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Jannink T, Bordewijk EM, Aalberts J, Hendriks J, Lehmann V, Hoek A, Goddijn M, van Wely M. Anxiety, depression, and body image among infertile women with and without polycystic ovary syndrome. Hum Reprod 2024; 39:784-791. [PMID: 38335234 PMCID: PMC10988102 DOI: 10.1093/humrep/deae016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 12/27/2023] [Indexed: 02/12/2024] Open
Abstract
STUDY QUESTION In women undergoing fertility treatment, do those with polycystic ovary syndrome (PCOS) have a higher prevalence of symptoms of anxiety and depression and lower body appreciation than women without PCOS? SUMMARY ANSWER Having PCOS was not associated with symptoms of anxiety and depression but was associated with somewhat lower body appreciation. WHAT IS KNOWN ALREADY PCOS has been associated with a higher chance to develop mental health problems, like anxiety, and body image concerns. The International Guidelines on PCOS recommend that all women with PCOS should routinely be screened for anxiety and depressive disorders. In most studies in this field, the comparison group included healthy women without fertility problems. STUDY DESIGN, SIZE, DURATION We conducted a cross-sectional survey study between May 2021 and July 2023, using an online questionnaire. We informed women about this study at fertility clinics in the Netherlands through posters and leaflets and on the websites of the Dutch patient organizations Freya and Stichting PCOS. PARTICIPANTS/MATERIALS, SETTING, METHODS This study included women with infertility, with and without PCOS, who were undergoing fertility treatment. Women completed two assessment tools: the Hospital Anxiety and Depression Scale (HADS) and the Body Appreciation Scale-2 (BAS-2). Primary outcomes were clinically relevant symptoms of anxiety (score ≥ 11) and depression (score ≥ 11), and BAS-2 scores. Secondary outcomes were mean anxiety and depression scores and anxiety and depression scores of 8 and higher. Dichotomous outcomes and continuous outcomes were analysed using logistic and linear regression analyses adjusted for age, BMI, and duration of infertility. MAIN RESULTS AND THE ROLE OF CHANCE A total of 1025 women currently undergoing infertility treatment participated, of whom 502 (49.0%) had PCOS and 523 (51.0%) had other infertility diagnoses. We found self-reported clinically relevant symptoms of anxiety in 33.1% of women with PCOS and in 31.0% of women with other infertility diagnoses (adjusted OR: 0.99, 95% CI 0.74-1.31). Clinically relevant symptoms of depression were reported in 15.5% of women with PCOS versus 14.5% of women with other infertility diagnoses (adjusted OR: 1.04, 95% CI 0.71-1.50). Women with PCOS reported slightly less body appreciation (adjusted mean difference: -1.34, 95% CI -2.32 to -0.36). LIMITATIONS, REASONS FOR CAUTION Results are based on self-report and may have been affected by sampling bias. WIDER IMPLICATIONS OF THE FINDINGS Although guidelines recommend screening women with PCOS, feelings of anxiety and depression can be present in any woman undergoing fertility treatments. We advise fertility clinics to be aware of women's mental health issues and to offer support accordingly, as a part of routine care. STUDY FUNDING/COMPETING INTEREST(S) This study did not receive specific funding. All authors report no conflict of interest related to the current research. TRIAL REGISTRATION NUMBER This study was pre-registered at OSF: https://osf.io/qbeav.
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Affiliation(s)
- T Jannink
- Department of Obstetrics and Gynaecology, Centre for Reproductive Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
- Amsterdam Reproduction and Development Institute, Amsterdam UMC, Amsterdam, The Netherlands
| | - E M Bordewijk
- Department of Obstetrics and Gynaecology, Centre for Reproductive Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
- Amsterdam Reproduction and Development Institute, Amsterdam UMC, Amsterdam, The Netherlands
| | - J Aalberts
- Department of Obstetrics and Gynaecology, Centre for Reproductive Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - J Hendriks
- Department of Obstetrics and Gynaecology, Centre for Reproductive Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - V Lehmann
- Amsterdam Reproduction and Development Institute, Amsterdam UMC, Amsterdam, The Netherlands
- Department of Medical Psychology Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - A Hoek
- Department of Obstetrics and Gynaecology, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - M Goddijn
- Department of Obstetrics and Gynaecology, Centre for Reproductive Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
- Amsterdam Reproduction and Development Institute, Amsterdam UMC, Amsterdam, The Netherlands
| | - M van Wely
- Department of Obstetrics and Gynaecology, Centre for Reproductive Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
- Amsterdam Reproduction and Development Institute, Amsterdam UMC, Amsterdam, The Netherlands
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van der Meer DJ, Karim-Kos HE, Elzevier HW, Dinkelman-Smit M, Kerst JM, Atema V, Lehmann V, Husson O, van der Graaf WTA. The increasing burden of testicular seminomas and non-seminomas in adolescents and young adults (AYAs): incidence, treatment, disease-specific survival and mortality trends in the Netherlands between 1989 and 2019. ESMO Open 2024; 9:102231. [PMID: 38244349 PMCID: PMC10937200 DOI: 10.1016/j.esmoop.2023.102231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 11/11/2023] [Accepted: 12/21/2023] [Indexed: 01/22/2024] Open
Abstract
BACKGROUND Testicular cancer incidence among adolescents and young adults (AYAs, aged 18-39 years at diagnosis) is increasing worldwide and most patients will survive the initial disease. Still, detailed epidemiological information about testicular cancer among AYAs is scarce. This study aimed to provide a detailed overview of testicular cancer trends in incidence, treatment, long-term relative survival and mortality by histological subtype among AYAs diagnosed in the Netherlands between 1989 and 2019. MATERIALS AND METHODS Data of all malignant testicular cancers (ICD-code C62) were extracted from the Netherlands Cancer Registry. Mortality data were retrieved from Statistics Netherlands. European age-standardized incidence and mortality rates with average annual percentage change statistics and relative survival estimates up to 20 years of follow-up were calculated. RESULTS A total of 12 528 testicular cancers were diagnosed between 1989 and 2019. Comparing 1989-1999 to 2010-2019, the incidence increased from 4.4 to 11.4 for seminomas and from 5.7 to 11.1 per 100 000 person-years for non-seminomas. Rising trends were most prominent for localized disease. Radiotherapy use in localized testicular seminomas declined from 78% in 1989-1993 to 5% in 2015-2019. Meanwhile, there was a slight increase in chemotherapy use. Most AYAs with localized seminomas and non-seminomas received active surveillance only (>80%). Overall, relative survival estimates remained well above 90% even at 20 years of follow-up for both seminomas and non-seminomas. Mortality rates declined from 0.5 to 0.4 per 100 000 person-years between 1989-1999 and 2010-2019. CONCLUSIONS The incidence of seminoma and non-seminoma testicular cancers significantly increased in AYAs in the Netherlands between 1989 and 2019. There was a shift towards less-aggressive treatment regimens without negative survival effects. Relative survival estimates remained well above 90% at 20 years of follow-up in most cases. Testicular cancer mortality was already low, but has improved further over time, which makes survivorship care an important issue for these young adults.
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Affiliation(s)
- D J van der Meer
- Department of Medical Oncology, Netherlands Cancer Institute-Antoni van Leeuwenhoek, Amsterdam; Department of Psychosocial Research and Epidemiology, Netherlands Cancer Institute, Amsterdam; Department of Medical Oncology, Erasmus MC Cancer Institute, Erasmus University Medical Center, Rotterdam.
| | - H E Karim-Kos
- Princess Máxima Center for Pediatric Oncology, Utrecht; Department of Research and Development, Netherlands Comprehensive Cancer Organization (IKNL), Utrecht
| | - H W Elzevier
- Department of Urology and Medical Decision Making, Leiden University Medical Centre, Leiden
| | - M Dinkelman-Smit
- Department of Urology, Erasmus MC Cancer Institute, Erasmus University Medical Center, Rotterdam
| | - J M Kerst
- Department of Medical Oncology, Netherlands Cancer Institute-Antoni van Leeuwenhoek, Amsterdam
| | - V Atema
- Department of Research and Development, Netherlands Comprehensive Cancer Organization (IKNL), Utrecht
| | - V Lehmann
- Department of Medical Psychology, Cancer Center Amsterdam, Amsterdam University Medical Center, Amsterdam; Cancer Center Amsterdam (CCA), Amsterdam
| | - O Husson
- Department of Medical Oncology, Netherlands Cancer Institute-Antoni van Leeuwenhoek, Amsterdam; Department of Psychosocial Research and Epidemiology, Netherlands Cancer Institute, Amsterdam; Department of Surgical Oncology, Erasmus MC Cancer Institute, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - W T A van der Graaf
- Department of Medical Oncology, Netherlands Cancer Institute-Antoni van Leeuwenhoek, Amsterdam; Department of Medical Oncology, Erasmus MC Cancer Institute, Erasmus University Medical Center, Rotterdam
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van den Hoek Bos- DW, Tuinman MA, Hillen MA, Huijgens FL, Kurpershoek E, Calaminus G, Kaatsch P, Hagedoorn M, Lehmann V. DISCLOSING A HISTORY OF CHILDHOOD CANCER TO ROMANTIC PARTNERS. Psychooncology 2023. [PMID: 36998113 DOI: 10.1002/pon.6130] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 03/21/2023] [Accepted: 03/22/2023] [Indexed: 04/01/2023]
Abstract
OBJECTIVE To describe young adult childhood cancer survivors' disclosure of their cancer history (i.e., disclosure behavior, difficulty, and timing), perceived partner responses, and associations with relationship status satisfaction. METHODS German long-term survivors of childhood cancer (N=509; response rate: 31.3%, age 21-26, 59.7% female) completed a registry-based nationwide survey (embedded mixed methods design, including closed and open-ended questions) on measures about disclosure history (behavior, difficulty, and timing), partner responses, and relationship status satisfaction. Statistical (χ2 -, t-, or F-tests) and qualitative analyses were conducted. RESULTS Half of all survivors always disclosed their cancer history to romantic partners. Thereby, three themes for considering (non-)disclosure were identified: Survivors' attitudes, having integrated cancer as part of their identity, and anticipated effects on romantic relationships. About 40% indicated having no difficulties with disclosing their cancer history. The timing of disclosure varied, with most survivors disclosing after a few dates. Facilitators of disclosure were the visibility of their former illness (e.g., scars), having trust in a (potential) partner, getting older/mature, and previous positive experiences with disclosure. Few survivors (13.8%) had ever experienced negative responses from dating partners. Yet, those who had negative experiences, found it more difficult to disclose their cancer history. Survivors were overall rather satisfied with their relationship status, with partnered survivors reporting greater satisfaction than singles (Hedge's g=1.68); and particularly partnered survivors with past positive responses being most satisfied. CONCLUSIONS Young adult childhood cancer survivors appear rather open in disclosing their cancer history to (potential) romantic partners, and few experienced negative responses. Psycho-educational programs may emphasize such findings in helping to prevent fear of disclosure or avoidance of dating and disclosure among survivors. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- D W van den Hoek Bos-
- Amsterdam UMC location University of Amsterdam, department of Medical Psychology, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Public Health research institute, Quality of Care program, Amsterdam, The Netherlands
- Cancer Center Amsterdam, Cancer Treatment and Quality of Life, Amsterdam, The Netherlands
| | - M A Tuinman
- Department of Health Psychology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - M A Hillen
- Amsterdam UMC location University of Amsterdam, department of Medical Psychology, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Public Health research institute, Quality of Care program, Amsterdam, The Netherlands
- Cancer Center Amsterdam, Cancer Treatment and Quality of Life, Amsterdam, The Netherlands
| | - F L Huijgens
- Amsterdam UMC location University of Amsterdam, department of Medical Psychology, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Public Health research institute, Quality of Care program, Amsterdam, The Netherlands
- Cancer Center Amsterdam, Cancer Treatment and Quality of Life, Amsterdam, The Netherlands
| | - E Kurpershoek
- Amsterdam UMC location University of Amsterdam, department of Medical Psychology, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Public Health research institute, Quality of Care program, Amsterdam, The Netherlands
| | - G Calaminus
- Department of Pediatric Hematology and Oncology, University Hospital Bonn, Bonn, Germany
| | - P Kaatsch
- Institute of Medical Biostatistics, University Medical Center Mainz, German Childhood Cancer Registry (GCCR), Epidemiology and Informatics (IMBEI), Mainz, Germany
| | - M Hagedoorn
- Department of Health Psychology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - V Lehmann
- Amsterdam UMC location University of Amsterdam, department of Medical Psychology, Meibergdreef 9, Amsterdam, The Netherlands
- Cancer Center Amsterdam, Cancer Treatment and Quality of Life, Amsterdam, The Netherlands
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van der Velden NCA, van der Kleij MBA, Lehmann V, Smets EMA, Stouthard JML, Henselmans I, Hillen MA. Communication about Prognosis during Patient-Initiated Second Opinion Consultations in Advanced Cancer Care: An Observational Qualitative Analysis. Int J Environ Res Public Health 2021; 18:ijerph18115694. [PMID: 34073341 PMCID: PMC8199300 DOI: 10.3390/ijerph18115694] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 05/19/2021] [Accepted: 05/21/2021] [Indexed: 11/16/2022]
Abstract
Prognostic communication is essential for patients with advanced cancer to enable informed medical decision-making and end-of-life planning. Discussing prognosis is challenging, and might be especially complex for oncologists conducting a second opinion (SO). Survival data are often lacking, and consulting oncologists need to consider previously conveyed information and patients’ relationship with the referring oncologist. We qualitatively investigated how advanced cancer patients and consulting oncologists discuss prognosis during audio-recorded SO consultations (N = 60), including prognostic information received from the referring oncologist. Our results show that patients regularly expressed implicit cues to discuss prognosis or posed explicit questions tentatively. Consulting oncologists were mostly unresponsive to patients’ cues and cautious to prognosticate. They also seemed cautious when patients brought up the referring oncologist. Consulting oncologists checked which prognostic information patients had received from the referring oncologist, before estimating prognosis. They agreed with the first opinion or rectified discrepancies carefully. Altogether, this study exposes missed opportunities for open prognostic discussions in SOs. Consulting oncologists could explicitly explore patients’ information preferences and perceptions of prognosis. If desired, they can provide tailored, independent information to optimise patients’ prognostic awareness and informed medical decision-making. They may additionally support patients in dealing with prognosis and the uncertainties associated with it.
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Affiliation(s)
- N. C. A. van der Velden
- Amsterdam University Medical Centers, Department of Medical Psychology, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (M.B.A.v.d.K.); (V.L.); (E.M.A.S.); (I.H.); (M.A.H.)
- Amsterdam University Medical Centers, Amsterdam Public Health Research Institute, University of Amsterdam, VU University Amsterdam, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands
- Cancer Center Amsterdam, Amsterdam University Medical Centers, University of Amsterdam, VU University Amsterdam, De Boelelaan 1118, 1081 HV Amsterdam, The Netherlands
- Correspondence:
| | - M. B. A. van der Kleij
- Amsterdam University Medical Centers, Department of Medical Psychology, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (M.B.A.v.d.K.); (V.L.); (E.M.A.S.); (I.H.); (M.A.H.)
| | - V. Lehmann
- Amsterdam University Medical Centers, Department of Medical Psychology, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (M.B.A.v.d.K.); (V.L.); (E.M.A.S.); (I.H.); (M.A.H.)
- Amsterdam University Medical Centers, Amsterdam Public Health Research Institute, University of Amsterdam, VU University Amsterdam, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands
- Cancer Center Amsterdam, Amsterdam University Medical Centers, University of Amsterdam, VU University Amsterdam, De Boelelaan 1118, 1081 HV Amsterdam, The Netherlands
| | - E. M. A. Smets
- Amsterdam University Medical Centers, Department of Medical Psychology, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (M.B.A.v.d.K.); (V.L.); (E.M.A.S.); (I.H.); (M.A.H.)
- Amsterdam University Medical Centers, Amsterdam Public Health Research Institute, University of Amsterdam, VU University Amsterdam, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands
- Cancer Center Amsterdam, Amsterdam University Medical Centers, University of Amsterdam, VU University Amsterdam, De Boelelaan 1118, 1081 HV Amsterdam, The Netherlands
| | - J. M. L. Stouthard
- Department of Medical Oncology, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands;
| | - I. Henselmans
- Amsterdam University Medical Centers, Department of Medical Psychology, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (M.B.A.v.d.K.); (V.L.); (E.M.A.S.); (I.H.); (M.A.H.)
- Amsterdam University Medical Centers, Amsterdam Public Health Research Institute, University of Amsterdam, VU University Amsterdam, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands
- Cancer Center Amsterdam, Amsterdam University Medical Centers, University of Amsterdam, VU University Amsterdam, De Boelelaan 1118, 1081 HV Amsterdam, The Netherlands
| | - M. A. Hillen
- Amsterdam University Medical Centers, Department of Medical Psychology, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; (M.B.A.v.d.K.); (V.L.); (E.M.A.S.); (I.H.); (M.A.H.)
- Amsterdam University Medical Centers, Amsterdam Public Health Research Institute, University of Amsterdam, VU University Amsterdam, Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands
- Cancer Center Amsterdam, Amsterdam University Medical Centers, University of Amsterdam, VU University Amsterdam, De Boelelaan 1118, 1081 HV Amsterdam, The Netherlands
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Lehmann V, Keim MC, Nahata L, Shultz EL, Klosky JL, Tuinman MA, Gerhardt CA. Fertility-related knowledge and reproductive goals in childhood cancer survivors: short communication. Hum Reprod 2017; 32:2250-2253. [DOI: 10.1093/humrep/dex297] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 09/08/2017] [Indexed: 11/12/2022] Open
Affiliation(s)
- V Lehmann
- The Research Institute at Nationwide Children's Hospital, Center for Biobehavioral Health, 700 Children's Drive, Columbus, OH 43205, USA
- The Ohio State University, Department of Pediatrics, 700 Children's Drive, Columbus, OH 43205, USA
| | - M C Keim
- The Research Institute at Nationwide Children's Hospital, Center for Biobehavioral Health, 700 Children's Drive, Columbus, OH 43205, USA
| | - L Nahata
- The Research Institute at Nationwide Children's Hospital, Center for Biobehavioral Health, 700 Children's Drive, Columbus, OH 43205, USA
- The Ohio State University, Department of Pediatrics, 700 Children's Drive, Columbus, OH 43205, USA
| | - E L Shultz
- The Research Institute at Nationwide Children's Hospital, Center for Biobehavioral Health, 700 Children's Drive, Columbus, OH 43205, USA
| | - J L Klosky
- St. Jude Children's Research Hospital, Department of Psychology, MS740, 262 Danny Thomas Place, Memphis, TN 38105 USA
| | - M A Tuinman
- University Medical Center Groningen (UMCG), University of Groningen, Health Psychology Research Section, A. Deusinglaan 1, 9713AV Groningen, The Netherlands
| | - C A Gerhardt
- The Research Institute at Nationwide Children's Hospital, Center for Biobehavioral Health, 700 Children's Drive, Columbus, OH 43205, USA
- The Ohio State University, Department of Pediatrics, 700 Children's Drive, Columbus, OH 43205, USA
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Abstract
ABSTRACTRecently we presented a formation mechanism for micro-porous silicon which is based on a depletion of holes in the porous region due to quantum confinement. This theory allows predictions concerning the dependence of the porous morphology on the formation conditions. It is the purpose of this work to check whether these predictions are in accordance with experimental observations.
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Abstract
ABSTRACTTime-resolved studies of the visible photoluminescence in porous silicon with three different coverages of the internal surface are reported. We use aged, naturally oxidized porous Si (oxihydride), rapid thermal processed material (oxide) and samples stored in HF (pure hydride). A new, fast luminescence band in the blue-green spectral range and with response time less than 100 ns is observed at room temperature in each of the samples, although with different intensities. The observations prove that this is not an oxide-defect luminescence. We speculate on mechanisms for the origin of the fast luminescence in nanometer-size crystallites of Si.
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Linke H, Omling P, Meyer BK, Petrova-Koch V, Muschik T, Lehmann V. Electron Spin Resonance Investigations of Rapid Thermal Oxidized Porous Silicon. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-283-251] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTWe studied the defect properties present in rapid thermal oxidized porous silicon (RTOPS) by Electron Spin Resonance (ESR). Two different types of defects are distinguished, one similar to the ones observed in damaged c-Si, and in a-Si. The second one is probably related to the Pbo center at the Si/SiO2 interface. The minimum density of 1016 cm-3 is observed for the as etched and for the 900°C oxidized samples, but reaches a maximum of 8×1018 cm-3for the 600°C samples. The PL intensity anticorrelates with the defect densities, which shows that nonradiative recombination via defects is a very powerful channel in quenching the PL efficiency.
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Abstract
ABSTRACTUsing thermal effusion of H together with a weighing of the remaining Si we determine the composition of luminescing porous Si. From studies of the IR vibration spectrum and its change with effusion we. argue that the H of freshly prepared microporous Si is bound in the dihydride form SiH2. We thus obtain a surface to volume ratio and a characterisicic linear dimension of the porous surface layer. The paper concludes with some observations on photo- and electroluminescence.
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Abstract
ABSTRACTThis paper presents a model of the microporous silicon formation process which is based on hole depletion due to quantum confinement in the porous structure. This model is compared with the formation of larger porous structures (meso-, macroporous) where hole depletion is generated by a space charge region.
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Kratzer A, Handschin S, Lehmann V, Gross D, Escher F, Conde-Petit B. Hydration Dynamics of Durum Wheat Endosperm as Studied by Magnetic Resonance Imaging and Soaking Experiments. Cereal Chem 2008. [DOI: 10.1094/cchem-85-5-0660] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- A. Kratzer
- Institute of Food Science and Nutrition, ETH Zurich, CH-8092 Zurich, Switzerland
| | - S. Handschin
- Institute of Food Science and Nutrition, ETH Zurich, CH-8092 Zurich, Switzerland
| | - V. Lehmann
- Bruker-Biospin GmbH, D-76287 Rheinstetten/Germany
| | - D. Gross
- Bruker-Biospin GmbH, D-76287 Rheinstetten/Germany
| | - F. Escher
- Institute of Food Science and Nutrition, ETH Zurich, CH-8092 Zurich, Switzerland
| | - B. Conde-Petit
- Institute of Food Science and Nutrition, ETH Zurich, CH-8092 Zurich, Switzerland
- Corresponding author. Phone: +41 44 632 37 31. Fax: +41 44 632 11 23. E-mail:
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Guasch H, Lehmann V, van Beusekom B, Sabater S, Admiraal W. Influence of phosphate on the response of periphyton to atrazine exposure. Arch Environ Contam Toxicol 2007; 52:32-7. [PMID: 17061052 DOI: 10.1007/s00244-005-0186-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2005] [Accepted: 06/17/2006] [Indexed: 05/12/2023]
Abstract
After indications from the literature that nutrient concentrations may modify the toxicity of herbicides to natural periphyton communities, this study aims to provide experimental proof for atrazine. In this microcosm experiment, phosphate (P) addition did not ameliorate atrazine toxicity to periphyton. Three weeks of P addition did not increase atrazine tolerance (measured as EC50 in acute toxicity tests), whereas exposure to atrazine under conditions that were either P-limited or non-P-limited clearly reduced the development of algal biomass. Long-term exposure to atrazine induced tolerance of the community to the herbicide, and this was not influenced by P addition. Tolerance induction in this microcosm experiment has been compared with previously published field data from the same area of study and indicates that tolerance induction by atrazine may take place under atrazine exposure in streams as well as in microcosms.
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Affiliation(s)
- H Guasch
- Institute of Aquatic Ecology, Faculty of Sciences, University Girona (UdG), Campus de Montilivi, 17071, Girona, Spain.
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Lehmann V, Retzke U, Kindt J, Blau U. Effizienz der Elektropunktur (PuTENS), Akupunktur und Neuraltherapie bei der Urge-Inkontinenz. Deutsche Zeitschrift für Akupunktur 2006. [DOI: 10.1078/0415-6412-00161] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Ringseis R, Matthes B, Lehmann V, Becker K, Schöps R, Ulbrich-Hofmann R, Eder K. Peptides and hydrolysates from casein and soy protein modulate the release of vasoactive substances from human aortic endothelial cells. Biochim Biophys Acta Gen Subj 2005; 1721:89-97. [PMID: 15652183 DOI: 10.1016/j.bbagen.2004.10.005] [Citation(s) in RCA: 36] [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] [Received: 08/02/2004] [Revised: 09/27/2004] [Accepted: 10/12/2004] [Indexed: 11/16/2022]
Abstract
Food proteins were shown to affect atherogenic risk factors, which is supposed to be related to specific peptide sequences encrypted within their primary sequence. The aim of this study was to evaluate the effects of peptides and hydrolysates from two food proteins, casein and soy protein, on endothelial cell functions (cell proliferation and release of vasoactive substances). Cell proliferation was not influenced by dipeptides and most of the tripeptides, whereas several total hydrolysates from casein and soy protein inhibited cell proliferation at higher concentrations (>0.25 mg/mL; P<0.05). The release of one or more of the vasoactive substances, thromboxan B2 (stable marker of thromboxan A2), 6-keto-prostaglandin F1alpha (stable marker of prostaglandin I2), endothelin-1, and nitric oxide, was significantly influenced by the incubation with various peptides compared with control cells (P<0.05). Various hydrolysate fractions from casein and soy protein influenced the release of 6-keto-prostaglandin F1alpha and nitric oxide (P<0.05) but did not influence the release of thromboxan B2 and endothelin-1. In conclusion, the present study demonstrates that peptides and hydrolysate fractions from casein and soy protein influence endothelial cell function as evidenced by the modulation of endothelial cell proliferation and alterations in the release of vasoactive substances.
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Affiliation(s)
- R Ringseis
- Institut für Ernährungswissenschaften, Martin-Luther-Universität Halle-Wittenberg, Emil-Abderhalden-Str. 26, D-06108 Halle/Saale, Germany
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Mühlberger N, Jelinek T, Gascon J, Probst M, Zoller T, Schunk M, Beran J, Gjørup I, Behrens RH, Clerinx J, Björkman A, McWhinney P, Matteelli A, Lopez-Velez R, Bisoffi Z, Hellgren U, Puente S, Schmid ML, Myrvang B, Holthoff-Stich ML, Laferl H, Hatz C, Kollaritsch H, Kapaun A, Knobloch J, Iversen J, Kotlowski A, Malvy DJM, Kern P, Fry G, Siikamaki H, Schulze MH, Soula G, Paul M, Prat JGI, Lehmann V, Bouchaud O, Cunha SD, Atouguia J, Boecken G. Epidemiology and clinical features of vivax malaria imported to Europe: sentinel surveillance data from TropNetEurop. Malar J 2004; 3:5. [PMID: 15003128 PMCID: PMC385246 DOI: 10.1186/1475-2875-3-5] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2003] [Accepted: 03/08/2004] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Plasmodium vivax is the second most common species among malaria patients diagnosed in Europe, but epidemiological and clinical data on imported P. vivax malaria are limited. The TropNetEurop surveillance network has monitored the importation of vivax malaria into Europe since 1999. OBJECTIVES To present epidemiological and clinical data on imported P. vivax malaria collected at European level. MATERIAL AND METHODS Data of primary cases of P. vivax malaria reported between January 1999 and September 2003 were analysed, focusing on disease frequency, patient characteristics, place of infection, course of disease, treatment and differences between network-member countries. RESULTS Within the surveillance period 4,801 cases of imported malaria were reported. 618 (12.9%) were attributed to P. vivax. European travellers and immigrants were the largest patient groups, but their proportion varied among the reporting countries. The main regions of infection in descending order were the Indian subcontinent, Indonesia, South America and Western and Eastern Africa, as a group accounting for more than 60% of the cases. Regular use of malaria chemoprophylaxis was reported by 118 patients. With 86 (inter-quartile range 41-158) versus 31 days (inter-quartile range 4-133) the median symptom onset was significantly delayed in patients with chemoprophylaxis (p < 0.0001). Common complaints were fever, headache, fatigue, and musculo-skeletal symptoms. All patients survived and severe clinical complications were rare. Hospitalization was provided for 60% and primaquine treatment administered to 83.8% of the patients, but frequencies varied strongly among reporting countries. CONCLUSIONS TropNetEurop data can contribute to the harmonization of European treatment policies.
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Affiliation(s)
- N Mühlberger
- Institute of Tropical Medicine, Humboldt University, Berlin, Germany
| | - T Jelinek
- Institute of Tropical Medicine, Humboldt University, Berlin, Germany
| | - J Gascon
- Secció Medicina Tropical, Hospital Clinic Barcelona – IDIBAPS., Barcelona, Spain
| | - M Probst
- Department of Medicine (Infectious Diseases), Charité, Humboldt University, Berlin, Germany
| | - T Zoller
- Department of Medicine (Infectious Diseases), Charité, Humboldt University, Berlin, Germany
| | - M Schunk
- Department of Infectious Diseases and Tropical Medicine, University of Munich, Germany
| | - J Beran
- Department of Infectious Diseases, University Hospital Hradec Králové, Czech Republic
| | - I Gjørup
- Department of Infectious Diseases, Rigshospitalet, University of Copenhagen; Denmark
| | - RH Behrens
- Hospital for Tropical Diseases, London, UK
| | - J Clerinx
- Clinical Services, Prins Leopold Instituut voor Tropische Geneeskunde, Antwerp; Belgium
| | - A Björkman
- Department of Medicine, Unit of Infectious Diseases, Karolinska Institute, Stockholm, Sweden
| | - P McWhinney
- Infection and Tropical Medicine, Bradford Royal Infirmary, Bradford, UK
| | - A Matteelli
- Clinica di Malattie Infettive e Tropicali, Universitá di Brescia, Italy
| | - R Lopez-Velez
- Infectious Diseases–Microbiology Department, Tropical Medicine & Clinical Parasitology Unit, Hospital Ramon y Cajal, Madrid, Spain
| | - Z Bisoffi
- Centro per le Malattie Tropicali, Ospedale S. Cuore, Negrar Verona, Italy
| | - U Hellgren
- Division of Infectious Diseases, Huddinge University Hospital, Karolinska Institute, Stockholm, Sweden
| | - S Puente
- Sección de Medicina Tropical-Servicio de Enfermedades Infecciosas, Hospital Carlos III- Instituto de Salud Carlos III, Madrid, Spain
| | - ML Schmid
- Department of Infection & Tropical Medicine, Newcastle General Hospital, Newcastle- upon-Tyne, UK
| | - B Myrvang
- Department of Infectious Diseases, Ullevaal University Hospital, Oslo, Norway
| | | | - H Laferl
- 4. Medizinische Abteilung mit Infektions- und Tropenmedizin, Kaiser-Franz-Josef-Spital der Stadt Wien, Vienna, Austria
| | - C Hatz
- Swiss Tropical Institute, Basel, Switzerland
| | - H Kollaritsch
- Abteilung fur spezifische Prophylaxe und Tropenmedizin am Institut für Pathophysiologie, University of Vienna, Austria
| | - A Kapaun
- Institut für Tropenhygiene und öffentliches Gesundheitswesen, Universität Heidelberg, Germany
| | - J Knobloch
- Institut für Tropenmedizin, Universitätsklinikum Tübingen, Germany
| | - J Iversen
- Department of Infectious Diseases, Hvidovre Hospital, Hvidovre, Denmark
| | - A Kotlowski
- Department of Tropical Medicine and Epidemiology, Medical University of Gdansk, Interfacultary Institute of Maritime and Tropical Medicine in Gdynia, Poland
| | - DJM Malvy
- Hôpital St André-CHU, Bordeaux, France
| | - P Kern
- Sektion Infektiologie und Klinische Immunologie, Universität Ulm, Germany
| | - G Fry
- Tropical Medical Bureau, Dublin, Ireland
| | - H Siikamaki
- Department of Medicine, Division of Infectious Diseases, Helsinki University Central Hospital, Helsinki, Finland
| | - MH Schulze
- 2. Klinik für Innere Medizin, Städtische Kliniken "St. Georg", Leipzig, Germany
| | - G Soula
- Department of Infectious and Tropical Diseases, Hopital Nord CHU, Marseille, France
| | - M Paul
- Department and Clinic of Tropical and Parasitic Diseases, Karol Marcinkowski University of Medical Sciences, Poznan, Poland
| | - J Gómez i Prat
- Unitat de Malalties Tropicals, Importades i Vacunacions Internationales, Institut Català de la Salut, Barcelona, Spain
| | - V Lehmann
- Centre for Tropical Medicine and Imported Infectious Diseases, Haukeland University Hospital, Bergen, Norway
| | - O Bouchaud
- Consultation de médecine tropicale, Hôpital Avicenne, Bobigny, France
| | - S da Cunha
- Consulta de Medicina do Viajante, Departamento de Doenças Infecciosas, Hospital Universitário, Coimbra, Portugal
| | - J Atouguia
- Instituto de Higiena e Medicina Tropical, Universidade Nova de Lisboa, Lisbon, Portugal
| | - G Boecken
- The German Navy Institute for Maritime Medicine, Center for Applied Tropical Medicine and Infectious Diseases Epidemiology, Kronshagen, Germany
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Abstract
A considerable risk of life-threatening injury is inherent to bullfighting. Thus, a unique form of emergency treatment has evolved over recent decades of organized bull-fighting. Today bullfight arenas in larger cities are equipped with emergency facilities including fully furnished operating rooms. During a fiesta these facilities are run by a medical team consisting of three surgeons, one intensive care specialist, and one anesthesiologist with their supporting medical personnel. In smaller arenas or villages immediate care units consist of emergency vehicles, and a mobile container equipped with a fully functional operating room. Of all toreros the matadores including the novilleros are most often injured in 56 % of cases. This rate decreases for banderillos (30 %), and for picadores (14 %). Parts of the body that are most frequently affected are thighs, and the inguinal region (54 %). Head and neck injuries are seen in 19 %, and 12 % of cases present with open abdominal wounds including liver or gastrointestinal tract traumas. 10 % of injuries affect the thorax, and 4 % the pelvic floor. The particular form of organised medical treatment for bullfighters in Spain has only developed since the nineteen-thirties. In 1972 a scientific society for bullfight surgery was founded in Spain by specialized surgeons, and immediate care specialists holding a first convention that year. The society is continuously striving to improve technical and logistical aspects of immediate medical care for injured bullfighters.
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Affiliation(s)
- V Lehmann
- Allgemeines Krankenhaus Altona, Hamburg
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21
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Abstract
To measure MR renograms, cortical and medullary kidney signal intensity evolution is followed after contrast agent injection. To obtain an accurate quantitative signal measurement, the use of a reference signal is necessary to correct the potential MRI system variations in time. The ERETIC method (Electronic Reference To access In vivo Concentrations) provides an electronic reference signal. It is synthesized as an amplitude modulated RF pulse applied during the acquisition. The ERETIC method was as precise as the external tube reference method but presents major advantages like its free adjustability (shape, location and magnitude) to the characteristics of the organ studied as well as its not taking room inside the magnet. Even though ERETIC showed a very good intrinsic stability, systems' variations still affect its signal in the same way as real NMR signals are affected. This method can be easily implemented on any imaging system with two RF channels.
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22
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Hogers B, Gross D, Lehmann V, de Groot HJ, de Roos A, Gittenberger-de Groot AC, Poelmann RE. Magnetic resonance microscopy at 17.6-Tesla on chicken embryos in vitro. J Magn Reson Imaging 2001; 14:83-6. [PMID: 11436219 DOI: 10.1002/jmri.1155] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [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: 11/10/2022] Open
Abstract
The non-destructive nature and the rapid acquisition of a three-dimensional image makes magnetic resonance microscopy (MRM) very attractive and suitable for functional imaging investigations. We explored the use of an ultra high magnetic field for MRM to increase image quality per image acquisition time. Improved image quality was characterized by a better signal-to-noise ratio (SNR), better image contrast, and higher resolution compared to images obtained at lower magnetic field strengths. Fixed chicken embryos at several stages of development were imaged at 7.0-T (300 MHz) and at 17.6-T (750 MHz). Maximum intensity projection resulted in three-dimensional vascular images with ample detail of the embryonic vasculature. We showed that at 750 MHz frequency, an image with approximately three times better SNR can be obtained by T1-weighting using a standard gadolinium contrast agent, compared to the same measurement at 300 MHz. The image contrast improved by around 20 percent and the contrast-to-noise ratio improved by almost a factor of 3.5. Smaller blood vessels of the vascular system were identified at the high field, which indicates a better image resolution. Thus, ultra high field is beneficial for MRM and opens new areas for functional imaging research, in particular when SNR, resolution, and contrast are limited by acquisition time.
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Affiliation(s)
- B Hogers
- Department of Anatomy, Leiden University Medical Center, Leiden, The Netherlands
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23
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Abstract
Magnetic resonance microscopy (MRM) was used to study mouse embryonic development in utero. MRM is a non-invasive imaging technique to study normal and abnormal embryonic development. To overcome image blurring as a result of embryonic movement, fast imaging sequences were used (less than 1 min scanning time). Clear morphologic proton images were obtained by diffusion spin echo and by rapid acquisition with relaxation enhancement (RARE), revealing living mouse embryos with great anatomical detail. In addition, functional information about embryonic blood flow could be obtained, in the absence of a contrast agent. This was achieved by combining two imaging sequences, RARE and very fast gradient echo. We expect that MRM will soon become a feasible method to study longitudinally both normal and abnormal (transgenic) mouse development.
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Affiliation(s)
- B Hogers
- Department of Anatomy, Leiden University Medical Center, Leiden, The Netherlands
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24
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Kosaka M, Owatari N, Seo Y, Kawakubo H, Harada S, Katsumata T, Ida H, Lehmann V. In vivo NMR micro-imaging of kidney and liver of mouse at 9.4 T. Jpn J Physiol 2000; 50:463-7. [PMID: 11082546 DOI: 10.2170/jjphysiol.50.463] [Citation(s) in RCA: 10] [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] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
NMR micro-images of the kidney and liver were measured at 9.4 T in intact mouse, schistosoma Mansoni-infected mouse, and lupus nephritis in an MRL/lpr mouse. High-field NMR imaging has the advantages of sensitivity, spatial resolution, and tissue contrasts based on longitudinal and transverse relaxations, magnetic susceptibility differences and blood flow.
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Affiliation(s)
- M Kosaka
- Department of Environmental Physiology, School of Medicine, Nagasaki University, Nagasaki, 852-8523 Japan
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25
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Lehmann V, Tubbing GM, Admiraal W. Induced metal tolerance in microbenthic communities from three lowland rivers with different metal loads. Arch Environ Contam Toxicol 1999; 36:384-391. [PMID: 10227857 DOI: 10.1007/pl00006610] [Citation(s) in RCA: 8] [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] [Indexed: 05/23/2023]
Abstract
The response of microbenthic communities to sustained metal stress was studied in three lowland rivers with different levels of pollution. Tolerance against zinc and cadmium was determined in short-term toxicity tests with microbenthic assemblages colonizing glass discs. Photosynthetic activity served as an endpoint in tests for algae, whereas for bacteria thymidine incorporation was determined. For bacterial assemblages from unpolluted locations, EC50 values in short-term tests ranged between 6.7 and 56.2 &mgr;M zinc, and 8.7 and 25.5 &mgr;M cadmium, respectively. Bacterial assemblages from the two most polluted sites were significantly more tolerant for zinc (EC50: 994 &mgr;M and >1,000 &mgr;M) and cadmium (EC50: 218 &mgr;M and 154 &mgr;M). Results indicated a shift in community composition toward pollution-adapted organisms when a threshold concentration of 1 &mgr;M zinc is exceeded. Although an increasing community tolerance was also indicated for algae, EC50 values for microbenthic algae from all sites exceeded in most cases the highest metal concentrations tested (Zn: 1,000 &mgr;M; Cd: 320 &mgr;M). Since species composition of algal assemblages was found to change at much lower metal levels, it is concluded that short-term toxicity tests measuring photosynthesis inhibition do not reflect well the long-term effects of these metals. Toxic effects of metals on both algal and bacterial assemblages are attenuated by precipitation and complexing capacities of the biofilm.
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Affiliation(s)
- V Lehmann
- University of Amsterdam, ARISE, Department of Ecotoxicology, Kruislaan 320, 1098 SM Amsterdam, The Netherlands
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26
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Ushmorov A, Ratter F, Lehmann V, Dröge W, Schirrmacher V, Umansky V. Nitric-oxide-induced apoptosis in human leukemic lines requires mitochondrial lipid degradation and cytochrome C release. Blood 1999; 93:2342-52. [PMID: 10090945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
We have previously shown that nitric oxide (NO) stimulates apoptosis in different human neoplastic lymphoid cell lines through activation of caspases not only via CD95/CD95L interaction, but also independently of such death receptors. Here we investigated mitochondria-dependent mechanisms of NO-induced apoptosis in Jurkat leukemic cells. NO donor glycerol trinitrate (at the concentration, which induces apoptotic cell death) caused (1) a significant decrease in the concentration of cardiolipin, a major mitochondrial lipid; (2) a downregulation in respiratory chain complex activities; (3) a release of the mitochondrial protein cytochrome c into the cytosol; and (4) an activation of caspase-9 and caspase-3. These changes were accompanied by an increase in the number of cells with low mitochondrial transmembrane potential and with a high level of reactive oxygen species production. Higher resistance of the CD95-resistant Jurkat subclone (APO-R) cells to NO-mediated apoptosis correlated with the absence of cytochrome c release and with less alterations in other mitochondrial parameters. An inhibitor of lipid peroxidation, trolox, significantly suppressed NO-mediated apoptosis in APO-S Jurkat cells, whereas bongkrekic acid (BA), which blocks mitochondrial permeability transition, provided only a moderate antiapoptotic effect. Transfection of Jurkat cells with bcl-2 led to a complete block of apoptosis due to the prevention of changes in mitochondrial functions. We suggest that the mitochondrial damage (in particular, cardiolipin degradation and cytochrome c release) induced by NO in human leukemia cells plays a crucial role in the subsequent activation of caspase and apoptosis.
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Affiliation(s)
- A Ushmorov
- Division of Immunochemistry, Tumor Immunology Program, German Cancer Research Center, Heidelberg, Germany
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27
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Ratter F, Gassner C, Shatrov V, Lehmann V. Modulation of tumor necrosis factor-alpha-mediated cytotoxicity by changes of the cellular methylation state: mechanism and in vivo relevance. Int Immunol 1999; 11:519-27. [PMID: 10323204 DOI: 10.1093/intimm/11.4.519] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [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: 01/30/2023] Open
Abstract
A combination of adenosine (Ado) and homocysteine (Homo) enhances tumor necrosis factor (TNF)-alpha cytotoxicity in vitro and in vivo in several tumor cells. Ado and Homo at concentrations that enhanced TNF-alpha-mediated cytotoxicity accumulated S-adenosylhomocysteine (AdoHcy) and as consequence decreased the cellular methylation state, i.e. the ratio of S-adenosylmethionine to AdoHcy. This decrease led to inhibition of the isoprenylcysteine carboxyl methyltransferase (MTase), an enzyme that catalyzes carboxyl methylation of C-terminal cysteine residues on isoprenylated proteins. The effect of Ado and Homo on TNF-alpha cytotoxicity was at least partly mimicked by S-farnesylthioacetic acid, a selective inhibitor of the isoprenylcysteine carboxyl MTase, suggesting involvement of methylations of prenylated proteins in TNF-alpha-mediated cytotoxicity. Blockage of methylation reactions was associated with an enhancement of the TNF-alpha-induced disruption of the mitochondrial membrane potential (delta psi(m)). In nude mice, a combination of Ado, Homo and TNF-alpha led to TNF-alpha-induced hemorrhagic necrosis and growth inhibition of TNF-sensitive L929 tumors, whereas little effect was observed with TNF-alpha alone. Even more important, the TNF-resistant L929 M1 tumors were rendered TNF-sensitive by the combined action of Ado and Homo. We conclude that Ado and Homo together enhance the effectiveness of TNF-alpha in vitro and in vivo, results that may have therapeutic implications.
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Affiliation(s)
- F Ratter
- German Cancer Research Center, Division of Immunochemistry, Heidelberg
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28
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Lehmann V. [Is life more?]. Tidsskr Nor Laegeforen 1998; 118:3832. [PMID: 9816954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
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29
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Lehmann V. [Physicians and drug industry]. Tidsskr Nor Laegeforen 1998; 118:1912. [PMID: 9638065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
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30
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Hehner SP, Heinrich M, Bork PM, Vogt M, Ratter F, Lehmann V, Schulze-Osthoff K, Dröge W, Schmitz ML. Sesquiterpene lactones specifically inhibit activation of NF-kappa B by preventing the degradation of I kappa B-alpha and I kappa B-beta. J Biol Chem 1998; 273:1288-97. [PMID: 9430659 DOI: 10.1074/jbc.273.3.1288] [Citation(s) in RCA: 314] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Extracts from certain Mexican Indian medicinal plants used in traditional indigenous medicine for the treatment of inflammations contain sequiterpene lactones (SLs), which specifically inhibit the transcription factor NF-kappa B (Bork, P. M., Schmitz, M. L., Kuhnt, M., Escher, C., and Heinrich, M. (1997) FEBS Lett. 402, 85-90). Here we show that SLs prevented the activation of NF-kappa B by different stimuli such as phorbol esters, tumor necrosis factor-alpha, ligation of the T-cell receptor, and hydrogen peroxide in various cell types. Treatment of cells with SLs prevented the induced degradation of I kappa B-alpha and I kappa B-beta by all these stimuli, suggesting that they interfere with a rather common step in the activation of NF-kappa B. SLs did neither interfere with DNA binding activity of activated NF-kappa B nor with the activity of the protein tyrosine kinases p59fyn and p60arc. Micromolar amounts of SLs prevented the induced expression of the NF-kappa B target gene intracellular adhesion molecule 1. Inhibition of NF-kappa B by SLs resulted in an enhanced cell killing of murine fibroblast cells by tumor necrosis factor-alpha. SLs lacking an exomethylene group in conjugation with the lactone function displayed no inhibitory activity on NF-kappa B. The analysis of the cellular redox state by fluorescence-activated cell sorter showed that the SLs had no direct or indirect anti-oxidant properties.
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Affiliation(s)
- S P Hehner
- Department of Immunochemistry, German Cancer Research Center (DKFZ), Heidelberg, Germany
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31
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Birner A, Grüning U, Ottow S, Schneider A, Müller F, Lehmann V, Föll H, Gösele U. Macroporous Silicon: A Two-Dimensional Photonic Bandgap Material Suitable for the Near-Infrared Spectral Range. ACTA ACUST UNITED AC 1998. [DOI: 10.1002/(sici)1521-396x(199801)165:1<111::aid-pssa111>3.0.co;2-t] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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32
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Shatrov VA, Lehmann V, Chouaib S. Sphingosine-1-phosphate mobilizes intracellular calcium and activates transcription factor NF-kappa B in U937 cells. Biochem Biophys Res Commun 1997; 234:121-4. [PMID: 9168973 DOI: 10.1006/bbrc.1997.6598] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Sphingosine-1-phosphate (SPP), a metabolite of sphingolipids, has been implicated as a second messenger in cell growth regulation and signal transduction via calcium mobilization from internal stores. This study shows that SPP mobilizes intracellular calcium in U937 cells and demonstrates for the first time the ability of SPP to activate the transcription factor NF-kappa B in these cells. Furthermore, calcium release from the internal stores by thapsigargin (TG), an inhibitor of the endoplasmic reticulum Ca2+ pump, was associated with activation of NF-kappa B. Moreover, we have shown that while an intracellular calcium chelator BAPTA/AM was able to inhibit both SPP- and TG-induced NF-kappa B activation, it had no effect on TNF-induced NF-kappa B activation. In addition, SPP-induced NF-kappa B activation was blocked both by cyclosporin A, known to inhibit calcineurin phosphatase activity, and by the antioxidant butylated hydroxyanisole. These observations suggest that intracellular calcium mobilization is required for SPP-induced NF-kappa B activation, which may involve calcineurin- and redox-dependent mechanisms.
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Affiliation(s)
- V A Shatrov
- CJF 94-11 INSERM Cytokines et Immunitè Antitumorale, Institut Gustave-Roussy, Villejuif, France
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Shatrov VA, Boelaert JR, Chouaib S, Dröge W, Lehmann V. Iron chelation decreases human immunodeficiency virus-1 Tat potentiated tumor necrosis factor-induced NF-kappa B activation in Jurkat cells. Eur Cytokine Netw 1997; 8:37-43. [PMID: 9110146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
TNF-alpha stimulates HIV-1 replication via activation of the transcription factor NF-kappa B. TNF-mediated activation of NF-kappa B is known to involve the intracellular formation of reactive oxygen intermediates (ROIs). We recently demonstrated that HIV-1 Tat protein potentiates TNF-induced NF-kappa B activation by downregulation of manganese-dependent superoxide dismutase (MnSOD), shifting the cellular redox state towards pro-oxidative conditions. This study shows that treatment of Jurkat cells with iron chelator deferoxamine (DFO) strongly decreases HIV-1 Tat-potentiated TNF-induced NF-kappa B activation but does not modify NF-kappa B activation by TNF-alpha. The ability of iron chelators to reduce Tat-potentiated TNF-induced NF-kappa B binding activity suggests that iron and intracellular hydroxyl radicals (OH.) are required for Tat effect. Moreover, we have shown that exogenously generated OH. markedly enhanced TNF-induced NF-kappa B activation in a dose-dependent manner while was not sufficient to trigger activation of NF-kappa B by itself. In addition, iron chelators had no effect either on MnSOD activity or on the decrease of this activity by Tat. Iron chelators had also no effect on the ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG), but could elevate the GSH:GSSG ratio decreased by Tat protein. These observations suggest that the formation of intracellular OH. in the presence of iron ions play a major role in HIV-1 Tat enhancement of TNF-induced NF-kappa B activation and that iron chelation may protect Jurkat T cells, at least in part, against oxidative stress induced by Tat.
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Affiliation(s)
- V A Shatrov
- CJF 94-11 INSERM Cytokines et Immunité Antitumorale, Institut Gustave-Roussy, Villejuif, France
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Shatrov VA, Ratter F, Gruber A, Dröge W, Lehmann V. HIV type 1 glycoprotein 120 amplifies tumor necrosis factor-induced NF-kappa B activation in Jurkat cells. AIDS Res Hum Retroviruses 1996; 12:1209-16. [PMID: 8870842 DOI: 10.1089/aid.1996.12.1209] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
This article demonstrates that human immunodeficiency virus type 1 (HIV-1) gp120 amplifies the activity of tumor necrosis factor alpha (TNF-alpha), a cytokine that stimulates HIV-1 replication through activation of NF-kappa B. In CD4-positive Jurkat cells, gp120 potentiates TNF-induced NF-kappa B activation. TNF-mediated activation of NF-kappa B is known to involve the intracellular formation of reactive oxygen intermediates (ROIs). Accordingly, we examined the influence of gp120 on the cellular redox state. We found that gp 120-modulated TNF-induced NK-kappa B activation was inhibited by the antioxidant butylated hydroxyanisole, indicating the involvement of redox-dependent mechanisms. In addition, we showed that gp120 induces intracellular formation of hydrogen peroxide, which is accompanied by a decrease in the ratio of glutathione to glutathione disulfide. In contrast, in the p56lck-deficient J.CaM1.6 T cell line, a derivative of the Jurkat cell line, gp120 was unable to stimulate hydrogen peroxide, to decrease the ratio of GSH to GSSG, and has no effect on TNF-induced NF-kappa B activation. This demonstrated that p56lck protein tyrosine kinase plays an active role in transmitting a signal that increases the oxidative state of the cell and as a consequence amplifies TNF-mediated NF-kappa B DNA binding. We have demonstrated that Tat protein decreased both the Mn-dependent superoxide dismutase (MnSOD) and the cellular glutathione content (GSH). Here we show that, in contrast to Tat, gp120 is unable to inhibit activity and expression of MnSOD and to decrease GSH content. Taken together, our data suggest that gp120 potentiates TNF-induced NF-kappa B activation by stimulating a signal pathway that involves p56lck and the increased formation of reactive oxygen intermediates such as H2O2. These findings may be relevant for the regulation of HIV-1 replication in T cells.
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Affiliation(s)
- V A Shatrov
- Division of Immunochemistry, Deutsches Krebsforschungszentrum, Heidelberg, Germany
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35
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Ratter F, Germer M, Fischbach T, Schulze-Osthoff K, Peter ME, Dröge W, Krammer PH, Lehmann V. S-adenosylhomocysteine as a physiological modulator of Apo-1-mediated apoptosis. Int Immunol 1996; 8:1139-47. [PMID: 8757959 DOI: 10.1093/intimm/8.7.1139] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
APO-1/Fas (CD95) is a member of the tumor necrosis factor/nerve growth factor receptor superfamily and mediates apoptosis in various cell types. Here we show that L929 cells, expressing human APO-1 treated with agonistic antibodies (anti-APO-1), elicit an early and transient increase of S-adenosylhomocysteine (AdoHcy), a potent inhibitor of S-adenosylmethionine (AdoMet)-dependent methylation reactions. In contrast, anti-APO-1 did not induce an AdoHcy increase in L929-APO-1 Delta4 cells expressing a C-terminally truncated APO-1 lacking part of the 'death domain' known to be required for the transduction of apoptotic signals. Addition of adenosine and D, L-homocysteine also led to an increase of cellular AdoHcy thus enhancing anti-APO-1-induced killing of L929-APO-1 cells. Treatment with anti-APO-1 also induced release of arachidonic acid from phospholipids: this effect was augmented by elevated levels of AdoHcy. In contrast, AdoHcy had only a minor effect on anti-APO-1-mediated DNA fragmentation. These findings suggest that AdoHcy functions as a physiological modulator of APO-1-mediated cell death in L929 cells and enhances anti-APO-1-induced cell killing at least partially by acting via the phospholipase A2 pathway.
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Affiliation(s)
- F Ratter
- Division of Immunochemistry, Deutsches Krebsforschungszentrum, 69120 Heidelberg, Germany
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36
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Umansky V, Shatrov VA, Lehmann V, Schirrmacher V. Induction of NO synthesis in macrophages by Newcastle disease virus is associated with activation of nuclear factor-kappa B. Int Immunol 1996; 8:491-8. [PMID: 8671635 DOI: 10.1093/intimm/8.4.491] [Citation(s) in RCA: 38] [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: 02/01/2023] Open
Abstract
Newcastle disease virus (NDV) has received much attention recently because of its non-specific immune stimulating potential and its various anti-tumor activities. Here we describe that NDV induces synthesis of NO and causes an activation of nuclear factor-kappa B (NF-kappa B) in murine macrophages. These reactions were part of an activation process which included also stimulation of adenosine deaminase and inhibition of 5'-nucleotidase. NDV-mediated NO synthesis and NF-kappa B activation were blocked by an antioxidant (butylated hydroxyanisole), by an inhibitor of protein tyrosine kinase (genistein) and of protein kinase A (H-89), but not by an inhibitor of protein kinase C (staurosporin). These data suggest that signalling requirements of NF-kappa B activation and NO production in NDV-treated macrophages are similar.
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Affiliation(s)
- V Umansky
- Tumor Immunology Program, German Cancer Research Center, Heidelberg, Germany
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37
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Lehmann V. [Working condition of physicians during their graduate education]. Tidsskr Nor Laegeforen 1996; 116:658. [PMID: 8658467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
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38
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Abstract
A 1H-nuclear magnetic resonance (NMR) microscopy method was utilized for the first time to determine the porosity distribution of physically intact tablets. The main advantage of this newly developed method was that porosity cross sections through whole tablets or specific locations could be obtained without mechanically destroying the tested tablet. This was achieved by filling tablet cavities with silicone oil under vacuum. The amount of silicone oil locally within the tablet was then determined by 1H-NMR microscopy, revealing the inverse inner structure. To reduce the measuring time, a paramagnetic gadolinium complex was added to the silicone oil. The cross sectional signals produced by 1H-NMR microscopy through the tablet were transformed into a color image by a specially designed computer graphic program. To improve the signal-noise ratio an algorithm of 3D-filtering was introduced. The maximal spatial resolution achieved with this method was about 95 microns for a cube's edge length corresponding to some 380,000 positions in a 9-mm-diameter compression-coated tablet. Uneven porosity distributions within tablets, cracks, or cavities could be visualized with this newly developed method. Different compaction mechanisms were observed with plastic- or brittle-type tablets. The different states of densification during compaction of powders could be detected. The integrity of compression coatings was determined to be dependent on the pressure load and the location of the core within the coat.
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Affiliation(s)
- G Nebgen
- Pharma Operations Manufacturing, POMF-DL, F. Hoffmann-La Roche LTD, Basel, Switzerland
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39
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Westendorp MO, Shatrov VA, Schulze-Osthoff K, Frank R, Kraft M, Los M, Krammer PH, Dröge W, Lehmann V. HIV-1 Tat potentiates TNF-induced NF-kappa B activation and cytotoxicity by altering the cellular redox state. EMBO J 1995; 14:546-54. [PMID: 7859743 PMCID: PMC398112 DOI: 10.1002/j.1460-2075.1995.tb07030.x] [Citation(s) in RCA: 300] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
This study demonstrates that human immunodeficiency virus type 1 (HIV-1) Tat protein amplifies the activity of tumor necrosis factor (TNF), a cytokine that stimulates HIV-1 replication through activation of NF-kappa B. In HeLa cells stably transfected with the HIV-1 tat gene (HeLa-tat cells), expression of the Tat protein enhanced both TNF-induced activation of NF-kappa B and TNF-mediated cytotoxicity. A similar potentiation of TNF effects was observed in Jurkat T cells and HeLa cells treated with soluble Tat protein. TNF-mediated activation of NF-kappa B and cytotoxicity involves the intracellular formation of reactive oxygen intermediates. Therefore, Tat-mediated effects on the cellular redox state were analyzed. In both T cells and HeLa cells HIV-1 Tat suppressed the expression of Mn-dependent superoxide dismutase (Mn-SOD), a mitochondrial enzyme that is part of the cellular defense system against oxidative stress. Thus, Mn-SOD RNA protein levels and activity were markedly reduced in the presence of Tat. Decreased Mn-SOD expression was associated with decreased levels of glutathione and a lower ratio of reduced:oxidized glutathione. A truncated Tat protein (Tat1-72), known to transactivate the HIV-1 long terminal repeat (LTR), no longer affected Mn-SOD expression, the cellular redox state or TNF-mediated cytotoxicity. Thus, our experiments demonstrate that the C-terminal region of HIV-1 Tat is required to suppress Mn-SOD expression and to induce pro-oxidative conditions reflected by a drop in reduced glutathione (GSH) and the GSH:oxidized GSH (GSSG) ratio.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M O Westendorp
- Division of Immunogenetics, German Cancer Research Center, Heidelberg
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40
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Bergmann S, Shatrov V, Ratter F, Schiemann S, Schulze-Osthoff K, Lehmann V. Adenosine and homocysteine together enhance TNF-mediated cytotoxicity but do not alter activation of nuclear factor-kappa B in L929 cells. J Immunol 1994; 153:1736-43. [PMID: 8046241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This paper shows that a combination of adenosine and homocysteine potentiates TNF-alpha-mediated cytotoxicity, but does not modulate activation of NF-kappa B transcription factor controlling the expression of various TNF-alpha-inducible genes. Adenosine and homocysteine at concentrations (1 mM each) that enhance TNF-alpha-induced cytotoxicity accumulate S-adenosyl-L-homocysteine (AdoHcy), a potent inhibitor of S-adenosyl-L-methionine-dependent methylation reactions. In addition, preloading L929 cells with AdoHcy resulted in enhanced responses to TNF-alpha, suggesting that AdoHcy potentiates TNF-alpha-induced cytotoxicity. Moreover, the combination of adenosine and homocysteine changed the dependency of the TNF-alpha-mediated cytolysis on reactive oxygen intermediates. In the absence of adenosine and homocysteine TNF-alpha-mediated cytotoxicity was inhibited by antioxidants such as butylated hydroxyanisole and pyrrolidine dithiocarbamate. In the presence of adenosine and homocysteine, however, TNF-alpha-mediated cytotoxicity is not inhibited by these antioxidants. A L929 subclone, defective in the respiratory chain, resisted the cytotoxic action of TNF-alpha, but was rendered TNF-alpha sensitive in the presence of adenosine and homocysteine. Unlike TNF-alpha-mediated cytotoxicity, the TNF-alpha-induced activation of NF-kappa B was inhibited by antioxidants regardless whether adenosine and homocysteine were present or absent in the culture medium. In conclusion, a combination of adenosine and homocysteine selectively modulates TNF-alpha-mediated cytotoxicity without changing the TNF-alpha-induced activation of NF-kappa B. Our results could facilitate the development of strategies that permit dissection of cytotoxic and gene-activating pathways.
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Affiliation(s)
- S Bergmann
- German Cancer Research Center, Division of Immunochemistry, Heidelberg
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41
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Bergmann S, Shatrov V, Ratter F, Schiemann S, Schulze-Osthoff K, Lehmann V. Adenosine and homocysteine together enhance TNF-mediated cytotoxicity but do not alter activation of nuclear factor-kappa B in L929 cells. The Journal of Immunology 1994. [DOI: 10.4049/jimmunol.153.4.1736] [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] [Indexed: 01/01/2023]
Abstract
Abstract
This paper shows that a combination of adenosine and homocysteine potentiates TNF-alpha-mediated cytotoxicity, but does not modulate activation of NF-kappa B transcription factor controlling the expression of various TNF-alpha-inducible genes. Adenosine and homocysteine at concentrations (1 mM each) that enhance TNF-alpha-induced cytotoxicity accumulate S-adenosyl-L-homocysteine (AdoHcy), a potent inhibitor of S-adenosyl-L-methionine-dependent methylation reactions. In addition, preloading L929 cells with AdoHcy resulted in enhanced responses to TNF-alpha, suggesting that AdoHcy potentiates TNF-alpha-induced cytotoxicity. Moreover, the combination of adenosine and homocysteine changed the dependency of the TNF-alpha-mediated cytolysis on reactive oxygen intermediates. In the absence of adenosine and homocysteine TNF-alpha-mediated cytotoxicity was inhibited by antioxidants such as butylated hydroxyanisole and pyrrolidine dithiocarbamate. In the presence of adenosine and homocysteine, however, TNF-alpha-mediated cytotoxicity is not inhibited by these antioxidants. A L929 subclone, defective in the respiratory chain, resisted the cytotoxic action of TNF-alpha, but was rendered TNF-alpha sensitive in the presence of adenosine and homocysteine. Unlike TNF-alpha-mediated cytotoxicity, the TNF-alpha-induced activation of NF-kappa B was inhibited by antioxidants regardless whether adenosine and homocysteine were present or absent in the culture medium. In conclusion, a combination of adenosine and homocysteine selectively modulates TNF-alpha-mediated cytotoxicity without changing the TNF-alpha-induced activation of NF-kappa B. Our results could facilitate the development of strategies that permit dissection of cytotoxic and gene-activating pathways.
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Affiliation(s)
- S Bergmann
- German Cancer Research Center, Division of Immunochemistry, Heidelberg
| | - V Shatrov
- German Cancer Research Center, Division of Immunochemistry, Heidelberg
| | - F Ratter
- German Cancer Research Center, Division of Immunochemistry, Heidelberg
| | - S Schiemann
- German Cancer Research Center, Division of Immunochemistry, Heidelberg
| | - K Schulze-Osthoff
- German Cancer Research Center, Division of Immunochemistry, Heidelberg
| | - V Lehmann
- German Cancer Research Center, Division of Immunochemistry, Heidelberg
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42
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Lehmann V. [Physicians who come to Norway as refugees]. Tidsskr Nor Laegeforen 1993; 113:3165. [PMID: 8273049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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43
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Guttormsen HK, Bjerknes R, Naess A, Lehmann V, Halstensen A, Sørnes S, Solberg CO. Cross-reacting serum opsonins in patients with meningococcal disease. Infect Immun 1992; 60:2777-83. [PMID: 1612745 PMCID: PMC257234 DOI: 10.1128/iai.60.7.2777-2783.1992] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [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: 12/27/2022] Open
Abstract
We have examined the opsonic activity of sera from patients with Neisseria meningitidis (B:15:P1.16) infections against different meningococcal strains, using flow cytometry and luminol-enhanced chemiluminescence. A marked increase in the phagocytosis of ethanol-fixed meningococcal strains of different serogroups, serotypes, and serosubtypes was demonstrated in the presence of convalescence sera compared with acute sera. Convalescence sera also caused a significant increase of leukocyte oxidative metabolism during phagocytosis, as measured by luminol-enhanced chemiluminescence. The sera contained a broad range of opsonins cross-reacting with serogroup A, B, C, W-135, and Y meningococci of different serotypes and serosubtypes, indicating that the cross-reacting opsonins recognized surface epitopes other than those determined by current serotyping schemes.
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Affiliation(s)
- H K Guttormsen
- Medical Department B, University of Bergen, Haukeland Hospital, Norway
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44
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Sjursen H, Lehmann V, Naess A, Hervig T, Flø RW, Maehle B, Halstensen AI, Frøholm LO. Monocyte phagocytosis of opsonized Neisseria meningitidis serogroup B. APMIS 1992; 100:209-20. [PMID: 1562314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The chemiluminescence (CL) was examined when peripheral blood monocytes were incubated with opsonized Neisseria meningitidis, serogroup B, serotype 15:P1.16 or serotype 2a:P1.2. The monocytes were separated from a mononuclear cell suspension by an immunomagnetic negative selection technique using magnetic polystyrene microspheres coated with monoclonal antibodies specific for T and B lymphocytes. More than 90% of the lymphocytes were removed, yielding a suspension containing 93% monocytes. Optimal sensitivity for phagocytosis was obtained using 1% serum (10 microliters), 72 bacteria per monocyte cell, and 7.5 min opsonization and incubation time during continuous agitation at 37 degrees C. The CL was amplified by lucigenin. Preliminary experiments suggest that convalescent sera from patients with group B meningococcal disease induced increased CL responses compared to acute sera. Sera from volunteers immunized with an outer membrane complex vaccine from serogroup B, serotype 15:P1.16 or 2a:P1.2 meningococci also induced increased CL activity compared to preimmune sera. No such response was shown when a group B capsular polysaccharide vaccine was given. This response pattern was also demonstrated by a flow cytometric phagocytosis technique (FCM). Internalization of meningococci by monocytes was demonstrated by a FCM quenching technique and by transmission electron microscopy. CL and FCM represent rapid and reproducible methods for the measurement of opsonophagocytosis of meningococci by monocytes and may be performed with minute amounts of sera.
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Affiliation(s)
- H Sjursen
- Medical Department B, Tromsø Regional Hospital, Norway
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45
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Lehmann V, Benninghoff B, Dröge W. Selective induction of metabolic activation programs in peritoneal macrophages by lipopolysaccharide substructures. Infect Immun 1991; 59:2822-7. [PMID: 1906843 PMCID: PMC258092 DOI: 10.1128/iai.59.8.2822-2827.1991] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [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: 12/29/2022] Open
Abstract
The structural elements of Salmonella typhimurium lipopolysaccharides (LPS) that are able to stimulate peritoneal macrophages to produce increased amounts of prostaglandin E2, ornithine, and citrulline, agents known to modulate immune responses, are described. Two different incomplete lipid A structures which lack the carbohydrate portion, the nonhydroxylated fatty acids lauric acid and myristic acid (lipid A precursor IB), and additional palmitic acid (lipid A precursor IA) stimulated increased prostaglandin E2 synthesis but were unable to augment ornithine and citrulline production at concentrations of up to 0.5 microgram/ml. Acyl-deficient smooth LPS containing lipid A precursors IA and IB substituted by the complete carbohydrate region were able to augment prostaglandin E2 and ornithine production but failed, even at a high concentration (0.5 microgram/ml), to stimulate citrulline production. Moreover, Re glycolipids and smooth intact LPS containing the lipid A region with 3-acyloxyacyl residues possessed all of the structural requirements to induce increased prostaglandin E2, ornithine, and citrulline synthesis. Finally, all of the LPS structures, including lipid A precursors IA and IB stimulated, in combination with gamma interferon, production of citrulline with similar efficiencies. These results demonstrate that LPS contains various substructures including regions of the carbohydrate and lipid A structure that can deliver signals for the activation of peritoneal macrophages. Signals for partial activation of macrophages to produce prostaglandins and ornithine can be delivered by acyl-deficient LPS structures. In contrast, full activation of macrophages to produce citrulline requires an additional signal that is delivered by 3-acyloxyacyl residues of the lipid A region or gamma interferon.
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Affiliation(s)
- V Lehmann
- Deutsches Krebsforschungszentrum, Institut für Immunologie und Genetik, Heidelberg, Federal Republic of Germany
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46
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Abstract
Activated macrophages exert strong arginase (ASE) activity that converts L-arginine into ornithine, the key precursor for putrescine and polyamine biosynthesis. Macrophages were previously also shown to generate nitric oxide that is derived from the guanido group of arginine by the oxidative deiminase (OAD) reaction. In view of the physiological importance of ornithine and putrescine, we now investigated whether interferon-gamma (IFN-gamma), a principal stimulator of the OAD activity, may lead to the accumulation of the deiminated derivative citrulline at the expense of ornithine production, or whether the carbon backbone could be reutilized for the production of arginine and ornithine. Our experiments show that murine peritoneal macrophages treated with IFN-gamma in combination with tumor necrosis factor (TNF) or bacterial lipopolysaccharide (LPS) generate substantial amounts of citrulline as identified by amino acid analyzer and by thin-layer chromatography. Also, labeled citrulline is generated from [14C]L-arginine but not from [14C]L-ornithine. This suggests that macrophages have little or no capacity to convert ornithine into arginine. In the absence of IFN-gamma, TNF and LPS stimulate the conversion of arginine into ornithine but not citrulline. However, when TNF or LPS stimulated macrophages are simultaneously treated with IFN-gamma, ornithine production is relatively inhibited by the strong OAD reaction that competes with the ASE reaction for its substrate L-arginine. IFN-gamma thus down-regulates the availability of ornithine and putrescine. The lipid A precursor IA also induces, in conjunction with IFN-gamma, the production of citrulline but fails to stimulate the generation of ornithine.
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Affiliation(s)
- B Benninghoff
- Institute of Immunology and Genetics, German Cancer Research Center, Heidelberg
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47
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Kinzer D, Lehmann V. Extracellular ATP and adenosine modulate tumor necrosis factor-induced lysis of L929 cells in the presence of actinomycin D. The Journal of Immunology 1991. [DOI: 10.4049/jimmunol.146.8.2708] [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] [Indexed: 01/01/2023]
Abstract
Abstract
Extracellular ATP in concentrations of 0.5 to 2.5 mM modulates TNF-induced cytolysis of L929 cells in the presence of actinomycin D. When present throughout the entire assay period, it inhibits the TNF-induced cytolysis. ADP was less active whereas AMP and GTP were nonreactive. However, inhibition was also achieved by adenosine that was nearly as active as ATP. Yet, the inhibitory effect of ATP was not due to hydrolysis by ectoenzymes to form adenosine. Thus, the nonhydrolyzable ATP analogue adenyl(beta-gamma-methylendiphosphate) was equally effective in inhibiting TNF-induced cytolysis. Moreover, no conversion of ATP into adenosine was observed during the entire assay period. However, inhibition no longer occurred when the TNF and ATP containing medium was removed after 5 h and replaced by a fresh medium containing TNF and no ATP. We now observed substantial enhancement of the TNF-induced cytolysis by ATP. Finally, treatment with N6-(R-phenylisopropyl)adenosine or with aminophylline, which are thought to downregulate adenosine receptors and to prevent binding of ligands to adenosine receptors, respectively, abolishes adenosine and ATP-mediated inhibition. Again, substantial enhancement of the TNF-induced cytolysis was observed by ATP and only a minor effect by adenosine. The results together suggest that ATP interacts with purinoceptors on the plasma membrane and is capable to enhance and inhibit TNF-induced cytolysis under appropriate conditions. The outcome of the ATP-induced modulation may be influenced by adenosine receptors.
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Affiliation(s)
- D Kinzer
- Deutsches Krebsforschungszentrum, Institut für Immunologie und Genetik, Heidelberg, Germany
| | - V Lehmann
- Deutsches Krebsforschungszentrum, Institut für Immunologie und Genetik, Heidelberg, Germany
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48
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Kinzer D, Lehmann V. Extracellular ATP and adenosine modulate tumor necrosis factor-induced lysis of L929 cells in the presence of actinomycin D. J Immunol 1991; 146:2708-11. [PMID: 2016524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Extracellular ATP in concentrations of 0.5 to 2.5 mM modulates TNF-induced cytolysis of L929 cells in the presence of actinomycin D. When present throughout the entire assay period, it inhibits the TNF-induced cytolysis. ADP was less active whereas AMP and GTP were nonreactive. However, inhibition was also achieved by adenosine that was nearly as active as ATP. Yet, the inhibitory effect of ATP was not due to hydrolysis by ectoenzymes to form adenosine. Thus, the nonhydrolyzable ATP analogue adenyl(beta-gamma-methylendiphosphate) was equally effective in inhibiting TNF-induced cytolysis. Moreover, no conversion of ATP into adenosine was observed during the entire assay period. However, inhibition no longer occurred when the TNF and ATP containing medium was removed after 5 h and replaced by a fresh medium containing TNF and no ATP. We now observed substantial enhancement of the TNF-induced cytolysis by ATP. Finally, treatment with N6-(R-phenylisopropyl)adenosine or with aminophylline, which are thought to downregulate adenosine receptors and to prevent binding of ligands to adenosine receptors, respectively, abolishes adenosine and ATP-mediated inhibition. Again, substantial enhancement of the TNF-induced cytolysis was observed by ATP and only a minor effect by adenosine. The results together suggest that ATP interacts with purinoceptors on the plasma membrane and is capable to enhance and inhibit TNF-induced cytolysis under appropriate conditions. The outcome of the ATP-induced modulation may be influenced by adenosine receptors.
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Affiliation(s)
- D Kinzer
- Deutsches Krebsforschungszentrum, Institut für Immunologie und Genetik, Heidelberg, Germany
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49
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Flø RW, Naess A, Lund-Johansen F, Maehle BO, Sjursen H, Lehmann V, Solberg CO. Negative selection of human monocytes using magnetic particles covered by anti-lymphocyte antibodies. J Immunol Methods 1991; 137:89-94. [PMID: 2010620 DOI: 10.1016/0022-1759(91)90397-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [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: 12/29/2022]
Abstract
We have developed a standardized procedure for the isolation of monocytes from peripheral blood by negative selection using magnetic polymer particles coated with monoclonal antibodies against T and B lymphocytes. The average purity of the monocyte suspension was 85%, and monocyte recovery was 72% from Ficoll-Hypaque gradient separated mononuclear cells and 32% from whole blood. In a lucigenin enhanced chemiluminescence assay there was no significant difference between cells separated immunomagnetically and those separated on a gradient. Nor did electron microscopy show any significant difference in morphology between such monocytes. Negative selection using magnetic polymer particles is an efficient method for the separation of monocytes with intact morphology and function as measured by chemiluminescence.
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Affiliation(s)
- R W Flø
- Medical Department B, Haukeland Hospital, University of Bergen, Norway
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50
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Göckel D, Baum G, Fromme B, Lehmann V, Lohmann B, Raith W. Low-energy cathodoluminescence experiment with polarized electrons and a negative-electron-affinity GaAs target. Phys Rev B Condens Matter 1990; 42:7242-7244. [PMID: 9994854 DOI: 10.1103/physrevb.42.7242] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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