and bulk emissions of two DEHP-free PVC floorings over three years. The floorings were glued on the screed layer of concrete casts at 75%, 85%, and 95% RH. The volatile organic compounds (VOCs) were actively sampled using FLEC (surface emissions) and micro-chamber/thermal extractor (µ-CTE, bulk emissions) onto Tenax TA adsorbents and analyzed with TD-GC-MS. 2-EH, C9-alcohols, and total volatile organic compound (TVOC) emissions are reported. Emissions at 75% and 85% RH were similar. As expected, the highest emissions occurred at 95% RH. 2-EH emissions originated from the adhesive. Because the two DEHP-free floorings tested emitted C9-alcohols at all tested RH, it makes the detection of flooring degradation harder, particularly if the adhesive used does not emit 2-EH., (© 2019 The Authors. Indoor Air published by John Wiley & Sons Ltd.)
- Published
- 2019
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44. Fusaricidin-Type Compounds Create Pores in Mitochondrial and Plasma Membranes of Mammalian Cells.
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Mikkola R, Andersson M, Kharechkina E, Kruglova S, and Kruglov A
- Subjects
- Adenosine Triphosphate metabolism, Alamethicin pharmacology, Animals, Chromatography, High Pressure Liquid, Cytochromes c metabolism, Liver drug effects, Liver metabolism, Male, Mass Spectrometry, Membrane Potentials drug effects, Mitochondrial Membrane Transport Proteins drug effects, Mitochondrial Membrane Transport Proteins metabolism, Mitochondrial Membranes drug effects, Mitochondrial Membranes metabolism, Mitochondrial Permeability Transition Pore, Oxygen Consumption drug effects, Paenibacillus polymyxa chemistry, Rats, Superoxides metabolism, Swine, Bacterial Proteins chemistry, Bacterial Proteins pharmacology, Cell Membrane drug effects, Cell Membrane metabolism, Depsipeptides chemistry, Depsipeptides pharmacology, Mitochondria drug effects, Mitochondria metabolism
- Abstract
Fusaricidins and related LI-F compounds are effective bactericides and fungicides. Recently, we have found that they are highly toxic to mammalian cells. Here, we studied the effect of fusaricidin-type compounds (FTCs) on the membranes of mammalian cells. Ethanol extracts from Paenibacillus polymyxa strains, RS10 and I/Sim, were fractionated and analyzed by HPLC and mass spectrometry. The effects of FTCs on mitochondrial functions and integrity were studied by standard methods: measurements of swelling, membrane potential (ΔΨ
m ), respiration rate, cytochrome c release, and pore sizes. Superoxide flashes were registered by 3,7-dihydro-2-methyl-6-(4-methoxyphenyl)imidazol[1,2-a]pyrazine-3-one (MCLA). Plasma membrane permeability was assessed by propidium iodide (PI) staining and ATP release. FTCs caused the permeabilization of the inner mitochondria membrane (IMM) to ions and low-molecular-weight (~750 Da) solutes. The permeabilization did not depend on the permeability transition pore (mPTP) but was strongly dependent on ΔΨm . Fusaricidins A plus B, LI-F05a, and LI-F05b-LI-F07b permeabilized IMM with comparable efficiency. They created pores and affected mitochondrial functions and integrity similarly to mPTP opening. They permeabilized the sperm cell plasma membrane to ATP and PI. Thus, the formation of pores in polarized membranes underlays the toxicity of FTCs to mammals. Besides, FTCs appeared to be superior reference compounds for mPTP studies., Competing Interests: The authors declare no conflict of interest.- Published
- 2019
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45. Development of a coping model for work-related fear among staff working in emergency department in Finland - study for nursing and medical staff.
- Author
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Mikkola R, Huhtala H, and Paavilainen E
- Subjects
- Adult, Cross-Sectional Studies, Female, Finland, Humans, Male, Middle Aged, Adaptation, Psychological, Emergency Medical Services statistics & numerical data, Fear psychology, Medical Staff psychology, Nursing Staff, Hospital psychology, Stress, Psychological, Workplace psychology
- Abstract
The emergency department is a workplace where the staff regularly encounter new challenges and factors that can cause fear. The aim of this study was to describe coping with work-related fear among emergency department staff. The study explains the current coping methods of emergency department staff and the requirement for support as well as the availability of support. A coping model for work-related fear was also developed and will be presented. The study was conducted using a survey developed specifically for this study, which included the Brief COPE Inventory. The study was conducted in 16 hospitals (N = 544) among the doctors, nurses, practical nurses, and orderlies of the emergency departments. The results were analysed using statistical methods such as frequencies, cross-tabulation, principal component analysis and binary logistic regression analysis. All values of p < 0.05 were considered statistically significant. The results showed that nearly all of the emergency department personnel had experienced work-related fear. Most of the respondents to the survey would have wanted more support, professional help, preventive action and more resources for the emergency department. The emergency department staff had used several coping methods to cope with fear. The most commonly used coping methods were problem-focused coping and social support. Based on the results of the study, it is possible to increase the availability of coping methods and further develop the existing coping methods., (© 2019 Nordic College of Caring Science.)
- Published
- 2019
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46. Emergency patients' and family members' experiences of encountering care providers and receiving care in nonconveyance situations.
- Author
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Salminen-Tuomaala M, Mikkola R, Paavilainen E, and Leikkola P
- Subjects
- Adult, Aged, Cross-Sectional Studies, Female, Humans, Male, Middle Aged, Qualitative Research, Attitude of Health Personnel, Counseling methods, Emergency Medical Services methods, Family psychology, Health Personnel psychology, Patient Satisfaction, Professional-Patient Relations
- Abstract
Background: Not much research has been conducted on emergency patients' and family members' experiences of encountering care providers and receiving care in nonconveyance situations. This knowledge is required to develop the quality and safety of emergency care., Aim: The aim of the study was to describe patients' and family members' experiences concerning encounters with emergency care providers and the patient's care in nonconveyance situations., Methods: The study is a descriptive, cross-sectional survey carried out using quantitative methods. Statistical data were analysed using SPSS Statistics for Windows. The responses to an open question were analysed using inductive content analysis., Results: Patients and family members found that emergency care providers had acted in a professional and friendly manner. They would have expected more psychological support. Family members were less satisfied with the emergency care than patients, especially as regards psychological support and the amount of time given to the patient., Conclusions: Emergency care providers should take the whole family's situation into consideration and seek to promote the family's coping by providing comprehensible counselling and support., (© 2018 Nordic College of Caring Science.)
- Published
- 2018
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47. An Evaluation of Boar Spermatozoa as a Biosensor for the Detection of Sublethal and Lethal Toxicity.
- Author
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Castagnoli E, Salo J, Toivonen MS, Marik T, Mikkola R, Kredics L, Vicente-Carrillo A, Nagy S, Andersson MT, Andersson MA, Kurnitski J, and Salonen H
- Subjects
- Air Pollution, Indoor adverse effects, Animals, Bacteria, Biosensing Techniques, Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone toxicity, Cats, Cell Line, Fungi, Male, Mice, Potassium Dichromate toxicity, Spermatozoa physiology, Swine, Toxins, Biological toxicity, Triclosan toxicity, Sperm Motility drug effects, Spermatozoa drug effects, Toxicity Tests methods
- Abstract
A novel, objective, and rapid computed motility inhibition (CMI) assay was developed to identify and assess sublethal injury in toxin-exposed boar spermatozoa and compared with a subjective visual motility inhibition (VMI) assay. The CMI values were calculated from digital micrographic videos using a custom MATLAB
® script by contrasting the motility index values of each experiment with those of the background and control experiments. Following a comparison of the CMI and VMI assays results, it was determined that their agreement depended on the shape of the dose-response curve. Toxins that exhibited a steep slope were indicative of good agreement between the assays. Those depicted by a gentle decline in the slope of the dose-response curve, the CMI assay were shown to be two times more sensitive than the VMI assay. The CMI assay was highly sensitive to the inhibition of mitochondrial function and glucose transport activity by sublethal doses of toxins and to disruption of cellular cation homeostasis by carrier ionophoric toxins, when compared to the cytotoxicity and lethal toxicity assays (i.e., that evaluated the inhibition of cell proliferation in somatic cell lines (FL, PK-15, and MNA cells)) and disruption to spermatozoa membrane integrity. The CMI assay recognized subtle sublethal toxicity changes in metabolism, manifested as a decrease in boar spermatozoa motility. Thus, it was feasible to effectively compare the objectively-measured numerical values for motility inhibition using the CMI assay against those reflecting lethal damage in the spermatozoa cells and somatic cell lines using a cytotoxicity assay.- Published
- 2018
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48. Emergency Patients' and Family Members' Experiences of Nonconveyance Situations and Counseling Received From Care Providers.
- Author
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Leikkola P, Mikkola R, Salminen-Tuomaala M, and Paavilainen E
- Subjects
- Adult, Aged, Counseling, Cross-Sectional Studies, Female, Humans, Male, Middle Aged, Continuity of Patient Care, Emergency Medical Services, Family psychology, Patients psychology, Professional-Family Relations
- Abstract
Making nonconveyance decisions can be demanding for care providers in prehospital emergency services. Studies have found homecare instructions and counseling of patients and family members partly insufficient. A descriptive cross-sectional design was applied for this pilot study to explore emergency patients' and family members' experiences of nonconveyance situations and counseling. Data were collected by questionnaires from acutely ill patients (n = 97) treated on-site and not transported to hospital and from their family members (n = 72) in 2015-2016. Responses to quantified statements were analyzed statistically, whereas responses to open questions were analyzed using qualitative inductive content analysis. Patients and family members had mostly received verbal home care instructions. Just more than 10% of patients found the instructions insufficient for their coping at home. Male patients were slightly more satisfied with counseling than female patients. One-fifth of female patients but only 6% of male patients were dissatisfied with nonconveyance decisions. In family members, the proportion of dissatisfied respondents was 14%. Older patients were more often dissatisfied than younger patients. Although the majority of the respondents were satisfied with the emergency medical services in general, patients suggested that home care instructions, staff competence, and availability of ambulances should be improved and resources and attention given to patients' opinions increased. Family members proposed more careful assessment of conveyance needs, increased resources, and attention given to the patient. The results highlight the importance of developing a more family-centered approach to emergency care.
- Published
- 2018
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49. Effects of Ventilation Improvement on Measured and Perceived Indoor Air Quality in a School Building with a Hybrid Ventilation System.
- Author
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Vornanen-Winqvist C, Salonen H, Järvi K, Andersson MA, Mikkola R, Marik T, Kredics L, and Kurnitski J
- Subjects
- Air Microbiology standards, Child, Environmental Monitoring, Humans, Trichoderma isolation & purification, Ventilation instrumentation, Air Pollutants analysis, Air Pollution, Indoor analysis, Environmental Exposure analysis, Schools, Ventilation standards
- Abstract
Ventilation system design and operation may significantly affect indoor air quality (IAQ). The aims of this case study were to investigate the functionality of a supply air fan-assisted hybrid ventilation system in a newly built school building with reported IAQ problems and to determine the effects of ventilation improvement on measured and perceived IAQ. The ventilation system function was researched simultaneously with IAQ measurements, with an analysis of total volatile organic compounds (TVOC), single volatile organic compounds (VOCs), and indoor mycobiota, and with questionnaires about perceived IAQ. At the baseline, an operational error of the ventilation system was found, which prevented the air from coming into the classrooms, except for short periods of high carbon dioxide (CO₂) concentrations. After the ventilation operation was improved, a significant change in indoor mycobiota was found; the dominant, opportunistic human pathogenic species Trichoderma citrinoviride found in settled dust in the classroom before the improvement was no longer detected. In addition, the concentrations of CO₂, TVOC, and some single VOCs, especially toluene and decamethylcyclopentasiloxane, decreased. The analysis of the questionnaire results indicated that the perceptions of unpleasant odors and stuffy air decreased, although a statistically significant improvement in perceived IAQ was not observed. The results provided evidence that the properly controlled hybrid ventilation system operating in mechanical supply mode provided adequate ventilation and was effective in decreasing the concentrations of some indoor-generated pollutants. With simple ventilation adjustments, microbiological exposure from building structures might be prevented.
- Published
- 2018
- Full Text
- View/download PDF
50. Out-of-hospital emergency care providers' work and challenges in a changing care environment.
- Author
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Mikkola R, Paavilainen E, Salminen-Tuomaala M, and Leikkola P
- Subjects
- Adult, Female, Finland, Humans, Male, Middle Aged, Surveys and Questionnaires, Young Adult, Emergency Medical Services organization & administration, Emergency Medical Services statistics & numerical data, Emergency Responders psychology, Emergency Responders statistics & numerical data, Health Knowledge, Attitudes, Practice, Job Satisfaction, Professional Competence statistics & numerical data
- Abstract
Acutely ill patients are often treated on site instead of being transported to hospital, so wide-ranging professional competence is required from staff. The aim of this study was to describe and produce new information about out-of-hospital emergency care providers' competence, skills and willingness to engage in self-development activities, and to uncover challenges experienced by care providers in the midst of changing work practices. A quantitative questionnaire was sent to out-of-hospital emergency care providers (N = 142, response rate 53%) of one Finnish hospital district. Data were analysed using spss for Windows 22 software. Almost all respondents found their work interesting and their ability to work independently sufficient. The majority found the work meaningful. Almost 20% felt that work was dominated by constant rush, and 40%, more than half of 25-year-olds but <10% of over 45-years-olds, found the work physically straining. The majority indicated that they had a sufficient theoretical-practical basis to perform their regular duties, and more than one-third felt that they had sufficient skills to deal with multiple patient or disaster situations. Over 20% stated that they were unsure about performing new or infrequent procedures. A number of factors experienced as challenging were revealed. The results provide a basis for improving care providers' initial and further training., (© 2017 Nordic College of Caring Science.)
- Published
- 2018
- Full Text
- View/download PDF
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