89 results on '"Puranen, T."'
Search Results
2. Hydrolysis and composition of recovered fibres fractionated from solid recovered fuel
- Author
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Kemppainen, K., Siika-aho, M., Östman, A., Sipilä, E., Puranen, T., von Weymarn, N., and Kruus, K.
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- 2014
- Full Text
- View/download PDF
3. Nutritional guidance improves nutrient intake and quality of life, and may prevent falls in aged persons with Alzheimer disease living with a spouse (NuAD trial)
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Suominen, Merja H., Puranen, T. M., Jyväkorpi, S. K., Eloniemi-Sulkava, U., Kautiainen, H., Siljamäki-Ojansuu, U., and Pitkalä, K. H.
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- 2015
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4. Tailored nutritional guidance for home-dwelling AD families: The feasibility of and elements promoting positive changes in diet (NuAD-trial)
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Puranen, T. M., Pitkala, K. H., and Suominen, M. H.
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- 2015
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5. Caregivers’ male gender is associated with poor nutrient intake in AD families (NuAD-trial)
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Puranen, T. M., Pietila, S. E., Pitkala, K. H., Kautiainen, H., Raivio, M., Eloniemi-Sulkava, U., Jyvakorpi, S. K., and Suominen, Merja
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- 2014
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- View/download PDF
6. Omnidirectional microscopy by ultrasonic sample control
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Helander, P., Puranen, T., Meriläinen, A., Maconi, G., Penttilä, A., Gritsevich, M., Kassamakov, I., Salmi, A., Muinonen, K., Hæggström, E., Helander, P., Puranen, T., Meriläinen, A., Maconi, G., Penttilä, A., Gritsevich, M., Kassamakov, I., Salmi, A., Muinonen, K., and Hæggström, E.
- Abstract
Omnidirectional microscopy (OM) is an emerging technology capable of enhancing the three-dimensional (3D) microscopy widely applied in life sciences. In OM, the precise position and orientation control of the sample are required. However, current OM technology relies on destructive mechanical methods to hold the samples, such as embedding samples in gel or attaching them to a needle to permit orientation control. A non-contacting alternative is to levitate the sample. Until now, levitation methods have lacked orientation control. We enable omnidirectional access to the sample by introducing a method to control acoustic levitation that provides precise orientation control. Such control around three axes of rotation permits rapid imaging of the sample from any direction using a fixed camera and subsequent 3D shape reconstruction. The control of non-spherical particles is achieved using an asymmetric acoustic field created with a phase-controlled transducer array. Our technology allows robust 3D imaging of delicate samples and their study in a time-lapse manner. We foresee that the described method is not limited to microscopy and optical imaging, but is also compatible with automated sample handling, light-sheet microscopy, wall-less chemistry, and non-contacting tomography. © 2020 American Institute of Physics Inc.. All rights reserved.
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- 2020
7. Omnidirectional microscopy by ultrasonic sample control
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Helander, P., primary, Puranen, T., additional, Meriläinen, A., additional, Maconi, G., additional, Penttilä, A., additional, Gritsevich, M., additional, Kassamakov, I., additional, Salmi, A., additional, Muinonen, K., additional, and Hæggström, E., additional
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- 2020
- Full Text
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8. Visual food diary - peer support and better diet quality
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Puranen, T, primary, Salokekkila, P, primary, Ahlblad-Makinen, N, primary, and Haggman-Laitila, A, primary
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- 2019
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9. Characterization of Molecular and Catalytic Properties of Intact and Truncated Human 17β-Hydroxysteroid Dehydrogenase Type 2 Enzymes: Intracellular Localization of the Wild-Type Enzyme in the Endoplasmic Reticulum*
- Author
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Puranen, T. J., Kurkela, R. M., Lakkakorpi, J. T., Poutanen, M. H., Itäranta, P. V., Melis, J. P. J., Ghosh, D., Vihko, R. K., and Vihko, P. T.
- Published
- 1999
10. Light scattering by ultrasonically-controlled small particles: System design, calibration, and measurement results
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Kassamakov, I., MacOni, G., Penttilä, A., Helander, P., Gritsevich, M., Puranen, T., Salmi, A., Hæggström, E., Muinonen, K., Kassamakov, I., MacOni, G., Penttilä, A., Helander, P., Gritsevich, M., Puranen, T., Salmi, A., Hæggström, E., and Muinonen, K.
- Abstract
We present the design of a novel scatterometer for precise measurement of the angular Mueller matrix profile of a mm- to μm-sized sample held in place by sound. The scatterometer comprises a tunable multimode Argon-krypton laser (with possibility to set 1 of the 12 wavelengths in visible range), linear polarizers, a reference photomultiplier tube (PMT) for monitoring the beam intensity, and a micro-PMT module mounted radially towards the sample at an adjustable radius. The measurement angle is controlled by a motor-driven rotation stage with an accuracy of 15'. The system is fully automated using LabVIEW, including the FPGA-based data acquisition and the instrument's user interface. The calibration protocol ensures accurate measurements by using a control sphere sample (diameter 3 mm, refractive index of 1.5) fixed first on a static holder followed by accurate multi-wavelength measurements of the same sample levitated ultrasonically. To demonstrate performance of the scatterometer, we conducted detailed measurements of light scattered by a particle derived from the Chelyabinsk meteorite, as well as planetary analogue materials. The measurements are the first of this kind, since they are obtained using controlled spectral angular scattering including linear polarization effects, for arbitrary shaped objects. Thus, our novel approach permits a non-destructive, disturbance-free measurement with control of the orientation and location of the scattering object. © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.
- Published
- 2018
11. Effect of high-intensity exercise and protein supplementation on muscle mass in ADL dependent older people with and without malnutrition — A randomized controlled trial
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Jyväkorpi, S. K., Puranen, T., and Suominen, M.
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- 2012
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12. Continuous pilot scale process demonstrating waste fibre as a feasible feedstock to ethanol and biogas production
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Kemppainen, Katariina, Ranta, L., Sipilä, E., Östman, A., Vehmaanperä, J., Puranen, T., Langfelder, K., Hannula, J., Kallioinen, Anne, Siika-aho, Matti, Sipilä, Kai, and von Weymarn, Niklas
- Abstract
Production processes for lignocellulosic bioethanol face challenges with increasing feedstock costs, high investment costs due to e.g. expensive pretreatment technologies and finding ideal ways to integrate the process to existing facilities. The FibreEtOH process was developed to tackle these challenges and run in pilot scale to demonstrate a profitable ethanol production process from waste fibre. The FibreEtOH process integrated to a pulp and paper mill consists of fractionation of solid recovered fuel, sanitation of the material by heat treatment, continuous liquefaction (prehydrolysis) of the waste fibre, simultaneous saccharification and fermentation of C6 sugars and biogas production from the fermented residue. Waste fibre fractionated from solid recovered fuel is a stable all-year-round feedstock with high hexose content (44-56%) and acceptable ash content (13-14%). Thermal or chemical pretreatment is not required for this material as experimental work showed reduction rather than improvement in hydrolysis yield and rate after pretreatment. Hydrolysis of glucan was found to be fast but recalcitrant mannose- and glucose-containing soluble oligo- and polysaccharides were produced that would require additional helper enzymes for hydrolysis to C6 sugars. The whole process from fractionation to biogas production was demonstrated in pilot-scale with promising results. Continuous runs in pilot-scale were operated for up to 12 days with efficient ethanol production and without major problems from bacterial contamination. The results presented here demonstrate the feasibility of the FibreEtOH concept as a potential production process for lignocellulosic bioethanol.
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- 2012
13. Characterization of two thermostable xylanases as accessory enzymes in lignocelluloses hydrolysis
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Zhang, J., Szijártó, N., Maijala, P., Siika-aho, Matti, Puranen, T., Tenkanen, Maija, and Viikari, Liisa
- Published
- 2010
14. Tailored nutritional guidance for home-dwelling AD families: The feasibility of and elements promoting positive changes in diet (NuAD-trial)
- Author
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Puranen, T. M., primary, Pitkala, K. H., additional, and Suominen, M. H., additional
- Published
- 2014
- Full Text
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15. Structure, function and engineering of thermostable GH-7 family cellobiohydrolases
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Koivula, Anu, Voutilainen, Sanni, Boer, Harry, Puranen, T., Siika-aho, Matti, Alapuranen, M., Viikari, Liisa, and Vehmaanperä, Jari
- Abstract
Cellulases are important industrial enzymes, which can be used e.g. in the pulp and paper, textile, and detergent industry. They are currently under intensive study particularly due to their applicability in total hydrolysis of cellulosic biomass for production of bioethanol and other chemicals. Thermostable enzymes are desirable for many cellulase applications, as they are generally robust, tolerating various harsh process conditions. Thermophilic organisms are a potential source for thermostable enzymes, or as an alternative the thermostability of an enzyme can be improved by structure-based rational mutagenesis or directed evolution methods. Glycosyl hydrolase family 7 (GH-7; see http://afmb.cnrs-mrs.fr/CAZY/citing.html) cellobiohydrolases seem to be especially important in the hydrolysis of highly crystalline cellulose, and are found only in the fungal kingdom. Here, we present the characterisation of the enzymatic properties of three novel thermostable cellobiohydrolases originating from the thermophililic fungi Acremonium thermophilum, Chaetomium thermophilum and Thermoascus aurantiacus. These GH-7 family enzymes were expressed in the industrially relevant production host Trichoderma reesei, and the kinetics on small soluble substrates, cellobiose inhibition, crystalline cellulose hydrolysis and thermostability of the purified enzymes were determined. Enzymatic properties of the cellobiohydrolases were compared to those of T.reesei cellobiohydrolase Cel7A, one of the most thoroughly studied fungal cellobiohydrolases. In addition, both random and site-directed mutagenesis approaches have been used to improve the performance of the Melanocarpus albomyces Cel7B at elevated temperatures. The biochemical results are also discussed from the structural point of view based on the three-dimensional structures and homology models of these enzymes. Acknowledgements: This work has been supported by grants from the EU ("Technological improvement for ethanol production from lignocellulose" project; coordinator L. Viikari, VTT), the Academy of Finland (SV) and the Finnish Glycoscience Graduate School (SV). References : [1] Voutilainen, S., Boer, H., Linder, M., Puranen, T., Rouvinen, J., Vehmaanperä, J. and Koivula, A. (2007) Heterologous expression and random mutagenesis to improve the thermostability of Melanocarpus albomyces Cel7B cellobiohydrolase. Enz. Microb. Technol. 41, 234-243. [2] Voutilainen, S., Puranen, T., Siika-aho, M., Lappalainen, A., Alapuranen, M., Kallio, J., Hooman, S., Viikari, L., Vehmaanperä, J. and Koivula, A. (2008) Cloning, expression and characterization of novel thermostable family 7 cellobiohydrolases. Biotechn. Bioeng.101, 515-528. [3] Parkkinen, T., Koivula, A., Vehmaanperä, J. and Rouvinen J. (2008) Crystal structure of Melanocarpus albomyces cellobiohydrolase Cel7B in complex with cello-oligomers show high flexibility in the substrate binding. Protein Sci. 17, 1383-1394. [4] Voutilainen, S., Boer, H., Alapuranen, M., Jänis, J., Vehmaanperä, J. and Koivula, A. (2008) Improving the thermostability and activity of Melanocarpus albomyces cellobiohydrolase Cel7B. - Submitted for publication.
- Published
- 2009
16. Characterization of novel thermostable fungal cellobiohydrolases
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Puranen, T., Voutilainen, Sanni, Siika-aho, Matti, Kallio, J., Hooman, Satu, Viikari, Liisa, Koivula, Anu, and Vehmaanperä, J.
- Abstract
Cellulose degradation requires sequential or simultaneous synergic action of three types of hydrolytic enzymes: cellobiohydrolases, endoglucanases and beta-glucosidases. Various filamentous fungi produce these enzymes in order to hydrolyze insoluble cellulose into glucose. Cellulases are currently extensively studied in enzyme industry for cellulosic biomass conversion to ethanol. Here, molecular cloning of three different cellobiohydrolase genes from thermophilic ascomycetes is presented together with their heterologous expression in Trichoderma reesei. The recombinant cellobiohydrolases that belong to the glycosyl hydrolase (GH) family 7 were purified and characterized in terms of pH optimum, thermal stability and kinetic parameters. Thermostable cellulases such as described here have been proposed to improve the overall process economy of the biomass conversion with favourable impact on enzyme need, hydrolysis performance and flexibility of the process.
- Published
- 2007
17. Characterization of fungal cellulases
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Voutilainen, Sanni, Puranen, T., Siika-aho, Matti, Alapuranen, M., Lappalainen, Arja, Hooman, S., Viikari, Liisa, Vehmaanperä, Jari, and Koivula, Anu
- Abstract
Cellulose is the most abundant polysaccharide on earth, found in nature almost exclusively in plant cell walls. Cellulose is a chemically simple molecule composed of linear homopolymers of D-glucose units linked by beta-1,4-glycosidic linkages and having a degree of polymerisation ranging from 100 up to 15,000. The smallest structural repeating unit in native cellulose is cellobiose, a disaccharide. This arrangement of glucose units leads to extended conformation of the cellulose chains which can pack together via inter- and intramolecular hydrogen bonds forming highly ordered crystalline fibers. Cellulases are a group of enzymes, secreted by micro-organisms living in plant litter and soil, and effectively degrading crystalline cellulose into soluble sugars in a concerted manner. Cellulases are also important industrial enzymes, which can be used e.g. in pulp and paper, textile, and detergent industry, as well as in conversion of cellulosic biomass to ethanol, a transport fuel. Thermostable enzymes are needed for many of these applications. Thermophilic organisms offer a potential source of thermostable enzymes for industrial applications, or alternatively thermostability of an enzyme can also be improved by structure-based rational mutagenesis or by directed evolution. Cellobiohydrolases are a class of cellulases especially active on crystalline cellulose hydrolysis. They degrade cellulose from the chain ends, producing mainly cellobiose (disaccharide) in a processive manner. Cellobiohydrolases are often modular enzymes consisting of a minimum of one catalytic module and one carbohydrate-binding module (CBM). The CBM is responsible for bringing the catalytic module near the substrate and improving the action on polymeric substrates while not affecting the activity on small soluble substrates. Results from the characterisation of enzymatic properties of three novel thermostable cellobiohydrolases belonging to the glycosyl hydrolase (GH) family 7 (http://afmb.cnrs-mrs.fr/CAZY/citing.html) will be presented. Acknowledgements: This study was part of an EU-project ¡§Technological improvement for ethanol production from lignocellulose (EU-TIME)¡¨.
- Published
- 2006
18. A comparative study of the enzymatic properties of thermostable fungal cellobiohydrolases from the GH family 7
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Voutilainen, Sanni, Puranen, T., Siika-aho, Matti, Alapuranen, M., Lappalainen, Arja, Hooman, S., Viikari, Liisa, Vehmaanperä, Jari, and Koivula, Anu
- Abstract
Cellulases are important industrial enzymes, which can be used e.g. in pulp and paper, textile, and detergent industry. Cellulases are also currently being studied and used to convert cellulose containing biomass to ethanol, a transport fuel. The enzymatic degradation of cellulosic biomass to soluble sugars is performed by consortium of enzymes acting in synergy. Despite of the published data available on the kinetic behaviour of various fungal and bacterial cellulases, systematic comparison studies on the enzymatic properties of different cellulases are still lacking. Comparable information would be needed to create a more thorough understanding of the function of these enzymes, and also for the application purposes, e.g. in finding the optimal enzyme mixtures for the total hydrolysis of cellulose. Here, we present results from screening of cellulase producing fungi, and the characterisation of enzymatic properties of the three most interesting thermostable cellobiohydrolases found from the screen. All three cellobiohydrolases belong to the glycosyl hydrolase (GH) family 7, and they were expressed in Trichoderma reesei before the purification and characterisation. Both the catalytic core modules and 2-module forms (composed of the catalytic and the cellulose-binding modules) of the cellobiohydrolases were included in the comparison. The enzymatic properties of these cellobiohydrolases were compared to those of the cellobiohydrolase Cel7A of T. reesei, which is among the most thoroughly studied fungal cellobiohydrolases. Acknowledgements: This study was part of EU-project: Technological improvement for ethanol production from lignocellulose (EU-TIME).
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- 2006
19. NUTRITIONAL INTERVENTION VIA VIDEOCONFERENCING FOR OLDER ADULTS RECEIVING HOME CARE - A PILOT STUDY
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PURANEN, T., primary, FINNE-SOVERI, H., additional, AURANNE, K., additional, LEHTINEN-FRASER, M., additional, and SUOMINEN, M.H., additional
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- 2013
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20. LB030-SUN BASELINE CHARACTERISTICS OF HOME-DWELLING AD PATIENTS AND THEIR SPOUSES PARTICIPATING IN A NUTRITIONAL TREATMENT RCT
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Jyväkorpi, S.K., primary, Puranen, T., additional, and Suominen, M.H., additional
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- 2012
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21. LB021-MON NUTRIENT INTAKE OF HOME DWELLING ALZHEIMER PATIENTS AND THEIR SPOUSES – GENDER PERSPECTIVE
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Puranen, T., primary, Jyvakorpi, S.K., additional, and Suominen, M.H., additional
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- 2012
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22. PP051-SUN HOW TO IMPROVE NUTRIENT INTAKE OF ALZHEIMER'S PATIENTS LIVING AT HOME WITH THEIR SPOUSES – QUALITATIVE DESCRIPTION OF TAILORED NUTRITIONAL ADVICE
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Puranen, T., primary, Jyvakorpi, S., additional, Eloniemi-Sulkava, U., additional, and Suominen, M., additional
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- 2012
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23. LB025-MON QUALITY OF LIFE, COGNITION AND PHYSICAL FUNCTIONING BETWEEN HIGHER AND LOWER INTAKES OF NUTRIENTS OF HOME-DWELLING OLDER AD PATIENTS
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Jyväkorpi, S., primary, Puranen, T., additional, and Suominen, M.H., additional
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- 2012
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24. Letter to the editor
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Jyväkorpi, S. K., primary, Puranen, T., additional, and Suominen, M., additional
- Published
- 2012
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25. PP042-MON NUTRITION OF HOME CARE CLIENTS
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Suominen, M., primary and Puranen, T., additional
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- 2011
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26. Calcium intake of service house residents - when are supplements needed?
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Suominen, M. H., Vikstedt, T., Puranen, T. M., Muurinen, S., Soini, H., and Pitkala, K. H.
- Abstract
Purpose Calcium has beneficial effects in preventing osteoporosis and fractures among older adults but supplements may have adverse effects if calcium accumulates in the arteries. Aim was to examine total calcium intake from food and supplements of older residents in service houses and assess whether the use of supplements was directed appropriately. Subjects and methods Residents in service houses in the metropolitan region of Helsinki, Finland. Residents' calcium intake was calculated from one-day food diaries. Use of calcium supplements was retrieved from medical records. Results In total, 350 service house residents participated. Their mean age was 83 years; 82% were females. According to the MNA, 21% suffered from malnutrition. The mean dietary calcium intake of females was 1113mg per day. Including food and supplements, their mean intake was 1441mg. The corresponding figures for males were 1224mg and 1528mg. Of all residents, 13% had a total daily calcium intake from food and supplements that was<800mg, 29% 800-1200mg, and 59%>1200mg. More than one-third (37%) of the residents used calcium supplements daily. Of those having calcium intake from food<800mg, only 32% were administered calcium supplements. The respective proportions among groups in which calcium intake from food was 800-1200mg, 1200-1500mg, or>1500mg were 37%, 43%, and 36%. Conclusions Dietary intake of calcium should be evaluated and administration of calcium supplements should be directed to those whose intake of calcium from food is low. [ABSTRACT FROM AUTHOR]
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- 2014
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27. TYPE 1 17-BETA HYDROXYSTEROID DEHYDROGENASE EQUILIN COMPLEXED WITH NADP+
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Sawicki, M.W., primary, Erman, M., additional, Puranen, T., additional, Vihko, P., additional, and Ghosh, D., additional
- Published
- 1999
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28. Characterization of Structural and Functional Properties of Human 17 -Hydroxysteroid Dehydrogenase Type 1 Using Recombinant Enzymes and Site-Directed Mutagenesis
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Puranen, T., primary
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- 1997
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29. Site-directed mutagenesis of the putative active site of human 17β-hydroxysteroid dehydrogenase type 1
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Puranen, T J, primary, Poutanen, M H, additional, Peltoketo, H E, additional, Vihko, P T, additional, and Vihko, R K, additional
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- 1994
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30. Correction: Relationship between oral frailty, health-related quality of life, and survival among long-term care residents.
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Puranen T, Hiltunen K, Kautiainen H, Suominen MH, Salminen K, Mäntylä P, Roitto HM, Pitkälä KH, and Saarela RKT
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- 2023
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31. Relationship between oral frailty, health-related quality of life, and survival among long-term care residents.
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Puranen T, Hiltunen K, Kautiainen H, Suominen MH, Salminen K, Mäntylä P, Roitto HM, Pitkälä KH, and Saarela RKT
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- Aged, 80 and over, Female, Humans, Male, Cross-Sectional Studies, Nursing Homes, Frailty diagnosis, Long-Term Care methods, Long-Term Care psychology, Quality of Life
- Abstract
Purpose: We evaluated oral frailty (OFr) and its association with health-related quality of life (HRQoL), energy and protein intake, and survival among older long-term care residents., Methods: This cross-sectional study with a 3-year follow-up for survival assessed 349 residents in long-term care facilities (73% female, mean age 82 years). We defined OFr with six signs (dry mouth, food residue on oral surfaces, unclear speech, inability to keep mouth open or pain expression during the clinical oral examination, diet pureed/soft) and OFr severity was categorized as Group 1, (mild) = 0-1 signs, Group 2 (moderate) = 2-4 signs, and Group 3 (severe) = 5-6 signs. We measured HRQoL with 15D instrument, and energy and protein intake by a 1- to 2-day food record. Mortality was retrieved from central registers on March 2021., Results: Of the residents, 15% had 0-1, 67% 2-4 and 18% 5-6 OFr signs. HRQoL decreased linearly from Group 1 to Group 3. OFr correlated with such dimensions of HRQoL as mobility, eating, speech, excretion, usual activities, mental function, and vitality. We found no association between OFr categories and energy and protein intake. Survival decreased linearly from Group 1 to Group 3., Conclusions: OFr was common among older long-term care residents and OFr severity predicts poorer outcomes. The six oral signs denoting OFr may be used at the bedside to screen residents at risk for OFr., (© 2023. The Author(s).)
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- 2023
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32. UV-visible absorption spectroscopy for in-line API concentration measurement in nanoparticle production process using controlled expansion of supercritical solutions (CESS®).
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Kauppinen A, Helander P, Viitala M, Puranen T, Vainikka T, Lassila I, Hæggström E, and Sandler N
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- Pharmaceutical Preparations chemistry, Spectrum Analysis, Temperature, Solubility, Nanoparticles chemistry
- Abstract
Most new small drug molecules in pharmaceutical development require improvement of solubility. The controlled expansion of supercritical solutions (CESS®) process is a nanoparticle production technology, dedicated to enhancing the dissolution rate of active pharmaceutical ingredients (APIs) suffering from poor solubility and enabling novel drug delivery opportunities. In this process, the API is dissolved in supercritical carbon dioxide (scCO
2 ) and nanoparticles are formed through controlled pressure reduction. To improve process visibility and control, ultraviolet-visible (UV-Vis) spectroscopy was incorporated into CESS® process as a process analytical technology (PAT) tool. The tool quantifies the amount of API dissolved in scCO2 during the solubilization phase of the process. Sample interfacing of the UV-Vis spectrometer was done with a custom-made pressure and temperature rated transmission flow-through cell. In-process calibration was developed to correlate the UV-Vis absorption spectra to the API concentration. Due to the density-dependent molar absorption coefficient of API in scCO2 , the calibration was done for each combination of temperature and pressure. The developed PAT tool provides insight into the process enabling real-time API quantity estimation. It also facilitates process development through Quality by Design (QbD) and offers a system for enhanced process control and troubleshooting. For instance, the in-line API concentration data allows one to study the solubilization behavior of the API in the process and to optimize the process parameters in order to maximize throughput., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ari Kauppinen reports a relationship with Nanoform Finland Plc that includes: employment. Petteri Helander reports a relationship with Nanoform Finland Plc that includes: employment. Mikael Viitala reports a relationship with Nanoform Finland Plc that includes: employment. Tuomas Puranen reports a relationship with Nanoform Finland Plc that includes: employment. Tuomas Vainikka reports a relationship with Nanoform Finland Plc that includes: employment. Ilkka Lassila reports a relationship with Nanoform Finland Plc that includes: employment and equity or stocks. Edward Hæggström reports a relationship with Nanoform Finland Plc that includes: employment and equity or stocks. Niklas Sandler reports a relationship with Nanoform Finland Plc that includes: employment and equity or stocks. Edward Hæggström has patent A method and a device for producing nanoparticles issued to Nanoform Finland Oy. Ilkka Lassila has patent A method and a device for producing nanoparticles issued to Nanoform Finland Oy., (Copyright © 2022 Elsevier B.V. All rights reserved.)- Published
- 2023
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33. Ultrasonic actuation of a fine-needle improves biopsy yield.
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Perra E, Lampsijärvi E, Barreto G, Arif M, Puranen T, Hæggström E, Pritzker KPH, and Nieminen HJ
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- Animals, Biopsy, Fine-Needle instrumentation, Biopsy, Fine-Needle methods, Cattle, Drug Delivery Systems instrumentation, Drug Delivery Systems methods, Gene Transfer Techniques instrumentation, Humans, Minimally Invasive Surgical Procedures instrumentation, Minimally Invasive Surgical Procedures methods, Phantoms, Imaging, Surgery, Computer-Assisted instrumentation, Surgery, Computer-Assisted methods, Ultrasonics instrumentation, Ultrasonics methods, Needles, Ultrasonography, Interventional instrumentation, Ultrasonography, Interventional methods
- Abstract
Despite the ubiquitous use over the past 150 years, the functions of the current medical needle are facilitated only by mechanical shear and cutting by the needle tip, i.e. the lancet. In this study, we demonstrate how nonlinear ultrasonics (NLU) extends the functionality of the medical needle far beyond its present capability. The NLU actions were found to be localized to the proximity of the needle tip, the SonoLancet, but the effects extend to several millimeters from the physical needle boundary. The observed nonlinear phenomena, transient cavitation, fluid streams, translation of micro- and nanoparticles and atomization, were quantitatively characterized. In the fine-needle biopsy application, the SonoLancet contributed to obtaining tissue cores with an increase in tissue yield by 3-6× in different tissue types compared to conventional needle biopsy technique using the same 21G needle. In conclusion, the SonoLancet could be of interest to several other medical applications, including drug or gene delivery, cell modulation, and minimally invasive surgical procedures.
- Published
- 2021
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34. Controlling oleogel crystallization using ultrasonic standing waves.
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Valoppi F, Salmi A, Ratilainen M, Barba L, Puranen T, Tommiska O, Helander P, Heikkilä J, and Haeggström E
- Abstract
Oleogels are lipid-based soft materials composed of large fractions of oil (> 85%) developed as saturated and hydrogenated fat substitutes to reduce cardiovascular diseases caused by obesity. Promising oleogels are unstable during storage, and to improve their stability careful control of the crystalline network is necessary. However, this is unattainable with state-of-the-art technologies. We employ ultrasonic standing wave (USSW) fields to modify oleogel structure. During crystallization, the growing crystals move towards the US-SW nodal planes. Homogeneous, dense bands of microcrystals form independently of oleogelator type, concentration, and cooling rate. The thickness of these bands is proportional to the USSW wavelength. These new structures act as physical barriers in reducing the migration kinetics of a liposoluble colorant compared to statically crystallized oleogels. These results may extend beyond oleogels to potentially be used wherever careful control of the crystallization process and final structure of a system is needed, such as in the cosmetics, pharmaceutical, chemical, and food industries.
- Published
- 2020
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35. Practical realization of a sub-λ/2 acoustic jet.
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Veira Canle D, Kekkonen T, Mäkinen J, Puranen T, Nieminen HJ, Kuronen A, Franssila S, Kotiaho T, Salmi A, and Hæggström E
- Abstract
Studies in optics and acoustics have employed metamaterial lenses to achieve sub-wavelength localization, e.g. a recently introduced concept called 'acoustojet' which in simulations localizes acoustic energy to a spot smaller than λ/2. However previous experimental results on the acoustojet have barely reached λ/2-wide localization. Here we show, by simulations and experiments, that a sub-λ/2 wide localization can be achieved by translating the concept of a photonic jet into the acoustic realm. We performed nano- to macroscale molecular dynamics (MD) and finite element method (FEM) simulations as well as macroscale experiments. We demonstrated that by choosing a suitable size cylindrical lens, and by selecting the speed-of-sound ratio between the lens material(s) and the surrounding medium, an acoustic jet ('acoustic sheet') is formed with a full width at half maximum (FWHM) less than λ/2. The results show, that the acoustojet approach can be experimentally realized with easy-to-manufacture acoustic lenses at the macroscale. MD simulations demonstrate that the concept can be extended to coherent phonons at nanoscale. Finally, our FEM simulations identify some micrometer size structures that could be realized in practice. Our results may contribute to starting a new era of super resolution acoustic imaging: We foresee that jet generating constructs can be readily manufactured, since suitable material combinations can be found from nanoscale to macroscale. Tight focusing of mechanical energy is highly desirable in e.g. electronics, materials science, medicine, biosciences, and energy harvesting.
- Published
- 2019
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36. High proportions of older people with normal nutritional status have poor protein intake and low diet quality.
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Jyväkorpi SK, Pitkälä KH, Puranen TM, Björkman MP, Kautiainen H, Strandberg TE, Soini HH, and Suominen MH
- Subjects
- Aged, Aged, 80 and over, Assisted Living Facilities, Cross-Sectional Studies, Female, Humans, Independent Living, Male, ROC Curve, Sensitivity and Specificity, Diet, Dietary Proteins, Energy Intake, Malnutrition diagnosis, Nutrition Assessment, Nutritional Status
- Abstract
Introduction: The Mini Nutritional Assessment (MNA) is a well-validated instrument examining the nutritional status of older people. The aim of this study was to examine how older people's energy and nutrient intakes are associated with the MNA and to determine how sensitive and specific MNA is in identifying those having low energy and protein intakes., Materials and Methods: This cross-sectional study combined data from five nutritional studies (N=900): both home-dwelling and institutionalized older people without and with disabilities. Their nutritional status was assessed with MNA, and nutrient intakes were retrieved from 1 to 3day food diaries. Nutrient intakes were divided according to MNA status (normal nutritional status, at-risk of malnutrition, malnourished). Sensitivity, specificity, and likelihood ratios of MNA of various cut-off points were tested with recommended protein and energy intakes. ROC curves was constructed., Results: Energy, protein and most nutrient intakes showed logical linear trends according to MNA classes. However, more than three-fourths of the participants with MNA>23.5 had lower than recommended protein intakes. Sensitivity of MNA ranged from 0.32 to 0.82 for recommended energy (F:1570kcal/d/M:2070kcal/d) and protein intakes (1.0g/kg BW or 1.2g/kgBW) cut-off points, and specificity from 0.75 to 0.25, respectively. AUC values were low (0.52-0.53)., Conclusions: MNA status was consistently associated with nutrient intakes and diet quality. However, a high proportion of older people even with normal nutritional status had poor energy and protein intakes. Thus, MNA does not identify all those with poor nutrient intakes who may be at risk of developing malnutrition., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2016
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37. Low protein and micronutrient intakes in heterogeneous older population samples.
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Jyväkorpi SK, Pitkälä KH, Puranen TM, Björkman MP, Kautiainen H, Strandberg TE, Soini H, and Suominen MH
- Subjects
- Aged, Aged, 80 and over, Cross-Sectional Studies, Feeding Behavior, Female, Finland epidemiology, Folic Acid, Humans, Male, Nutrition Assessment, Population Surveillance, Prevalence, Energy Intake, Malnutrition epidemiology, Micronutrients administration & dosage, Nutritional Status
- Abstract
Background: Malnutrition is associated with comorbidities and functional decline among older people. Less is known about nutrient intakes across heterogeneous older populations., Objective: We examined nutritional status and nutrient intakes in different samples of older people representing broad spectrum of healthy and frail populations. We evaluated adequacy of their energy, protein and micronutrient intakes in comparison to recommendations., Design and Participants: Cross-sectional study combined five datasets: home-dwelling older people participating in nutrition education and cooking classes (NC) [n=54], participants from Helsinki Businessmen Study [n=68], home-dwelling people with Alzheimer disease (AD) [n=99] and their spousal caregivers (n=97), participants from Porvoo Sarcopenia and Nutrition Trial (n=208), and residents of Helsinki assisted living facilities (ALF) [n=374]. Nutritional status was assessed using Mini Nutritional Assessment and nutrient intakes retrieved from 1 to 3 day food records., Results: Those suffering most from mobility limitation and cognitive decline had the poorest nutritional status (p<0.001; adjusted for age, sex, comorbidities). However, low intakes of energy, protein, and micronutrients were observed in high proportion in all groups, inadequate intakes of vitamins D, E, folate, and thiamine being most common. Protein intakes did not differ between the groups, but 77% of all participants had lower than recommended protein intake. In general, the NC group had highest micronutrient intakes and the ALF group the lowest. However, AD females had the lowest energy, protein, and vitamin C intakes., Conclusions: Our study provides a detailed picture of risks related to nutrient intakes in various groups of older people. These findings could be used in planning tailored nutrition interventions., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2015
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38. Mixtures of thermostable enzymes show high performance in biomass saccharification.
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Kallioinen A, Puranen T, and Siika-aho M
- Subjects
- Cellulose chemistry, Cellulose metabolism, Enzyme Stability, Hydrolysis, Lignin chemistry, Oxidation-Reduction, Saccharum chemistry, Statistics as Topic, Steam, Trichoderma enzymology, Triticum chemistry, Biomass, Glycoside Hydrolases metabolism, Lignin metabolism, Temperature
- Abstract
Optimal enzyme mixtures of six Trichoderma reesei enzymes and five thermostable enzyme components were developed for the hydrolysis of hydrothermally pretreated wheat straw, alkaline oxidised sugar cane bagasse and steam-exploded bagasse by statistically designed experiments. Preliminary studies to narrow down the optimization parameters showed that a cellobiohydrolase/endoglucanase (CBH/EG) ratio of 4:1 or higher of thermostable enzymes gave the maximal CBH-EG synergy in the hydrolysis of hydrothermally pretreated wheat straw. The composition of optimal enzyme mixtures depended clearly on the substrate and on the enzyme system studied. The optimal enzyme mixture of thermostable enzymes was dominated by Cel7A and required a relatively high amount of xylanase, whereas with T. reesei enzymes, the high proportion of Cel7B appeared to provide the required xylanase activity. The main effect of the pretreatment method was that the required proportion of xylanase was higher and the proportion of Cel7A lower in the optimized mixture for hydrolysis of alkaline oxidised bagasse than steam-exploded bagasse. In prolonged hydrolyses, less Cel7A was generally required in the optimal mixture. Five-component mixtures of thermostable enzymes showed comparable hydrolysis yields to those of commercial enzyme mixtures.
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- 2014
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39. Cellulases without carbohydrate-binding modules in high consistency ethanol production process.
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Pakarinen A, Haven MO, Djajadi DT, Várnai A, Puranen T, and Viikari L
- Abstract
Background: Enzymes still comprise a major part of ethanol production costs from lignocellulose raw materials. Irreversible binding of enzymes to the residual substrate prevents their reuse and no efficient methods for recycling of enzymes have so far been presented. Cellulases without a carbohydrate-binding module (CBM) have been found to act efficiently at high substrate consistencies and to remain non-bound after the hydrolysis., Results: High hydrolysis yields could be obtained with thermostable enzymes of Thermoascus aurantiacus containing only two main cellulases: cellobiohydrolase I (CBH I), Cel7A and endoglucanase II (EG II), Cel5A. The yields were decreased by only about 10% when using these cellulases without CBM. A major part of enzymes lacking CBM was non-bound during the most active stage of hydrolysis and in spite of this, produced high sugar yields. Complementation of the two cellulases lacking CBM with CBH II (CtCel6A) improved the hydrolysis. Cellulases without CBM were more sensitive during exposure to high ethanol concentration than the enzymes containing CBM. Enzymes lacking CBM could be efficiently reused leading to a sugar yield of 90% of that with fresh enzymes. The applicability of cellulases without CBM was confirmed under industrial ethanol production conditions at high (25% dry matter (DM)) consistency., Conclusions: The results clearly show that cellulases without CBM can be successfully used in the hydrolysis of lignocellulose at high consistency, and that this approach could provide new means for better recyclability of enzymes. This paper provides new insight into the efficient action of CBM-lacking cellulases. The relationship of binding and action of cellulases without CBM at high DM consistency should, however, be studied in more detail.
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- 2014
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40. Cellulase-lignin interactions-the role of carbohydrate-binding module and pH in non-productive binding.
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Rahikainen JL, Evans JD, Mikander S, Kalliola A, Puranen T, Tamminen T, Marjamaa K, and Kruus K
- Subjects
- Adsorption, Catalytic Domain genetics, Cellulase genetics, Cellulose metabolism, Hydrogen-Ion Concentration, Hydrolysis, Hydrophobic and Hydrophilic Interactions, Lignin chemistry, Models, Molecular, Mutagenesis, Site-Directed, Recombinant Proteins chemistry, Recombinant Proteins genetics, Recombinant Proteins metabolism, Sordariales enzymology, Sordariales genetics, Static Electricity, Trichoderma enzymology, Trichoderma genetics, Cellulase chemistry, Cellulase metabolism, Lignin metabolism
- Abstract
Non-productive cellulase adsorption onto lignin is a major inhibitory mechanism preventing enzymatic hydrolysis of lignocellulosic feedstocks. Therefore, understanding of enzyme-lignin interactions is essential for the development of enzyme mixtures and processes for lignocellulose hydrolysis. We have studied cellulase-lignin interactions using model enzymes, Melanocarpus albomyces Cel45A endoglucanase (MaCel45A) and its fusions with native and mutated carbohydrate-binding modules (CBMs) from Trichoderma reesei Cel7A. Binding of MaCel45A to lignin was dependent on pH in the presence and absence of the CBM; at high pH, less enzyme bound to isolated lignins. Potentiometric titration of the lignin preparations showed that negatively charged groups were present in the lignin samples and that negative charge in the samples was increased with increasing pH. The results suggest that electrostatic interactions contributed to non-productive enzyme adsorption: Reduced enzyme binding at high pH was presumably due to repulsive electrostatic interactions between the enzymes and lignin. The CBM increased binding of MaCel45A to the isolated lignins only at high pH. Hydrophobic interactions are probably involved in CBM binding to lignin, because the same aromatic amino acids that are essential in CBM-cellulose interaction were also shown to contribute to lignin-binding., (Copyright © 2013 Elsevier Inc. All rights reserved.)
- Published
- 2013
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41. The role of carbohydrate binding module (CBM) at high substrate consistency: comparison of Trichoderma reesei and Thermoascus aurantiacus Cel7A (CBHI) and Cel5A (EGII).
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Le Costaouëc T, Pakarinen A, Várnai A, Puranen T, and Viikari L
- Subjects
- Adsorption, Hydrolysis, Substrate Specificity, Bacterial Proteins metabolism, Carbohydrate Metabolism, Thermoascus metabolism, Trichoderma metabolism
- Abstract
The role of CBM in two fungal model cellulase systems, consisting of Cel7A and Cel5A, from Trichoderma reesei and Thermoascus aurantiacus, were compared in the hydrolysis of various substrates. For comparison, family-1 CBM's were introduced to the T. aurantiacus and removed from the T. reesei enzymes. Especially at high dry matter consistencies of lignocellulosic substrates, pretreated wheat straw and spruce, the T. aurantiacus enzymes lacking CBM outperformed the enzymes carrying the CBM. In these conditions, the CBM-less enzymes from both organisms obviously recognized and bound to the substrate at higher probability than in dilute systems. Avoiding the unproductive binding to lignin caused by the CBMs obviously enhanced the hydrolytic performance. The lignin binding effect was, however, not entirely caused by the CBM, but also by the different structures and affinities of the core enzymes to lignin. Due to decreased binding, the CBM-less enzymes would allow reuse, potentially decreasing hydrolysis costs., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2013
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42. Nutritional treatment of aged individuals with Alzheimer disease living at home with their spouses: study protocol for a randomized controlled trial.
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Jyvakorpi SK, Puranen T, Pitkala KH, and Suominen MH
- Subjects
- Aged, Alzheimer Disease complications, Alzheimer Disease diagnosis, Alzheimer Disease physiopathology, Alzheimer Disease psychology, Body Weight, Cognition, Counseling, Depression etiology, Dietary Supplements, Finland, Geriatric Assessment, Hand Strength, Humans, Malnutrition diagnosis, Malnutrition etiology, Malnutrition physiopathology, Malnutrition psychology, Nutrition Assessment, Quality of Life, Time Factors, Treatment Outcome, Vitamin D therapeutic use, Vitamins therapeutic use, Alzheimer Disease therapy, Caregivers psychology, Independent Living, Malnutrition prevention & control, Nutrition Therapy, Nutritional Status, Research Design, Spouses psychology
- Abstract
Background: Nutritional status often deteriorates in Alzheimer's disease (AD). Less is known about whether nutritional care reverses malnutrition and its harmful consequences in AD. The aim of this study is to examine whether individualized nutritional care has an effect on weight, nutrition, health, physical functioning, and quality of life in older individuals with AD and their spouses living at home., Methods: AD patients and their spouses (aged > 65 years) living at home (n = 202, 102 AD patients) were recruited using central AD registers in Finland. The couples were randomized into intervention and control groups. A trained nutritionist visited intervention couples 4-8 times at their homes and the couples received tailored nutritional care. When necessary, the couples were given protein and nutrient-enriched complementary drinks. All intervention couples were advised to take vitamin D 20 μg/day. The intervention lasted for one year. The couples of the control group received a written guide on nutrition of older people. Participants in the intervention group were assessed every three months. The primary outcome measure is weight change. Secondary measures are the intake of energy, protein, and other nutrients, nutritional status, cognition, caregiver's burden, depression, health related quality of life and grip strength., Discussion: This study provides data on whether tailored nutritional care is beneficial to home-dwelling AD patients and their spouses., Trial Registration: ACTRN 12611000018910.
- Published
- 2012
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43. Thermostable recombinant xylanases from Nonomuraea flexuosa and Thermoascus aurantiacus show distinct properties in the hydrolysis of xylans and pretreated wheat straw.
- Author
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Zhang J, Siika-Aho M, Puranen T, Tang M, Tenkanen M, and Viikari L
- Abstract
Background: In the hydrolysis of lignocellulosic materials, thermostable enzymes decrease the amount of enzyme needed due to higher specific activity and elongate the hydrolysis time due to improved stability. For cost-efficient use of enzymes in large-scale industrial applications, high-level expression of enzymes in recombinant hosts is usually a prerequisite. The main aim of the present study was to compare the biochemical and hydrolytic properties of two thermostable recombinant glycosyl hydrolase families 10 and 11 (GH10 and GH11, respectively) xylanases with respect to their potential application in the hydrolysis of lignocellulosic substrates., Results: The xylanases from Nonomuraea flexuosa (Nf Xyn11A) and from Thermoascus aurantiacus (Ta Xyn10A) were purified by heat treatment and gel permeation chromatography. Ta Xyn10A exhibited higher hydrolytic efficiency than Nf Xyn11A toward birchwood glucuronoxylan, insoluble oat spelt arabinoxylan and hydrothermally pretreated wheat straw, and it produced more reducing sugars. Oligosaccharides from xylobiose to xylopentaose as well as higher degree of polymerization (DP) xylooligosaccharides (XOSs), but not xylose, were released during the initial hydrolysis of xylans by Nf Xyn11A, indicating its potential for the production of XOS. The mode of action of Nf Xyn11A and Ta Xyn10A on glucuronoxylan and arabinoxylan showed typical production patterns of endoxylanases belonging to GH11 and GH10, respectively., Conclusions: Because of its high catalytic activity and good thermostability, T. aurantiacus xylanase shows great potential for applications aimed at total hydrolysis of lignocellulosic materials for platform sugars, whereas N. flexuosa xylanase shows more significant potential for the production of XOSs.
- Published
- 2011
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44. Thermostable endoglucanases in the liquefaction of hydrothermally pretreated wheat straw.
- Author
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Szijártó N, Horan E, Zhang J, Puranen T, Siika-Aho M, and Viikari L
- Abstract
Background: Thermostable enzymes have several benefits in lignocellulose processing. In particular, they potentially allow the use of increased substrate concentrations (because the substrate viscosity decreases as the temperature increases), resulting in improved product yields and reduced capital and processing costs. A short pre-hydrolysis step at an elevated temperature using thermostable enzymes aimed at rapid liquefaction of the feedstock is seen as an attractive way to overcome the technical problems (such as poor mixing and mass transfer properties) connected with high initial solid loadings in the lignocellulose to ethanol process., Results: The capability of novel thermostable enzymes to reduce the viscosity of high-solid biomass suspensions using a real-time viscometric measurement method was investigated. Heterologously expressed enzymes from various thermophilic organisms were compared for their ability to liquefy the lignocellulosic substrate, hydrothermally pretreated wheat straw. Once the best enzymes were identified, the optimal temperatures for these enzymes to decrease substrate viscosity were compared. The combined hydrolytic properties of the thermostable preparations were tested in hydrolysis experiments. The studied mixtures were primarily designed to have good liquefaction potential, and therefore contained an enhanced proportion of the key liquefying enzyme, EGII/Cel5A., Conclusions: Endoglucanases were shown to have a superior ability to rapidly reduce the viscosity of the 15% (w/w; dry matter) hydrothermally pretreated wheat straw. Based on temperature profiling studies, Thermoascus aurantiacus EGII/Cel5A was the most promising enzyme for biomass liquefaction. Even though they were not optimized for saccharification, many of the thermostable enzyme mixtures had superior hydrolytic properties compared with the commercial reference enzymes at 55°C.
- Published
- 2011
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45. Cloning, expression, and characterization of novel thermostable family 7 cellobiohydrolases.
- Author
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Voutilainen SP, Puranen T, Siika-Aho M, Lappalainen A, Alapuranen M, Kallio J, Hooman S, Viikari L, Vehmaanperä J, and Koivula A
- Subjects
- Binding Sites, Cellobiose pharmacology, Cellulose metabolism, Cellulose 1,4-beta-Cellobiosidase chemistry, Cloning, Molecular, Enzyme Inhibitors pharmacology, Enzyme Stability, Models, Molecular, Protein Structure, Tertiary, Recombinant Proteins chemistry, Recombinant Proteins genetics, Recombinant Proteins metabolism, Trichoderma enzymology, Acremonium enzymology, Cellulose 1,4-beta-Cellobiosidase genetics, Cellulose 1,4-beta-Cellobiosidase metabolism, Chaetomium enzymology, Eurotiales enzymology, Hot Temperature
- Abstract
As part of the effort to find better cellulases for bioethanol production processes, we were looking for novel GH-7 family cellobiohydrolases, which would be particularly active on insoluble polymeric substrates and participate in the rate-limiting step in the hydrolysis of cellulose. The enzymatic properties were studied and are reported here for family 7 cellobiohydrolases from the thermophilic fungi Acremonium thermophilum, Thermoascus aurantiacus, and Chaetomium thermophilum. The Trichoderma reesei Cel7A enzyme was used as a reference in the experiments. As the native T. aurantiacus Cel7A has no carbohydrate-binding module (CBM), recombinant proteins having the CBM from either the C. thermophilum Cel7A or the T. reesei Cel7A were also constructed. All these novel acidic cellobiohydrolases were more thermostable (by 4-10 degrees C) and more active (two- to fourfold) in hydrolysis of microcrystalline cellulose (Avicel) at 45 degrees C than T. reesei Cel7A. The C. thermophilum Cel7A showed the highest specific activity and temperature optimum when measured on soluble substrates. The most effective enzyme for Avicel hydrolysis at 70 degrees C, however, was the 2-module version of the T. aurantiacus Cel7A, which was also relatively weakly inhibited by cellobiose. These results are discussed from the structural point of view based on the three-dimensional homology models of these enzymes., ((c) 2008 Wiley Periodicals, Inc.)
- Published
- 2008
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46. Increased production of xylanase by expression of a truncated version of the xyn11A gene from Nonomuraea flexuosa in Trichoderma reesei.
- Author
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Paloheimo M, Mäntylä A, Kallio J, Puranen T, and Suominen P
- Subjects
- Actinomycetales genetics, Endo-1,4-beta Xylanases genetics, Gene Expression, Genes, Bacterial, Protein Folding, Protein Sorting Signals, Protein Structure, Tertiary genetics, RNA, Messenger biosynthesis, RNA, Messenger genetics, Recombinant Fusion Proteins biosynthesis, Recombinant Fusion Proteins genetics, Recombinant Proteins genetics, Xylans metabolism, Actinomycetales enzymology, Endo-1,4-beta Xylanases biosynthesis, Recombinant Proteins biosynthesis, Sequence Deletion, Trichoderma genetics, Trichoderma metabolism
- Abstract
We have previously shown that the Nonomuraea flexuosa Xyn11A polypeptides devoid of the carbohydrate binding module (CBM) have better thermostability than the full-length xylanase and are effective in bleaching of pulp. To produce an enzyme preparation useful for industrial applications requiring high temperature, the region encoding the CBM was deleted from the N. flexuosa xyn11A gene and the truncated gene was expressed in Trichoderma reesei. The xylanase sequence was fused to the T. reesei mannanase I (Man5A) signal sequence or 3' to a T. reesei carrier polypeptide, either the Man5A core/hinge or the cellulose binding domain (CBD) of cellobiohydrolase II (Cel6A, CBHII). The gene and fusion genes were expressed using the cellobiohydrolase 1 (cel7A, cbh1) promoter. Single-copy isogenic transformants in which the expression cassette replaced the cel7A gene were cultivated and analyzed. The transformants expressing the truncated N. flexuosa xyn11A produced clearly increased amounts of both the xylanase/fusion mRNA and xylanase activity compared to the corresponding strains expressing the full-length N. flexuosa xyn11A. The transformant expressing the cel6A CBD-truncated N. flexuosa xyn11A produced about 1.9 g liter-1 of the xylanase in laboratory-scale fermentations. The xylanase constituted about 25% of the secreted proteins. The production of the truncated xylanase did not induce the unfolded protein response (UPR) pathway. However, the UPR was induced when the full-length N. flexuosa xyn11A with an exact fusion to the cel7A terminator was expressed. We suggest that the T. reesei folding/secretion machinery is not able to cope properly with the bacterial CBM when the mRNA of the full-length N. flexuosa xyn11A is efficiently translated.
- Published
- 2007
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47. Characterization of the bga1-encoded glycoside hydrolase family 35 beta-galactosidase of Hypocrea jecorina with galacto-beta-D-galactanase activity.
- Author
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Gamauf C, Marchetti M, Kallio J, Puranen T, Vehmaanperä J, Allmaier G, Kubicek CP, and Seiboth B
- Subjects
- Catalysis, Disaccharides chemistry, Disaccharides metabolism, Enzyme Stability, Fungal Proteins isolation & purification, Fungal Proteins metabolism, Galactans chemistry, Galactans metabolism, Galactose analogs & derivatives, Galactose chemistry, Galactose metabolism, Glycoproteins chemistry, Glycoproteins metabolism, Glycoside Hydrolases metabolism, Glycosylation, Hydrogen-Ion Concentration, Hypocrea chemistry, Kinetics, Lactose chemistry, Lactose metabolism, Lactulose chemistry, Lactulose metabolism, Molecular Weight, Nitrophenylgalactosides chemistry, Nitrophenylgalactosides metabolism, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Substrate Specificity, Temperature, beta-Galactosidase isolation & purification, beta-Galactosidase metabolism, Fungal Proteins chemistry, Glycoside Hydrolases chemistry, Hypocrea enzymology, beta-Galactosidase chemistry
- Abstract
The extracellular bga1-encoded beta-galactosidase of Hypocrea jecorina (Trichoderma reesei) was overexpressed under the pyruvat kinase (pki1) promoter region and purified to apparent homogeneity. The monomeric enzyme is a glycoprotein with a molecular mass of 118.8 +/- 0.5 kDa (MALDI-MS) and an isoelectric point of 6.6. Bga1 is active with several disaccharides, e.g. lactose, lactulose and galactobiose, as well as with aryl- and alkyl-beta-D-galactosides. Based on the catalytic efficiencies, lactitol and lactobionic acid are the poorest substrates and o-nitrophenyl-beta-D-galactoside and lactulose are the best. The pH optimum for the hydrolysis of galactosides is approximately 5.0, and the optimum temperature was found to be 60 degrees C. Bga1 is also capable of releasing D-galactose from beta-galactans and is thus actually a galacto-beta-D-galactanase. beta-Galactosidase is inhibited by its reaction product D-galactose and the enzyme also shows a significant transferase activity which results in the formation of galacto-oligosaccharides.
- Published
- 2007
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48. Thermoascus aurantiacus CBHI/Cel7A production in Trichoderma reesei on alternative carbon sources.
- Author
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Benko Z, Drahos E, Szengyel Z, Puranen T, Vehmaanperä J, and Réczey K
- Subjects
- Genetic Enhancement methods, Lactose metabolism, Protein Engineering methods, Ascomycota genetics, Ascomycota metabolism, Carbon Compounds, Inorganic metabolism, Cellulose 1,4-beta-Cellobiosidase genetics, Cellulose 1,4-beta-Cellobiosidase metabolism, Trichoderma genetics, Trichoderma metabolism, Zea mays microbiology
- Abstract
To develop functional enzymes in cellulose hydrolysis at or above 70 degrees C the cellobiohydrolase (CBHI/Cel7A) of Thermoascus aurantiacus was cloned and expressed in Trichoderma reesei Rut-C30 under the strong cbh1 promoter. Cellulase production of the parental strain and the novel strain (RF6026) was examined in submerged fermentation experiments using various carbon sources, which were lactose, Solka Floc 200 cellulose powder, and steam pretreated corn stover. An industrially feasible production medium was used containing only distiller's spent grain, KH(2)PO(4), and (NH(4))(2)SO(4). Enzyme production was followed by measurements of protein concentration, total cellulase enzyme activity (filter paper activity), beta-glucosidase activity, CBHI activity, and endogenase I (EGI) activity. The Thermoascus CBHI/Cel7A activity was taken as an indication of the heterologous gene expression under the cbh1 promoter.
- Published
- 2007
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49. Thermostable enzymes in lignocellulose hydrolysis.
- Author
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Viikari L, Alapuranen M, Puranen T, Vehmaanperä J, and Siika-Aho M
- Subjects
- Biomass, Enzyme Stability, Hydrolysis, Temperature, Biotechnology trends, Cellulose chemistry, Energy-Generating Resources, Enzymes chemistry, Ethanol chemistry, Industry trends, Lignin chemistry
- Abstract
Thermostable enzymes offer potential benefits in the hydrolysis of lignocellulosic substrates; higher specific activity decreasing the amount of enzymes, enhanced stability allowing improved hydrolysis performance and increased flexibility with respect to process configurations, all leading to improvement of the overall economy of the process. New thermostable cellulase mixtures were composed of cloned fungal enzymes for hydrolysis experiments. Three thermostable cellulases, identified as the most promising enzymes in their categories (cellobiohydrolase, endoglucanase and beta-glucosidase), were cloned and produced in Trichoderma reesei and mixed to compose a novel mixture of thermostable cellulases. Thermostable xylanase was added to enzyme preparations used on substrates containing residual hemicellulose. The new optimised thermostable enzyme mixtures were evaluated in high temperature hydrolysis experiments on technical steam pretreated raw materials: spruce and corn stover. The hydrolysis temperature could be increased by about 10-15 degrees C, as compared with present commercial Trichoderma enzymes. The same degree of hydrolysis, about 90% of theoretical, measured as individual sugars, could be obtained with the thermostable enzymes at 60 degrees C as with the commercial enzymes at 45 degrees C. Clearly more efficient hydrolysis per assayed FPU unit or per amount of cellobiohydrolase I protein used was obtained. The maximum FPU activity of the novel enzyme mixture was about 25% higher at the optimum temperature at 65 degrees C, as compared with the highest activity of the commercial reference enzyme at 60 degrees C. The results provide a promising basis to produce and formulate improved enzyme products. These products can have high temperature stability in process conditions in the range of 55-60 degrees C (with present industrial products at 45-50 degrees C) and clearly improved specific activity, essentially decreasing the protein dosage required for an efficient hydrolysis of lignocellulosic substrates. New types of process configurations based on thermostable enzymes are discussed.
- Published
- 2007
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50. Structure of the ternary complex of human 17beta-hydroxysteroid dehydrogenase type 1 with 3-hydroxyestra-1,3,5,7-tetraen-17-one (equilin) and NADP+.
- Author
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Sawicki MW, Erman M, Puranen T, Vihko P, and Ghosh D
- Subjects
- Amino Acid Sequence, Animals, Binding Sites, Crystallography, X-Ray, Dimerization, Equilin chemistry, Humans, Least-Squares Analysis, Macromolecular Substances, Models, Molecular, Molecular Sequence Data, NADP chemistry, Recombinant Proteins chemistry, Recombinant Proteins metabolism, Spodoptera, Transfection, Equilin metabolism, Estradiol Dehydrogenases chemistry, Estradiol Dehydrogenases metabolism, NADP metabolism, Protein Conformation, Protein Structure, Secondary
- Abstract
Excess 17beta-estradiol (E2), the most potent of human estrogens, is known to act as a stimulus for the growth of breast tumors. Human estrogenic 17beta-hydroxysteroid dehydrogenase type 1 (17beta-HSD1), which catalyzes the reduction of inactive estrone (E1) to the active 17beta-estradiol in breast tissues, is a key enzyme responsible for elevated levels of E2 in breast tumor tissues. We present here the structure of the ternary complex of 17beta-HSD1 with the cofactor NADP+ and 3-hydroxyestra-1,3,5,7-tetraen-17-one (equilin), an equine estrogen used in estrogen replacement therapy. The ternary complex has been crystallized with a homodimer, the active form of the enzyme, in the asymmetric unit. Structural and kinetic data presented here show that the 17beta-HSD1-catalyzed reduction of E1 to E2 in vitro is specifically inhibited by equilin. The crystal structure determined at 3.0-A resolution reveals that the equilin molecule is bound at the active site in a mode similar to the binding of substrate. The orientation of the 17-keto group with respect to the nicotinamide ring of NADP+ and catalytic residues Tyr-155 and Ser-142 is different from that of E2 in the 17beta-HSD1-E2 complex. The ligand and substrate-entry loop densities are well defined in one subunit. The substrate-entry loop adopts a closed conformation in this subunit. The result demonstrates that binding of equilin at the active site of 17beta-HSD1 is the basis for inhibition of E1-to-E2 reduction by this equine estrogen in vitro. One possible outcome of estrogen replacement therapy in vivo could be reduction of E2 levels in breast tissues and hence the reduced risk of estrogen-dependent breast cancer.
- Published
- 1999
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