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Maes SL, Dietrich J, Midolo G, Schwieger S, Kummu M, Vandvik V, Aerts R, Althuizen IHJ, Biasi C, Björk RG, Böhner H, Carbognani M, Chiari G, Christiansen CT, Clemmensen KE, Cooper EJ, Cornelissen JHC, Elberling B, Faubert P, Fetcher N, Forte TGW, Gaudard J, Gavazov K, Guan Z, Guðmundsson J, Gya R, Hallin S, Hansen BB, Haugum SV, He JS, Hicks Pries C, Hovenden MJ, Jalava M, Jónsdóttir IS, Juhanson J, Jung JY, Kaarlejärvi E, Kwon MJ, Lamprecht RE, Le Moullec M, Lee H, Marushchak ME, Michelsen A, Munir TM, Myrsky EM, Nielsen CS, Nyberg M, Olofsson J, Óskarsson H, Parker TC, Pedersen EP, Petit Bon M, Petraglia A, Raundrup K, Ravn NMR, Rinnan R, Rodenhizer H, Ryde I, Schmidt NM, Schuur EAG, Sjögersten S, Stark S, Strack M, Tang J, Tolvanen A, Töpper JP, Väisänen MK, van Logtestijn RSP, Voigt C, Walz J, Weedon JT, Yang Y, Ylänne H, Björkman MP, Sarneel JM, Dorrepaal E. Environmental drivers of increased ecosystem respiration in a warming tundra. Nature 2024; 629:105-113. [PMID: 38632407 PMCID: PMC11062900 DOI: 10.1038/s41586-024-07274-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 03/06/2024] [Indexed: 04/19/2024]
Abstract
Arctic and alpine tundra ecosystems are large reservoirs of organic carbon1,2. Climate warming may stimulate ecosystem respiration and release carbon into the atmosphere3,4. The magnitude and persistency of this stimulation and the environmental mechanisms that drive its variation remain uncertain5-7. This hampers the accuracy of global land carbon-climate feedback projections7,8. Here we synthesize 136 datasets from 56 open-top chamber in situ warming experiments located at 28 arctic and alpine tundra sites which have been running for less than 1 year up to 25 years. We show that a mean rise of 1.4 °C [confidence interval (CI) 0.9-2.0 °C] in air and 0.4 °C [CI 0.2-0.7 °C] in soil temperature results in an increase in growing season ecosystem respiration by 30% [CI 22-38%] (n = 136). Our findings indicate that the stimulation of ecosystem respiration was due to increases in both plant-related and microbial respiration (n = 9) and continued for at least 25 years (n = 136). The magnitude of the warming effects on respiration was driven by variation in warming-induced changes in local soil conditions, that is, changes in total nitrogen concentration and pH and by context-dependent spatial variation in these conditions, in particular total nitrogen concentration and the carbon:nitrogen ratio. Tundra sites with stronger nitrogen limitations and sites in which warming had stimulated plant and microbial nutrient turnover seemed particularly sensitive in their respiration response to warming. The results highlight the importance of local soil conditions and warming-induced changes therein for future climatic impacts on respiration.
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Affiliation(s)
- S L Maes
- Climate Impacts Research Centre, Department of Ecology and Environmental Science, Umeå University, Abisko, Sweden.
- Forest Ecology and Management Group (FORECOMAN), Department of Earth and Environmental Sciences, KU Leuven, Leuven, Belgium.
| | - J Dietrich
- Climate Impacts Research Centre, Department of Ecology and Environmental Science, Umeå University, Abisko, Sweden
| | - G Midolo
- Department of Spatial Sciences, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Praha-Suchdol, Czech Republic
| | - S Schwieger
- Climate Impacts Research Centre, Department of Ecology and Environmental Science, Umeå University, Abisko, Sweden
- Department of Ecology and Environmental Science, Umeå University, Umeå, Sweden
| | - M Kummu
- Water and development research group, Aalto University, Espoo, Finland
| | - V Vandvik
- Department of Biological Sciences, University of Bergen, Bergen, Norway
- Bjerknes Centre for Climate Research, University of Bergen, Bergen, Norway
| | - R Aerts
- Amsterdam Institute for Life and Environment (A-LIFE), Vrije Universiteit, Amsterdam, The Netherlands
| | - I H J Althuizen
- Bjerknes Centre for Climate Research, University of Bergen, Bergen, Norway
- NORCE Climate and Environment, Norwegian Research Centre AS, Bergen, Norway
| | - C Biasi
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
- Department of Ecology, University of Innsbruck, Innsbruck, Austria
| | - R G Björk
- Department of Earth Sciences, University of Gothenburg, Gothenburg, Sweden
- Gothenburg Global Biodiversity Centre, Gothenburg, Sweden
| | - H Böhner
- Department of Arctic and Marine Biology, Faculty of Biosciences, Fisheries and Economics, The Arctic University of Norway, Tromsø, Norway
| | - M Carbognani
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, Italy
| | - G Chiari
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, Italy
| | - C T Christiansen
- Terrestrial Ecology Section, Department of Biology, University of Copenhagen, Copenhagen, Denmark
- Center for Permafrost, Department of Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
| | - K E Clemmensen
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - E J Cooper
- Department of Arctic and Marine Biology, UiT-the Arctic University of Norway, Tromsø, Norway
| | - J H C Cornelissen
- Amsterdam Institute for Life and Environment (A-LIFE), Vrije Universiteit, Amsterdam, The Netherlands
| | - B Elberling
- Center for Permafrost, Department of Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
| | - P Faubert
- Carbone Boréal, Département des Sciences Fondamentales, Université du Québec à Chicoutimi, Chicoutimi, Quebec, Canada
| | - N Fetcher
- Institute for Environmental Science and Sustainability, Wilkes University, Wilkes-Barre, PA, USA
| | - T G W Forte
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, Italy
| | - J Gaudard
- Department of Biological Sciences, University of Bergen, Bergen, Norway
- Bjerknes Centre for Climate Research, University of Bergen, Bergen, Norway
| | - K Gavazov
- Climate Impacts Research Centre, Department of Ecology and Environmental Science, Umeå University, Abisko, Sweden
- Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Lausanne, Switzerland
| | - Z Guan
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems and College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
| | - J Guðmundsson
- Agricultural University of Iceland, Reykjavik, Iceland
| | - R Gya
- Department of Biological Sciences, University of Bergen, Bergen, Norway
- Bjerknes Centre for Climate Research, University of Bergen, Bergen, Norway
| | - S Hallin
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - B B Hansen
- Department of Terrestrial Ecology, Norwegian Institute for Nature Research, Trondheim, Norway
- Gjærevoll Centre for Biodiversity Foresight Analyses & Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
| | - S V Haugum
- Department of Biological Sciences, University of Bergen, Bergen, Norway
- The Heathland Centre, Alver, Norway
| | - J-S He
- State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems and College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
- Institute of Ecology, College of Urban and Environmental Sciences, Key Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, Beijing, China
| | - C Hicks Pries
- Department of Biological Sciences, Dartmouth College, Hanover, NH, USA
| | - M J Hovenden
- Biological Sciences, School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
- Australian Mountain Research Facility, Canberra, Australian Capital Territory, Australia
| | - M Jalava
- Water and development research group, Aalto University, Espoo, Finland
| | - I S Jónsdóttir
- Life and Environmental Sciences, University of Iceland, Reykjavík, Iceland
| | - J Juhanson
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - J Y Jung
- Division of Life Sciences, Korea Polar Research Institute, Incheon, South Korea
| | - E Kaarlejärvi
- Research Centre for Ecological Change, Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - M J Kwon
- Korea Polar Research Institute, Incheon, Korea
- Institute of Soil Science, Universität Hamburg, Hamburg, Germany
| | - R E Lamprecht
- University of Eastern Finland, Department of Environmental and Biological Sciences, Kuopio, Finland
| | - M Le Moullec
- Gjærevoll Centre for Biodiversity Foresight Analyses & Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
- Greenland Institute of Natural Resources, Nuuk, Greenland
| | - H Lee
- NORCE, Norwegian Research Centre AS, Bjerknes Centre for Climate Research, Bergen, Norway
- Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
| | - M E Marushchak
- University of Eastern Finland, Department of Environmental and Biological Sciences, Kuopio, Finland
| | - A Michelsen
- Terrestrial Ecology Section, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - T M Munir
- Department of Geography, University of Calgary, Calgary, Alberta, Canada
| | - E M Myrsky
- Arctic Centre, University of Lapland, Rovaniemi, Finland
- Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - C S Nielsen
- Center for Permafrost, Department of Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
- SEGES Innovation P/S, Aarhus, Denmark
| | - M Nyberg
- Biological Sciences, School of Natural Sciences, University of Tasmania, Hobart, Tasmania, Australia
| | - J Olofsson
- Department of Ecology and Environmental Science, Umeå University, Umeå, Sweden
| | - H Óskarsson
- Agricultural University of Iceland, Reykjavik, Iceland
| | - T C Parker
- Ecological Sciences, The James Hutton Institute, Aberdeen, UK
| | - E P Pedersen
- Climate Impacts Research Centre, Department of Ecology and Environmental Science, Umeå University, Abisko, Sweden
- Terrestrial Ecology Section, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - M Petit Bon
- Department of Wildland Resources, Quinney College of Natural Resources and Ecology Center, Utah State University, Logan, UT, USA
- Department of Arctic Biology, University Centre in Svalbard, Longyearbyen, Norway
| | - A Petraglia
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, Parma, Italy
| | - K Raundrup
- Greenland Institute of Natural Resources, Nuuk, Greenland
| | - N M R Ravn
- Terrestrial Ecology Section, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - R Rinnan
- Center for Volatile Interactions, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - H Rodenhizer
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, USA
| | - I Ryde
- Terrestrial Ecology Section, Department of Biology, University of Copenhagen, Copenhagen, Denmark
- Center for Permafrost, Department of Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
| | - N M Schmidt
- Department of Ecoscience, Aarhus University, Roskilde, Denmark
- Arctic Research Centre, Aarhus University, Aarhus, Denmark
| | - E A G Schuur
- Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, USA
- Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, USA
| | - S Sjögersten
- School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough, UK
| | - S Stark
- Arctic Centre, University of Lapland, Rovaniemi, Finland
| | - M Strack
- Department of Geography and Environmental Management, University of Waterloo, Waterloo, Ontario, Canada
| | - J Tang
- The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA, USA
| | - A Tolvanen
- Natural Resources Institute Finland, Helsinki, Finland
| | - J P Töpper
- Norwegian Institute for Nature Research, Bergen, Norway
| | - M K Väisänen
- Arctic Centre, University of Lapland, Rovaniemi, Finland
- Ecology and Genetics Research Unit, University of Oulu, Oulu, Finland
| | - R S P van Logtestijn
- Amsterdam Institute for Life and Environment (A-LIFE), Vrije Universiteit, Amsterdam, The Netherlands
| | - C Voigt
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
- Institute of Soil Science, Universität Hamburg, Hamburg, Germany
| | - J Walz
- Climate Impacts Research Centre, Department of Ecology and Environmental Science, Umeå University, Abisko, Sweden
| | - J T Weedon
- Amsterdam Institute for Life and Environment (A-LIFE), Vrije Universiteit, Amsterdam, The Netherlands
| | - Y Yang
- State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - H Ylänne
- School of Forest Sciences, University of Eastern Finland, Joensuu, Finland
| | - M P Björkman
- Department of Earth Sciences, University of Gothenburg, Gothenburg, Sweden
- Gothenburg Global Biodiversity Centre, Gothenburg, Sweden
| | - J M Sarneel
- Department of Ecology and Environmental Science, Umeå University, Umeå, Sweden
| | - E Dorrepaal
- Climate Impacts Research Centre, Department of Ecology and Environmental Science, Umeå University, Abisko, Sweden
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Simoni M, Hanein T, Woo CL, Tyrer M, Nyberg M, Martinez JC, Quintero-Mora NI, Provis JL, Kinoshita H. Decarbonisation of calcium carbonate in sodium hydroxide solutions under ambient conditions: effect of residence time and mixing rates. Phys Chem Chem Phys 2022; 24:16125-16138. [PMID: 35748396 DOI: 10.1039/d2cp01412b] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The decarbonisation of CaCO3 is essential for the production of lime (Ca(OH)2 and CaO), which is a commodity required in several large industries and the main precursor for cement production. CaCO3 is usually decarbonised at high temperatures, generating gaseous CO2 which will require post-process capture to minimise its release into the environment. We have developed a new process that can decarbonise CaCO3 under ambient conditions, while sequestering the CO2 as Na2CO3·H2O or Na2CO3 in the same stage. Here, the effects of increasing stirring rates and residence times on reaction efficiency of the key reaction occurring between CaCO3 and NaOH solution are studied. It is shown that the reaction is enhanced at lower stirring rates and longer residence times up to 300 seconds of contact between the reactants. The mass balance performed for Ca and CO2 revealed that up to the 95% of the process CO2 embodied in CaCO3 was sequestered, with maximum capture rate assessed at nn moles CO2 captured per second of reaction progress. A deeper insight into the precipitation of Na2CO3·H2O or Na2CO3 under different reaction conditions was gained, and SEM-EDX analysis enabled the observation of the reaction front by detection of Na migrating towards inner regions of partially-reacted limestone chalk particles.
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Affiliation(s)
- Marco Simoni
- Department of Materials Science & Engineering, University of Sheffield, S1 3JD, Sheffield, UK.
| | - Theodore Hanein
- Department of Materials Science & Engineering, University of Sheffield, S1 3JD, Sheffield, UK.
| | - Chun Long Woo
- Department of Materials Science & Engineering, University of Sheffield, S1 3JD, Sheffield, UK.
| | - Mark Tyrer
- Collegium Basilea, Institute of Advanced Study, Hochstrasse 51, 4053 Basel, Switzerland
| | - Magnus Nyberg
- CEMEX Asia Research AG, Römerstrasse 13, 2555 Brügg, Switzerland
| | | | | | - John L Provis
- Department of Materials Science & Engineering, University of Sheffield, S1 3JD, Sheffield, UK.
| | - Hajime Kinoshita
- Department of Materials Science & Engineering, University of Sheffield, S1 3JD, Sheffield, UK.
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3
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Liedberg F, Abrahamsson J, Bobjer J, Gudjonsson S, Löfgren A, Nyberg M, Sörenby A. Robot-assisted nephroureterectomy for upper tract urothelial carcinoma-feasibility and complications: a single center experience. Scand J Urol 2022; 56:301-307. [PMID: 35736556 DOI: 10.1080/21681805.2022.2091018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
BACKGROUND Robot-assisted nephroureterectomy (RANU) is the primary treatment for upper tract urothelial carcinoma (UTUC) at our hospital for patients with clinical stage less than T2, and for patients with invasive tumours, but unfit for major surgery. OBJECTIVE To assess peri-operative conditions and outcomes of RANU at our unit, and to evaluate the safety of the procedure. METHODS The medical records of all 166 patients undergoing RANU for suspected UTUC and followed for more than three months in a large university hospital in Sweden were reviewed retrospectively. After the exclusion of twenty patients because of previous cystectomy, simultaneous surgical procedure, or other tumour types than UTUC in the pathological report, 146 patients remained for the analyses. The primary endpoint was complication rate according to Clavien-Dindo at 90 days. Secondary endpoints were perioperative bleeding, violation of oncological surgical principles, hospital stay, and re-admission within 90 days. RESULTS The median age was 75 [(Inter Quartile Range) IQR 70-80] years and 57% of the patients had an ASA score above 2. According to Clavien-Dindo, one patient had a grade 3 complication, and no patient had a grade 4-5 complication. The median blood loss was 50 (IQR 20-100) ml and the median hospital stay was 6 (IQR 5-7) days. Twelve patients were re-admitted to the hospital within 90 days (eight with urinary tract infection/haematuria, one with hematoma, and three with other diseases). CONCLUSION Robot-assisted nephroureterectomy is a safe procedure for patients with upper tract urothelial carcinoma, with a low risk of major surgical complications.
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Affiliation(s)
- F Liedberg
- Department of Urology, Skåne University Hospital, Malmö, Sweden.,Department of Translational Medicine, Lund University, Lund, Sweden
| | - J Abrahamsson
- Department of Urology, Skåne University Hospital, Malmö, Sweden.,Department of Translational Medicine, Lund University, Lund, Sweden
| | - J Bobjer
- Department of Urology, Skåne University Hospital, Malmö, Sweden.,Department of Translational Medicine, Lund University, Lund, Sweden
| | - S Gudjonsson
- Department of Urology, Landspitali University Hospital, Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | - A Löfgren
- Department of Urology, Skåne University Hospital, Malmö, Sweden.,Department of Translational Medicine, Lund University, Lund, Sweden
| | - M Nyberg
- Department of Urology, Skåne University Hospital, Malmö, Sweden.,Department of Translational Medicine, Lund University, Lund, Sweden
| | - A Sörenby
- Department of Urology, Skåne University Hospital, Malmö, Sweden.,Department of Translational Medicine, Lund University, Lund, Sweden
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4
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Simoni M, Hanein T, Woo CL, Nyberg M, Tyrer M, Provis JL, Kinoshita H. Synthesis of Ca(OH) 2 and Na 2CO 3 through anion exchange between CaCO 3 and NaOH: effect of reaction temperature. RSC Adv 2022; 12:32070-32081. [DOI: 10.1039/d2ra05827h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 10/13/2022] [Indexed: 11/13/2022] Open
Abstract
The chemical decarbonisation of CaCO3 was successfully tested in a range of mild temperatures simulating those oscillations occurring within processes, and the kinetic parameters were gained.
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Affiliation(s)
- Marco Simoni
- University of Sheffield, Department of Materials Science & Engineering, Sheffield, S1 3JD, UK
| | - Theodore Hanein
- University of Sheffield, Department of Materials Science & Engineering, Sheffield, S1 3JD, UK
| | - Chun Long Woo
- University of Sheffield, Department of Materials Science & Engineering, Sheffield, S1 3JD, UK
| | - Magnus Nyberg
- CEMEX Asia Research AG, Römerstrasse 13, Brügg 2555, Switzerland
| | - Mark Tyrer
- Collegium Basilea, Hochstrasse 51, Basel CH-4053, Switzerland
| | - John L. Provis
- University of Sheffield, Department of Materials Science & Engineering, Sheffield, S1 3JD, UK
| | - Hajime Kinoshita
- University of Sheffield, Department of Materials Science & Engineering, Sheffield, S1 3JD, UK
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5
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MacDonald SJ, Anderson S, Brereton P, Wood R, Barrett G, Brodie C, Burdaspal PA, Conley D, Cooper J, Darroch J, Donnelly C, Embrey N, Ennion RA, Felguerias I, Griffin J, Kitching M, Knight S, Lanham J, Legarda TM, Lenartowicz P, Luis E, Lundie JC, Möller T, Norwood D, Novo R, Nyberg M, O’Donnell C, Panzarini G, Pascale M, Patel S, Paulsch W, Payne N, Rawcliffe P, Reid K, Rizzo A, Rothin A, Saari L, Stangroom SG, Swanson W, Sweet P, Thomas T, Trani R, Turpin E, van Egmond HP, Walker M, Watkins JD, Williams C. Determination of Ochratoxin A in Currants, Raisins, Sultanas, Mixed Dried Fruit, and Dried Figs by Immunoaffinity Column Cleanup with Liquid Chromatography: Interlaboratory Study. J AOAC Int 2019. [DOI: 10.1093/jaoac/86.6.1164] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
An interlaboratory study was performed on behalf of the Food Standards Agency to evaluate the effectiveness of an affinity column cleanup liquid chromatographic (LC) method for the determination of ochratoxin A in a variety of dried fruit at European regulatory limits. To ensure homogeneity before analysis, laboratory samples are normally slurried with water in the ratio of 5 parts fruit to 4 parts water, and test materials in this form were used in the study. The test portion was extracted with acidified methanol. The extract was filtered, diluted with phosphate-buffered saline, and applied to an affinity column. The column was washed and ochratoxin A was eluted with methanol. Ochratoxin A was quantified by reversed-phase LC. The use of post-column pH shift to enhance the fluorescence of ochratoxin A by the addition of 1.1M ammonia solution to the column eluant is optional. Determination was by fluorescence. Currants, sultanas, raisins, figs, and mixed fruit (comprising dried pineapple, papaya, sultanas, prunes, dates, and banana chips), both naturally contaminated and blank (very low level), were sent to 24 collaborators in 7 European countries. Participants were asked to spike test portions of all test samples at a level equivalent to 5 ng/g ochra toxin A. Average recoveries ranged from 69 to 74%. Based on results for 5 naturally contaminated test samples (blind duplicates) the relative standard deviation for repeatability (RSDr) ranged from 4.9 to 8.7%, and the relative standard deviation for reproducibility (RSDR)rangedfrom14to28%. The method showed acceptable within-and be-tween-laboratory precision for all 5 matrixes, as evidenced by HORRAT values <1.3.
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Affiliation(s)
- Susan J MacDonald
- Central Science Laboratory, Sand Hutton, York, YO41 1LZ, United Kingdom
| | - Sharron Anderson
- Central Science Laboratory, Sand Hutton, York, YO41 1LZ, United Kingdom
| | - Paul Brereton
- Central Science Laboratory, Sand Hutton, York, YO41 1LZ, United Kingdom
| | - Roger Wood
- Food Standards Agency, Aviation House, 125 Kingsway, London, WC2B 6NH, United Kingdom
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6
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Stranne J, Axen E, Franck-Lissbrant I, Fransson P, Frånlund M, Hugosson J, Khatami A, Koss-Modig K, Lodding P, Nyberg M, Stattin P, Bratt O. Single institution followed by national implementation of systematic surgical quality control and feedback for radical prostatectomy: a 20-year journey. World J Urol 2019; 38:1397-1411. [PMID: 31388817 PMCID: PMC7245598 DOI: 10.1007/s00345-019-02887-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/23/2019] [Indexed: 11/24/2022] Open
Abstract
Purpose The demand for objective and outcome-based facts about surgical results after radical prostatectomy (RP) is increasing. Systematic feedback is also essential for each surgeon to improve his/her performance. Methods RP outcome data (e.g., pT-stage and margin status) have been registered at Sahlgrenska University Hospital (SUH) since 1988 and patient-related outcome measures (PROM) have been registered since 2001. The National Prostate Cancer Registry (NPCR) has covered all Regions in Sweden since 1998 and includes PROM-data from 2008. Initially PROM was on-paper questionnaires but due since 2018 all PROMs are collected electronically. In 2014 an on-line “dashboard” panel was introduced, showing the results for ten quality-control variables in real-time. Since 2017 all RP data on hospital, regional, and national levels are publicly accessible on-line on “www.npcr.se/RATTEN”. Results The early PROM-data from SUH have been used for internal quality control. As national clinical and PROM-data from the NPCR have been made accessible on-line and in real-time we have incorporated this into our pre-existing protocol. Our data are now internally available as real-time NPCR reports on the individual surgeons’ results, as well as ePROM data. We can compare the results of each surgeon internally and to other departments’ aggregated data. The public can access data and compare hospital level data on “RATTEN”. Conclusions The process of quality control of RP locally at SUH, and nationally through the NPCR, has been long but fruitful. The online design, with direct real-time feedback to the institutions that report the data, is essential.
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Affiliation(s)
- J Stranne
- Department of Urology, Institute of Clinical Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. .,Department of Urology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden.
| | - E Axen
- Department of Urology, Institute of Clinical Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Urology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden
| | - I Franck-Lissbrant
- Department of Oncology, Institute of Clinical Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Oncology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden
| | - P Fransson
- Department of Nursing, Umeå University, Umeå, Sweden
| | - M Frånlund
- Department of Urology, Institute of Clinical Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Urology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden
| | - J Hugosson
- Department of Urology, Institute of Clinical Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Urology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden
| | - A Khatami
- Department of Urology, Institute of Clinical Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Urology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden
| | - K Koss-Modig
- Department of Urology, Institute of Clinical Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Urology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden
| | - P Lodding
- Department of Urology, Institute of Clinical Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Urology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden
| | - M Nyberg
- Department of Urology, Institute of Clinical Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - P Stattin
- Department of Surgical Sciences, Uppsala University Hospital, Uppsala, Sweden
| | - O Bratt
- Department of Urology, Institute of Clinical Science, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Department of Urology, Sahlgrenska University Hospital, Region Västra Götaland, Gothenburg, Sweden
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Piil P, Jørgensen TS, Egelund J, Gliemann L, Hellsten Y, Nyberg M. Effect of high-intensity exercise training on functional sympatholysis in young and older habitually active men. Transl Sports Med 2018. [DOI: 10.1002/tsm2.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- P. Piil
- Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
| | - T. S. Jørgensen
- Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
- Department of Orthopedics; Herlev and Gentofte Hospital; Copenhagen Denmark
| | - J. Egelund
- Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
| | - L. Gliemann
- Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
| | - Y. Hellsten
- Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
| | - M. Nyberg
- Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
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Lundberg Slingsby MH, Nyberg M, Egelund J, Mandrup CM, Frikke-Schmidt R, Kirkby NS, Hellsten Y. Aerobic exercise training lowers platelet reactivity and improves platelet sensitivity to prostacyclin in pre- and postmenopausal women. J Thromb Haemost 2017; 15:2419-2431. [PMID: 29027349 DOI: 10.1111/jth.13866] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Indexed: 12/12/2022]
Abstract
Essentials It is unknown how regular exercise affects platelet function after menopause. We studied the effect of 3-months of high-intensity exercise in pre- and postmenopausal women. Platelet sensitivity to the inhibitory effect of arterially infused prostacyclin was increased. Reduced basal platelet reactivity was seen in the premenopausal women only. SUMMARY Background The risk of atherothrombotic events increases after the menopause. Regular physical activity has been shown to reduce platelet reactivity in younger women, but it is unknown how regular exercise affects platelet function after the menopause. Objectives To examine the effects of regular aerobic exercise in late premenopausal and recent postmenopausal women by testing basal platelet reactivity and platelet sensitivity to prostacyclin and nitric oxide. Methods Twenty-five sedentary, but healthy, late premenopausal and 24 matched recently postmenopausal women, mean (95% confidence interval) 49.1 (48.2-49.9) and 53.7 (52.5-55.0) years old, participated in an intervention study: 3-month high-intensity supervised aerobic spinning-cycle training (1 h, × 3/week). Basal platelet reactivity was analyzed in platelet-rich plasma from venous blood as agonist-induced % aggregation. In a subgroup of 13 premenopausal and 14 postmenopausal women, platelet reactivity was tested ex vivo after femoral arterial infusion of prostacyclin, acetylcholine, a cyclooxygenase inhibitor, and after acute one-leg knee extensor exercise. Results Basal platelet reactivity (%aggregation) to TRAP-6 (1 μm) was higher in the postmenopausal, 59% (50-68), than the premenopausal women, 45% (35-55). Exercise training reduced basal platelet reactivity to collagen (1 μg mL-1 ) in the premenopausal women only: from 63% (55-71%) to 51% (41-62%). After the training intervention, platelet aggregation was more inhibited by the arterial prostacyclin infusion and the acute exercise in both premenopausal and postmenopausal women. Conclusions These results highlight previously unknown cardioprotective aspects of regular aerobic exercise in premenopausal and postmenopausal women, improving their regulation of platelet reactivity through an increased platelet sensitivity to prostacyclin, which may counterbalance the increased atherothrombotic risk associated with the menopause.
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Affiliation(s)
- M H Lundberg Slingsby
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - M Nyberg
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - J Egelund
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - C M Mandrup
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - R Frikke-Schmidt
- Department of Clinical Biochemistry, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - N S Kirkby
- Department of Vascular Biology, National Heart and Lung Institute, Imperial College London, London, UK
| | - Y Hellsten
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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Nyberg M, Gliemann L, Hellsten Y. Vascular function in health, hypertension, and diabetes: effect of physical activity on skeletal muscle microcirculation. Scand J Med Sci Sports 2015; 25 Suppl 4:60-73. [DOI: 10.1111/sms.12591] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/28/2015] [Indexed: 12/31/2022]
Affiliation(s)
- M. Nyberg
- Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
| | - L. Gliemann
- Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
| | - Y. Hellsten
- Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
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Gliemann L, Buess R, Nyberg M, Hoppeler H, Odriozola A, Thaning P, Hellsten Y, Baum O, Mortensen SP. Capillary growth, ultrastructure remodelling and exercise training in skeletal muscle of essential hypertensive patients. Acta Physiol (Oxf) 2015; 214:210-20. [PMID: 25846822 DOI: 10.1111/apha.12501] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Revised: 03/23/2015] [Accepted: 03/30/2015] [Indexed: 01/04/2023]
Abstract
AIM The aim was to elucidate whether essential hypertension is associated with altered capillary morphology and density and to what extent exercise training can normalize these parameters. METHODS To investigate angiogenesis and capillary morphology in essential hypertension, muscle biopsies were obtained from m. vastus lateralis in subjects with essential hypertension (n = 10) and normotensive controls (n = 11) before and after 8 weeks of aerobic exercise training. Morphometry was performed after transmission electron microscopy, and protein levels of several angioregulatory factors were determined. RESULTS At baseline, capillary density and capillary-to-fibre ratio were not different between the two groups. However, the hypertensive subjects had 9% lower capillary area (12.7 ± 0.4 vs. 13.9 ± 0.2 μm(2)) and tended to have thicker capillary basement membranes (399 ± 16 vs. 358 ± 13 nm; P = 0.094) than controls. Protein expression of vascular endothelial growth factor (VEGF), VEGF receptor-2 and thrombospondin-1 were similar in normotensive and hypertensive subjects, but tissue inhibitor of matrix metalloproteinase was 69% lower in the hypertensive group. After training, angiogenesis was evident by 15% increased capillary-to-fibre ratio in the hypertensive subjects only. Capillary area and capillary lumen area were increased by 7 and 15% in the hypertensive patients, whereas capillary basement membrane thickness was decreased by 17% (P < 0.05). VEGF expression after training was increased in both groups, whereas VEGF receptor-2 was decreased by 25% in the hypertensive patients(P < 0.05). CONCLUSION Essential hypertension is associated with decreased lumen area and a tendency for increased basement membrane thickening in capillaries of skeletal muscle. Exercise training may improve the diffusion conditions in essential hypertension by altering capillary structure and capillary number.
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Affiliation(s)
- L. Gliemann
- Integrative Physiology Group; Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
| | - R. Buess
- Institute of Anatomy; University of Bern; Bern Switzerland
| | - M. Nyberg
- Integrative Physiology Group; Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
| | - H. Hoppeler
- Institute of Anatomy; University of Bern; Bern Switzerland
| | - A. Odriozola
- Institute of Anatomy; University of Bern; Bern Switzerland
| | - P. Thaning
- Copenhagen Muscle Research Centre; Rigshospitalet; Copenhagen Denmark
| | - Y. Hellsten
- Integrative Physiology Group; Department of Nutrition, Exercise and Sports; University of Copenhagen; Copenhagen Denmark
| | - O. Baum
- Institute of Anatomy; University of Bern; Bern Switzerland
| | - S. P. Mortensen
- Copenhagen Muscle Research Centre; Rigshospitalet; Copenhagen Denmark
- Department of Cardiovascular and Renal Research; University of Southern Denmark; Odense Denmark
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Nyberg M, Jalkanen V, Ramser K, Ljungberg B, Bergh A, Lindahl OA. Dual-modality probe intended for prostate cancer detection combining Raman spectroscopy and tactile resonance technology--discrimination of normal human prostate tissues ex vivo. J Med Eng Technol 2015; 39:198-207. [PMID: 25762203 DOI: 10.3109/03091902.2015.1021430] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Prostate cancer is the most common cancer for men in the western world. For the first time, a dual-modality probe, combining Raman spectroscopy and tactile resonance technology, has been used for assessment of fresh human prostate tissue. The study investigates the potential of the dual-modality probe by testing its ability to differentiate prostate tissue types ex vivo. Measurements on four prostates show that the tactile resonance modality was able to discriminate soft epithelial tissue and stiff stroma (p < 0.05). The Raman spectra exhibited a strong fluorescent background at the current experimental settings. However, stroma could be discerned from epithelia by integrating the value of the spectral background. Combining both parameters by a stepwise analysis resulted in 100% sensitivity and 91% specificity. Although no cancer tissue was analysed, the results are promising for further development of the instrument and method for discriminating prostate tissues and cancer.
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Affiliation(s)
- M Nyberg
- Department of Engineering Sciences and Mathematics, Luleå University of Technology , Luleå , Sweden
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12
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Gliemann L, Nyberg M, Hellsten Y. Nitric oxide and reactive oxygen species in limb vascular function: what is the effect of physical activity? Free Radic Res 2013; 48:71-83. [PMID: 23962038 DOI: 10.3109/10715762.2013.835045] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Nitric oxide (NO) is known to be one of the most important regulatory compounds within the cardiovascular system where it is central for functions such as regulation of blood pressure, blood flow, and vascular growth. The bioavailability of NO is determined by a balance between, on one hand, the extent of enzymatic and non-enzymatic formation of NO and on the other hand, removal of NO, which in part is dependent on the reaction of NO with reactive oxygen species (ROS). The presence of ROS is dependent on the extent of ROS formation via mitochondria and/or enzymes such as NAD(P)H oxidase (NOX) and xanthine oxidase (XO) and the degree of ROS removal through the antioxidant defense system or other reactions. The development of cardiovascular disease has been proposed to be closely related to a reduced bioavailability of NO in parallel with an increased presence of ROS. Excessive levels of ROS not only lower the bioavailability of NO but may also cause cellular damage in the cardiovascular system. Physical activity has been shown to greatly improve cardiovascular function, in part through improved bioavailability of NO, enhanced endogenous antioxidant defense and a lowering of the expression of ROS-forming enzymes. Regular physical activity is therefore likely to be a highly useful tool in the treatment of cardiovascular disease. Future studies should focus on which form of exercise may be most optimal for enhancing NO bioavailability and improving cardiovascular health.
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Affiliation(s)
- L Gliemann
- Department of Nutrition, Exercise and Sports, Section for Integrative Physiology, Cardiovascular Physiology, University of Copenhagen , Copenhagen , Denmark
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13
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Nyberg M, Mortensen SP, Hellsten Y. Physical activity opposes the age-related increase in skeletal muscle and plasma endothelin-1 levels and normalizes plasma endothelin-1 levels in individuals with essential hypertension. Acta Physiol (Oxf) 2013; 207:524-35. [PMID: 23227981 DOI: 10.1111/apha.12048] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 11/22/2012] [Accepted: 12/05/2012] [Indexed: 01/02/2023]
Abstract
AIMS Endothelin-1 has potent constrictor and proliferative activity in vascular smooth muscle, and essential hypertension and aging are associated with increased endothelin-1-mediated vasoconstrictor tone. The aim of this study was to investigate the effect of physical activity, hypertension and age on endothelin-1 levels in plasma and skeletal muscle and endothelin receptors in skeletal muscle in human subjects. METHODS In study 1, normotensive (46 ± 1 years, n = 11) and hypertensive (47 ± 1 years, n = 10) subjects were studied before and after 8 weeks of aerobic exercise training. In study 2, young (23 ± 1 years, n = 8), older lifelong sedentary (66 ± 2 years, n = 8) and older lifelong endurance-trained (62 ± 2 years, n = 8) subjects were studied in a cross-sectional design. RESULTS Skeletal muscle and plasma endothelin-1 levels were increased with age and plasma endothelin-1 levels were higher in hypertensive than normotensive individuals. Eight weeks of exercise training normalized plasma endothelin-1 levels in the hypertensive subjects and increased the protein expression of the ET(A) receptor in skeletal muscle of normotensive subjects. Similarly, individuals that had performed lifelong physical activity had similar plasma and muscle endothelin-1 levels as the young controls and had higher ET(A) receptor levels. CONCLUSION Our findings suggest that aerobic exercise training opposes the age-related increase in skeletal muscle and plasma endothelin-1 levels and normalizes plasma endothelin-1 levels in individuals with essential hypertension. This effect may explain some of the beneficial effects of training on the cardiovascular system in older and hypertensive subjects.
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Affiliation(s)
| | - S. P. Mortensen
- Copenhagen Muscle Research Centre; University of Copenhagen; Copenhagen; Denmark
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Ekblom O, Kraepelien-Strid E, Tidén A, Nyberg M, Sundblad GB, Lundvall S. Predictors of perceived competence in physical activities (PCPA) among Swedish adolescents, a longitudinal study. J Sci Med Sport 2012. [DOI: 10.1016/j.jsams.2012.11.276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Ekblom O, Kraepelien-Strid E, Tidén A, Nyberg M, Sundblad GB, Lundvall S. Predictors of adolescent fitness levels among Swedish adolescents, a longitudinal study. J Sci Med Sport 2012. [DOI: 10.1016/j.jsams.2012.11.449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Christensen PM, Nyberg M, Bangsbo J. Influence of nitrate supplementation on VO₂ kinetics and endurance of elite cyclists. Scand J Med Sci Sports 2012; 23:e21-31. [PMID: 23020760 DOI: 10.1111/sms.12005] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/22/2012] [Indexed: 01/01/2023]
Abstract
The present study examined if an elevated nitrate intake would improve VO(2) kinetics, endurance, and repeated sprint capacity in elite endurance athletes. Ten highly trained cyclists (72 ± 4 mL O(2) /kg/min, mean ± standard deviation) underwent testing for VO(2) kinetics (3 × 6 min at 298 ± 28 W), endurance (120 min preload followed by a 400-kcal time trial), and repeated sprint capacity (6 × 20 s sprints, recovery 100 s) during two 6-day periods in randomized order with a daily ingestion of either 0.5 L beetroot (BR) juice to increase nitrate levels or a 0.5 L placebo (PLA) drink with blackcurrant juice. Plasma NOx (nitrate + nitrite) levels were higher (P < 0.01) in BR (147 ± 102 and 159 ± 103 μM after 4 and 6 days of beverage intake, respectively) compared with PLA (41 ± 10 and 40 ± 7 μM). VO(2) kinetics and exercise economy were the same in BR and PLA. Time-trial performance was similar with an average completion time of 18:20 and 18:37 min:s in BR and PLA, respectively, with average power outputs of 290 ± 43 W in BR and 285 ± 44 W in PLA. Peak and mean power during repeated sprinting were similar in BR and PLA. In contrast to observations in moderately trained subjects intake of BR juice had no effect on VO(2) kinetics and performance in elite cyclists.
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Affiliation(s)
- P M Christensen
- Copenhagen Muscle Research Centre, Department of Exercise and Sport Sciences, Section of Human Physiology, University of Copenhagen, Copenhagen, Denmark
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Abstract
During exercise, oxygen delivery to skeletal muscle is elevated to meet the increased oxygen demand. The increase in blood flow to skeletal muscle is achieved by vasodilators formed locally in the muscle tissue, either on the intraluminal or on the extraluminal side of the blood vessels. A number of vasodilators have been shown to bring about this increase in blood flow and, importantly, interactions between these compounds seem to be essential for the precise regulation of blood flow. Two compounds stand out as central in these vasodilator interactions: nitric oxide (NO) and prostacyclin. These two vasodilators are both stimulated by several compounds, e.g. adenosine, ATP, acetylcholine and bradykinin, and are affected by mechanically induced signals, such as shear stress. NO and prostacyclin have also been shown to interact in a redundant manner where one system can take over when formation of the other is compromised. Although numerous studies have examined the role of single and multiple pharmacological inhibition of different vasodilator systems, and important vasodilators and interactions have been identified, a large part of the exercise hyperaemic response remains unexplained. It is plausible that this remaining hyperaemia may be explained by cAMP- and cGMP-independent smooth muscle relaxation, such as effects of endothelial derived hyperpolarization factors (EDHFs) or through metabolic modulation of sympathetic effects. The nature and role of EDHF as well as potential novel mechanisms in muscle blood flow regulation remain to be further explored to fully elucidate the regulation of exercise hyperaemia.
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Affiliation(s)
- Y Hellsten
- Department of Exercise and Sport Sciences, Division of Integrated Cardiovascular Physiology, University of Copenhagen, Copenhagen, Denmark.
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18
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Mortensen SP, Nyberg M, Winding K, Saltin B. Lifelong physical activity preserves functional sympatholysis and purinergic signalling in the ageing human leg. J Physiol 2012; 590:6227-36. [PMID: 22966164 DOI: 10.1113/jphysiol.2012.240093] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Ageing is associated with an impaired ability to modulate sympathetic vasoconstrictor activity (functional sympatholysis) and a reduced exercise hyperaemia. The purpose of this study was to investigate whether a physically active lifestyle can offset the impaired functional sympatholysis and exercise hyperaemia in the leg and whether ATP signalling is altered by ageing and physical activity. Leg haemodynamics, interstitial [ATP] and P2Y(2) receptor content was determined in eight young (23 ± 1 years), eight lifelong sedentary elderly (66 ± 2 years) and eight lifelong active elderly (62 ± 2 years) men at rest and during one-legged knee extensions (12 W and 45% maximal workload (WL(max))) and arterial infusion of ACh and ATP with and without tyramine. The vasodilatory response to ACh was lowest in the sedentary elderly, higher in active elderly (P < 0.05) and highest in the young men (P < 0.05), whereas ATP-induced vasodilatation was lower in the sedentary elderly (P < 0.05). During exercise (12 W), leg blood flow, vascular conductance and VO2 was lower and leg lactate release higher in the sedentary elderly compared to the young (P < 0.05), whereas there was no difference between the active elderly and young. Interstitial [ATP] during exercise and P2Y(2) receptor content were higher in the active elderly compared to the sedentary elderly (P < 0.05). Tyramine infusion lowered resting vascular conductance in all groups, but only in the sedentary elderly during exercise (P < 0.05). Tyramine did not alter the vasodilator response to ATP infusion in any of the three groups. Plasma [noradrenaline] increased more during tyramine infusion in both elderly groups compared to young (P < 0.05). A lifelong physically active lifestyle can maintain an intact functional sympatholysis during exercise and vasodilator response to ATP despite a reduction in endothelial nitric oxide function. A physically active lifestyle increases interstitial ATP levels and skeletal muscle P2Y(2) receptor content.
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Affiliation(s)
- S P Mortensen
- The Copenhagen Muscle Research Centre, Rigshospitalet, Section 7641, Blegdamsvej 9, DK-2100 Copenhagen Ø, Denmark.
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Candefjord S, Murayama Y, Nyberg M, Hallberg J, Ramser K, Ljungberg B, Bergh A, Lindahl OA. Combining scanning haptic microscopy and fibre optic Raman spectroscopy for tissue characterization. J Med Eng Technol 2012; 36:319-27. [DOI: 10.3109/03091902.2012.687035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Hellsten Y, Nyberg M, Mortensen SP. Contribution of intravascular versus interstitial purines and nitric oxide in the regulation of exercise hyperaemia in humans. J Physiol 2012; 590:5015-23. [PMID: 22733661 DOI: 10.1113/jphysiol.2012.234963] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The regulation of blood flow to skeletal muscle involves a complex interaction between several locally formed vasodilators that are produced both in the skeletal muscle interstitium and intravascularly. The gas nitric oxide (NO) and the purines ATP and adenosine, are potent vasodilators that are formed by multiple cell types and released into the skeletal muscle interstitium and in plasma in response to muscle contraction. Cellular sources of ATP and NO in plasma are erythrocytes and endothelial cells, whereas interstitial sources are skeletal muscle cells and endothelial cells. Adenosine originates primarily from extracellular degradation of ATP. During exercise the concentrations of ATP and adenosine increase markedly in the interstitium with smaller increases occurring in plasma, and thus the interstitial concentration during exercise is severalfold higher than in plasma. The concentration of NO metabolites (NOx) in interstitium and plasma does not change during exercise and is similar in the two compartments. Adenosine and NO have been shown to contribute to exercise hyperaemia whereas the role of ATP remains unclear due to lack of specific purinergic receptor blockers. The relative role of intravascular versus interstitial vasodilators is not known but evidence suggests that both compartments are important. In cardiovascular disease, a reduced capacity to form adenosine in the muscle interstitium may be a contributing factor in increased peripheral vascular resistance.
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Affiliation(s)
- Y Hellsten
- Department of Exercise and Sport Sciences, University of Copenhagen, Universitetsparken 1, DK-2100 Copenhagen Ø, Denmark.
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Fredlund E, Thim AM, Gidlund A, Brostedt S, Nyberg M, Olsen M. Moulds and mycotoxins in rice from the Swedish retail market. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2009; 26:527-33. [DOI: 10.1080/02652030802562912] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Krysander M, Aslund J, Nyberg M. An Efficient Algorithm for Finding Minimal Overconstrained Subsystems for Model-Based Diagnosis. ACTA ACUST UNITED AC 2008. [DOI: 10.1109/tsmca.2007.909555] [Citation(s) in RCA: 143] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Alfredsson Y, Brena B, Nilson K, Ahlund J, Kjeldgaard L, Nyberg M, Luo Y, Mårtensson N, Sandell A, Puglia C, Siegbahn H. Electronic structure of a vapor-deposited metal-free phthalocyanine thin film. J Chem Phys 2007; 122:214723. [PMID: 15974778 DOI: 10.1063/1.1924539] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The electronic structure of a vapor-sublimated thin film of metal-free phthalocyanine (H2Pc) is studied experimentally and theoretically. An atom-specific picture of the occupied and unoccupied electronic states is obtained using x-ray-absorption spectroscopy (XAS), core- and valence-level x-ray photoelectron spectroscopy (XPS), and density-functional theory (DFT) calculations. The DFT calculations allow for an identification of the contributions from individual nitrogen atoms to the experimental N1s XAS and valence XPS spectra. This comprehensive study of metal-free phthalocyanine is relevant for the application of such molecules in molecular electronics and provides a solid foundation for identifying modifications in the electronic structure induced by various substituent groups.
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Affiliation(s)
- Y Alfredsson
- Department of Physics, Uppsala University, Box 530, S-751 21, Uppsala, Sweden
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Nyberg M, Föhlisch A, Triguero L, Bassan A, Nilsson A, Pettersson L. Bonding in metal–carbonyls: A comparison with experiment and calculations on adsorbed CO. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.theochem.2005.10.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Nilsson A, Ogasawara H, Cavalleri M, Nordlund D, Nyberg M, Wernet P, Pettersson LGM. The hydrogen bond in ice probed by soft x-ray spectroscopy and density functional theory. J Chem Phys 2005; 122:154505. [PMID: 15945643 DOI: 10.1063/1.1879752] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
We combine photoelectron and x-ray absorption spectroscopy with density functional theory to derive a molecular orbital picture of the hydrogen bond in ice. We find that the hydrogen bond involves donation and back-donation of charge between the oxygen lone pair and the O-H antibonding orbitals on neighboring molecules. Together with internal s-p rehybridization this minimizes the repulsive charge overlap of the connecting oxygen and hydrogen atoms, which is essential for a strong attractive electrostatic interaction. Our joint experimental and theoretical results demonstrate that an electrostatic model based on only charge induction from the surrounding medium fails to properly describe the internal charge redistributions upon hydrogen bonding.
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Affiliation(s)
- A Nilsson
- Stanford Synchrotron Radiation Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
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Möller TE, Nyberg M. Efficiency of different extraction solvent mixtures used in analyses of aflatoxins from a certified peanut meal reference material. ACTA ACUST UNITED AC 2004; 21:781-5. [PMID: 15370829 DOI: 10.1080/02652030412331282394] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Four analytical methods with different extraction solvent mixtures were used to compare the efficiency of the extraction step in the analysis of aflatoxins from a reference material with a certified value of 206 +/- 13 microg aflatoxin B(1) kg(-1). The extraction mixtures used were chloroform-water (100 + 10), acetonitrile-water (60 + 40), acetone-water (85 + 15) and methanol-water (80 + 20). The analytical values determined from the extraction mixtures after correction for recovery were 211, 204, 163 and 120 microg kg(-1), respectively. The small amounts of aflatoxin B(2) in the reference material followed the same pattern. The selection of extraction solvent mixture is very important for achieving the true value and that correction for recovery does not always fully compensate for getting the correct analytical value.
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Affiliation(s)
- T E Möller
- National Food Administration, Uppsala, Sweden
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Lauritsen J, Nyberg M, Nørskov J, Clausen B, Topsøe H, Lægsgaard E, Besenbacher F. Hydrodesulfurization reaction pathways on MoS2 nanoclusters revealed by scanning tunneling microscopy. J Catal 2004. [DOI: 10.1016/j.jcat.2004.02.009] [Citation(s) in RCA: 270] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Nyberg M, Odelius M, Nilsson A, Pettersson LGM. Hydrogen bonding between adsorbed deprotonated glycine molecules on Cu(110). J Chem Phys 2003. [DOI: 10.1063/1.1625640] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Möller TE, Nyberg M. Ochratoxin A in raisins and currants: basic extraction procedure used in two small marketing surveys of the occurrence and control of the heterogeneity of the toxins in samples. ACTA ACUST UNITED AC 2003; 20:1072-6. [PMID: 14668157 DOI: 10.1080/02652030310001615212] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
A basic extraction procedure for analysis of ochratoxin A (OTA) in currants and raisins is described, as well as the occurrence of OTA and a control of heterogeneity of the toxin in samples bought for two small marketing surveys 1999/2000 and 2001/02. Most samples in the surveys were divided into two subsamples that were individually prepared as slurries and analysed separately. The limit of quantification for the method was estimated as 0.1 microg kg(-1) and recoveries of 85, 90 and 115% were achieved in recovery experiments at 10, 5 and 0.1 microg kg(-1), respectively. Of all 118 subsamples analysed in the surveys, 96 (84%) contained ochratoxin A at levels above the quantification level and five samples (4%) contained more than the European Community legislation of 10 microg kg(-1). The OTA concentrations found in the first survey were in the range < 0.1-19.0 microg kg(-1) with a median concentration of 0.9 microg kg(-1). In the 2001/02 study, the range was < 0.1-34.6 microg kg(-1) with a median of 0.2 microg kg(-1). Big differences were often achieved between individual subsamples of the original sample, which indicate a wide heterogeneous distribution of the toxin. Data from the repeatability test as well as recovery experiments from the same slurries showed that preparation of slurries as described here seemed to give a homogeneous and representative sample. The extraction with the basic sodium bicarbonate-methanol mixture used in the surveys gave similar or somewhat higher OTA values on some samples tested in a comparison with a weak phosphoric acid water-methanol extraction mixture.
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Affiliation(s)
- T E Möller
- National Food Administration, Box 622 SE-751 26 Uppsala, Sweden.
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Sillanpää J, Huikko S, Nyberg M, Kivi P, Laippala P, Uitti J. Effect of work with visual display units on musculo-skeletal disorders in the office environment. Occup Med (Lond) 2003; 53:443-51. [PMID: 14581641 DOI: 10.1093/occmed/kqg120] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The increase in computer and mouse use has been associated with an increased prevalence of disorders in the neck and upper extremities. Furthermore, poor workstation design has been associated with an increased risk of developing these symptoms. Aim The aims of this study were (i) to estimate the prevalence of musculo-skeletal disorders among full-time visual display unit (VDU) users; (ii) to examine how the prevalence varies by work environment; and (iii) to explore the association with work factors. METHOD A survey was carried out on the effect of work with VDUs on musculo-skeletal disorders in workers in the office environment of 56 workplaces. Office workers (n = 298), customer service workers (n = 238) and designers (n = 247) were studied. RESULTS For all the occupations combined, the 12 month prevalences of musculo-skeletal symptoms in the neck, shoulders, elbows, lower arms and wrists, and fingers were 63, 24, 18, 35 and 16%, respectively. The study indicated that musculo-skeletal pain is common among computer workers in offices. There was no strong association between the duration of computer work and pain or between the duration of mouse use and pain, but workers' perception of their workstation as being poor ergonomically was strongly associated with an increased prevalence of pain. CONCLUSIONS Musculo-skeletal symptoms are common, but the duration of daily keyboard and mouse use had no connection with musculo-skeletal symptoms. Instead, more consideration should be paid to the ergonomics of workstations, the placing of the mouse, the postures of the upper extremities and the handling of the mouse.
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Affiliation(s)
- J Sillanpää
- Tampere Regional Institute of Occupational Health, Tampere, Finland.
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Oström H, Triguero L, Nyberg M, Ogasawara H, Pettersson LGM, Nilsson A. Bonding of saturated hydrocarbons to metal surfaces. Phys Rev Lett 2003; 91:046102. [PMID: 12906678 DOI: 10.1103/physrevlett.91.046102] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2003] [Indexed: 05/24/2023]
Abstract
The adsorption of octane on Cu(110) was studied by x-ray absorption and x-ray emission spectroscopy, in combination with spectrum calculations in the framework of density functional theory, as a model system for alkane adsorption on transition metals. Significant electron sharing between the adsorbate and metal surface and involvement of both bonding and antibonding C-H molecular orbitals in the molecule-metal bond was found. The calculations were extended to the case of octane adsorbed on Ni(110), and the position of the metal d band was found to be important for the bonding. The results were generalized to show that this is important for the efficiency as an alkane dehydrogenation catalyst.
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Affiliation(s)
- H Oström
- FYSIKUM, Stockholm University, Albanova University Center, SE-106 91 Stockholm, Sweden
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Öström H, Triguero L, Weiss K, Ogasawara H, Garnier MG, Nordlund D, Nyberg M, Pettersson LGM, Nilsson A. Orbital rehybridization in n-octane adsorbed on Cu(110). J Chem Phys 2003. [DOI: 10.1063/1.1539866] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Ogasawara H, Brena B, Nordlund D, Nyberg M, Pelmenschikov A, Pettersson LGM, Nilsson A. Structure and bonding of water on Pt(111). Phys Rev Lett 2002; 89:276102. [PMID: 12513221 DOI: 10.1103/physrevlett.89.276102] [Citation(s) in RCA: 235] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2002] [Indexed: 05/24/2023]
Abstract
We address the adsorption of water on Pt(111) using x-ray absorption, x-ray emission, and x-ray photoelectron spectroscopy along with calculations in the framework of density functional theory. Using the direct relationship between the electronic structure and adsorbate geometry, we show that in the first layer all the molecules bind directly to the surface and to each other through the in-layer H bonds without dissociation, creating a nearly flat overlayer. The water molecules are adsorbed through alternating metal-oxygen (M-O) and metal-hydrogen (M-HO) bonds.
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Affiliation(s)
- H Ogasawara
- FYSIKUM, Stockholm University, Albanova University Center, S-10691 Stockholm, Sweden
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Goldoni A, Cepek C, Larciprete R, Sangaletti L, Pagliara S, Floreano L, Gotter R, Verdini A, Morgante A, Luo Y, Nyberg M. C70 adsorbed on Cu(111): Metallic character and molecular orientation. J Chem Phys 2002. [DOI: 10.1063/1.1467346] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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36
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Lodding P, Bergdahl C, Nyberg M, Pileblad E, Stranne J, Hugosson J. Inguinal hernia after radical retropubic prostatectomy for prostate cancer: a study of incidence and risk factors in comparison to no operation and lymphadenectomy. J Urol 2001; 166:964-7. [PMID: 11490256 DOI: 10.1016/s0022-5347(05)65874-0] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE The incidence, mechanisms and risk factors of inguinal hernia after radical retropubic prostatectomy are sparsely elucidated in the literature. We determined the rate of inguinal hernia after radical retropubic prostatectomy and compared it to the incidence in patients with prostate cancer who did not undergo operation or underwent only pelvic lymph node dissection. MATERIALS AND METHODS We followed 375, 184 and 65 men who underwent radical retropubic prostatectomy plus pelvic lymph node dissection, pelvic lymph node dissection only and no surgery with respect to inguinal hernia for a mean of 39, 47 and 45 months, respectively. The prostatectomy group was also evaluated in regard to the potential risk factors of previous hernia surgery and post-prostatectomy anastomotic stricture. RESULTS The incidence of hernia was 13.6%, 7.6% and 3.1% in the prostatectomy, lymph node dissection and unoperated group, respectively. The difference was statistically significant in the prostatectomy and unoperated groups according to the Mantel-Cox log rank test and Cox proportional hazards rate. Previous hernial surgery and post-prostatectomy anastomotic stricture were more common in patients with an inguinal hernia after prostatectomy. CONCLUSIONS The incidence of inguinal hernia is clearly increased in men who have undergone radical retropubic prostatectomy plus pelvic lymph node dissection compared with those who undergo no surgery for prostate cancer. Inguinal hernia appears to develop more often in men with prostate cancer who undergo radical retropubic prostatectomy and pelvic lymph node dissection than in those who undergo pelvic lymph node dissection only. While surgical factors trigger hernial development, previous hernial surgery and post-prostatectomy anastomotic stricture may be important risk factors. In fact, the latter may largely explain the difference in the incidence of inguinal hernia in our lymph node dissection and prostatectomy groups. Prophylactic surgical procedures must be evaluated to address this problem.
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Affiliation(s)
- P Lodding
- Department of Urology, Sahlgrenska University Hospital, Göteborg, Sweden
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Pettersson LG, Nilsson A, Myneni S, Luo Y, Nyberg M, Cavalleri M, Ojamäe L, Näslund LA, Ogasawara H, Odelius M, Pelmenschikov A. Electronic structure effects from hydrogen bonding in the liquid phase and in chemisorption: an integrated theory and experimental effort. J Synchrotron Radiat 2001; 8:136-140. [PMID: 11512711 DOI: 10.1107/s0909049500020355] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2000] [Accepted: 12/15/2000] [Indexed: 05/23/2023]
Abstract
A closely integrated theoretical and experimental effort to understand chemical bonding using X-ray spectroscopic probes is presented. Theoretical techniques to simulate XAS (X-ray absorption spectroscopy), XES (X-ray emission spectroscopy), RIXS (resonant inelastic X-ray scattering) and XPS (X-ray photoelectron spectroscopy) spectra have been developed and implemented within a density functional theory (DFT) framework. In combination with new experimental techniques, such as high-resolution XAS on liquid water under ambient conditions and XES on complicated surface adsorbates, new insight into e.g. hydrogen-bonded systems is obtained. For the (3x2) overlayer structure of glycine/Cu(110), earlier work has been extended to include adsorbate-adsorbate interactions. Structures are optimized for large cluster models and for periodic boundary conditions. It is found that specific features in the spectra arise from hydrogen-bonding interactions, which thus have important effects at the molecular-orbital level. XAS on liquid water shows a pronounced pre-edge feature with significant intensity, while the spectrum of ice shows only little intensity in this region. Theoretical spectrum calculations, based on instantaneous structures obtained from molecular-dynamics (MD) simulations, show that the pre-edge feature in the liquid is caused by water molecules with unsaturated hydrogen bonding. Some aspects of the theoretical simulations will be briefly discussed.
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Hasselström J, Karis O, Nyberg M, Pettersson LGM, Weinelt M, Wassdahl N, Nilsson A. The Bonding and Electronic Structure Changes upon Adsorption of Important Functional Groups: Glycine on Copper. J Phys Chem B 2000. [DOI: 10.1021/jp000986z] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J. Hasselström
- Department of Physics, Uppsala University, Box 530, S-751 21 Uppsala, Sweden, and FYSIKUM, University of Stockholm, Box 6730, S-113 85 Stockholm, Sweden
| | - O. Karis
- Department of Physics, Uppsala University, Box 530, S-751 21 Uppsala, Sweden, and FYSIKUM, University of Stockholm, Box 6730, S-113 85 Stockholm, Sweden
| | - M. Nyberg
- Department of Physics, Uppsala University, Box 530, S-751 21 Uppsala, Sweden, and FYSIKUM, University of Stockholm, Box 6730, S-113 85 Stockholm, Sweden
| | - L. G. M. Pettersson
- Department of Physics, Uppsala University, Box 530, S-751 21 Uppsala, Sweden, and FYSIKUM, University of Stockholm, Box 6730, S-113 85 Stockholm, Sweden
| | - M. Weinelt
- Department of Physics, Uppsala University, Box 530, S-751 21 Uppsala, Sweden, and FYSIKUM, University of Stockholm, Box 6730, S-113 85 Stockholm, Sweden
| | - N. Wassdahl
- Department of Physics, Uppsala University, Box 530, S-751 21 Uppsala, Sweden, and FYSIKUM, University of Stockholm, Box 6730, S-113 85 Stockholm, Sweden
| | - A. Nilsson
- Department of Physics, Uppsala University, Box 530, S-751 21 Uppsala, Sweden, and FYSIKUM, University of Stockholm, Box 6730, S-113 85 Stockholm, Sweden
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Föhlisch A, Nyberg M, Hasselström J, Karis O, Pettersson LG, Nilsson A. How carbon monoxide adsorbs in different sites. Phys Rev Lett 2000; 85:3309-3312. [PMID: 11019328 DOI: 10.1103/physrevlett.85.3309] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/1999] [Indexed: 05/23/2023]
Abstract
The interplay between the electronic and the geometric structure of adsorbates is of fundamental importance for the understanding of many surface phenomena. Using x-ray emission spectroscopy and ab initio cluster calculations, this issue has been investigated in unprecedented detail for CO adsorption in different adsorption sites. The investigation establishes pi bonding and sigma repulsion, both increasing with the number of coordinated metal atoms. The two contributions partly compensate each other, leading to only small differences in adsorption energies for the different adsorption sites despite very large variations in the electronic structure.
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Affiliation(s)
- A Föhlisch
- Department of Physics, Uppsala University, Box 530, S-751 21 Uppsala, Sweden
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40
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Karis O, Hasselström J, Wassdahl N, Weinelt M, Nilsson A, Nyberg M, Pettersson LGM, Stöhr J, Samant MG. The bonding of simple carboxylic acids on Cu(110). J Chem Phys 2000. [DOI: 10.1063/1.481415] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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41
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Nyberg M, Hasselström J, Karis O, Wassdahl N, Weinelt M, Nilsson A, Pettersson LGM. The electronic structure and surface chemistry of glycine adsorbed on Cu(110). J Chem Phys 2000. [DOI: 10.1063/1.481110] [Citation(s) in RCA: 153] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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42
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Föhlisch A, Nyberg M, Bennich P, Triguero L, Hasselström J, Karis O, Pettersson LGM, Nilsson A. The bonding of CO to metal surfaces. J Chem Phys 2000. [DOI: 10.1063/1.480773] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Hasselström J, Föhlisch A, Karis O, Wassdahl N, Weinelt M, Nilsson A, Nyberg M, Pettersson LGM, Stöhr J. Ammonia adsorbed on Cu(110): An angle resolved x-ray spectroscopic and ab initio study. J Chem Phys 1999. [DOI: 10.1063/1.478374] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Elman MJ, Sugar J, Fiscella R, Deutsch TA, Noth J, Nyberg M, Packo K, Anderson RJ. The effect of propranolol versus placebo on resident surgical performance. Trans Am Ophthalmol Soc 1998; 96:283-91; discussion 291-4. [PMID: 10360293 PMCID: PMC1298399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
PURPOSE To determine whether propranolol can decrease surgical tremor and anxiety in residents performing ocular microsurgery without impairing patient or physician safety. METHODS In this randomized, double-masked, crossover study, 5 third-year ophthalmology residents ingested a capsule containing either propranolol, 40 mg, or placebo 1 hour prior to performing ophthalmic microsurgery. All residents were healthy men under age 30 years. Prior to commencement of the study, all participants had successfully been administered a test dose of propranolol without side effects. The study took place over a 10-week period. At the conclusion of each case, both the resident and attending surgeon observer independently completed a form grading, on a sliding scale: (1) amount of overall tremor; (2) amount of tremor during placement of the first 3 sutures after lens or nucleus extraction; (3) anticipated difficulty of the case; (4) actual difficulty with the case; and (5) anxiety (surgeon only). In addition, the type of procedure performed, complications encountered, and surgeon side effects were recorded. The data were analyzed with a 2-way analysis of variance for unbalanced data. RESULTS A total of 73 surgical cases were performed; the surgeons were administered propranolol for 40 cases and placebo for 33. As judged by the resident surgeon, there was a highly significant effect of propranolol in decreasing anxiety (P = .0058), reducing surgical tremor overall (P < .0001), and reducing tremor while placing the first 3 sutures following lens extraction (P < .0001). There was no treatment-by-surgeon interaction for any of the measures. Complications and difficulty of the case, as judged by both the resident and attending surgeons, were not significantly different in the propranolol versus placebo groups (P > .05). There were no side effects reported or observed in any of the surgeons. CONCLUSIONS Propranolol, 40 mg, administered 1 hour prior to surgery, significantly decreases tremor and anxiety in the surgeon without untoward effects to the surgeon and the patient. However, it is unknown whether decreased tremor and anxiety improved surgical outcome.
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Affiliation(s)
- M J Elman
- Department of Ophthalmology, University of Illinois Eye and Ear Infirmary, USA
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Ranki A, Nyberg M, Ovod V, Haltia M, Elovaara I, Raininko R, Haapasalo H, Krohn K. Abundant expression of HIV Nef and Rev proteins in brain astrocytes in vivo is associated with dementia. AIDS 1995; 9:1001-8. [PMID: 8527071 DOI: 10.1097/00002030-199509000-00004] [Citation(s) in RCA: 231] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE To relate the expression of HIV regulatory proteins and HIV-specific mRNA in the brain cells of infected individuals with clinical neurological disease. DESIGN Formalin-fixed postmortem brain tissue from 14 HIV-infected adult patients, with previous repeated neurological and neuroradiological examinations, was studied by immunohistochemical and molecular biological methods. Samples from non-infected brains served as controls. METHODS Immunohistochemistry with monoclonal antibodies (MAb) was combined with in situ RNA hybridization. Target cells were identified with MAb to glial fibrillary acidic protein (GFAP; astrocytes), CD68 (activated macrophages) and Ricinus communis agglutinin (RCA-1; microglia, endothelial cells). For HIV, a panel of MAb against HIV Nef, Tat, Rev and Env proteins or probes specific for all classes of mRNA (nef), for singly or non-spliced mRNA (env) and for non-spliced mRNA (gag/pol) were used. RESULTS Nef protein was detected in subcortical or subpial astrocytes in seven out of 14 samples, and in multinucleated giant cells in two cases. Gag/pol or env mRNA-expressing astrocytes were detected in four cases. In four out of five cases studied, HIV Rev, but not Tat, was also expressed in astrocytes. Six out of the seven patients with Nef-positive astrocytes had suffered from moderate to severe dementia. The patient with most rapidly progressing severe dementia showed extensive HIV mRNA expression together with Nef and Rev expression in astrocytes. CONCLUSION In adult human brain, astrocytes are infected by HIV and preferentially express HIV Nef and Rev proteins but are also sometimes productively infected. Astrocyte infection is associated with moderate to severe dementia which agrees with recent knowledge on the housekeeping activities of astrocytes and their eventual role in learning and memory.
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Affiliation(s)
- A Ranki
- Department of Dermatology and Venereal Diseases, University of Helsinki, Finland
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46
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Karhunen PJ, Brummer-Korvenkontio H, Leinikki P, Nyberg M. Stability of human immunodeficiency virus (HIV) antibodies in postmortem samples. J Forensic Sci 1994; 39:129-35. [PMID: 8113695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The stability of human immunodeficiency virus (HIV) antibodies was studied for samples of sera, vitreous fluid and bile obtained from eight HIV-positive autopsy cases. The autopsy delay was on average 5 days. The samples were stored at room temperature (20 degrees C) for 51 to 314 days and tested repeatedly. In Western blotting on fresh postmortem samples, the antibodies detected most of the proteins of the virus. Antibodies against all major envelope, core and transmembrane proteins, although weakened, were also detected in stored sera. In stored vitreous fluid and bile the envelope protein gp 160, the transmembrane protein gp 41 and in half of the cases also the major core protein p 24 could still be detected. The disappearance of p 24 was associated with AIDS, but was detected in all samples from patients with early infection. Of screening tests, the enzyme-linked immunosorbent assay applying synthetic peptide as an antigen detected antibodies from all serum samples, but was less applicable to vitreous fluid or bile. Another immunoassay, applying recombinant antigen, succeeded in vitreous fluid and bile but not in sera. The rapid visually read assay detected antibodies in most samples of fresh whole blood, bile and in most of the vitreous samples, but was less useful on stored specimens.
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Affiliation(s)
- P J Karhunen
- Department of Public Health, University of Tampere, Finland
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47
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Ingelman G, Jönsson L, Nyberg M. Deep-inelastic scattering on intrinsic charm quarks in the proton. Phys Rev D Part Fields 1993; 47:4872-4882. [PMID: 10015495 DOI: 10.1103/physrevd.47.4872] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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48
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Nyberg M, Kulonen K, Neuvonen E, Ek-Kommonen C, Nuorgam M, Westerling B. An epidemic of sylvatic rabies in Finland--descriptive epidemiology and results of oral vaccination. Acta Vet Scand 1992; 33:43-57. [PMID: 1598857 PMCID: PMC8117877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/1990] [Accepted: 06/10/1991] [Indexed: 12/27/2022] Open
Abstract
When rabies reappeared in Finland in April 1988, the country had been rabies free since 1959. Soon a picture of sylvatic rabies become evident, its main vector and victim being the raccoon dog (Nyctereutes procyonoides). Between 8 April 1988 and 16 February 1989, 66 virologically verified cases were recorded (48 raccoon dogs, 12 red foxes, 2 badgers, 2 cats, 1 dog and 1 dairy bull) in an area estimated at 1700 km2 in south-eastern Finland. The greatest distance between recorded cases was 67 km. A positive reaction with monoclonal antibody p-41 indicated that the virus was an arctic-type strain. A field trial on oral immunization of small predators was initiated in September 1988 using Tübingen fox baits according to the Bavarian model of bait distribution. Each bait contained 5*10(7) TCID50/ml modified live rabies virus (SAD-B19). The 6 months' surveillance indicate a seroconversion rate of 72% (N = 126) in the raccoon dog population, 67% (N = 56) in the red foxes and 13% (N = 16) in the badgers, when titers greater than or equal to 1.0 IU/ml are considered seropositive. In the whole follow-up period, no statistically significant difference could be detected between the raccoon dogs and red foxes in the rate of seroconversion or in the uptake of tetracycline from the baits. Notably high antibody levels were recorded in both raccoon dogs and red foxes within 4-5 months after vaccination. Of the seropositive animals, the proportion of animals with titers 3.0 IU/ml or greater was higher in raccoon dogs (73%) than in red foxes (51%) (x2 = 5.29, p less than 0.05). The trial shows that raccoon dogs can be immunized against rabies in the field with vaccine baits originally developed for controlling sylvatic rabies in foxes.
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Affiliation(s)
- M Nyberg
- Field Department, National Veterinary Institute, Helsinki, Finland
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49
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Nyberg M. Turnaround time. A financially troubled Philadelphia hospital goes out of the red and into the black. Health Prog 1991; 72:57-61. [PMID: 10109970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
Abstract
A large Medicare population, a higher than average length of stay, an aging medical staff, and difficulty in retaining professional staff were a few of the indications that Nazareth Hospital, Philadelphia, was headed for financial difficulties. Unfortunately, Nazareth leaders overlooked these warnings because the hospital was concentrating on a major construction project. In 1989 the hospital lost approximately $5 million from operations, resulting in debt covenant violations on a $33 million bond issue. Nazareth then adopted a revitalization program with the following basic components: Establishing extensive cost-cutting measures to help reverse the financial deficits Retaining outside consultants to serve as management advocates and to keep the repositioning effort moving forward Enhancing long-range strategic planning to lay firm groundwork for the hospital's future As a result of these efforts, Nazareth went from a fiscal year 1989 operating loss to a 1990 year-end break-even position. Nazareth leaders attribute this success to the total commitment by the involved constituencies: board, managers, medical staff, and employees.
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Abstract
Blood and tissue were studied for potential infectivity at autopsy of ten patients with human immunodeficiency virus (HIV) infection. Special attention was paid to the possibility of detecting HIV in bone at craniotomy. Postmortem intervals were one to six days. Specimens for HIV isolation included skull bone, brain, blood, bone marrow, spleen, and lymph node, and cerebrospinal fluid in one case. HIV grew in culture from at least one specimen from eight autopsies, one of which was performed six days postmortem. HIV was recovered from the blood of five patients and the tissue of five patients, including three with negative blood cultures. Skull bone contained HIV in two cases. HIV also grew from native spleen specimens stored for up to 14 days postmortem at 20 degrees C. Recommended precautions, including those for bone, are indicated at autopsy of HIV-infected patients even after long postmortem intervals.
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Affiliation(s)
- M Nyberg
- Department of Pathology, Aurora Hospital, Helsinki, Finland
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