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Heiße F, Door M, Sailer T, Filianin P, Herkenhoff J, König CM, Kromer K, Lange D, Morgner J, Rischka A, Schweiger C, Tu B, Novikov YN, Eliseev S, Sturm S, Blaum K. High-Precision Determination of g Factors and Masses of ^{20}Ne^{9+} and ^{22}Ne^{9+}. Phys Rev Lett 2023; 131:253002. [PMID: 38181339 DOI: 10.1103/physrevlett.131.253002] [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: 05/24/2023] [Revised: 08/11/2023] [Accepted: 09/05/2023] [Indexed: 01/07/2024]
Abstract
We present the measurements of individual bound electron g factors of ^{20}Ne^{9+} and ^{22}Ne^{9+} on the relative level of 0.1 parts per billion. The comparison with theory represents the most stringent test of bound-state QED in strong electric fields. A dedicated mass measurement results in m(^{20}Ne)=19.992 440 168 77(9) u, which improves the current literature value by a factor of 18, disagrees by 4 standard deviations, and represents the most precisely measured mass value in atomic mass units. Together, these measurements yield an electron mass on the relative level of 0.1 ppb with m_{e}=5.485 799 090 99(59)×10^{-4} u as well as a factor of seven improved m(^{22}Ne)=21.991 385 098 2(26) u.
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Affiliation(s)
- F Heiße
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - M Door
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - T Sailer
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - P Filianin
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - J Herkenhoff
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - C M König
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - K Kromer
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - D Lange
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - J Morgner
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - A Rischka
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - Ch Schweiger
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - B Tu
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - Y N Novikov
- Kurchatov Institute-PNPI, 188300 Gatchina, Russia
- Saint Petersburg State University, 199034 Saint Petersburg, Russia
| | - S Eliseev
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - S Sturm
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - K Blaum
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
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2
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Morgner J, Tu B, König CM, Sailer T, Heiße F, Bekker H, Sikora B, Lyu C, Yerokhin VA, Harman Z, Crespo López-Urrutia JR, Keitel CH, Sturm S, Blaum K. Stringent test of QED with hydrogen-like tin. Nature 2023; 622:53-57. [PMID: 37794267 PMCID: PMC10550826 DOI: 10.1038/s41586-023-06453-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 07/19/2023] [Indexed: 10/06/2023]
Abstract
Inner-shell electrons naturally sense the electric field close to the nucleus, which can reach extreme values beyond 1015 V cm-1 for the innermost electrons1. Especially in few-electron, highly charged ions, the interaction with the electromagnetic fields can be accurately calculated within quantum electrodynamics (QED), rendering these ions good candidates to test the validity of QED in strong fields. Consequently, their Lamb shifts were intensively studied in the past several decades2,3. Another approach is the measurement of gyromagnetic factors (g factors) in highly charged ions4-7. However, so far, either experimental accuracy or small field strength in low-Z ions5,6 limited the stringency of these QED tests. Here we report on our high-precision, high-field test of QED in hydrogen-like 118Sn49+. The highly charged ions were produced with the Heidelberg electron beam ion trap (EBIT)8 and injected into the ALPHATRAP Penning-trap setup9, in which the bound-electron g factor was measured with a precision of 0.5 parts per billion (ppb). For comparison, we present state-of-the-art theory calculations, which together test the underlying QED to about 0.012%, yielding a stringent test in the strong-field regime. With this measurement, we challenge the best tests by means of the Lamb shift and, with anticipated advances in the g-factor theory, surpass them by more than an order of magnitude.
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Affiliation(s)
- J Morgner
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany.
| | - B Tu
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - C M König
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - T Sailer
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - F Heiße
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - H Bekker
- Helmholtz-Institut Mainz, GSI Helmholtzzentrum für Schwerionenforschung, Mainz, Germany
| | - B Sikora
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - C Lyu
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - V A Yerokhin
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - Z Harman
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | | | - C H Keitel
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - S Sturm
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
| | - K Blaum
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
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3
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Sasidharan S, Bezrodnova O, Rau S, Quint W, Sturm S, Blaum K. Penning-Trap Mass Measurement of Helium-4. Phys Rev Lett 2023; 131:093201. [PMID: 37721828 DOI: 10.1103/physrevlett.131.093201] [Citation(s) in RCA: 1] [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: 04/04/2023] [Accepted: 08/04/2023] [Indexed: 09/20/2023]
Abstract
Light-ion trap (LIONTRAP), a high-precision Penning-trap mass spectrometer, was used to determine the atomic mass of ^{4}He. Here, we report a 12 parts-per-trillion measurement of the mass of a ^{4}He^{2+} ion, m(^{4}He^{2+})=4.001 506 179 651(48) u. From this, the atomic mass of the neutral atom can be determined without loss of precision: m(^{4}He)=4.002 603 254 653(48) u. This result is slightly more precise than the current CODATA18 literature value but deviates by 6.6 standard deviations.
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Affiliation(s)
- S Sasidharan
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, 64291 Darmstadt, Germany
- Heidelberg University, Grabengasse 1, 69117 Heidelberg, Germany
| | - O Bezrodnova
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - S Rau
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - W Quint
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, 64291 Darmstadt, Germany
| | - S Sturm
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - K Blaum
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
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4
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Jordie EB, Gibiansky L, Knab T, Lemenuel-Diot A, Ravva P, Zwanziger E, Jolivet S, Bhardwaj R, Hernández-Sánchez J, Nasmyth-Miller C, Sturm S. Dosing regimen optimisation for oseltamivir in immunocompromised paediatric patients with influenza: Extrapolation of efficacy. Br J Clin Pharmacol 2021; 88:1189-1201. [PMID: 34449090 DOI: 10.1111/bcp.15059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 08/12/2021] [Accepted: 08/16/2021] [Indexed: 11/29/2022] Open
Abstract
AIMS To optimise the dosing regimen of oseltamivir for immunocompromised (IC) paediatric patients (<18 years) with influenza, we used an extrapolation approach alongside clinical data. METHODS Efficacy was extrapolated from adult IC patients to paediatric IC patients by leveraging existing efficacy, safety, pharmacokinetic (PK)/pharmacodynamic (PD), and disease-progression models of oseltamivir and oseltamivir carboxylate (OC). Data of IC paediatric patients from two studies (NV25719 and NV20234) were included in the population PK (n = 30), PK/PD analysis (n = 22) and disease modelling approach (n = 36). Simulations were performed to identify the optimal dosing regimen. RESULTS Clearance of oseltamivir (CL) and OC (CLM ) were similar in IC and otherwise-healthy (OwH) patients <10 years, but decreased by 44.4% (95% CI: 26.8-62.0) and 49.1% (95% CI: 34.5-63.8), respectively, in IC patients aged 10-17 years versus OwH patients. There were no notable exposure-response relationships for any of the virologic PD analyses. Thus, no additional benefit was seen with oseltamivir carboxylate exposures higher than achieved with the conventional dose (75 mg twice daily, age- and weight-adjusted for children <13 years). The disease model illustrated that doses above the conventional oseltamivir dose had limited impact on viral kinetics in IC paediatric patients and a prolonged treatment duration of 10 days was favoured to limit potential viral rebound. CONCLUSION An oseltamivir dosage recommendation (conventional dose, twice daily for 10 days) was established in IC paediatric patients with influenza, based on extrapolation of efficacy from IC adults, leveraging population PK, PK/PD, and disease modelling, whilst taking resistance and safety data into account.
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Affiliation(s)
- Eric Burroughs Jordie
- Translational & Systems Pharmacology, Metrum Research Group LLC, Tariffville, CT, USA
| | | | - Timothy Knab
- Translational & Systems Pharmacology, Metrum Research Group LLC, Tariffville, CT, USA
| | - Annabelle Lemenuel-Diot
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Basel, Switzerland
| | - Patanjali Ravva
- Roche Innovation Center New York, Roche Pharmaceutical Research and Early Development, New York, NY, USA
| | - Elke Zwanziger
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Basel, Switzerland
| | - Sebastien Jolivet
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Basel, Switzerland
| | - Rajinder Bhardwaj
- Integrated Drug Development, Certara Strategic Consulting, Parsippany, NJ, USA
| | | | | | - Stefan Sturm
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Basel, Switzerland
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5
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Filianin P, Lyu C, Door M, Blaum K, Huang WJ, Haverkort M, Indelicato P, Keitel CH, Kromer K, Lange D, Novikov YN, Rischka A, Schüssler RX, Schweiger C, Sturm S, Ulmer S, Harman Z, Eliseev S. Direct Q-Value Determination of the β^{-} Decay of ^{187}Re. Phys Rev Lett 2021; 127:072502. [PMID: 34459634 DOI: 10.1103/physrevlett.127.072502] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 06/01/2021] [Accepted: 07/08/2021] [Indexed: 06/13/2023]
Abstract
The cyclotron frequency ratio of ^{187}Os^{29+} to ^{187}Re^{29+} ions was measured with the Penning-trap mass spectrometer PENTATRAP. The achieved result of R=1.000 000 013 882(5) is to date the most precise such measurement performed on ions. Furthermore, the total binding-energy difference of the 29 missing electrons in Re and Os was calculated by relativistic multiconfiguration methods, yielding the value of ΔE=53.5(10) eV. Finally, using the achieved results, the mass difference between neutral ^{187}Re and ^{187}Os, i.e., the Q value of the β^{-} decay of ^{187}Re, is determined to be 2470.9(13) eV.
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Affiliation(s)
- P Filianin
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - C Lyu
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - M Door
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - K Blaum
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - W J Huang
- Advanced Energy Science and Technology Guangdong Laboratory, Huizhou 516003, China
| | - M Haverkort
- Institute for Theoretical Physics, Heidelberg University, 69120 Heidelberg, Germany
| | | | - C H Keitel
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - K Kromer
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - D Lange
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - Y N Novikov
- Department of Physics, St Petersburg State University, St Petersburg 198504, Russia
- NRC "Kurchatov Institute"-Petersburg Nuclear Physics Institute, Gatchina 188300, Russia
| | - A Rischka
- ARC Centre for Engineered Quantum Systems, School of Physics, The University of Sydney, NSW 2006, Australia
| | - R X Schüssler
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - Ch Schweiger
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - S Sturm
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - S Ulmer
- Ulmer Fundamental Symmetries Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
| | - Z Harman
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - S Eliseev
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
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6
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Sturm S, Lemenuel-Diot A, Patel K, Gibiansky L, Bhardwaj R, Smith PF, Dang S, Zwanziger E, Nasmyth-Miller C, Ravva P. Pharmacologic effects of oseltamivir in immunocompromised adult patients as assessed by population PK/PD analysis and drug-disease modelling for dosing regimen optimization. Br J Clin Pharmacol 2020; 87:1359-1368. [PMID: 32808306 PMCID: PMC8246794 DOI: 10.1111/bcp.14523] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [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: 02/12/2020] [Revised: 07/29/2020] [Accepted: 08/04/2020] [Indexed: 01/04/2023] Open
Abstract
Aim Pharmacologic effects were analysed to determine a dose recommendation for oseltamivir in immunocompromised (IC) adults with influenza. Methods Quantitative clinical pharmacology methods were applied to data from 160 adult IC patients (aged 18‐78 years) from two studies (NV20234, 150 patients; NV25118, 10 patients) who received oseltamivir 75‐200 mg twice daily for up to 10 days. An established population‐pharmacokinetic (PK) model with additional effects on oseltamivir and oseltamivir carboxylate (OC) clearance described the PK characteristics of oseltamivir in IC patients versus otherwise healthy (OwH) patients from previous clinical trials. Estimated PK parameters were used to evaluate exposure‐response relationships for virologic endpoints (time to cessation of viral shedding, viral load measures and treatment‐emergent resistance). A drug‐disease model characterized the viral kinetics of influenza accounting for the effect of OC on viral production. Results Oseltamivir clearance was 32.5% lower (95% confidence interval [CI], 26.1‐38.8) and OC clearance was 33.7% lower (95% CI, 23.2‐44.1) in IC versus OwH patients. No notable exposure‐response relationships were identified for exposures higher than those achieved after conventional dose oseltamivir 75 mg, which appeared to be close to the maximum effect of oseltamivir. Simulations of the drug‐disease model predicted that initiating treatment within 48 hours of symptom onset had maximum impact, and a treatment duration of 10 days was favourable over 3‐5 days to limit viral rebound. Conclusions Our findings support the use of conventional‐dose oseltamivir 75 mg twice daily for 10 days in the treatment of IC adult patients with influenza.
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Affiliation(s)
- Stefan Sturm
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Basel, Switzerland
| | - Annabelle Lemenuel-Diot
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Basel, Switzerland
| | | | | | | | | | - Steve Dang
- Roche Innovation Center New York, Roche Pharmaceutical Research and Early Development, New York, NY, USA
| | - Elke Zwanziger
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Basel, Switzerland
| | | | - Patanjali Ravva
- Roche Innovation Center New York, Roche Pharmaceutical Research and Early Development, New York, NY, USA
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7
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Gibiansky L, Ravva P, Parrott NJ, Bhardwaj R, Zwanziger E, Grimsey P, Clinch B, Sturm S. Mechanistic Population Pharmacokinetic Model of Oseltamivir and Oseltamivir Carboxylate Accounting for Physiological Changes to Predict Exposures in Neonates and Infants. Clin Pharmacol Ther 2020; 108:126-135. [PMID: 31957010 PMCID: PMC7325316 DOI: 10.1002/cpt.1791] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [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: 10/10/2019] [Accepted: 01/04/2020] [Indexed: 11/12/2022]
Abstract
A mechanistic population‐pharmacokinetic model was developed to predict oseltamivir exposures in neonates and infants accounting for physiological changes during the first 2 years of life. The model included data from 13 studies, comprising 436 subjects with normal renal function (317 pediatric subjects (≥ 38 weeks postmenstrual age (PMA), ≥ 13 days old) and 119 adult subjects < 40 years). Concentration–time profiles of oseltamivir and its active metabolite, oseltamivir carboxylate (OC), were characterized by a four‐compartment model, with absorption described by three additional compartments. Renal maturational changes were implemented by description of OC clearance with allometric function of weight and Hill function of PMA. Clearance of OC increased with weight up to 43 kg (allometric coefficient 0.75). Half the adult OC clearance was reached at a PMA of 45.6 weeks (95% confidence interval (CI) 41.6–49.6) with a Hill coefficient of 2.35 (95% CI 1.67–3.04). The model supports the European Union/United States‐approved 3 mg/kg twice‐daily oseltamivir dose for infants < 1 year (PMA ≥ 38 weeks) and allows prediction of exposures in preterm neonates.
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Affiliation(s)
| | - Patanjali Ravva
- Roche Innovation Center New York, Roche Pharmaceutical Research and Early Development, New York, New York, USA.,Pfizer Inc, Global Clinical Pharmacology, New York, New York, USA
| | - Neil J Parrott
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Basel, Switzerland
| | - Rajinder Bhardwaj
- Integrated Drug Development, Certara Strategic Consulting, Parsippany, New Jersey, USA
| | - Elke Zwanziger
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Basel, Switzerland
| | - Paul Grimsey
- Roche Innovation Center Welwyn, Roche Pharmaceutical Research and Early Development, Welwyn Garden City, UK
| | - Barry Clinch
- Roche Products Limited, Product Development, Welwyn Garden City, UK
| | - Stefan Sturm
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Basel, Switzerland
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8
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Glazov DA, Köhler-Langes F, Volotka AV, Blaum K, Heiße F, Plunien G, Quint W, Rau S, Shabaev VM, Sturm S, Werth G. g Factor of Lithiumlike Silicon: New Challenge to Bound-State QED. Phys Rev Lett 2019; 123:173001. [PMID: 31702246 DOI: 10.1103/physrevlett.123.173001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 08/31/2019] [Indexed: 06/10/2023]
Abstract
The recently established agreement between experiment and theory for the g factors of lithiumlike silicon and calcium ions manifests the most stringent test of the many-electron bound-state quantum electrodynamics (QED) effects in the presence of a magnetic field. In this Letter, we present a significant simultaneous improvement of both theoretical g_{th}=2.000 889 894 4 (34) and experimental g_{exp}=2.000 889 888 45 (14) values of the g factor of lithiumlike silicon ^{28}Si^{11+}. The theoretical precision now is limited by the many-electron two-loop contributions of the bound-state QED. The experimental value is accurate enough to test these contributions on a few percent level.
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Affiliation(s)
- D A Glazov
- Department of Physics, St. Petersburg State University, Universitetskaya 7/9, 199034 St. Petersburg, Russia
| | - F Köhler-Langes
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - A V Volotka
- Department of Physics, St. Petersburg State University, Universitetskaya 7/9, 199034 St. Petersburg, Russia
- Helmholtz-Institut Jena, Fröbelstieg 3, D-07743 Jena, Germany
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, D-64291 Darmstadt, Germany
| | - K Blaum
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - F Heiße
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, D-64291 Darmstadt, Germany
| | - G Plunien
- Institut für Theoretische Physik, Technische Universität Dresden, Mommsenstraße 13, D-01062 Dresden, Germany
| | - W Quint
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, D-64291 Darmstadt, Germany
| | - S Rau
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - V M Shabaev
- Department of Physics, St. Petersburg State University, Universitetskaya 7/9, 199034 St. Petersburg, Russia
| | - S Sturm
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg, Germany
| | - G Werth
- Institut für Physik, Johannes Gutenberg-Universität, D-55099 Mainz, Germany
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9
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Bautista F, Engelhard D, Rizzari C, Baka M, Saavedra-Lozano J, Lopez-Medina E, Nasmyth-Miller C, Hernández-Sánchez J, Sturm S. Pharmacokinetics and Pharmacodynamics of Conventional-Dose vs Triple-Dose Oseltamivir in Severely Immunocompromised Children With Influenza. Open Forum Infect Dis 2019; 6:ofz430. [PMID: 31660381 PMCID: PMC6809794 DOI: 10.1093/ofid/ofz430] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 09/25/2019] [Indexed: 11/28/2022] Open
Abstract
This randomized phase 1b study evaluated the pharmacokinetics/pharmacodynamics of conventional-dose (30–75 mg twice daily [BID]) vs triple-dose (90–225 mg BID; weight-adjusted) oseltamivir for treatment of influenza in severely immunocompromised children <13 years. Oseltamivir carboxylate (OC) Cmax and AUC0-12h were ~2-fold higher with triple-dose vs conventional-dose oseltamivir. Increased dose/exposure of oseltamivir/OC did not improve virological outcomes or reduce viral resistance. Median time to cessation of viral shedding was similar with triple-dose and conventional-dose oseltamivir (150.7 vs 157.1 hours, respectively); median time to alleviation of baseline fever was longer with conventional-dose oseltamivir (28.4 vs 11.3 hours). No new safety signals were identified.
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Affiliation(s)
- Francisco Bautista
- Pediatric Hematology, Oncology and Stem Cell Transplantation Department, Hospital Infantil Universitario Niño Jesús, Madrid, Spain
| | - Dan Engelhard
- Department of Pediatrics, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Carmelo Rizzari
- Pediatric Hematology-Oncology Unit, Department of Pediatrics, MBBM Foundation, ASST-Monza, University of Milano-Bicocca, Monza, Italy
| | - Margarita Baka
- Department of Pediatric Oncology, Aglaia Kyriakou Children's Hospital, Athens, Greece
| | - Jesús Saavedra-Lozano
- Infectious Disease Unit, Department of Pediatrics, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Eduardo Lopez-Medina
- Department of Pediatrics, Universidad del Valle, Centro Médico Imbanaco and Centro de Estudios en Infectología Pediátrica, Cali, Colombia
| | | | | | - Stefan Sturm
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Basel, Switzerland
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10
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Arapoglou I, Egl A, Höcker M, Sailer T, Tu B, Weigel A, Wolf R, Cakir H, Yerokhin VA, Oreshkina NS, Agababaev VA, Volotka AV, Zinenko DV, Glazov DA, Harman Z, Keitel CH, Sturm S, Blaum K. g Factor of Boronlike Argon ^{40}Ar^{13+}. Phys Rev Lett 2019; 122:253001. [PMID: 31347869 DOI: 10.1103/physrevlett.122.253001] [Citation(s) in RCA: 10] [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: 02/22/2019] [Revised: 04/26/2019] [Indexed: 06/10/2023]
Abstract
We have measured the ground-state g factor of boronlike argon ^{40}Ar^{13+} with a fractional uncertainty of 1.4×10^{-9} with a single ion in the newly developed Alphatrap double Penning-trap setup. The value of g=0.663 648 455 32(93) obtained here is in agreement with our theoretical prediction of 0.663 648 12(58). The latter is obtained accounting for quantum electrodynamics, electron correlation, and nuclear effects within the state-of-the-art theoretical methods. Our experimental result distinguishes between existing predictions that are in disagreement, and lays the foundations for an independent determination of the fine-structure constant.
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Affiliation(s)
- I Arapoglou
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - A Egl
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - M Höcker
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - T Sailer
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - B Tu
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - A Weigel
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - R Wolf
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - H Cakir
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - V A Yerokhin
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
- Peter the Great St. Petersburg Polytechnic University, 195251 St. Petersburg, Russia
| | - N S Oreshkina
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - V A Agababaev
- St. Petersburg State University, 199034 St. Petersburg, Russia
- St. Petersburg Electrotechnical University, 197376 St. Petersburg, Russia
| | - A V Volotka
- St. Petersburg State University, 199034 St. Petersburg, Russia
- Helmholtz-Institut Jena, 07743 Jena, Germany
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - D V Zinenko
- St. Petersburg State University, 199034 St. Petersburg, Russia
| | - D A Glazov
- St. Petersburg State University, 199034 St. Petersburg, Russia
| | - Z Harman
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - C H Keitel
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - S Sturm
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
| | - K Blaum
- Max-Planck-Institut für Kernphysik, 69117 Heidelberg, Germany
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Bogman K, Brumm J, Hofmann C, Giraudon M, Niggli M, Sturm-Pellanda C, Sauter A, Sturm S, Mangold B, Schmitt C. Assessment of Drug–Drug Interactions between Taspoglutide, a Glucagon-Like Peptide-1 Agonist, and Drugs Commonly Used in Type 2 Diabetes Mellitus: Results of Five Phase I Trials. Clin Pharmacokinet 2019; 58:1205-1214. [DOI: 10.1007/s40262-019-00757-1] [Citation(s) in RCA: 1] [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: 12/25/2022]
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12
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Sturm S, Günther A, Jaber B, Jordan P, Al Kotbi N, Parkar N, Cleary Y, Frances N, Bergauer T, Heinig K, Kletzl H, Marquet A, Ratni H, Poirier A, Müller L, Czech C, Khwaja O. A phase 1 healthy male volunteer single escalating dose study of the pharmacokinetics and pharmacodynamics of risdiplam (RG7916, RO7034067), a SMN2 splicing modifier. Br J Clin Pharmacol 2018; 85:181-193. [PMID: 30302786 DOI: 10.1111/bcp.13786] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [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: 03/23/2018] [Revised: 08/29/2018] [Accepted: 09/09/2018] [Indexed: 12/22/2022] Open
Abstract
AIMS Risdiplam (RG7916, RO7034067) is an orally administered, centrally and peripherally distributed, survival of motor neuron 2 (SMN2) mRNA splicing modifier for the treatment of spinal muscular atrophy (SMA). The objectives of this entry-into-human study were to assess the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics of risdiplam, and the effect of the strong CYP3A inhibitor itraconazole on the PK of risdiplam in healthy male volunteers. METHODS Part 1 had a randomized, double-blind, adaptive design with 25 subjects receiving single ascending oral doses of risdiplam (ranging from 0.6-18.0 mg, n = 18) or placebo (n = 7). A Bayesian framework was applied to estimate risdiplam's effect on SMN2 mRNA. The effect of multiple doses of itraconazole on the PK of risdiplam was also assessed using a two-period cross-over design (n = 8). RESULTS Risdiplam in the fasted or fed state was well tolerated. Risdiplam exhibited linear PK over the dose range with a multi-phasic decline with a mean terminal half-life of 40-69 h. Food had no relevant effect, and itraconazole had only a minor effect on plasma PK indicating a low fraction of risdiplam metabolized by CYP3A. The highest tested dose of 18.0 mg risdiplam led to approximately 41% (95% confidence interval 27-55%) of the estimated maximum increase in SMN2 mRNA. CONCLUSIONS Risdiplam was well tolerated and proof of mechanism was demonstrated by the intended shift in SMN2 splicing towards full-length SMN2 mRNA. Based on these data, Phase 2/3 studies of risdiplam in patients with SMA are now ongoing.
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Kletzl H, Czech C, Cleary Y, Sturm S, Günther A, Baranello G, Mercuri E, Servais L, Day J, Deconinck N, Klein A, Darras B, Masson R, Kirschner J, Goemans N, Pera M, Chiriboga C, Fischer D, Gorni K, Khwaja O. SMA THERAPIES II AND BIOMARKERS. Neuromuscul Disord 2018. [DOI: 10.1016/j.nmd.2018.06.307] [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: 11/16/2022]
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Micke P, Kühn S, Buchauer L, Harries JR, Bücking TM, Blaum K, Cieluch A, Egl A, Hollain D, Kraemer S, Pfeifer T, Schmidt PO, Schüssler RX, Schweiger C, Stöhlker T, Sturm S, Wolf RN, Bernitt S, Crespo López-Urrutia JR. The Heidelberg compact electron beam ion traps. Rev Sci Instrum 2018; 89:063109. [PMID: 29960545 DOI: 10.1063/1.5026961] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Electron beam ion traps (EBITs) are ideal tools for both production and study of highly charged ions (HCIs). In order to reduce their construction, maintenance, and operation costs, we have developed a novel, compact, room-temperature design, the Heidelberg Compact EBIT (HC-EBIT). Four already commissioned devices operate at the strongest fields (up to 0.86 T) reported for such EBITs using permanent magnets, run electron beam currents up to 80 mA, and energies up to 10 keV. They demonstrate HCI production, trapping, and extraction of pulsed Ar16+ bunches and continuous 100 pA ion beams of highly charged Xe up to charge state 29+, already with a 4 mA, 2 keV electron beam. Moreover, HC-EBITs offer large solid-angle ports and thus high photon count rates, e.g., in x-ray spectroscopy of dielectronic recombination in HCIs up to Fe24+, achieving an electron-energy resolving power of E/ΔE > 1500 at 5 keV. Besides traditional on-axis electron guns, we have also implemented a novel off-axis gun for laser, synchrotron, and free-electron laser applications, offering clear optical access along the trap axis. We report on its first operation at a synchrotron radiation facility demonstrating the resonant photoexcitation of highly charged oxygen.
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Affiliation(s)
- P Micke
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - S Kühn
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - L Buchauer
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - J R Harries
- National Institutes for Quantum and Radiological Science and Technology, SPring-8, Kouto 1-1-1, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - T M Bücking
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - K Blaum
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - A Cieluch
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - A Egl
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - D Hollain
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - S Kraemer
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - T Pfeifer
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - P O Schmidt
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany
| | - R X Schüssler
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - Ch Schweiger
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - T Stöhlker
- GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291 Darmstadt, Germany
| | - S Sturm
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - R N Wolf
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - S Bernitt
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
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Sturm S, Delporte ML, Hadi S, Schobel S, Lindemann L, Weikert R, Jaeschke G, Derks M, Palermo G. Results and evaluation of a first-in-human study of RG7342, an mGlu5 positive allosteric modulator, utilizing Bayesian adaptive methods. Br J Clin Pharmacol 2017; 84:445-455. [PMID: 29096426 DOI: 10.1111/bcp.13466] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 10/12/2017] [Accepted: 10/21/2017] [Indexed: 12/13/2022] Open
Abstract
AIM The objectives of this first-in-human study were to evaluate the safety and tolerability, pharmacokinetics and pharmacodynamics, and maximum tolerated dose (MTD) of single ascending oral doses of RG7342, a positive allosteric modulator (PAM) of the metabotropic glutamate receptor 5 (mGlu5) for the treatment of schizophrenia, in healthy male subjects. METHODS This was a single-centre, randomized, double-blind, adaptive study of 37 subjects receiving single ascending oral doses of RG7342 (ranging from 0.06-1.2 mg, n = 27) or placebo (n = 10). A modified continual reassessment method, with control for the probability of overdosing based on the occurrence of dose-limiting events (DLEs), was applied to inform the subsequent dose decisions for RG7342. RESULTS DLEs consisted of dizziness, nausea and vomiting, and the incidence and severity of these adverse events increased in a concentration-dependent manner. RG7342 doses of 1.2 mg under fasting conditions, which reached a mean maximum plasma concentration (Cmax ) of 10.2 ng ml-1 , were not tolerated (four out of six subjects experienced DLEs). RG7342 showed dose-proportional pharmacokinetics, with rapid absorption and a biphasic decline, and a mean terminal half-life estimated to be >1000 h. CONCLUSIONS Single oral doses of RG7342 were generally tolerated up to 0.6 mg under fasting and 0.9 mg under fed conditions in healthy subjects. Bayesian adaptive methods describing the probability of DLEs were applied effectively to support dose escalation. MTDs (fasting, fed) were associated with a Cmax of 6.5 ng ml-1 . The development of RG7342 was discontinued owing to the potential challenges associated with a long half-life in context of the observed adverse events.
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Affiliation(s)
- Stefan Sturm
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland
| | - Marie-Laure Delporte
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland
| | - Salah Hadi
- PRA Health Sciences (PRA) - Early Development Services, Van Swietenlaan 6 Clinical Site, Groningen, the Netherlands
| | - Scott Schobel
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland
| | - Lothar Lindemann
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland
| | - Robert Weikert
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland
| | - Georg Jaeschke
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland
| | - Michael Derks
- Roche Innovation Center Welwyn, Roche Pharmaceutical Research and Early Development, 6 Falcon Way, Welwyn Garden City, UK
| | - Giuseppe Palermo
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland
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Mercuri E, Kirschner J, Baranello G, Servais L, Goemans N, Pera M, Marquet A, Seabrook T, Sturm S, Armstrong G, Kletzl H, Czech C, Kraus D, Abdallah H, Mueller L, Gorni K, Khwaja O. Clinical studies of RG7916 in patients with spinal muscular atrophy: SUNFISH part 1 study update. Neuromuscul Disord 2017. [DOI: 10.1016/j.nmd.2017.06.415] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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17
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Immohr LI, Dischinger A, Kühl P, Kletzl H, Sturm S, Günther A, Pein-Hackelbusch M. Early pediatric formulation development with new chemical entities: Opportunities of e-tongue besides human taste assessment. Int J Pharm 2017; 530:201-212. [PMID: 28750893 DOI: 10.1016/j.ijpharm.2017.07.069] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 07/19/2017] [Accepted: 07/21/2017] [Indexed: 10/19/2022]
Abstract
The palatability of a pediatric drug formulation is one of the key prerequisites for therapeutic success. Liquid formulations are often chosen for pediatric drug products, and they require special attention regarding their taste, as they have direct contact to the taste buds and a relatively long residence time in the oral cavity. For ethical reasons, the role of electronic tongues in the development of oral drug formulations with new chemical entities (NCEs) for pediatric use is growing, however, little is known about the strategies how this instrumental taste assessment can be performed. The present study illustrates two possibilities to combine in-vitro and in-vivo data for the characterization of the palatability of the new drug candidates CSE3104 and CSE3165. As a first step, the implementation and suitability of electronic tongue measurements has been demonstrated by comparison of in-vivo and in-vitro data. In alignment with the taste assessment results during a single-center, double-blinded, randomized, placebo-controlled, single ascending dose (SAD) study in healthy subjects, the bitter taste perception of CSE3104 was assessed with e-tongue measurements. Moreover, the sensor response pattern showed comparable results of the e-tongue measurements to the human taste study of CSE3165: With increasing concentration, the bitterness values were increased. In addition, the human taste pattern showed increasing values for sourness due to higher volumes of the citric acid buffer. Results of the hedonic descriptor "unpleasant" within the human taste assessments could be related to bitterness in the instrumental taste assessment. For the second step in electronic tongue guided formulation development two possibilities are depicted in the article focusing on the effect of different excipients on the formulation on the one hand and on the assessment and comparison of two drug formulations on the other hand. Based on these results, the low number of healthy volunteers for the taste assessment in a Phase 1 study led to a meaningful interpretation, by applying in addition the electronic tongue. Using this instrumental approach led to reproducible data versus the human taste assessment, without ethical concerns, and with a reduction in time and costs.
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Affiliation(s)
- Laura Isabell Immohr
- Institute of Pharmaceutics and Biopharmaceutics, Heinrich-Heine-University Duesseldorf, Universitaetsstr. 1, 40225, Duesseldorf, Germany
| | - Angela Dischinger
- Formulation Research and Development, F. Hoffmann-La Roche Ltd, Basel, Switzerland
| | - Peter Kühl
- Formulation Research and Development, F. Hoffmann-La Roche Ltd, Basel, Switzerland
| | | | - Stefan Sturm
- Clinical Pharmacology, F. Hoffmann-La Roche Ltd, Basel, Switzerland
| | - Andreas Günther
- Clinical Pharmacology, F. Hoffmann-La Roche Ltd, Basel, Switzerland
| | - Miriam Pein-Hackelbusch
- Life Science Technologies, University of Applied Sciences Ostwestfalen-Lippe, Georg-Weerth-Strasse 20, 32756 Detmold, Germany.
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Heiße F, Köhler-Langes F, Rau S, Hou J, Junck S, Kracke A, Mooser A, Quint W, Ulmer S, Werth G, Blaum K, Sturm S. High-Precision Measurement of the Proton's Atomic Mass. Phys Rev Lett 2017; 119:033001. [PMID: 28777624 DOI: 10.1103/physrevlett.119.033001] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Indexed: 06/07/2023]
Abstract
We report on the precise measurement of the atomic mass of a single proton with a purpose-built Penning-trap system. With a precision of 32 parts per trillion our result not only improves on the current CODATA literature value by a factor of 3, but also disagrees with it at a level of about 3 standard deviations.
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Affiliation(s)
- F Heiße
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, 64291 Darmstadt, Germany
| | - F Köhler-Langes
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - S Rau
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - J Hou
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - S Junck
- Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz, Germany
| | - A Kracke
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - A Mooser
- RIKEN, Ulmer Fundamental Symmetries Laboratory, Wako, Saitama 351-0198, Japan
| | - W Quint
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, 64291 Darmstadt, Germany
| | - S Ulmer
- RIKEN, Ulmer Fundamental Symmetries Laboratory, Wako, Saitama 351-0198, Japan
| | - G Werth
- Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz, Germany
| | - K Blaum
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
| | - S Sturm
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
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Giraudon M, Sturm S, Lambert N, Niggli M, Brumm J, Mangold B, Schmitt C. Effect of varying degrees of renal impairment on the pharmacokinetics and tolerability of taspoglutide. Diabetes Obes Metab 2017; 19:537-544. [PMID: 27981717 DOI: 10.1111/dom.12850] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 12/01/2016] [Accepted: 12/08/2016] [Indexed: 11/30/2022]
Abstract
AIM To evaluate single-dose pharmacokinetics and tolerability of taspoglutide in people with varying degrees of renal impairment and matched healthy participants. METHODS Participants in the present study were people with mild renal impairment (n = 10), moderate impairment (n = 10), severe impairment (n = 9), and a matched healthy control group (n = 10). Participants received a single subcutaneous injection of taspoglutide (10 mg) on day 1. Plasma and urine drug concentration, antibody formation, vital signs, ECGs and routine laboratory variables were measured frequently and adverse events (AEs) were monitored for 9 weeks. RESULTS Taspoglutide exposure was higher among participants with moderate and severe renal impairment compared with participants with normal renal function. Mean AUClast was 13% and 38% higher in participants with moderate and severe renal impairment, respectively compared with participants with normal renal function. Likewise, mean peak plasma concentration (Cmax ) was 57% and 93% higher in participants with moderate and severe renal function impairment, respectively, compared with participants with normal renal function. Linear regression analyses showed a statistically significant inverse relationship between taspoglutide exposure parameters (AUC and Cmax ) and creatinine clearance. Higher incidences of gastrointestinal (GI) AEs were reported in participants with severe renal impairment. CONCLUSION Renal impairment altered the pharmacokinetics of taspoglutide. The degree of renal impairment was associated with an increased exposure to taspoglutide and an increased risk of GI AEs.
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Sturm S, Forsberg A, Nave S, Stenkrona P, Seneca N, Varrone A, Comley RA, Fazio P, Jamois C, Nakao R, Ejduk Z, Al-Tawil N, Akenine U, Halldin C, Andreasen N, Ricci B. Positron emission tomography measurement of brain MAO-B inhibition in patients with Alzheimer's disease and elderly controls after oral administration of sembragiline. Eur J Nucl Med Mol Imaging 2017; 44:382-391. [PMID: 27633250 PMCID: PMC5281649 DOI: 10.1007/s00259-016-3510-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 08/29/2016] [Indexed: 11/24/2022]
Abstract
PURPOSE In Alzheimer's disease (AD), increased metabolism of monoamines by monoamine oxidase type B (MAO-B) leads to the production of toxic reactive oxygen species (ROS), which are thought to contribute to disease pathogenesis. Inhibition of the MAO-B enzyme may restore brain levels of monoaminergic neurotransmitters, reduce the formation of toxic ROS and reduce neuroinflammation (reactive astrocytosis), potentially leading to neuroprotection. Sembragiline (also referred as RO4602522, RG1577 and EVT 302 in previous communications) is a potent, selective and reversible inhibitor of MAO-B developed as a potential treatment for AD. METHODS This study assessed the relationship between plasma concentration of sembragiline and brain MAO-B inhibition in patients with AD and in healthy elderly control (EC) subjects. Positron emission tomography (PET) scans using [11C]-L-deprenyl-D2 radiotracer were performed in ten patients with AD and six EC subjects, who received sembragiline each day for 6-15 days. RESULTS At steady state, the relationship between sembragiline plasma concentration and MAO-B inhibition resulted in an Emax of ∼80-90 % across brain regions of interest and in an EC50 of 1-2 ng/mL. Data in patients with AD and EC subjects showed that near-maximal inhibition of brain MAO-B was achieved with 1 mg sembragiline daily, regardless of the population, whereas lower doses resulted in lower and variable brain MAO-B inhibition. CONCLUSIONS This PET study confirmed that daily treatment of at least 1 mg sembragiline resulted in near-maximal inhibition of brain MAO-B enzyme in patients with AD.
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Affiliation(s)
- Stefan Sturm
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland.
- F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070, Basel, Switzerland.
| | - Anton Forsberg
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | - Stephane Nave
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland
| | - Per Stenkrona
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | | | - Andrea Varrone
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | | | - Patrik Fazio
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | - Candice Jamois
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland
| | - Ryuji Nakao
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | - Zbigniew Ejduk
- Internal Disease and Gastroenterology, Miedzyleski Specialistic Hospital, Warsaw, Poland
| | - Nabil Al-Tawil
- Karolinska Trial Alliance Phase 1 Unit, Karolinska University Hospital, Stockholm, Sweden
| | - Ulrika Akenine
- Karolinska Institutet Alzheimer Disease Research Centre and Clinical Trial Unit, Geriatric Clinic, Karolinska University Hospital, Huddinge, Sweden
| | - Christer Halldin
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | - Niels Andreasen
- Karolinska Institutet Alzheimer Disease Research Centre and Clinical Trial Unit, Geriatric Clinic, Karolinska University Hospital, Huddinge, Sweden
| | - Benedicte Ricci
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland
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Bäcker A, Göppert B, Sturm S, Abaffy P, Sollich T, Gruhl FJ. Impact of adjustable cryogel properties on the performance of prostate cancer cells in 3D. Springerplus 2016; 5:902. [PMID: 27386348 PMCID: PMC4923005 DOI: 10.1186/s40064-016-2629-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 06/20/2016] [Indexed: 11/12/2022]
Abstract
Background Biochemical and physical characteristics of extracellular environment play a key role in assisting cell behavior over different molecular pathways. In this study, we investigated how the presence of chemical binding sites, the pore network and the stiffness of designed scaffolds affected prostate cancer cells. Methods A blend of poly hydroxyethyl methacrylate–alginate–gelatin scaffold was synthesized by cryogelation process using polyethyleneglycol diacrylate (PEGda) and glutaraldehyde as cross linkers. The chemical and mechanical scaffold properties were varied by concentration of gelatin and PEGda, respectively. The pore network was modified by applying different ‘freezing time’. Growth, spheroid formation and localization of androgen receptor (AR) were measured to evaluate cell response within various cryogel types. Results Insufficient porosity in combination with a brittle nature affects cell growth negatively. Spheroid size was reduced by porosity, elasticity as well as by the absence of the cell adhesive motif composed of arginine, glycine und aspartic acid (RGD). Localization of AR indicates its activity and should be under normal culture conditions in the nucleus. But in this study, we could investigate for the first time that AR remains in the cytoplasm when AR positive prostate cancer cells are cultured in scaffolds without RGD as well as in case of an insufficient pore network (total porosity under 10 %) and a too less stiffness of around 10 kPa. Conclusions The results indicate that for getting a reliable preclinical drug screening a three-dimensional prostate model system with appropriate biochemical and physical surrounding is needed.
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Affiliation(s)
- A Bäcker
- Karlsruhe Institute of Technology (KIT), Institute of Microstructure Technology (IMT), 76344 Eggenstein-Leopoldshafen, Germany
| | - B Göppert
- Karlsruhe Institute of Technology (KIT), Institute of Microstructure Technology (IMT), 76344 Eggenstein-Leopoldshafen, Germany
| | - S Sturm
- Karlsruhe Institute of Technology (KIT), Institute of Microstructure Technology (IMT), 76344 Eggenstein-Leopoldshafen, Germany
| | - P Abaffy
- Karlsruhe Institute of Technology (KIT), Institute of Microstructure Technology (IMT), 76344 Eggenstein-Leopoldshafen, Germany
| | - T Sollich
- Karlsruhe Institute of Technology (KIT), Institute of Functional Interfaces (IFG), 76344 Eggenstein-Leopoldshafen, Germany
| | - F J Gruhl
- Karlsruhe Institute of Technology (KIT), Institute of Microstructure Technology (IMT), 76344 Eggenstein-Leopoldshafen, Germany
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Schöbl S, Sturm S, Janke W, Kroy K. Persistence-length renormalization of polymers in a crowded environment of hard disks. Phys Rev Lett 2014; 113:238302. [PMID: 25526167 DOI: 10.1103/physrevlett.113.238302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Indexed: 06/04/2023]
Abstract
The most conspicuous property of a semiflexible polymer is its persistence length, defined as the decay length of tangent correlations along its contour. Using an efficient stochastic growth algorithm to sample polymers embedded in a quenched hard-disk fluid, we find apparent wormlike chain statistics with a renormalized persistence length. We identify a universal form of the disorder renormalization that suggests itself as a quantitative measure of molecular crowding.
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Affiliation(s)
- S Schöbl
- Universität Leipzig, Institut für Theoretische Physik, Postfach 100 920, D-04009 Leipzig, Germany
| | - S Sturm
- Universität Leipzig, Institut für Theoretische Physik, Postfach 100 920, D-04009 Leipzig, Germany
| | - W Janke
- Universität Leipzig, Institut für Theoretische Physik, Postfach 100 920, D-04009 Leipzig, Germany
| | - K Kroy
- Universität Leipzig, Institut für Theoretische Physik, Postfach 100 920, D-04009 Leipzig, Germany
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Ricci B, Sturm S, Seneca N, Jamois C, Nave S, Ejduk Z, Skenkrona P, Varonne A, Forsberg A, Fazio P, Halldin C, Al‐Tawil N, Akenine U, Andreasen N. P3–300: Brain MAO‐B inhibition in healthy elderly and people with Alzheimer's disease after oral administration of RO4602522. Alzheimers Dement 2013. [DOI: 10.1016/j.jalz.2013.05.1374] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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24
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Högner C, Sturm S, Seger C, Stuppner H. Development and validation of a rapid ultra-high performance liquid chromatography diode array detector method for Vitex agnus-castus. J Chromatogr B Analyt Technol Biomed Life Sci 2013; 927:181-90. [PMID: 23522912 DOI: 10.1016/j.jchromb.2013.02.037] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2012] [Revised: 02/24/2013] [Accepted: 02/26/2013] [Indexed: 11/28/2022]
Abstract
A rapid ultra-high performance liquid chromatography diode array detector (UHPLC-DAD) method was developed and validated for the simultaneous determination of all classes of non-volatile phytochemicals (iridoids, flavonoids and diterpenes) in Vitex agnus-castus (Lamiaceae) fruits, a traditional medicinal plant used against premenstrual symptoms (PMS) and other disorders. Seven marker compounds, 3,4-dihydroxybenzoic acid, p-hydroxybenzoic acid, agnuside, 5-hydroxykaempferol-3,6,7,4'-tetramethylether, 1,2-dibenzoic acid glucose, methoxy-vitexilactone, and vitetrifolin D were isolated from the methanol extract of V. agnus-castus to be used as reference substances. Chromatographic separation was performed on a Zorbax Eclipse XDB-C18 (50mm×2.1mm) UHPLC column with 1.8μm particle size, within 20min. A solvent gradient from 0.5% acetic acid to acetonitrile at a flow rate of 0.6mL/min was used as mobile phase. Analyte detection and quantification was realized at 210nm and 260nm. The UHPLC-DAD assay was validated for the quantitative analysis of agnuside, isovitexin, casticin, 5-hydroxykaempferol-3,6,7,4'-tetramethylether and vitetrifolin D. It was found to be specific, accurate, precise, and reproducible for the quantification of these compound within a concentration range of 0.7-500.0μg/mL for casticin and 5-hydroxykaempferol-3,6,7,4'-tetramethylether, 1.4-1000.0μg/mL for isovitexin and agnuside, and 12.4-1000.0μg/mL for vitetrifolin D. Intra- and inter-day variations showed relative standard deviations (RSD) of less than 3.9% and 6.4%, respectively. Tentatively assignment of 62 chromatographic features found in the UHPLC-DAD assay was carried out by coupling the UHPLC instrument to a quadrupole time-of-flight mass spectrometer via an electrospray ionization interface (ESI-QTOF-MS) operated in positive and negative ion mode. By using the established quantitative UHPLC-DAD assay to asses agnuside, isovitexin, casticin, 5-hydroxykaempferol-3,6,7,4'-tetramethylether and vitetrifolin D in V. agnus-castus derived preparations as extracts, tinctures and tablets, the applicability of the developed assay to phytopharmaceuticals was successfully proven.
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Affiliation(s)
- C Högner
- Institute of Pharmacy/Pharmacognosy, CCB - Centrum of Chemistry and Biomedicine, University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
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Wagner A, Sturm S, Köhler F, Glazov DA, Volotka AV, Plunien G, Quint W, Werth G, Shabaev VM, Blaum K. g Factor of lithiumlike silicon 28Si11+. Phys Rev Lett 2013; 110:033003. [PMID: 23373920 DOI: 10.1103/physrevlett.110.033003] [Citation(s) in RCA: 3] [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: 10/10/2012] [Indexed: 06/01/2023]
Abstract
The g factor of lithiumlike silicon (28)Si(11+) has been measured in a triple-Penning trap with a relative uncertainty of 1.1×10(-9) to be g(exp)=2.000 889 889 9(21). The theoretical prediction for this value was calculated to be g(th)=2.000 889 909(51) improving the accuracy to 2.5×10(-8) due to the first rigorous evaluation of the two-photon exchange correction. The measured value is in excellent agreement with the theoretical prediction and yields the most stringent test of bound-state QED for the g factor of the 1s(2)2s state and the relativistic many-electron calculations in a magnetic field.
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Affiliation(s)
- A Wagner
- Max-Planck-Institut für Kernphysik, Heidelberg, Germany
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Sturm S, Wagner A, Schabinger B, Zatorski J, Harman Z, Quint W, Werth G, Keitel CH, Blaum K. g factor of hydrogenlike ²⁸Si¹³⁺. Phys Rev Lett 2011; 107:023002. [PMID: 21797600 DOI: 10.1103/physrevlett.107.023002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Indexed: 05/31/2023]
Abstract
We determined the experimental value of the g factor of the electron bound in hydrogenlike ²⁸Si¹³⁺ by using a single ion confined in a cylindrical Penning trap. From the ratio of the ion's cyclotron frequency and the induced spin flip frequency, we obtain g = 1.995 348 958 7(5)(3)(8). It is in excellent agreement with the state-of-the-art theoretical value of 1.995 348 958 0(17), which includes QED contributions up to the two-loop level of the order of (Zα)² and (Zα)⁴ and represents a stringent test of bound-state quantum electrodynamics calculations.
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Affiliation(s)
- S Sturm
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
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27
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Sturm S, Rožman KZ, Markoli B, Sarantopoulou E, Kollia Z, Cefalas AC, Kobe S. Formation of core-shell and hollow nanospheres through the nanoscale melt-solidification effect in the Sm-Fe(Ta)-N system. Nanotechnology 2010; 21:485603. [PMID: 21063053 DOI: 10.1088/0957-4484/21/48/485603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Sm-Fe-Ta-N-O nanospheres were synthesized by pulsed-laser deposition from a Sm(13.8)Fe(82.2)Ta(4.0) target in a nitrogen atmosphere. Three structurally and compositionally distinct types were identified: amorphous, core-shell and hollow nanospheres. Amorphous spheres were compositionally homogeneous and completely oxidized. The core-shell spheres were composed of an iron-rich crystalline core with up to 10 at.% interstitially incorporated nitrogen, surrounded by an amorphous and oxidized shell. The hollow spheres were characterized by voids filled with N(2) gas. It was found that the formation of either amorphous or complex nanospheres is defined by an initial Fe/Sm ratio within the molten droplet. The formation of hollow spheres is believed to be related to the general affinity of liquid metals for gas intake. During rapid solidification the dissolved gas in the melt is trapped within the surrounding solid rim, preventing the outwards diffusion of gas. As long as the amount of gas atoms in the melt is kept below its solubility limits it can be completely interstitially incorporated into the solid, thus forming crystalline Fe(N)-rich cores. If the melt contains more than an equilibrium amount of nitrogen it is possible that the gas recombines to form N(2) molecules, which are condensed inside the spheres.
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Affiliation(s)
- S Sturm
- Department for Nanostructured Materials, Jozef Stefan Institute, 1000 Ljubljana, Slovenia
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28
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Sturm S, Hammann F, Drewe J, Maurer HH, Scholer A. An automated screening method for drugs and toxic compounds in human serum and urine using liquid chromatography–tandem mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2010; 878:2726-32. [DOI: 10.1016/j.jchromb.2010.08.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2010] [Revised: 07/25/2010] [Accepted: 08/14/2010] [Indexed: 10/19/2022]
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Sturm S, Zhou S, Mai YW, Li Q. On stiffness of scaffolds for bone tissue engineering-a numerical study. J Biomech 2010; 43:1738-44. [PMID: 20227080 DOI: 10.1016/j.jbiomech.2010.02.020] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2008] [Revised: 02/15/2010] [Accepted: 02/15/2010] [Indexed: 11/19/2022]
Abstract
Tissue scaffolds are typically designed and fabricated to match native bone properties. However, it is unclear if this would lead to the best tissue ingrowth outcome within the scaffold as neo-tissue keeps changing the stiffness of entire construct. This paper presents a numerical method to address this issue for design optimization and assessment of tissue scaffolds. The elasticity tensors of two different types of bones are weighted by different multipliers before being used as the targets in scaffold design. A cost function regarding the difference between the effective elasticity tensor, calculated by the homogenization technique, and the target tensor, is minimized by using topology optimization procedure. It is found that different stiffnesses can lead to different remodeling results. The comparison confirms that bone remodeling is at its best when the scaffold elastic tensor matches or is slightly higher than the elastic properties of the host bone.
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Affiliation(s)
- Stefan Sturm
- Department of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
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Schabinger B, Sturm S, Blaum K, Quint W, Wagner A, Werth G. Creation of highly-charged calcium ions for theg-factor determination of the bound electron. ACTA ACUST UNITED AC 2009. [DOI: 10.1088/1742-6596/163/1/012108] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
Signal transducer and transcriptional activator (STAT) proteins are latent cytoplasmic transcription factors that are activated in response to stimulation by various cytokines. Protein Inhibitors of Activated STAT (PIAS) proteins comprise a family of five mammalian proteins which have been identified as potentially important downregulators of the STAT signaling pathway. We have previously reported the identification and expression of the mouse homologue of PIAS family member PIASgamma. Here we report the isolation by genomic 5'-RACE PCR and in vitro analysis of the mouse PIASgamma promoter region and the genomic structure and organization of the mouse and human PIASgamma genes. Human PIASgamma spans approximately 23 kb on chromosome 19 and is organized into ten exons. The size of mouse PIASgamma is 16 kb and also organized into ten exons with the intron/exon structure of the two genes conserved in both species. As a result, considerable conservatism of the mouse and human intron sequences was observed. Analysis of a 1.4 kb genomic fragment containing the mouse PIASgamma promoter allowed us to map the transcription 'Start' site of the gene, determine the sequences essential for the activity of this promoter and to define a minimal promoter region.
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Affiliation(s)
- S Sturm
- Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital/Harvard Medical School, Charlestown, MA, USA
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Knirsch U, Sturm S, Reuter A, Bachus R, Gosztonyi G, Voelkel H, Ludolph AC. Calcineurin A and calbindin immunoreactivity in the spinal cord of G93A superoxide dismutase transgenic mice. Brain Res 2001; 889:234-8. [PMID: 11166710 DOI: 10.1016/s0006-8993(00)03048-1] [Citation(s) in RCA: 16] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A qualitative immunohistochemical study was performed on calcineurin A- and calbindin-positive neurons in the spinal cord of transgenic mice, an animal model of amyotrophic lateral sclerosis, carrying the G93A mutation of the Cu/Zn-superoxide dismutase gene. The results show that calcineurin A-immunoreactive motoneurons are affected by the neurodegenerative process; in contrast, calbindin-positive cells are selectively spared. The findings suggest that calcineurin plays a role as an accessory factor responsible for selective vulnerability in the neurodegenerative process of amyotrophic lateral sclerosis.
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Affiliation(s)
- U Knirsch
- Department of Neurology, University of Ulm, Oberer Eselsberg 45, D-89081, Ulm, Germany.
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Zidorn C, Ellmerer-Müller EP, Ongania KH, Sturm S, Stuppner H. New taxonomically significant sesquiterpenoids from Leontodon autumnalis. J Nat Prod 2000; 63:812-816. [PMID: 10869207 DOI: 10.1021/np990554j] [Citation(s) in RCA: 14] [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] [Indexed: 05/23/2023]
Abstract
The methanolic extract of subaerial parts of Leontodon autumnalis afforded four new and two known sesquiterpenoids of the guaiane type. The known compounds were identified by means of (1)H and (13)C NMR spectroscopy as crepidiaside A (1) and B (2). The structures of the new compounds were determined by extensive 1D and 2D NMR experiments as 15-glucopyranosyloxy-2-oxo-guaia-3,11(13)-dien-1alp ha,5alpha, 6beta,7alpha,10alphaH-12,6-olide (3); 15-glucopyranosyloxy-2-oxo-guai-3-en-1alpha,5alpha+ ++,6beta,7alpha, 10alpha,11betaH-12,6-olide (4); 15-hydroxy-2-oxo-guai-3-en-1alpha, 5alpha,6beta,7alpha,10alpha,11betaH-12,6-+ ++olide (5); and 15-glucopyranosyloxy-2-oxo-guaia-3,11(13)-dien-1bet a,5alpha,6beta, 7alpha,10alphaH-12,6-olide (6), respectively. HPLC-DAD and HPLC-MS analyses of crude extracts of subaerial parts of 25 different taxa of the genus Leontodon revealed that compounds 1 and 2 occur in all investigated members of the section Oporinia (L. autumnalis, L. croceus, L. helveticus, L. montaniformis, L. montanus, L. pyrenaicus, and L. rilaensis) and in L. duboisii from the section Kalbfussia. Compounds 1-6 are detectable neither in other investigated taxa of Kalbfussia (L. cichoraceus, L. muelleri, and L. palisae) nor in any members of the subgenus Leontodon. Compounds 3-5 occur in high amounts only in L. croceus and L. pyrenaicus and in samples of L. autumnalis from northwestern Europe. In other members of the section Oporinia, in L. duboisii as well as in samples of L. autumnalis from the Pyrenees, the Alps, the Carpathians, and southern Central Europe, these substances occur only in trace amounts; in L. montanus and its closest relatives, compounds 3-5 are not detectable at all. Compound 6 is only detectable in samples of L. autumnalis, L. helveticus, L. pyrenaicus, L. rilaensis, and L. duboisii.
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Affiliation(s)
- C Zidorn
- Institut für Pharmazie der Universität Innsbruck, Josef-Möller-Haus, Innrain 52, A-6020 Innsbruck, Austria.
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Abstract
Signal transducer and activator of transcription (STAT) proteins are latent cytoplasmic transcription factors that become activated in response to stimulation by various cytokines. Recently a new family of five structurally related proteins, called PIAS (Protein Inhibitor of Activated STAT) has been identified as potentially important downregulators of this pathway. Members of the PIAS family of STAT inhibitors may play a prominent role in the downregulation of STAT-mediated signaling processes. In this article we describe the isolation of the cDNA and expression of the gene for the murine homologue of the human STAT inhibitor family member PIASgamma. The cDNA for mPIASgamma encodes a protein of 507 amino acids that is highly homologous to the human protein and is expressed in the mouse as early as d 7.5 of gestation. In situ hybridizations of staged mouse embryos localized the transcript for the PIASgamma gene to the limbs, neuroepithelium, and the inner root sheath of the hair follicle, suggesting a role in the development of these structures. Immunostaining studies with a polyclonal antibody (PAb) recognizing human PIASgamma localized the protein in the hair follicle of human scalp hair and in monkey neuronal cells. Thus PIASgamma exhibits a highly selective pattern of expression, suggesting that it modulates the response of cells to developmental cues.
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Affiliation(s)
- S Sturm
- Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital/Harvard Medical School, Charlestown 02129, USA
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Sturm S. [Is practice better than study? Report from the course "Nursing Science" in Darmstadt]. Kinderkrankenschwester 1998; 17:528-9. [PMID: 10426038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
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Abstract
The technique of capillary electrophoresis - mass spectrometry (CE-MS) was applied for determination of isoquinoline alkaloids in crude methanolic extracts of medicinal plants. For the CE separations ammonium formate buffer solutions (70 or 100 mM, pH 3.0 or 4.0) containing 10% methanol or 20-60% acetonitrile as additives were used. The applied voltage was 25 kV, the thermostating temperature was kept constant at 25 degrees C. Coupling with the mass spectrometer was performed via an atmospherical pressure ionization (API) interface and the electrospray ionization technique (ESI). As sheath liquid 5 mM formic acid in acetonitrile at a flow rate of 3 microL/min was used. The spray voltage was 4.5 kV and the temperature of the heated capillary was chosen to be 200 degrees C. Detection in the positive ionization mode resulted in mass spectra showing either the molecular ions [M]+ or the protonated molecular ions [M+H]+. The presented method allows detection and identification of isoquinoline alkaloids in crude methanolic extracts of medicinal plants as Eschscholzia californica CHAM. (Papaveraceae), Hydrastis canadensis L. (Ranunculaceae), Berberis vulgaris L. (Berberidaceae), Jateorhiza palmata (LAM.) MIERS (Menispermaceae) and Chelidonium majus L. (Papaveraceae).
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Affiliation(s)
- S Sturm
- Institute of Pharmacognosy, University of Innsbruck, Austria.
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Abstract
In Schizosaccharomyces pombe the "start" of the cell cycle is regulated by two parallel, functionally overlapping complexes composed of Res1-Cdc10 and Res2-Cdc10. Res1 and Res2 are structurally very homologous and are required for the start of the mitotic and meiotic cycle, respectively. We have addressed the question which parts of the proteins are essential for function and determine the functional specificity. Several discrete domains in the nonconserved C-terminal region are essential for the mitotic and meiotic start function and determine the functional specificity independently of the structurally conserved motifs at the N-terminal end and in the center. One of these domains in Res2 restricts Res2 to interact only with Rep2. Res2 without this domain behaves like a functional chimera having the properties of Res2 and Res1. Likewise, internally truncated forms of Res1 lacking the centrally located ankyrin repeats and adjacent sequences can partially suppress the meiotic defect in res2- cells. These truncated Res1 molecules behave like functional chimeras with the properties of Res1 and Res2.
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Affiliation(s)
- S Sturm
- Okayama Cell Switching Project, Research Development Corporation of Japan, Kyoto, Japan
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Sturm S, Gil RR, Chai HB, Ngassapa OD, Santisuk T, Reutrakul V, Howe A, Moss M, Besterman JM, Yang SL, Farthing JE, Tait RM, Lewis JA, O'Neill MJ, Farnsworth NR, Cordell GA, Pezzuto JM, Kinghorn AD. Lupane derivatives from Lophopetalum wallichii with farnesyl protein transferase inhibitory activity. J Nat Prod 1996; 59:658-663. [PMID: 8759161 DOI: 10.1021/np960370u] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Chloroform-soluble extracts of the stems and of the mixed stems and stem bark of Lophopetalum wallichii were found to be inhibitory in a farnesyl protein transferase (FPTase) bioassay system. During the course of activity-guided fractionation, the known lupane-type triterpenes, ochraceolide A (1), ochraceolide B (2), betulin, and lupeol and the new lupane lactone, dihydro ochraceolide A (4), were isolated. The stereochemistry of the epoxide group of ochraceolide B (2) was determined by preparation of both epoxide isomers [2, and the new semisynthetic derivative, 20-epi-ochraceolide B (3)] from 1. The structure of 4 was established by reduction of 1 with sodium borohydride. Compounds 1 and 2 exhibited significant inhibitory activity in the FPTase assay (IC50 values of 1.0 and 0.7 microgram/mL, respectively). Lupeol was found to be weakly active (IC50 65.0 micrograms/mL) in this test system, whereas no significant inhibition was detected for betulin or compounds 3 or 4. When evaluated against a panel of human cancer cells in culture, compounds 1 and 4 were modestly cytotoxic. Compounds 2 and 3 were not active in the panel.
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Affiliation(s)
- S Sturm
- Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago 60612, USA
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Nakashima N, Tanaka K, Sturm S, Okayama H. Fission yeast Rep2 is a putative transcriptional activator subunit for the cell cycle ‘start’ function of Res2-Cdc10. EMBO J 1995; 14:4794-802. [PMID: 7588609 PMCID: PMC394577 DOI: 10.1002/j.1460-2075.1995.tb00161.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In the yeast cell cycle 'start' requires sets of the Cdc10/ SWI family of transcriptional factors which activate the MCB cis elements contained in genes essential for S phase progression. Fission yeast possess two such overlapping systems, Res1-Cdc10 and Res2-Cdc10, both of which act to start the mitotic and meiotic cycles. We have recently isolated rep2+ as a multicopy suppressor of a temperature-sensitive cdc10 mutant which encodes a zinc finger protein. Here we show that the Rep2 zinc finger protein is an essential component of the active Res2-Cdc10 transcriptional regulator complex and likely to play a role in the control of cell cycle 'start'. Our data suggest that Rep2 is a transcriptional activator subunit which interacts with the MCB binding subunit complex formed by Res2 and Cdc10.
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Affiliation(s)
- N Nakashima
- Department of Biochemistry, University of Tokyo, Faculty of Medicine, Japan
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Stuppner H, Sturm S, Mulinacci N, Vincieri F. Capillary zone electrophoretic analysis of the main alkaloids fromEschscholtzia californica. Chromatographia 1993. [DOI: 10.1007/bf02274105] [Citation(s) in RCA: 8] [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: 10/25/2022]
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Sturm S. [The pediatric nurse--an angel on earth?]. Kinderkrankenschwester 1993; 12:323. [PMID: 8398800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Fält IC, Schweda EK, Weintraub A, Sturm S, Timmis KN, Lindberg AA. Expression of the Shigella dysenteriae type-1 lipopolysaccharide repeating unit in Escherichia coli K12/Shigella dysenteriae type-1 hybrids. Eur J Biochem 1993; 213:573-81. [PMID: 7682945 DOI: 10.1111/j.1432-1033.1993.tb17796.x] [Citation(s) in RCA: 19] [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] [Indexed: 01/26/2023]
Abstract
The structures of the polysaccharide part of lipopolysaccharides isolated from eight Escherichia coli K12/Shigella dysenteriae type 1 hybrids have been determined using sugar and methylation analysis plus 1H- and 13C-nuclear magnetic resonance spectroscopy. The hybrids express parts of the S. dysenteriae type 1 O-antigen tetrasaccharide repeating unit because of the presence of pSS3, a plasmid expressing an alpha-galactosyl: lipopolysaccharide transferase and pSS9, a pBR322 plasmid expressing S. dysenteriae type 1 rfb genes. The various classes of hybrids are the result of transposon Tn 1000 insertions in pSS9 inactivating different rfb genes. The following structural elements were found. E. coli K12 (pSS3) and E. coli K12 (pSS3, pSS9-6; a class I hybrid); alpha-D-Galp(1-->3)beta-D-GlcpNAc(1-->. Class IV hybrids: E. coli K12 (pSS3, pSS9-36); (pSS3, pSS9-107) and (pSS3, pSS9-114); alpha-L-Rhap(1-->2)alpha-D-Galp(1-->3)beta-D-GlcpNAc(1-->. Class V hybrids: E. coli K12 (pSS3, pSS9-78) and (pSS3, pSS9-111); alpha-L-Rhap(1-->3)alpha-L-Rhap(1-->2)alpha-D-Galp(1-->3)bet a-D-GlcpNAc(1-->. The structural sequences are identical to those found in the lipopolysaccharide from native S. dysenteriae type 1. In the hybrid strains, the terminal non-reducing GlcNAc residue of the E. coli K12 core is fully substituted by S. dysenteriae type 1 repeating units, or parts thereof.
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Affiliation(s)
- I C Fält
- Karolinska Institute, Department of Clinical Bacteriology, Huddinge Hospital, Sweden
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Abstract
Four classes of murine leukemia virus (MuLV) which display distinct cellular tropisms and bind to different retrovirus receptors to initiate virus infection have been described. In the present study, we describe a rapid, sensitive immunofluorescence assay useful for characterizing the initial binding of MuLV to cells. By using the rat monoclonal antibody 83A25 (L. H. Evans, R. P. Morrison, F. G. Malik, J. Portis, and W. J. Britt, J. Virol. 64:6176-6183, 1990), which recognizes an epitope of the envelope gp70 molecule common to the different classes of MuLV, it is possible to analyse the binding of ecotropic, amphotropic, or xenotropic MuLV by using only a single combination of primary and secondary antibodies. The MuLV binding detected by this assay is envelope receptor specific and matches the susceptibility to infection determined for cells from a variety of species. The binding of amphotropic MuLV to NIH 3T3 cells was shown to be rapid, saturable, and temperature dependent. Chinese hamster ovary (CHO-K1) cells normally lack the ability to bind ecotropic virus and are not infectible by ecotropic vectors. Expression of the cloned ecotropic retrovirus receptor gene (Rec) in CHO-K1 cells confers high levels of ecotropic virus-specific binding and confers susceptibility to infection. Characterization of MuLV binding to primary cells may provide insight into the infectibility of cells by retroviruses and aid in the selection of appropriate vectors for gene transfer experiments.
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Affiliation(s)
- M J Kadan
- Gene Transfer Laboratory, Genetic Therapy, Inc., Gaithersburg, Maryland 20878
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Cornetta K, Morgan RA, Gillio A, Sturm S, Baltrucki L, O'Reilly R, Anderson WF. No retroviremia or pathology in long-term follow-up of monkeys exposed to a murine amphotropic retrovirus. Hum Gene Ther 1991; 2:215-9. [PMID: 1661171 DOI: 10.1089/hum.1991.2.3-215] [Citation(s) in RCA: 64] [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: 12/28/2022] Open
Abstract
Four monkeys were exposed to a retroviral vector and replication-competent murine amphotropic retrovirus in a bone marrow transplantation/gene transfer protocol (Kantoff et al., 1987). We have studied these animals 2 and 3 years post-transplantation and did not detect replicating virus in serum, peripheral blood mononuclear cells, or bone marrow cells. Amphotropic envelope sequences could not be detected in blood or bone marrow cells by Southern blotting or the polymerase chain reaction. Antibodies directed against the p30 and gp70 viral antigens were detected by Western blot and immunoprecipitation. The animals remain alive and well. Our findings suggest that primates can clear murine amphotropic retroviruses even when exposure occurs during a time of severe immunosuppression.
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MESH Headings
- Adenosine Deaminase/genetics
- Animals
- Antibodies, Viral/blood
- Base Sequence
- Blood/microbiology
- Blotting, Southern
- Blotting, Western
- Bone Marrow/microbiology
- Bone Marrow Transplantation
- DNA, Viral/analysis
- Genes, env
- Genetic Engineering
- Genetic Vectors
- Immunocompromised Host
- Leukemia Virus, Murine/genetics
- Leukemia Virus, Murine/immunology
- Leukemia Virus, Murine/isolation & purification
- Leukemia Virus, Murine/physiology
- Leukocytes, Mononuclear/microbiology
- Macaca fascicularis/blood
- Macaca fascicularis/immunology
- Macaca fascicularis/microbiology
- Molecular Sequence Data
- Polymerase Chain Reaction
- Recombinant Proteins/genetics
- Retrospective Studies
- Retroviridae/genetics
- Viremia
- Virus Replication
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Affiliation(s)
- K Cornetta
- Molecular Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892
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Cornetta K, Moen RC, Culver K, Morgan RA, McLachlin JR, Sturm S, Selegue J, London W, Blaese RM, Anderson WF. Amphotropic murine leukemia retrovirus is not an acute pathogen for primates. Hum Gene Ther 1990; 1:15-30. [PMID: 1964393 DOI: 10.1089/hum.1990.1.1-15] [Citation(s) in RCA: 127] [Impact Index Per Article: 3.7] [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: 12/29/2022] Open
Abstract
The in vivo fate of amphotropic murine leukemia retrovirus was studied in five rhesus monkeys. Retrovirus infused intravenously into 3 normal animals and 1 immunosuppressed animal was cleared rapidly from the circulation and subsequent viremia has not been detected (mean follow-up of 27.4 months). A fifth monkey was immunosuppressed and transplanted with virus-producing autologous fibroblasts in addition to an intraperitoneal injection of virus. This animal was viremic for 2 days and its lymph node cells and peripheral blood mononuclear cells were shown to be producing virus for up to 22 days post-inoculation, but subsequently has been negative after 17.0 months of analysis. In the 5 animals studied (combined mean follow-up of 25.7 months), clinical illness has not been identified at any time. Therefore, murine amphotropic retroviruses do not appear to pose an acute health risk.
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Affiliation(s)
- K Cornetta
- Laboratory of Molecular Hematology, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892
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Sturm S, Timmis KN. Cloning of the rfb gene region of Shigella dysenteriae 1 and construction of an rfb-rfp gene cassette for the development of lipopolysaccharide-based live anti-dysentery vaccines. Microb Pathog 1986; 1:289-97. [PMID: 2469931 DOI: 10.1016/0882-4010(86)90054-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Recent studies have shown that determinants for the production of O antigen lipopolysaccharide in Shigella dysenteriae 1 are distributed over two distinct genetic elements, the chromosome and a 9 kb plasmid designated pHW400. In this communication, we describe the cloning of all determinants necessary for S. dysenteriae 1 O antigen production in E. coli K-12 and their combination in a single plasmid. An RP4::miniMu R-prime plasmid, R-prime 40, containing the his-rfb (histidine biosynthesis-lipopolysaccharide biosynthesis) gene region of the Shigella dysenteriae 1 chromosome was generated. E. coli K-12 bacteria containing R-prime 40 and pSS8, a transposon Tn5-tagged derivative of pHW400, produced lipopolysaccharide indistinguishable from that of S. dysenteriae 1. Small DNA fragments containing the rfb gene cluster and the rfp gene were subcloned from R-prime 40 and pSS8 and subsequently combined in vector pACYC184 to produce pSS37. This latter plasmid when introduced by transformation into E. coli K-12 provoked the formation of S. dysenteriae 1 O-specific lipopolysaccharide, a feature that suggests it may be useful in the construction of LPS-based live vaccines against the Shiga bacillus.
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Affiliation(s)
- S Sturm
- Department of Medical Biochemistry, University Medical Centre, University of Geneva, Switzerland
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Sturm S, Jann B, Jann K, Fortnagel P, Timmis KN. Genetic and biochemical analysis of Shigella dysenteriae 1 O antigen polysaccharide biosynthesis in Escherichia coli K-12: 9 kb plasmid of S. dysenteriae 1 determines addition of a galactose residue to the lipopolysaccharide core. Microb Pathog 1986; 1:299-306. [PMID: 2469932 DOI: 10.1016/0882-4010(86)90055-0] [Citation(s) in RCA: 17] [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: 01/01/2023]
Abstract
Production of the somatic antigen, O-specific polysaccharide of Shigella dysenteriae 1 is determined by the chromosomal rfb gene cluster and the rfp gene located on the 9 kb plasmid pHW400 carried by this organism. When transferred to Escherichia coli K-12, which produces lipopolysaccharide consisting only of core oligosaccharide linked to lipid A, rfp gene-containing plasmids caused modification of the core oligosaccharide leading to the appearance of core molecules with new electrophoretic mobilities. Chemical analysis of the modified core has shown that it is substituted with a galactose residue which is the first sugar of the O-polysaccharide repeat unit.
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Affiliation(s)
- S Sturm
- Department of Medical Biochemistry, University of Geneva, Switzerland
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Sturm S, Jann B, Jann K, Fortnagel P, Timmis KN. Genetic and biochemical analysis of Shigella dysenteriae 1 O antigen polysaccharide biosynthesis in Escherichia coli K-12: structure and functions of the rfb gene cluster. Microb Pathog 1986; 1:307-24. [PMID: 2469933 DOI: 10.1016/0882-4010(86)90056-2] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.4] [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: 01/01/2023]
Abstract
The genetic organization and functions of the Shigella dysenteriae 1 rfb gene cluster, which specifies the somatic O antigen in this organism, have been studied in Escherichia coli K-12 by insertion and deletion mutagenesis of pSS9, a pBR322 hybrid containing the Shigella rfb genes. On the basis of the sensitivity/resistance to rough-specific bacteriophage T3 of E. coli K-12 derivatives containing mutant pSS9 plasmids, of the banding patterns and immunoreactivity of LPS isolated from such derivatives and electrophoresed on SDS-polyacrylamide gels, and of the sugar composition of the polysaccharide portion of the LPS determined by chemical analysis, six determinants for O antigen production were identified and localized. At least two determinants are involved in synthesis of TDP-rhamnose and the transfer of a rhamnose residue to the galactose-substituted core. One of these functions is probably TDP-rhamnose synthetase. A third function effects the transfer of a second rhamnose residue to the rha----gal-substituted core. A fourth function, for which evidence was obtained for two determinants (cistrons), is N-acetylglucosamine transferase, whereas a sixth determinant is necessary for extension of the first completed side chain repeat unit to the full O antigen polymer. These results confirmed the previously-determined chemical composition of the S. dysenteriae 1 O antigen and demonstrated that the order of the sugars is glcNAc----rha----rha----gal with gal as the first sugar linked to the core. Evidence was obtained for at least two transcriptional units in the rfb gene cluster and the approximate locations of two promoters are suggested. The detection of new electrophoretic species of LPS that may correspond to LPS biosynthetic intermediates, and the finding on the cell surfaces of structures corresponding to LPS core substituted with one or more O-specific sugars, appear to be novel findings.
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Affiliation(s)
- S Sturm
- Department of Medical Biochemistry, University of Geneva, Switzerland
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Sturm S, Fortnagel P, Timmis KN. Immunoblotting procedure for the analysis of electrophoretically-fractionated bacterial lipopolysaccharide. Arch Microbiol 1984; 140:198-201. [PMID: 6084988 DOI: 10.1007/bf00454926] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A procedure is described for the efficient transfer of fractionated bacterial lipopolysaccharide (LPS) from SDS-polyacrylamide gels to nitrocellulose filters, and its subsequent display by a peroxidase-linked antibody. The method is sensitive, and reveals and resolves high molecular weight LPS molecules having side chain lengths of up to and greater than 30 repeat units. It is useful for the rapid analysis of LPS in bacterial outer membrane preparations.
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