1
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Ohayon B, Janka G, Cortinovis I, Burkley Z, Borges LDS, Depero E, Golovizin A, Ni X, Salman Z, Suter A, Vigo C, Prokscha T, Crivelli P. Precision Measurement of the Lamb Shift in Muonium. Phys Rev Lett 2022; 128:011802. [PMID: 35061492 DOI: 10.1103/physrevlett.128.011802] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 12/15/2021] [Indexed: 06/14/2023]
Abstract
We report a new measurement of the n=2 Lamb shift in Muonium. Our result of 1047.2(2.3)_{stat}(1.1)_{syst} MHz comprises an order of magnitude improvement upon the previous best measurement. This value matches the theoretical calculation within 1 standard deviation allowing us to set limits on Lorentz and CPT violation in the muonic sector, as well as on new physics coupled to muons and electrons which could provide an explanation of the muon g-2 anomaly.
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Affiliation(s)
- B Ohayon
- Institute for Particle Physics and Astrophysics, ETH Zürich, CH-8093 Zürich, Switzerland
| | - G Janka
- Institute for Particle Physics and Astrophysics, ETH Zürich, CH-8093 Zürich, Switzerland
| | - I Cortinovis
- Institute for Particle Physics and Astrophysics, ETH Zürich, CH-8093 Zürich, Switzerland
| | - Z Burkley
- Institute for Particle Physics and Astrophysics, ETH Zürich, CH-8093 Zürich, Switzerland
| | - L de Sousa Borges
- Institute for Particle Physics and Astrophysics, ETH Zürich, CH-8093 Zürich, Switzerland
| | - E Depero
- Institute for Particle Physics and Astrophysics, ETH Zürich, CH-8093 Zürich, Switzerland
| | - A Golovizin
- P.N. Lebedev Physical Institute, 53 Leninsky prospekt., Moscow 119991, Russia
| | - X Ni
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Z Salman
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - A Suter
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - C Vigo
- Institute for Particle Physics and Astrophysics, ETH Zürich, CH-8093 Zürich, Switzerland
| | - T Prokscha
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - P Crivelli
- Institute for Particle Physics and Astrophysics, ETH Zürich, CH-8093 Zürich, Switzerland
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2
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Fittipaldi R, Hartmann R, Mercaldo MT, Komori S, Bjørlig A, Kyung W, Yasui Y, Miyoshi T, Olde Olthof LAB, Palomares Garcia CM, Granata V, Keren I, Higemoto W, Suter A, Prokscha T, Romano A, Noce C, Kim C, Maeno Y, Scheer E, Kalisky B, Robinson JWA, Cuoco M, Salman Z, Vecchione A, Di Bernardo A. Unveiling unconventional magnetism at the surface of Sr 2RuO 4. Nat Commun 2021; 12:5792. [PMID: 34608149 PMCID: PMC8490454 DOI: 10.1038/s41467-021-26020-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 09/14/2021] [Indexed: 11/09/2022] Open
Abstract
Materials with strongly correlated electrons often exhibit interesting physical properties. An example of these materials is the layered oxide perovskite Sr2RuO4, which has been intensively investigated due to its unusual properties. Whilst the debate on the symmetry of the superconducting state in Sr2RuO4 is still ongoing, a deeper understanding of the Sr2RuO4 normal state appears crucial as this is the background in which electron pairing occurs. Here, by using low-energy muon spin spectroscopy we discover the existence of surface magnetism in Sr2RuO4 in its normal state. We detect static weak dipolar fields yet manifesting at an onset temperature higher than 50 K. We ascribe this unconventional magnetism to orbital loop currents forming at the reconstructed Sr2RuO4 surface. Our observations set a reference for the discovery of the same magnetic phase in other materials and unveil an electronic ordering mechanism that can influence electron pairing with broken time reversal symmetry.
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Affiliation(s)
- R Fittipaldi
- CNR-SPIN, c/o University of Salerno, I-84084, Fisciano, Salerno, Italy.,Dipartimento di Fisica "E.R. Caianiello", University of Salerno, I-84084, Fisciano, Salerno, Italy
| | - R Hartmann
- Department of Physics, University of Konstanz, 78457, Konstanz, Germany
| | - M T Mercaldo
- Dipartimento di Fisica "E.R. Caianiello", University of Salerno, I-84084, Fisciano, Salerno, Italy
| | - S Komori
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, CB3 0FS, UK.,Department of Physics, Nagoya University, Nagoya, 464-8602, Japan
| | - A Bjørlig
- Department of Physics, Bar Ilan University, Ramat Gan, 5920002, Israel
| | - W Kyung
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Korea
| | - Y Yasui
- Department of Physics, Kyoto University, Kyoto, 606-8502, Japan.,RIKEN, Centre for Emergent Matter Science, Saitama, 351-0198, Japan
| | - T Miyoshi
- Department of Physics, Kyoto University, Kyoto, 606-8502, Japan
| | - L A B Olde Olthof
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, CB3 0FS, UK
| | - C M Palomares Garcia
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, CB3 0FS, UK
| | - V Granata
- Dipartimento di Fisica "E.R. Caianiello", University of Salerno, I-84084, Fisciano, Salerno, Italy
| | - I Keren
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen, PSI, Switzerland.,The Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem, 91904, Israel
| | - W Higemoto
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki, 319-1195, Japan
| | - A Suter
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen, PSI, Switzerland
| | - T Prokscha
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen, PSI, Switzerland
| | - A Romano
- CNR-SPIN, c/o University of Salerno, I-84084, Fisciano, Salerno, Italy.,Dipartimento di Fisica "E.R. Caianiello", University of Salerno, I-84084, Fisciano, Salerno, Italy
| | - C Noce
- CNR-SPIN, c/o University of Salerno, I-84084, Fisciano, Salerno, Italy.,Dipartimento di Fisica "E.R. Caianiello", University of Salerno, I-84084, Fisciano, Salerno, Italy
| | - C Kim
- Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Korea
| | - Y Maeno
- Department of Physics, Kyoto University, Kyoto, 606-8502, Japan
| | - E Scheer
- Department of Physics, University of Konstanz, 78457, Konstanz, Germany
| | - B Kalisky
- Department of Physics, Bar Ilan University, Ramat Gan, 5920002, Israel
| | - J W A Robinson
- Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, CB3 0FS, UK
| | - M Cuoco
- CNR-SPIN, c/o University of Salerno, I-84084, Fisciano, Salerno, Italy. .,Dipartimento di Fisica "E.R. Caianiello", University of Salerno, I-84084, Fisciano, Salerno, Italy.
| | - Z Salman
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232, Villigen, PSI, Switzerland.
| | - A Vecchione
- CNR-SPIN, c/o University of Salerno, I-84084, Fisciano, Salerno, Italy.,Dipartimento di Fisica "E.R. Caianiello", University of Salerno, I-84084, Fisciano, Salerno, Italy
| | - A Di Bernardo
- Department of Physics, University of Konstanz, 78457, Konstanz, Germany.
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Smith NM, Maloney NG, Shaw S, Horgan GW, Fyfe C, Martin JC, Suter A, Scott KP, Johnstone AM. Daily Fermented Whey Consumption Alters the Fecal Short-Chain Fatty Acid Profile in Healthy Adults. Front Nutr 2020; 7:165. [PMID: 33102510 PMCID: PMC7556162 DOI: 10.3389/fnut.2020.00165] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [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: 05/19/2020] [Accepted: 08/10/2020] [Indexed: 12/14/2022] Open
Abstract
Gut microbiota influences many aspects of host health including immune, metabolic, and gut health. We examined the effect of a fermented whey concentrate (FWC) drink rich in L-(+)-Lactic acid, consumed daily, in 18 healthy men (n = 5) and women (n = 13) in free-living conditions. Objective: The aims of this 6-weeks pilot trial were to (i) identify changes in the gut microbiota composition and fecal short chain fatty acid (SCFA) profile, and (ii) to monitor changes in glucose homeostasis. Results: Total fecal SCFA (mM) concentration remained constant throughout the intervention. Proportionally, there was a significant change in the composition of different SCFAs compared to baseline. Acetate levels were significantly reduced (−6.5%; p < 0.01), coupled to a significant increase in the relative amounts of propionate (+2.2%; p < 0.01) and butyrate (+4.2%; p < 0.01), respectively. No changes in the relative abundance of any specific bacteria were detected. No significant changes were observed in glucose homeostasis in response to an oral glucose tolerance test. Conclusion: Daily consumption of a fermented whey product led to significant changes in fecal SCFA metabolite profile, indicating some potential prebiotic activity. These changes did not result in any detectable differences in microbiota composition. Post-hoc analysis indicated that baseline microbiota composition might be indicative of participants likely to see changes in SCFA levels. However, due to the lack of a control group these findings would need to be verified in a rigorously controlled trial. Future work is also required to identify the biological mechanisms underlying the observed changes in microbiota activity and to explore if these processes can be harnessed to favorably impact host health. Clinical Trial Registration: www.clinicaltrials.gov, identifier NCT03615339; retrospectively registered on 03/08/2018.
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Affiliation(s)
- Nicola M Smith
- School of Medicine, Medical Sciences and Nutrition, The Rowett Institute, University of Aberdeen, Aberdeen, United Kingdom
| | - Niamh G Maloney
- School of Medicine, Medical Sciences and Nutrition, The Rowett Institute, University of Aberdeen, Aberdeen, United Kingdom
| | - Sophie Shaw
- Centre for Genome Enabled Biology and Medicine, University of Aberdeen, Aberdeen, United Kingdom
| | - Graham W Horgan
- Biomathematics & Statistics Scotland, University of Aberdeen, Aberdeen, United Kingdom
| | - Claire Fyfe
- School of Medicine, Medical Sciences and Nutrition, The Rowett Institute, University of Aberdeen, Aberdeen, United Kingdom
| | - Jennifer C Martin
- School of Medicine, Medical Sciences and Nutrition, The Rowett Institute, University of Aberdeen, Aberdeen, United Kingdom
| | | | - Karen P Scott
- School of Medicine, Medical Sciences and Nutrition, The Rowett Institute, University of Aberdeen, Aberdeen, United Kingdom
| | - Alexandra M Johnstone
- School of Medicine, Medical Sciences and Nutrition, The Rowett Institute, University of Aberdeen, Aberdeen, United Kingdom
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4
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Janka G, Ohayon B, Burkley Z, Gerchow L, Kuroda N, Ni X, Nishi R, Salman Z, Suter A, Tuzi M, Vigo C, Prokscha T, Crivelli P. Intense beam of metastable Muonium. Eur Phys J C Part Fields 2020; 80:804. [PMID: 32922165 PMCID: PMC7462919 DOI: 10.1140/epjc/s10052-020-8400-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 08/24/2020] [Indexed: 06/11/2023]
Abstract
Precision spectroscopy of the Muonium Lamb shift and fine structure requires a robust source of 2S Muonium. To date, the beam-foil technique is the only demonstrated method for creating such a beam in vacuum. Previous experiments using this technique were statistics limited, and new measurements would benefit tremendously from the efficient 2S production at a low energy muon ( < 20 keV) facility. Such a source of abundant low energyμ + has only become available in recent years, e.g. at the Low-Energy Muon beamline at the Paul Scherrer Institute. Using this source, we report on the successful creation of an intense, directed beam of metastable Muonium. We find that even though the theoretical Muonium fraction is maximal in the low energy range of 2-5 keV, scattering by the foil and transport characteristics of the beamline favor slightly higherμ + energies of 7-10 keV. We estimate that an event detection rate of a few events per second for a future Lamb shift measurement is feasible, enabling an increase in precision by two orders of magnitude over previous determinations.
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Affiliation(s)
- G. Janka
- Institute for Particle Physics and Astrophysics, ETH Zürich, 8093 Zurich, Switzerland
| | - B. Ohayon
- Institute for Particle Physics and Astrophysics, ETH Zürich, 8093 Zurich, Switzerland
| | - Z. Burkley
- Institute for Particle Physics and Astrophysics, ETH Zürich, 8093 Zurich, Switzerland
| | - L. Gerchow
- Institute for Particle Physics and Astrophysics, ETH Zürich, 8093 Zurich, Switzerland
| | - N. Kuroda
- Institute of Physics, The University of Tokyo, Tokyo, 153-8902 Japan
| | - X. Ni
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland
| | - R. Nishi
- Institute of Physics, The University of Tokyo, Tokyo, 153-8902 Japan
| | - Z. Salman
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland
| | - A. Suter
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland
| | - M. Tuzi
- Institute for Particle Physics and Astrophysics, ETH Zürich, 8093 Zurich, Switzerland
| | - C. Vigo
- Institute for Particle Physics and Astrophysics, ETH Zürich, 8093 Zurich, Switzerland
| | - T. Prokscha
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland
| | - P. Crivelli
- Institute for Particle Physics and Astrophysics, ETH Zürich, 8093 Zurich, Switzerland
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5
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Simões AFA, Alberto HV, Vilão RC, Gil JM, Cunha JMV, Curado MA, Salomé PMP, Prokscha T, Suter A, Salman Z. Muon implantation experiments in films: Obtaining depth-resolved information. Rev Sci Instrum 2020; 91:023906. [PMID: 32113453 DOI: 10.1063/1.5126529] [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] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 01/30/2020] [Indexed: 06/10/2023]
Abstract
Implanted positive muons with low energies (in the range 1-30 keV) are extremely useful local probes in the study of thin films and multi-layer structures. The average muon stopping depth, typically in the order of tens of nanometers, is a function of the muon implantation energy and of the density of the material, but the stopping range extends over a broad region, which is also in the order of tens of nanometers. Therefore, an adequate simulation procedure is required in order to extract the depth dependence of the experimental parameters. Here, we present a method to extract depth-resolved information from the implantation energy dependence of the experimental parameters in a low-energy muon spin spectroscopy experiment. The method and corresponding results are exemplified for a semiconductor film, Cu(In,Ga)Se2, covered with a thin layer of Al2O3, but can be applied to any heterostructure studied with low-energy muons. It is shown that if an effect is present in the experimental data, this method is an important tool to identify its location and depth extent.
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Affiliation(s)
- A F A Simões
- CFisUC, Department of Physics, University of Coimbra, R. Larga, P-3004-516 Coimbra, Portugal
| | - H V Alberto
- CFisUC, Department of Physics, University of Coimbra, R. Larga, P-3004-516 Coimbra, Portugal
| | - R C Vilão
- CFisUC, Department of Physics, University of Coimbra, R. Larga, P-3004-516 Coimbra, Portugal
| | - J M Gil
- CFisUC, Department of Physics, University of Coimbra, R. Larga, P-3004-516 Coimbra, Portugal
| | - J M V Cunha
- International Iberian Nanotechnology Laboratory, 4715-330 Braga, Portugal
| | - M A Curado
- CFisUC, Department of Physics, University of Coimbra, R. Larga, P-3004-516 Coimbra, Portugal
| | - P M P Salomé
- International Iberian Nanotechnology Laboratory, 4715-330 Braga, Portugal
| | - T Prokscha
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - A Suter
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Z Salman
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
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6
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Flokstra MG, Stewart R, Satchell N, Burnell G, Luetkens H, Prokscha T, Suter A, Morenzoni E, Langridge S, Lee SL. Observation of Anomalous Meissner Screening in Cu/Nb and Cu/Nb/Co Thin Films. Phys Rev Lett 2018; 120:247001. [PMID: 29957008 DOI: 10.1103/physrevlett.120.247001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2018] [Indexed: 06/08/2023]
Abstract
We have observed the spatial distribution of magnetic flux in Nb, Cu/Nb, and Cu/Nb/Co thin films using muon-spin rotation. In an isolated 50-nm-thick Nb film, we find a weak flux expulsion (Meissner effect) which becomes significantly enhanced when adding an adjacent 40 nm layer of Cu. The added Cu layer exhibits a Meissner effect (due to induced superconducting pairs) and is at least as effective as the Nb to expel flux. These results are confirmed by theoretical calculations using the quasiclassical Green's function formalism. An unexpected further significant enhancement of the flux expulsion is observed when adding a thin (2.4 nm) ferromagnetic Co layer to the bottom side of the Nb. This observed cooperation between superconductivity and ferromagnetism, by an unknown mechanism, forms a key ingredient for developing superconducting spintronics.
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Affiliation(s)
- M G Flokstra
- School of Physics and Astronomy, SUPA, University of St. Andrews, St. Andrews KY16 9SS, United Kingdom
| | - R Stewart
- School of Physics and Astronomy, SUPA, University of St. Andrews, St. Andrews KY16 9SS, United Kingdom
| | - N Satchell
- ISIS, Rutherford Appleton Laboratory, Oxfordshire OX11 0QX, United Kingdom
| | - G Burnell
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - H Luetkens
- Labor für Myonspinspektroskopie, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - T Prokscha
- Labor für Myonspinspektroskopie, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - A Suter
- Labor für Myonspinspektroskopie, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - E Morenzoni
- Labor für Myonspinspektroskopie, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - S Langridge
- ISIS, Rutherford Appleton Laboratory, Oxfordshire OX11 0QX, United Kingdom
| | - S L Lee
- School of Physics and Astronomy, SUPA, University of St. Andrews, St. Andrews KY16 9SS, United Kingdom
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7
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Suter A, Engelhart-Jentzsch K. In vitro bioavailability of fatty acids and fatty acid esters of two saw palmetto preparations. Am J Transl Res 2017. [DOI: 10.1055/s-0037-1608392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- A Suter
- A. Vogel Bioforce AG, Roggwil, Switzerland
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8
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Vimalanathan S, Schoop R, Suter A. Echinacea purpurea extract can reverse respiratory virus induced secondary bacterial infection. Am J Transl Res 2017. [DOI: 10.1055/s-0037-1608444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
| | - R Schoop
- A. Vogel Bioforce AG, Roggwil TG, Switzerland
| | - A Suter
- A. Vogel Bioforce AG, Roggwil TG, Switzerland
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9
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Vimalanathan S, Schoop R, Suter A, Hudson J. Prevention of influenza virus induced bacterial superinfection by standardized Echinacea purpurea, via regulation of surface receptor expression in human bronchial epithelial cells. Virus Res 2017; 233:51-59. [PMID: 28279802 DOI: 10.1016/j.virusres.2017.03.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [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: 11/27/2016] [Revised: 02/21/2017] [Accepted: 03/01/2017] [Indexed: 01/30/2023]
Abstract
Viral infections may predispose the airways to secondary bacterial infections that can lead to unfavorable progression of principally self-limiting illnesses. Such complicated respiratory infections include pneumonia, bronchitis, sinusitis, acute otitis media, and sepsis, which cause high morbidity and lethality. Some of the pathogenic consequences of viral infections, like the expression of bacterial adhesion receptors and the disturbance of physical barrier integrity due to inflammation, may create permissive conditions for co-infections. Influenza virus A (H3N2) is a major pathogen that causes secondary bacterial infections and inflammation that lead to pneumonia. The herbal medicine Echinacea purpurea, on the other hand, has been widely used to prevent and treat viral respiratory infections, and recent clinical data suggest that it may prevent secondary infection complications as well. We investigated the role of standardized E. purpurea (Echinaforce® extract or EF) on H3N2-induced adhesion of live nontypeable Haemophilus influenzae (NTHi) and Staphylococcus aureus, along with the expression of bacterial receptors, intracellular adhesion molecule-1 (ICAM-1), fibronectin, and platelet activating factor receptor (PAFr), by BEAS-2B cells. Inflammatory processes were investigated by determining the cellular expression of IL-6 and IL-8 and the involvement of Toll-like receptor (TLR-4) and NFκB p65. We found that influenza virus A infection increased the adhesion of H. influenzae and S. aureus to bronchial epithelial cells via upregulated expression of the ICAM-1 receptor and, to some extent, of fibronectin and PAFr. Echinaforce (EF) significantly reduced the expression of ICAM-1, fibronectin, and PAFr and consequently the adhesion of both bacterial strains. EF also effectively prevented the super-expression of inflammatory cytokines by suppressing the expression of NFκB and possibly TLR-4. These results indicate that E. purpurea has the potential to reduce the risk of respiratory complications by preventing virus-induced bacterial adhesion and through the inhibition of inflammation super-stimulation (cytokine storms).
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Affiliation(s)
- Selvarani Vimalanathan
- Department of Pathology & Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada V6T 2B5.
| | - Roland Schoop
- Medical Department, A. Vogel Bioforce AG, Roggwil TG, Switzerland
| | - Andy Suter
- Medical Department, A. Vogel Bioforce AG, Roggwil TG, Switzerland
| | - James Hudson
- Department of Pathology & Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada V6T 2B5
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10
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Saadaoui H, Luo X, Salman Z, Cui XY, Bao NN, Bao P, Zheng RK, Tseng LT, Du YH, Prokscha T, Suter A, Liu T, Wang YR, Li S, Ding J, Ringer SP, Morenzoni E, Yi JB. Intrinsic Ferromagnetism in the Diluted Magnetic Semiconductor Co:TiO_{2}. Phys Rev Lett 2016; 117:227202. [PMID: 27925730 DOI: 10.1103/physrevlett.117.227202] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Indexed: 06/06/2023]
Abstract
Here we present a study of magnetism in Co_{0.05}Ti_{0.95}O_{2-δ} anatase films grown by pulsed laser deposition under a variety of oxygen partial pressures and deposition rates. Energy-dispersive spectrometry and transmission electron microscopy analyses indicate that a high deposition rate leads to a homogeneous microstructure, while a very low rate or postannealing results in cobalt clustering. Depth resolved low-energy muon spin rotation experiments show that films grown at a low oxygen partial pressure (≈10^{-6} torr) with a uniform structure are fully magnetic, indicating intrinsic ferromagnetism. First principles calculations identify the beneficial role of low oxygen partial pressure in the realization of uniform carrier-mediated ferromagnetism. This work demonstrates that Co:TiO_{2} is an intrinsic diluted magnetic semiconductor.
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Affiliation(s)
- H Saadaoui
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - X Luo
- School of Materials Science and Engineering, UNSW, Sydney, New South Wales 2052, Australia
| | - Z Salman
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - X Y Cui
- School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - N N Bao
- Department of Materials Science and Engineering, National University of Singapore, 119260, Singapore
| | - P Bao
- School of Physics, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - R K Zheng
- School of Physics, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - L T Tseng
- School of Materials Science and Engineering, UNSW, Sydney, New South Wales 2052, Australia
| | - Y H Du
- Institute of Chemical and Engineering Science, Agency for Science, Technology and Research (A*STAR), 1 Pesek Road, Jurong Island, 627833, Singapore
| | - T Prokscha
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - A Suter
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - T Liu
- ANKA, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Y R Wang
- School of Materials Science and Engineering, UNSW, Sydney, New South Wales 2052, Australia
| | - S Li
- School of Materials Science and Engineering, UNSW, Sydney, New South Wales 2052, Australia
| | - J Ding
- Department of Materials Science and Engineering, National University of Singapore, 119260, Singapore
| | - S P Ringer
- School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
- The Australian Institute for Nanoscale Science and Technology, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - E Morenzoni
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - J B Yi
- School of Materials Science and Engineering, UNSW, Sydney, New South Wales 2052, Australia
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11
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Anghinolfi L, Luetkens H, Perron J, Flokstra MG, Sendetskyi O, Suter A, Prokscha T, Derlet PM, Lee SL, Heyderman LJ. Thermodynamic phase transitions in a frustrated magnetic metamaterial. Nat Commun 2015; 6:8278. [PMID: 26387444 PMCID: PMC4595626 DOI: 10.1038/ncomms9278] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 08/05/2015] [Indexed: 11/09/2022] Open
Abstract
Materials with interacting magnetic degrees of freedom display a rich variety of magnetic behaviour that can lead to novel collective equilibrium and out-of-equilibrium phenomena. In equilibrium, thermodynamic phases appear with the associated phase transitions providing a characteristic signature of the underlying collective behaviour. Here we create a thermally active artificial kagome spin ice that is made up of a large array of dipolar interacting nanomagnets and undergoes phase transitions predicted by microscopic theory. We use low energy muon spectroscopy to probe the dynamic behaviour of the interacting nanomagnets and observe peaks in the muon relaxation rate that can be identified with the critical temperatures of the predicted phase transitions. This provides experimental evidence that a frustrated magnetic metamaterial can be engineered to admit thermodynamic phases.
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Affiliation(s)
- L Anghinolfi
- Laboratory for Mesoscopic Systems, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland.,Laboratory for Micro- and Nanotechnology, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland.,Laboratory for Neutron Scattering, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - H Luetkens
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - J Perron
- Laboratory for Mesoscopic Systems, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland.,Laboratory for Micro- and Nanotechnology, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland.,Sorbonne Universités, UPMC Univ Paris 06, UMR 7614, LCPMR, 75005 Paris, France.,CNRS, UMR 7614, LCPMR, 75005 Paris, France
| | - M G Flokstra
- School of Physics and Astronomy, SUPA, University of St. Andrews, St. Andrews KY16 9SS, UK
| | - O Sendetskyi
- Laboratory for Mesoscopic Systems, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland.,Laboratory for Micro- and Nanotechnology, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - A Suter
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - T Prokscha
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - P M Derlet
- Condensed Matter Theory Group, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - S L Lee
- School of Physics and Astronomy, SUPA, University of St. Andrews, St. Andrews KY16 9SS, UK
| | - L J Heyderman
- Laboratory for Mesoscopic Systems, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland.,Laboratory for Micro- and Nanotechnology, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
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12
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Saadaoui H, Salman Z, Luetkens H, Prokscha T, Suter A, MacFarlane WA, Jiang Y, Jin K, Greene RL, Morenzoni E, Kiefl RF. The phase diagram of electron-doped La(2-x)Ce(x)CuO(4-δ). Nat Commun 2015; 6:6041. [PMID: 25608106 DOI: 10.1038/ncomms7041] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 12/05/2014] [Indexed: 11/09/2022] Open
Abstract
Superconductivity is a striking example of a quantum phenomenon in which electrons move coherently over macroscopic distances without scattering. The high-temperature superconducting oxides (cuprates) are the most studied class of superconductors, composed of two-dimensional CuO2 planes separated by other layers that control the electron concentration in the planes. A key unresolved issue in cuprates is the relationship between superconductivity and magnetism. Here we report a sharp phase boundary of static three-dimensional magnetic order in the electron-doped superconductor La(2-x)Ce(x)CuO(4-δ), where small changes in doping or depth from the surface switch the material from superconducting to magnetic. Using low-energy spin-polarized muons, we find that static magnetism disappears close to where superconductivity begins and well below the doping level at which dramatic changes in the transport properties are reported. These results indicate a higher degree of symmetry between the electron and hole-doped cuprates than previously thought.
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Affiliation(s)
- H Saadaoui
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - Z Salman
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - H Luetkens
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - T Prokscha
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - A Suter
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - W A MacFarlane
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
| | - Y Jiang
- Center for Nanophysics and Advanced Materials, University of Maryland, College Park, Maryland 20742, USA
| | - K Jin
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - R L Greene
- Center for Nanophysics and Advanced Materials, University of Maryland, College Park, Maryland 20742, USA
| | - E Morenzoni
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - R F Kiefl
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
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13
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Villiger A, Sala F, Suter A, Butterweck V. In vitro inhibitory potential of Cynara scolymus, Silybum marianum, Taraxacum officinale, and Peumus boldus on key enzymes relevant to metabolic syndrome. Phytomedicine 2015; 22:138-44. [PMID: 25636882 DOI: 10.1016/j.phymed.2014.11.015] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 11/17/2014] [Accepted: 11/25/2014] [Indexed: 06/04/2023]
Abstract
Boldocynara®, a proprietary dietary supplement product consisting of the plants Cynara scolymus, Silybum marianum, Taraxacum officinale, and Peumus boldus, used to promote functions of the liver and the gallbladder. It was the aim of the present study to look from a different perspective at the product by investigating the in vitro potential of Boldocynara® as a combination product and its individual extracts on key enzymes relevant to metabolic syndrome. Peumus boldus extract exhibited pronounced inhibitory activities on α-glucosidase (80% inhibition at 100 µg/ml, IC50: 17.56 µg/ml). Silybum marianum had moderate pancreatic lipase (PL) inhibitory activities (30% at 100 µg/ml) whereas Cynara scolymus showed moderate ACE inhibitory activity (31% at 100 µg/ml). The combination had moderate to weak effects on the tested enzymes. In conclusion, our results indicate some moderate potential of the dietary supplement Boldocynara® and its single ingredients for the prevention of metabolic disorders.
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Affiliation(s)
- Angela Villiger
- Institute for Pharma Technology, School of Life Sciences, University of Applied Sciences Northwestern Switzerland, Gründenstrasse 40, CH-4132 Muttenz, Switzerland
| | - Filippo Sala
- Institute for Pharma Technology, School of Life Sciences, University of Applied Sciences Northwestern Switzerland, Gründenstrasse 40, CH-4132 Muttenz, Switzerland
| | - Andy Suter
- Bioforce AG, Grünaustrasse 4, CH-9325 Roggwil, Switzerland
| | - Veronika Butterweck
- Institute for Pharma Technology, School of Life Sciences, University of Applied Sciences Northwestern Switzerland, Gründenstrasse 40, CH-4132 Muttenz, Switzerland.
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14
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Salman Z, Prokscha T, Amato A, Morenzoni E, Scheuermann R, Sedlak K, Suter A. Direct spectroscopic observation of a shallow hydrogenlike donor state in insulating SrTiO3. Phys Rev Lett 2014; 113:156801. [PMID: 25375730 DOI: 10.1103/physrevlett.113.156801] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Indexed: 06/04/2023]
Abstract
We present a direct spectroscopic observation of a shallow hydrogenlike muonium state in SrTiO(3) which confirms the theoretical prediction that interstitial hydrogen may act as a shallow donor in this material. The formation of this muonium state is temperature dependent and appears below ∼ 70K. From the temperature dependence we estimate an activation energy of ∼ 50 meV in the bulk and ∼ 23 meV near the free surface. The field and directional dependence of the muonium precession frequencies further supports the shallow impurity state with a rare example of a fully anisotropic hyperfine tensor. From these measurements we determine the strength of the hyperfine interaction and propose that the muon occupies an interstitial site near the face of the oxygen octahedron in SrTiO(3). The observed shallow donor state provides new insight for tailoring the electronic and optical properties of SrTiO(3)-based oxide interface systems.
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Affiliation(s)
- Z Salman
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
| | - T Prokscha
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
| | - A Amato
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
| | - E Morenzoni
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
| | - R Scheuermann
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
| | - K Sedlak
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
| | - A Suter
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, CH-5232 Villigen PSI, Switzerland
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15
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Hostanska K, Melzer J, Rostock M, Suter A, Saller R. Alteration of anti-inflammatory activity of Harpagophytum procumbens (devil's claw) extract after external metabolic activation with S9 mix. ACTA ACUST UNITED AC 2014; 66:1606-14. [PMID: 25175765 DOI: 10.1111/jphp.12242] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [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: 08/09/2013] [Accepted: 02/02/2014] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Extracts of the tubers of Harpagophytum procumbens (devil's claw, DC) inhibit different proinflammatory mediators important in the pathophysiology of osteoarthritis. Many plant-derived preparations interfere with cytochrome P450 liver enzymes, which influence their different biological activities. Therefore, the present study was designed to investigate the influence of an external metabolic activation of a DC extract on the cytotoxicity and the release of proinflammatory cytokines. METHODS A screening experiment with a panel of 12 inflammatory cytokines identified three as suitable for the study: tumour necrosis factor-α (TNF-α), interleukin (IL) IL-6 and IL-8. They were determined using enzyme-linked immunosorbent assays in lipopolysaccharide (LPS)-stimulated monocytic THP-1 cells, which were treated with rat liver S9 mix metabolically activated DC extract (DCm). For the cytotoxity experiments, a WST-1 assay was used. KEY FINDINGS DC dose-dependently suppressed the release of TNF-α, IL-6 and IL-8 in LPS-stimulated monocytic THP-1 cells at non-cytotoxic concentrations (50-250 μg/ml). The metabolic activation of the DC extract by S9 mix did not alternate its cytotoxicity and did not diminish its inhibitory effect. This effect was improved in the case of TNF-α inhibition as reflected by their EC50 values of 116 ± 8.2 μg/ml and 49 ± 3.5 μg/ml for DC and DCm (P < 0.01). CONCLUSIONS Cytokines inhibitory activity of DC was not affected after its external metabolic activation. However, the amount of harpagoside and caffeic acid derivates was decreased. Other components of the extract might have contributed to its anti-inflammatory effect.
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Affiliation(s)
- Katarina Hostanska
- Institute for Complementary Medicine, University Hospital Zurich, Zurich, Switzerland
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16
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Booker A, Suter A, Krnjic A, Strassel B, Zloh M, Said M, Heinrich M. A phytochemical comparison of saw palmetto products using gas chromatography and (1) H nuclear magnetic resonance spectroscopy metabolomic profiling. J Pharm Pharmacol 2014; 66:811-22. [PMID: 24417505 PMCID: PMC4284019 DOI: 10.1111/jphp.12198] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [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: 06/21/2013] [Accepted: 11/16/2013] [Indexed: 12/03/2022]
Abstract
Objectives Preparations containing saw palmetto berries are used in the treatment of benign prostatic hyperplasia (BPH). There are many products on the market, and relatively little is known about their chemical variability and specifically the composition and quality of different saw palmetto products notwithstanding that in 2000, an international consultation paper from the major urological associations from the five continents on treatments for BPH demanded further research on this topic. Here, we compare two analytical approaches and characterise 57 different saw palmetto products. Methods An established method – gas chromatography – was used for the quantification of nine fatty acids, while a novel approach of metabolomic profiling using 1H nuclear magnetic resonance (NMR) spectroscopy was used as a fingerprinting tool to assess the overall composition of the extracts. Key findings The phytochemical analysis determining the fatty acids showed a high level of heterogeneity of the different products in the total amount and of nine single fatty acids. A robust and reproducible 1H NMR spectroscopy method was established, and the results showed that it was possible to statistically differentiate between saw palmetto products that had been extracted under different conditions but not between products that used a similar extraction method. Principal component analysis was able to determine those products that had significantly different metabolites. Conclusions The metabolomic approach developed offers novel opportunities for quality control along the value chain of saw palmetto and needs to be followed further, as with this method, the complexity of a herbal extract can be better assessed than with the analysis of a single group of constituents.
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Affiliation(s)
- Anthony Booker
- Centre for Pharmacognosy and Phytotherapy, University of London, London, UK
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17
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Huber-Eicher B, Suter A, Spring-Stähli P. Effects of colored light-emitting diode illumination on behavior and performance of laying hens. Poult Sci 2013; 92:869-73. [PMID: 23472008 DOI: 10.3382/ps.2012-02679] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The best method for lighting poultry houses has been an issue for many decades, generating much interest in any new systems that become available. Poultry farmers are now increasingly using colored LED (light-emitting diodes) to illuminate hen houses (e.g., in Germany, Austria, the Netherlands, and England). In Switzerland all newly installed systems are now equipped with LED, preferably green ones. The LED give monochromatic light from different wavelengths and have several advantages over conventional illuminants, including high energy efficiency, long life, high reliability, and low maintenance costs. The following study examines the effects of illumination with white, red, and green LED on behavior and production parameters of laying hens. Light intensities in the 3 treatments were adjusted to be perceived by hens as equal. Twenty-four groups of 25 laying hens were kept in identical compartments (5.0 × 3.3 m) equipped with a litter area, raised perches, feed and drinking facilities, and nest boxes. Initially, they were kept under white LED for a 2-wk adaptation period. For the next 4 wk, 8 randomly chosen compartments were lit with red LED (640 nm) and 8 others with green LED (520 nm). Behavior was monitored during the last 2 wk of the trial. Additionally weight gain, feed consumption, onset of lay, and laying performance were recorded. The results showed minor effects of green light on explorative behavior, whereas red light reduced aggressiveness compared with white light. The accelerating effect of red light on sexual development of laying hens was confirmed, and the trial demonstrated that this effect was due to the specific wavelength and not the intensity of light. However, an additional effect of light intensity may exist and should not be excluded.
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Affiliation(s)
- B Huber-Eicher
- Bern University of Applied Sciences, School of Agricultural, Forest and Food Sciences, Länggasse 85, CH-Zollikofen, Switzerland.
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18
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Prokscha T, Chow KH, Stilp E, Suter A, Luetkens H, Morenzoni E, Nieuwenhuys GJ, Salman Z, Scheuermann R. Photo-induced persistent inversion of germanium in a 200-nm-deep surface region. Sci Rep 2013; 3:2569. [PMID: 23995307 PMCID: PMC3759057 DOI: 10.1038/srep02569] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Accepted: 08/19/2013] [Indexed: 11/17/2022] Open
Abstract
The controlled manipulation of the charge carrier concentration in nanometer thin layers is the basis of current semiconductor technology and of fundamental importance for device applications. Here we show that it is possible to induce a persistent inversion from n- to p-type in a 200-nm-thick surface layer of a germanium wafer by illumination with white and blue light. We induce the inversion with a half-life of ~12 hours at a temperature of 220 K which disappears above 280 K. The photo-induced inversion is absent for a sample with a 20-nm-thick gold capping layer providing a Schottky barrier at the interface. This indicates that charge accumulation at the surface is essential to explain the observed inversion. The contactless change of carrier concentration is potentially interesting for device applications in opto-electronics where the gate electrode and gate oxide could be replaced by the semiconductor surface.
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Affiliation(s)
- T Prokscha
- Paul Scherrer Institute, Laboratory for Muon Spin Spectroscopy, Villigen PSI, Switzerland.
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19
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Charnukha A, Cvitkovic A, Prokscha T, Pröpper D, Ocelic N, Suter A, Salman Z, Morenzoni E, Deisenhofer J, Tsurkan V, Loidl A, Keimer B, Boris AV. Nanoscale layering of antiferromagnetic and superconducting phases in Rb(2)Fe(4)Se(5) single crystals. Phys Rev Lett 2012; 109:017003. [PMID: 23031126 DOI: 10.1103/physrevlett.109.017003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Indexed: 06/01/2023]
Abstract
We studied phase separation in the single-crystalline antiferromagnetic superconductor Rb(2)Fe(4)Se(5) (RFS) using a combination of scattering-type scanning near-field optical microscopy and low-energy muon spin rotation (LE-μSR). We demonstrate that the antiferromagnetic and superconducting phases segregate into nanometer-thick layers perpendicular to the iron-selenide planes, while the characteristic in-plane size of the metallic domains reaches 10 μm. By means of LE-μSR we further show that in a 40-nm thick surface layer the ordered antiferromagnetic moment is drastically reduced, while the volume fraction of the paramagnetic phase is significantly enhanced over its bulk value. Self-organization into a quasiregular heterostructure indicates an intimate connection between the modulated superconducting and antiferromagnetic phases.
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Affiliation(s)
- A Charnukha
- Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany
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20
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Antognini A, Crivelli P, Prokscha T, Khaw KS, Barbiellini B, Liszkay L, Kirch K, Kwuida K, Morenzoni E, Piegsa FM, Salman Z, Suter A. Muonium emission into vacuum from mesoporous thin films at cryogenic temperatures. Phys Rev Lett 2012; 108:143401. [PMID: 22540791 DOI: 10.1103/physrevlett.108.143401] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Indexed: 05/31/2023]
Abstract
We report on muonium (Mu) emission into vacuum following μ(+) implantation in mesoporous thin SiO(2) films. We obtain a yield of Mu into vacuum of (38±4)% at 250 K and (20±4)% at 100 K for 5 keV μ(+) implantation energy. From the implantation energy dependence of the Mu vacuum yield we determine the Mu diffusion constants in these films: D(Mu)(250 K)=(1.6±0.1)×10(-4) cm(2)/s and D(Mu)(100 K)=(4.2±0.5)×10(-5) cm(2)/s. Describing the diffusion process as quantum mechanical tunneling from pore to pore, we reproduce the measured temperature dependence ∼T(3/2) of the diffusion constant. We extract a potential barrier of (-0.3±0.1) eV which is consistent with our computed Mu work function in SiO(2) of [-0.3,-0.9] eV. The high Mu vacuum yield, even at low temperatures, represents an important step toward next generation Mu spectroscopy experiments.
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Affiliation(s)
- A Antognini
- Institute for Particle Physics, ETH Zurich, Switzerland.
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21
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22
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Suter A, Morenzoni E, Prokscha T, Wojek BM, Luetkens H, Nieuwenhuys G, Gozar A, Logvenov G, Božović I. Two-dimensional magnetic and superconducting phases in metal-insulator La(2-x)Sr(x)CuO(4) superlattices measured by muon-spin rotation. Phys Rev Lett 2011; 106:237003. [PMID: 21770540 DOI: 10.1103/physrevlett.106.237003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 03/23/2011] [Indexed: 05/31/2023]
Abstract
We show, by means of low-energy muon-spin rotation measurements, that few-unit-cells thick La(2)CuO(4) layers synthesized digitally by molecular beam epitaxy are antiferromagnetically ordered. Below a thickness of about 5 CuO(2) layers the long-range ordered state breaks down, and a magnetic state appears with enhanced quantum fluctuations and a reduced spin stiffness. This magnetic state can exist in close proximity (few Å) to high-temperature superconducting layers, without transmitting supercurrents.
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Affiliation(s)
- A Suter
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland.
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23
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Abstract
BACKGROUND This trial aimed to assess the tolerability and efficacy of a fresh sage preparation in treating hot flushes and other menopausal complaints. Sage (Salvia officinalis) has been traditionally used to treat sweating and menopausal hot flushes, as well as to alleviate associated menopausal symptoms and as a general tonic. However, no clinical studies substantiating the use of sage in menopause have been published previously. METHODS In an open, multicenter clinical trial conducted in eight practices in Switzerland, 71 patients (intent-to-treat population [ITT], n=69; with a mean age of 56.4±4.7 years, menopausal for at least 12 months, and with at least five flushes daily) were recruited and treated with a once-daily tablet of fresh sage leaves for 8 weeks after an introductory baseline week. Parameters for the evaluation of efficacy were the change in intensity and frequency of hot flushes, and total score of the mean number of intensity-rated hot flushes (TSIRHF) as determined by diary protocol over the 2-month treatment period. Other variables included assessment of the Menopause Rating Scale (MRS) by the treating physician at baseline and after 2 months of therapy. RESULTS In the ITT population there was a significant decrease in the TSIRHF by 50% within 4 weeks and by 64% within 8 weeks (P<0.0001). The mean total number of hot flushes per day decreased significantly each week from week 1 to 8. The mean number of mild, moderate, severe, and very severe flushes decreased by 46%, 62%, 79%, and 100% over 8 weeks, respectively. The MRS and its somato-vegetative, psychological, and urogenital subscales decreased significantly by 43%, 43%, 47%, and 20% respectively. The treatment was very well tolerated. CONCLUSION A fresh sage preparation demonstrated clinical value in the treatment of hot flushes and associated menopausal symptoms.
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Affiliation(s)
- S Bommer
- A. Vogel Bioforce AG, Roggwil, Switzerland.
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24
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Boris AV, Matiks Y, Benckiser E, Frano A, Popovich P, Hinkov V, Wochner P, Castro-Colin M, Detemple E, Malik VK, Bernhard C, Prokscha T, Suter A, Salman Z, Morenzoni E, Cristiani G, Habermeier HU, Keimer B. Dimensionality Control of Electronic Phase Transitions in Nickel-Oxide Superlattices. Science 2011; 332:937-40. [DOI: 10.1126/science.1202647] [Citation(s) in RCA: 296] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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25
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Modarai M, Suter A, Kortenkamp A, Heinrich M. The interaction potential of herbal medicinal products: a luminescence-based screening platform assessing effects on cytochrome P450 and its use with devil's claw (Harpagophyti radix) preparations. J Pharm Pharmacol 2011; 63:429-38. [DOI: 10.1111/j.2042-7158.2010.01235.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Abstract
Objectives
Potential interactions between herbal medicinal products and the cytochrome (CYP) P450 system are an important safety concern. We set out to develop a screening panel for assessing such interactions and use it to evaluate the interaction potential of devil's claw.
Methods
The panel consisted of luminescence-based inhibition assays for CYP1A2, 2C9, 2C19, 2D6 and 3A4, and a reporter gene (luciferase) assay for pregnane X receptor (PXR) activation and CYP3A4 induction. Caftaric acid and chlorogenic acid, two compounds with strong fluorescence quenching properties, were used to demonstrate the assay's resistance to interference. We tested 10 commercial devil's claw preparations as well as harpagoside and harpagide, two important constituents of devil's claw.
Key findings
Five preparations were found to weakly inhibit CYP3A4 (IC50 124.2–327.6 µg/ml) and five were found to weakly activate PXR (EC50 10.21–169.3 µg/ml). Harpagoside and harpagide did not inhibit CYP3A4. In agreement with published data, bergamottin, a natural product known to interact with CYP3A4, was shown to inhibit CYP3A4 with an IC50 of 13.63 µm and activate PXR with an EC50 of 6.7 µm.
Conclusions
Devil's claw preparations are unlikely to have a clinically relevant effect on CYP function. The assay panel proved effective in screening devil's claw preparations, demonstrating its suitability for use with plant extracts. It showed superior sensitivity and resistance to interference.
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Affiliation(s)
- Maryam Modarai
- Centre for Pharmacognosy and Phytotherapy, University of London, London, UK
- Centre for Toxicology, The School of Pharmacy, University of London, London, UK
| | | | - Andreas Kortenkamp
- Centre for Toxicology, The School of Pharmacy, University of London, London, UK
| | - Michael Heinrich
- Centre for Pharmacognosy and Phytotherapy, University of London, London, UK
- Southern Cross Plant Science, Centre for Phytochemistry and Pharmacology, Southern Cross University, Lismore, NSW, Australia
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26
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Schulz L, Nuccio L, Willis M, Desai P, Shakya P, Kreouzis T, Malik VK, Bernhard C, Pratt FL, Morley NA, Suter A, Nieuwenhuys GJ, Prokscha T, Morenzoni E, Gillin WP, Drew AJ. Engineering spin propagation across a hybrid organic/inorganic interface using a polar layer. Nat Mater 2011; 10:39-44. [PMID: 21131962 DOI: 10.1038/nmat2912] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2010] [Accepted: 10/28/2010] [Indexed: 05/30/2023]
Abstract
Spintronics has shown a remarkable and rapid development, for example from the initial discovery of giant magnetoresistance in spin valves to their ubiquity in hard-disk read heads in a relatively short time. However, the ability to fully harness electron spin as another degree of freedom in semiconductor devices has been slower to take off. One future avenue that may expand the spintronic technology base is to take advantage of the flexibility intrinsic to organic semiconductors (OSCs), where it is possible to engineer and control their electronic properties and tailor them to obtain new device concepts. Here we show that we can control the spin polarization of extracted charge carriers from an OSC by the inclusion of a thin interfacial layer of polar material. The electric dipole moment brought about by this layer shifts the OSC highest occupied molecular orbital with respect to the Fermi energy of the ferromagnetic contact. This approach allows us full control of the spin band appropriate for charge-carrier extraction, opening up new spintronic device concepts for future exploitation.
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Affiliation(s)
- L Schulz
- Department of Physics and Fribourg Center for Nanomaterials, University of Fribourg, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
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Modarai M, Silva E, Suter A, Heinrich M, Kortenkamp A. Safety of Herbal Medicinal Products: Echinacea and Selected Alkylamides Do Not Induce CYP3A4 mRNA Expression. Evid Based Complement Alternat Med 2010; 2011:213021. [PMID: 19906827 PMCID: PMC3095427 DOI: 10.1093/ecam/nep174] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2009] [Accepted: 10/02/2009] [Indexed: 12/11/2022]
Abstract
A major safety concern with the use of herbal medicinal products (HMP) is their interactions with conventional medicines, which are often mediated via the cytochrome P450 (CYP) system. Echinacea is a widely used over-the-counter HMP, with proven immunomodulatory properties. Its increasing use makes research into its safety an urgent concern. Previously, we showed that Echinacea extracts and its alkylamides (thought to be important for Echinacea's immunomodulatory activity) mildly inhibit the enzymatic activity of the main drug metabolising CYP isoforms, but to this date, there is insufficient work on its ability to alter CYP expression levels. We now report for the first time the effect of a commercial Echinacea extract (Echinaforce) and four Echinacea alkylamides on the transcription of the major drug metabolizing enzyme CYP3A4. HepG2 cells were exposed for 96 h to clinically relevant concentrations of Echinaforce (22, 11.6 and 1.16 μg mL(-1)) or the alkylamides (1.62 and 44 nM). CYP3A4 mRNA levels were quantified using real-time reverse transcription polymerase chain reaction (RT-PCR). Neither Echinaforce nor the alkylamides produced any significant changes in the steady-state CYP3A4 mRNA levels, under these conditions. In contrast, treatment with 50 μM rifampicin resulted in a 3.8-fold up-regulation over the vehicle control. We conclude that Echinaforce is unlikely to affect CYP3A4 transcriptional levels, even at concentrations which can inhibit the enzymatic activity of CYP3A4. Overall, our data provides further evidence for the lack of interactions between Echinacea and conventional drugs.
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Affiliation(s)
- Maryam Modarai
- Centre for Pharmacognosy and Phytotherapy, The School of Pharmacy, University of London, 29/39 Brunswick Square, London, WC1N 1AX, UK
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Sharma M, Schoop R, Suter A, Hudson JB. The potential use of Echinacea in acne: control of Propionibacterium acnes growth and inflammation. Phytother Res 2010; 25:517-21. [PMID: 20830697 DOI: 10.1002/ptr.3288] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Revised: 07/18/2010] [Accepted: 08/02/2010] [Indexed: 11/10/2022]
Abstract
Acne is a chronic inflammatory disorder of skin follicles caused by the gram-positive bacterium Propionibacterium acnes. The possibility was investigated that a standardized preparation of Echinacea purpurea (Echinaforce®), with known antiviral, antiinflammatory and antibacterial properties, might provide a useful alternative treatment in the control of the disease. The herbal extract readily killed a standard laboratory strain of the bacterium and several clinical isolates. In cell culture models of human bronchial epithelial cells and skin fibroblasts, P. acne induced the secretion of substantial amounts of several pro-inflammatory cytokines, including IL-6 and IL-8 (CXCL8), as determined by means of cytokine-antibody arrays. However, the E. purpurea completely reversed this effect and brought the cytokine levels back to normal. Thus Echinaforce® could provide a safe two-fold benefit to acne individuals by inhibiting proliferation of the organism and reversing the bacterial-induced inflammation.
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Affiliation(s)
- M Sharma
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, Canada
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29
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Woelkart K, Feizlmayr E, Dittrich P, Beubler E, Pinl F, Suter A, Bauer R. Pharmacokinetics of bilobalide, ginkgolide A and B after administration of three different Ginkgo biloba L. preparations in humans. Phytother Res 2010; 24:445-50. [PMID: 20041430 DOI: 10.1002/ptr.3074] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A sensitive LC-ESI-MS method with a solid-phase extraction was established for the determination of bilobalide, ginkgolide A and ginkgolide B in human plasma; bioavailability and pharmacokinetics of three different Ginkgo biloba L. preparations have been investigated. The preparations used in the present single-dose pharmacokinetic study were different formulations of Ginkgo biloba L. extracts (Geriaforce tincture, new Ginkgo fresh plant extract tablets and EGb 761) with various excipients. The analysis of Ginkgo terpene lactones was performed by LC-MS on a Zorbax SB-C18 column. The mobile phase consisted of water + 0.1% acetic acid and methanol 68/32 (v/v) to 49/51 (v/v) at a flow rate of 200 microL/min. Bilobalide, ginkgolide A and ginkgolide B were monitored using the selected-ion monitoring (SIM) mode at m/z of 325, 453 and 423, respectively.The amounts of the active compounds (terpene lactones) in the administered products were in the low-mg range per dose. The assay method was successfully applied to the study of the pharmacokinetics and bioavailability of bilobalide, ginkgolide A and ginkgolide B in humans. The resulting maximum concentrations (median) of bilobalide, ginkgolide A and ginkgolide B in plasma after administration of the maximum daily dose of the different Ginkgo products were 3.53, 3.62, and 1.38 ng/mL respectively after administration of Geriaforce tincture; 11.68, 7.36, and 4.18 ng/mL, respectively after taking Ginkgo fresh plant extract tablets; and 26.85, 16.44, 9.99 ng/mL, respectively after administration of EGb 761 tablets. These data are relevant to demonstrate relative bioavailabilities of different Ginkgo biloba L. preparations (Geriaforce tincture, new Ginkgo fresh plant extract tablets and EGb 761).
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Affiliation(s)
- Karin Woelkart
- Institute of Pharmaceutical Sciences, Department of Pharmacognosy, Karl-Franzens-University Graz, 8010 Graz, Austria
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Dunsiger SR, Carlo JP, Goko T, Nieuwenhuys G, Prokscha T, Suter A, Morenzoni E, Chiba D, Nishitani Y, Tanikawa T, Matsukura F, Ohno H, Ohe J, Maekawa S, Uemura YJ. Spatially homogeneous ferromagnetism of (Ga, Mn)As. Nat Mater 2010; 9:299-303. [PMID: 20305642 DOI: 10.1038/nmat2715] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Accepted: 01/28/2010] [Indexed: 05/29/2023]
Abstract
Mn-doped GaAs is a ferromagnetic semiconductor, widely studied because of its possible application for spin-sensitive 'spintronics' devices. The material also attracts great interest in fundamental research regarding its evolution from a paramagnetic insulator to a ferromagnetic metal. The high sensitivity of its physical properties to preparation conditions and heat treatments and the strong doping and temperature dependencies of the magnetic anisotropy have generated a view in the research community that ferromagnetism in (Ga, Mn)As may be associated with unavoidable and intrinsic strong spatial inhomogeneity. Muon spin relaxation (muSR) probes magnetism, yielding unique information about the volume fraction of regions having static magnetic order, as well as the size and distribution of the ordered moments. By combining low-energy muSR, conductivity and a.c. and d.c. magnetization results obtained on high-quality thin-film specimens, we demonstrate here that (Ga, Mn)As shows a sharp onset of ferromagnetic order, developing homogeneously in the full volume fraction, in both insulating and metallic films. Smooth evolution of the ordered moment size across the insulator-metal phase boundary indicates strong ferromagnetic coupling between Mn moments that exists before the emergence of fully itinerant hole carriers.
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Modarai M, Yang M, Suter A, Kortenkamp A, Heinrich M. Metabolomic profiling of liquid Echinacea medicinal products with in vitro inhibitory effects on cytochrome P450 3A4 (CYP3A4). Planta Med 2010; 76:378-385. [PMID: 19790031 DOI: 10.1055/s-0029-1186152] [Citation(s) in RCA: 22] [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] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
ECHINACEA is a popular and widely used herbal medicinal product and consequently, studies of its interactions with conventional drugs are of particular importance. We have shown that ECHINACEA preparations and some common alkylamides weakly inhibit several cytochrome P450 (CYP) isoforms, with considerable variation in potency. We now report a detailed analysis of six commercial ECHINACEA liquid preparations, with emphasis on the metabolomic characterisation of the ECHINACEA compounds responsible for inhibiting CYP3A4. We separated each preparation into its ethanol- and water-soluble components, and then used (1)H-NMR together with multivariate data analysis and partial least square regression analysis to investigate the nature of the compounds responsible for CYP3A4 inhibition. The results implicated alkylamides in the CYP3A4 inhibitory activity of ECHINACEA. One of the commercial preparations (Echinaforce(R)) was further fractionated using solid phase extraction. Analysis by (1)H-NMR and mass spectroscopy (LC/MS, tandem MS, accurate mass) identified dodeca-2 E,4 E,8 Z,10 E/Z-tetraenoic acid (alkylamide 1) and a new compound (putative molecular formula C (18)H (36) NO (+)) as major components of the inhibitory fractions. In addition, the alkylamide content of all six preparations was determined by reverse phase HPLC. Levels of alkylamides 1 and 3 (undeca-2 E,4 E/ Z-diene-8,10-diynoic acid isobutylamide), correlated well with CYP3A4 inhibition. The acetylene tetradeca-8 Z-ene-11,13-diyn-2-one was shown to be present in the E. PURPUREA as well as the E. PALLIDA extracts. E. PURPUREA unlike E. PALLIDA was thought to not contain significant amounts of acetylenes. Our results directly confirm the role of alkylamides in the inhibition of CYP3A4 by ECHINACEA and uncovered a new compound which may also be involved. Extensive differences in the composition of the commercially available preparations were found. This will inevitably impact on the product efficacy, safety and pharmacological effects, especially since the differences involve alkylamides, an important class of ECHINACEA's active constituents. The metabolomic approach presented here may prove valuable as a screening or quality control tool.
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Affiliation(s)
- Maryam Modarai
- Centre for Pharmacognosy and Phytotherapy, The School of Pharmacy, University of London, London, UK
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Modarai M, Gertsch J, Suter A, Heinrich M, Kortenkamp A. Cytochrome P450 inhibitory action of Echinacea preparations differs widely and co-varies with alkylamide content. J Pharm Pharmacol 2010; 59:567-73. [PMID: 17430641 DOI: 10.1211/jpp.59.4.0012] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [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: 10/31/2022]
Abstract
Abstract
Echinacea preparations are one of the best selling herbal medicinal products with a well established therapeutic use in the prophylaxis of upper respiratory tract infections. Their consumption is increasing, but information about their ability to inhibit cytochrome P450 enzymes (CYP) is fragmentary. The picture is further complicated by a lack of phytochemical characterization of previously tested preparations. Due to its well characterized immunomodulatory activity, the standardized Swiss registered Echinacea purpurea (L.) Moench Echinaforce extract was selected for detailed study. With the single baculovirus-expressed CYP isoforms 1A2, 2C19, 2D9 and 3A4, inhibitory actions were measured by monitoring fluorescent metabolites derived from enzyme substrates (supersome assay). The Echinaforce extract induced mild inhibition of all these isoforms, with CYP 3A4 being the most, and CYP 2D6 the least sensitive enzyme. To assess whether CYP inhibition might be a general feature of Echinacea preparations, an additional nine commercially available preparations were screened using CYP 3A4. All tested preparations were able to inhibit CYP 3A4, but inhibitory potencies (expressed as median inhibitory concentration, IC50) varied by a factor of 150. The alkylamides are thought to be responsible for the immunomodulatory activity of Echinacea, and so the concentration of 2E,4E,8Z,10E/Z-tetranoic acid isobutylamide (1) and total alkylamide content were determined in all preparations, and the latter was found to be associated with their CYP 3A4 inhibitory potency. The chemically pure alkylamides dodeca-2E,4E,8Z,10E/Z-tetranoic acid isobutylamide (1) and dodeca-2E,4E-dieonoic acid isobutylamide (2) showed inhibitory activity on CYP 2C19, 2D6 and 3A4. However, unlike the Echinaforce extract, the alkylamides did not induce CYP 1A2 inhibition. Thus, other, as yet unidentified constituents also contribute to the overall weak inhibitory effects seen with Echinacea preparations in-vitro.
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Affiliation(s)
- M Modarai
- Centre for Pharmacognosy and Phytotherapy, The School of Pharmacy, University of London, 29/39 Brunswick Square, London WC1N 1AX, UK
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Abstract
Background The aim of this trial was to assess the relative efficacy of a sage/echinacea spray and a chlorhexidine/lidocaine spray in the treatment of acute sore throats. Methods This was a multicenter, randomized, double-blind, double-dummy controlled trial carried out in eleven general practices in Switzerland. A total of 154 patients (133 analyzed in per protocol collective) at least 12 years old with acute sore throat present for not more than 72 hours prior to inclusion and with a throat score ≥6 participated in the study. They used either an echinacea/sage spray or a chlorhexidine/lidocaine spray with two puffs every 2 hours, in a double-dummy blinded manner, up to 10 times daily until they were symptom-free, for a maximum of 5 days. The main outcome measures was the comparison of response rates during the first three days. A response was defined as a decrease of at least 50% of the total symptoms compared to baseline. Results The echinacea/sage treatment exhibited similar efficacy to the chlorhexidine/lidocaine treatment in reducing sore throat symptoms during the first 3 days (P(x < Y) = .5083). Response rates after 3 days were 63.8% in the echinacea/sage group and 57.8% in the chlorhexidine/lidocaine group. For all secondary parameters, such as time to becoming symptom free, throat pain, and global assessments of efficacy by the physician and patient, no difference between the two treatments was seen. They were both very well tolerated. Conclusion An echinacea/sage preparation is as efficacious and well tolerated as a chlorhexidine/lidocaine spray in the treatment of acute sore throats.
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Dickson S, Gallagher J, McIntyre L, Suter A, Tan J. An Open Study to Assess the Safety and Efficacy ofAesculus hippocastanumTablets (Aesculaforce® 50 mg) in the Treatment of Chronic Venous Insufficiency. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/j157v04n02_03] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Drew AJ, Hoppler J, Schulz L, Pratt FL, Desai P, Shakya P, Kreouzis T, Gillin WP, Suter A, Morley NA, Malik VK, Dubroka A, Kim KW, Bouyanfif H, Bourqui F, Bernhard C, Scheuermann R, Nieuwenhuys GJ, Prokscha T, Morenzoni E. Direct measurement of the electronic spin diffusion length in a fully functional organic spin valve by low-energy muon spin rotation. Nat Mater 2009; 8:109-114. [PMID: 19029892 DOI: 10.1038/nmat2333] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2008] [Accepted: 10/21/2008] [Indexed: 05/27/2023]
Abstract
Electronic devices that use the spin degree of freedom hold unique prospects for future technology. The performance of these 'spintronic' devices relies heavily on the efficient transfer of spin polarization across different layers and interfaces. This complex transfer process depends on individual material properties and also, most importantly, on the structural and electronic properties of the interfaces between the different materials and defects that are common to real devices. Knowledge of these factors is especially important for the relatively new field of organic spintronics, where there is a severe lack of suitable experimental techniques that can yield depth-resolved information about the spin polarization of charge carriers within buried layers of real devices. Here, we present a new depth-resolved technique for measuring the spin polarization of current-injected electrons in an organic spin valve and find the temperature dependence of the measured spin diffusion length is correlated with the device magnetoresistance.
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Affiliation(s)
- A J Drew
- Department of Physics and Fribourg Center for Nanomaterials, University of Fribourg, Chemin du Musée 3, CH-1700 Fribourg, Switzerland.
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36
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Bäurle P, Suter A, Wormstall H. Safety and Effectiveness of a Traditional Ginkgo Fresh Plant Extract – Results from a Clinical Trial. ACTA ACUST UNITED AC 2009; 16:156-61. [DOI: 10.1159/000213167] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Suter A. Ueber die Aetiologie und Pathogenese der Pachymeningitis haemorrhagica interna und ihre Beziehungen zu einer B 1-Hypovitaminose; pp. 257–275. Eur Neurol 2008. [DOI: 10.1159/000148282] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Suter A. Ueber die Aetiologie und Pathogenese der Pachymeningitis haemorrhagica interna und ihre Beziehungen zu einer B 1-Hypovitaminose; pp. 276–295. Eur Neurol 2008. [DOI: 10.1159/000148283] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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39
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Haeusler M, Hogan C, Juneja S, Bartlett J, Suter A. New Transport System for Maintaining Temperature of Blood Products in Emergency Situations. Transfus Med 2008. [DOI: 10.1111/j.1365-3148.2005.00554s.x] [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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Dimpfel W, Suter A. Sleep improving effects of a single dose administration of a valerian/hops fluid extract - a double blind, randomized, placebo-controlled sleep-EEG study in a parallel design using electrohypnograms. Eur J Med Res 2008; 13:200-204. [PMID: 18559301 DOI: 10.1055/s-2008-1047853] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [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: 05/24/2023] Open
Abstract
Repetitive administrations of valerian/hops combinations have been widely used for self-administered therapy of sleep disturbances. This investigation focuses on the question if a single administration can be an effective sleep aid. Two parallel groups of n = 20 (verum) and n = 22 (placebo) were tested. Each subject spent two consecutive nights in the lab (reference night and medication night). Medication consisted in giving verum or placebo to poor sleepers identified by a validated sleep questionnaire (Schlaffragebogen SF-B). Two ml of the liquid ex?tract or similar smelling placebo were diluted in 50 ml water (flavoured with honey) and administered 15 minutes before EEG recording during the medication night. The data analysis is based on the electrohypnogram - a method derived from a validated computer assisted automatic analysis for depth of sleep. Differences between the reference nights and medication nights were evaluated and tested for significance. Time spent in sleep (values of the sleep frequency index "SFx" of the electrohypnogram of 74% or lower) was significantly higher for the verum group in comparison to the placebo group (p<0.01). The difference with respect to time spent in deeper sleep (i.e. 68% and lower or 62% and lower) between reference and medication night was also statistically significant at p<0.01. This parameter correlated with the difference in quality of sleep between the two consecutive nights as derived from the sleep inventory SF-A sub-score (subjects evaluation) with r = 0.48 at p<0.0001. The EEG derived parameter "sleep quantity" as calculated from the electrohypnogram proved superiority of the valerian/hops combination over placebo. Thus, the present investigation has shown evidence that a valerian/hops fluid extract can be used successfully using a single administration.
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Affiliation(s)
- Wilfried Dimpfel
- Justus-Liebig-University Giessen, c/o NeuroCode AG, Sportparkstr. 9, 35578 Wetzlar, Germany.
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41
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Woelkart K, Dittrich P, Beubler E, Pinl F, Schoop R, Suter A, Bauer R. Pharmacokinetics of the main alkamides after administration of three different Echinacea purpurea preparations in humans. Planta Med 2008; 74:651-6. [PMID: 18240099 DOI: 10.1055/s-2008-1034284] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Establishing the pharmacological basis for efficacy of herbal medicinal products (HMPs) is a continuous challenge. In this context, also the question of bioavailability, the elucidation of metabolic pathways and their pharmacokinetics is of major interest. These data are relevant to link results from pharmacological IN VITRO assays and clinical studies. A better understanding of the pharmacokinetics and bioavailability of phytopharmaceuticals can also help in designing rational dosage regimes. The preparations used in the present pharmacokinetic single-dose study are different ECHINACEA PURPUREA formulations (Echinaforce) with various excipients. The concentrations of the active compounds (alkamides) in the administered products have been in the low mg range per dose. Due to the expected necessary detection of ng ranges, a sensitive and selective LC-ESI-MS-based method that is capable of monitoring plasma levels of traces of active constituents in humans was developed and validated. The resulting maximum concentrations (mean +/- standard deviation) of dodeca-2 E,4 E,8 Z, 10 E/ Z-tetraenoic acid isobutylamides in plasma were 0.22 +/- 0.07 ng/mL after administration of Echinaforce tablets, 0.22 +/- 0.15 ng/mL after taking Echinaforce Junior tablets and 0.23 +/- 0.16 ng/mL after administration of an Echinacea sore throat spray. The areas under the curve were 0.22 ng/mL x h, 0.20 ng/mL x h and 0.23 ng/mL x h, respectively.
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Affiliation(s)
- Karin Woelkart
- Institute of Pharmaceutical Sciences, Department of Pharmacognosy, Karl-Franzens-University, Graz, Austria
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Morenzoni E, Luetkens H, Prokscha T, Suter A, Vongtragool S, Galli F, Hesselberth MBS, Garifianov N, Khasanov R. Depth-dependent spin dynamics of canonical spin-glass films: a low-energy muon-spin-rotation study. Phys Rev Lett 2008; 100:147205. [PMID: 18518070 DOI: 10.1103/physrevlett.100.147205] [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] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Revised: 02/01/2008] [Indexed: 05/26/2023]
Abstract
We have performed depth dependent muon-spin-rotation and -relaxation studies of the dynamics of single layer films of AuFe and CuMn spin glasses as a function of thickness and of its behavior as a function of distance from the vacuum interface (5-70 nm). A significant reduction in the muon-spin relaxation rate as a function of temperature with respect to the bulk material is observed when the muons are stopped near (5-10 nm) the surface of the sample. A similar reduction is observed for the whole sample if the thickness is reduced to, e.g., 20 nm and less. This reflects an increased impurity spin dynamics (incomplete freezing) close to the surface although the freezing temperature is only modestly affected by the dimensional reduction.
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Affiliation(s)
- E Morenzoni
- Paul Scherrer Institut, Labor für Myon-Spin Spektroskopie, CH-5232 Villigen PSI, Switzerland.
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Prokscha T, Morenzoni E, Eshchenko DG, Garifianov N, Glückler H, Khasanov R, Luetkens H, Suter A. Formation of hydrogen impurity States in silicon and insulators at low implantation energies. Phys Rev Lett 2007; 98:227401. [PMID: 17677876 DOI: 10.1103/physrevlett.98.227401] [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] [Subscribe] [Scholar Register] [Received: 07/13/2006] [Indexed: 05/16/2023]
Abstract
The formation of hydrogenlike muonium (Mu) has been studied as a function of implantation energy in intrinsic Si, thin films of condensed van der Waals gases (N2, Ne, Ar, Xe), fused and crystalline quartz, and sapphire. By varying the initial energy of positive muons (mu+) between 1 and 30 keV the number of electron-hole pairs generated in the ionization track of the mu+ can be tuned between a few and several thousand. The results show the strong suppression of the formation of those Mu states that depend on the availability of excess electrons. This indicates that the role of H-impurity states in determining electric properties of semiconductors and insulators depends on the way in which atomic H is introduced into the material.
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Affiliation(s)
- T Prokscha
- Paul Scherrer Institut, Labor für Myon-Spin Spektroskopie, CH-5232 Villigen PSI, Switzerland.
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Hostanska K, Suter A, Melzer J, Saller R. Evaluation of cell death caused by an ethanolic extract of Serenoae repentis fructus (Prostasan) on human carcinoma cell lines. Anticancer Res 2007; 27:873-81. [PMID: 17465214] [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: 05/15/2023]
Abstract
BACKGROUND Phytotherapy is a third approach for treating lower urinary tract symptoms associated with benign prostatic hyperplasia (BPH). The lipido-sterolic extract of the fruit of Serenoa repens is one of the more widely used phytotherapeutic agents in this regard. MATERIALS AND METHODS The effect of an ethanolic extract of S. repens (10-1000 microg/ml) was tested in hormone-sensitive LNCaP, MCF-7 and hormone-insensitive DU 145, MDA MB231 prostate, breast carcinoma cell lines, renal Caki-1, urinary bladder J82, colon HCT 116 and lung A 549 cancer cells. Its cell growth inhibitory and apoptosis-inducing effects were tested using WST-1 assay and flow cytometry (Annexin V/PI stain) and/or by colorimetric assay (APOPercentage assay). RESULTS The S. repens extract induced a dose-dependent antiproliferative effect on all human malignant cells tested, with GI50 values between 107 and 327 pmicro/ml. In hormone-sensitive prostate LNCaP and breast MCF-7 cell lines, the effect of extract expressed in GI50 was 2.2- and 2.5-fold more potent (p < 0.01) than in hormone-insensitive DU 145 and MDA MB231 cells. The proportion of apoptotic cells, except in A549 cells, lay between 22.5-36.3%. S. repens extract did not induce apoptosis in lung cancer A 549 cells. CONCLUSION This study showed that the antiproliferative effect exerted by the ethanolic extract of S. repens is at least triggered by induction of apoptosis. These in vitro data provide some information that may be useful for clinical use and render S. repens extract an interesting tool for new applications.
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Affiliation(s)
- Katarina Hostanska
- University Hospital Zurich, Department of Internal Medicine, Institute for Complementary Medicine, Rämistrasse 100, 8091 Zurich, Switzerland.
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Widrig R, Suter A, Saller R, Melzer J. Choosing between NSAID and arnica for topical treatment of hand osteoarthritis in a randomised, double-blind study. Rheumatol Int 2007; 27:585-91. [PMID: 17318618 DOI: 10.1007/s00296-007-0304-y] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2006] [Accepted: 12/26/2006] [Indexed: 10/23/2022]
Abstract
The use of topical preparations for symptom relief is common in osteoarthritis. The effects of ibuprofen (5%) and arnica (50 g tincture/100 g, DER 1:20), as gel preparations in patients with radiologically confirmed and symptomatically active osteoarthritis of interphalangeal joints of hands, were evaluated in a randomised, double-blind study in 204 patients, to ascertain differences in pain relief and hand function after 21 days' treatment. Diagnosis was according to established criteria; primary endpoints were pain intensity and hand function; statistical design was as per current regulatory guidelines for testing topical preparations. There were no differences between the two groups in pain and hand function improvements, or in any secondary end points evaluated. Adverse events were reported by six patients (6.1%) on ibuprofen and by five patients (4.8%) on arnica. Our results confirm that this preparation of arnica is not inferior to ibuprofen when treating osteoarthritis of hands.
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Affiliation(s)
- Reto Widrig
- Rheumatology Clinic, 9004, St Gallen, Switzerland
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Woelkart K, Marth E, Suter A, Schoop R, Raggam RB, Koidl C, Kleinhappl B, Bauer R. Bioavailability and pharmacokinetics of Echinacea purpurea preparations and their interaction with the immune system. Int J Clin Pharmacol Ther 2007; 44:401-8. [PMID: 16995328 DOI: 10.5414/cpp44401] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [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: 11/18/2022] Open
Abstract
Echinacea is a widely used herbal remedy for the prevention and treatment of the common cold. Recently, many new insights concerning the molecular mode of action of the main lipophilic constituents, the alkamides, have renewed interest in this plant. In order to compare the bioavailability of alkamides from liquid and tablet preparations of E. purpurea (Echinaforce) in humans and to study the effects on ex vivo stimulated blood cells, a randomized, single-dose, crossover study with 10 (8 test, 2 placebo) volunteers has been performed. They received either 4 ml of the standardized E. purpurea (Echinaforce) tincture or 12 E. purpurea (Echinaforce) tablets or placebo. Both doses contained the same amount (0.07 mg) of the major alkamides, dodeca-2E,4E,8Z, 10E/Z-tetraenoic acid isobutylamides. Liquid chromatography electrospray ionization ion-trap mass spectrometry was used to determine the content of alkamides in serum. It was found that the arithmetic mean C(max) of dodeca-2E,4E, 8Z,10E/Z-tetraenoic acid isobutylamides absorbed after oral application of the Echinaforce tincture appeared after 30 min (0.40 ng/ml serum). In comparison, the t(max) of tablets was 45 min with a C(max) of 0.12 ng/ml. An ex vivo stimulation of blood by LPS was carried out to measure the influence of E. purpurea on the innate and adaptive immune system. Both E. purpurea preparations led to the same effects on the immune system according to the concentration of pro-inflammatory cytokines TNF-alpha and IL-8. 23 hours after oral application a significant down-regulation of TNF-alpha and IL-8 in LPS pre-stimulated whole blood was found. However, no significant changes in the concentration of IL-6 were observed. Although a quarter of the dodeca-2E,4E,8Z, 10E/Z-tetraenoic acid isobutylamides was absorbed from the tablets, the study shows that the formulations trigger the same effects on the measured immune parameters.
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Affiliation(s)
- K Woelkart
- Institute of Pharmaceutical Sciences, Department of Pharmacognosy, Karl Franzens University, Graz, Austria
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Abstract
This open, multicenter study investigated the tolerability and efficacy of a new tablet formulation of Echinacea purpurea extract (Echinaforce Forte; A. Vogel, Bioforce AG, Roggwil, Switzerland) in 80 subjects actively involved in sports. Most investigators (97.5%) rated the treatment as having "very good" or "good" tolerability. About 75% of patients and investigators rated its efficacy during a common cold as "very good" or "good," and 71% of subjects were free of cold episodes. This study is the first to suggest that Echinaforce is effective in the prophylaxis, as well as the treatment, of the common cold in persons who actively participate in sports.
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Morenzoni E, Khasanov R, Luetkens H, Prokscha T, Suter A. Surface and thin film studies with polarized low energy muons. Journal of Neutron Research 2006. [DOI: 10.1080/10238160600975432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Abstract
BACKGROUND The therapeutic effectiveness of Echinacea in the treatment and the prevention of colds has been debated. Studies of naturally occurring colds are hampered by variability in time from onset of symptoms to treatment and by heterogeneity in trial design. Experimental infection studies allow for the standardization of time to initiation of treatment, virus type and dose, and immune competence of volunteers. OBJECTIVE To determine whether the negative results obtained in previous studies of Echinacea were a consequence of efficacy or of inadequate sample size, we performed a meta-analysis of experimental rhinovirus infection studies on the efficacy of Echinacea extracts to prevent symptomatic development of an experimentally induced cold. METHODS We carried out a systematic search of English- and German-language literature using the MEDLINE, EMBASE, CAplus, BIOSIS, CABA, AGRICOLA, TOXCENTER, SCISEARCH, NAHL, and NAPRALERT, databases and the search terms Echinacea, black Sampson, coneflower, and Roter Sonnenbut. Matching documents were then searched for > or = 1 of the following terms: rhinovirus, RV, inoculation, Inokulation, induced, induziert, artificial, and artifiziell. Suitable studies were identified and pooled for analysis. The primary end point was the development of symptomatic clinical colds, as defined by the authors of the original studies. Results were reported as differences in the proportion of subjects with symptomatic episodes of a common cold, expressed as odds ratios (ORs) and 95% CIs. The secondary outcome was the difference in total symptom severity scores between treatment groups (assessed daily by integrating the severity scores of 8 individual cold-related symptoms that were rated on a scale from 0 [absent] to 4 [very severe]). RESULTS A total of 234 articles were identified through the literature search; 231 were excluded from the analysis because they related to studies of spontaneous common colds. Three suitable studies were selected for pooling of data. Based on the analysis, the likelihood of experiencing a clinical cold was 55% higher with placebo than with Echinacea (OR, 1.55 [95% CI, 1.02-2.36]; P<0.043). The absolute difference in total symptom scores between groups was -1.96 (95% CI, -4.83 to 0.90; P=NS). CONCLUSIONS This meta-analysis suggests that standardized extracts of Echinacea were effective in the prevention of symptoms of the common cold after clinical inoculation, compared with placebo. Further prospective, appropriately powered clinical studies are required to confirm this finding.
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Suter A, Bommer S, Rechner J. Treatment of patients with venous insufficiency with fresh plant horse chestnut seed extract: a review of 5 clinical studies. Adv Ther 2006; 23:179-90. [PMID: 16644618 DOI: 10.1007/bf02850359] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [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: 12/01/2022]
Abstract
Extracts from the seed of the horse chestnut (Aesculus hippocastanum L.) have traditionally been used to treat patients with chronic venous insufficiency and to alleviate its associated symptoms, including lower leg swelling. The efficacy of preparations that contain horse chestnut seed extract (HCSE) is believed to be due largely to an inhibitory effect on the catalytic breakdown of capillary wall proteoglycans. Aesculaforce is a fresh plant HCSE that is available as an oral tincture, as tablets (20 mg or 50 mg), and as topical gel. Four clinical trials in patients with chronic venous insufficiency and 1 study in patients with varicose veins demonstrated the effectiveness of these preparations through the objective measure of reduction in lower leg edema and the subjective alleviation of leg pain, heaviness, and itching. Safe, well tolerated, and acceptable to patients, the fresh plant HCSE preparation Aesculaforce offers a real alternative in the treatment of patients with mild to moderate venous insufficiency.
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Affiliation(s)
- Andy Suter
- Medical Department, Bioforce AG, Roggwil, Switzerland
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