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Tewary G, Freyter B, Al-Razaq MA, Auerbach H, Laschke MW, Kübelbeck T, Kolb A, Mangelinck A, Mann C, Kramer D, Rübe CE. Immunomodulatory Effects of Histone Variant H2A.J in Ionizing Radiation Dermatitis. Int J Radiat Oncol Biol Phys 2024; 118:801-816. [PMID: 37758068 DOI: 10.1016/j.ijrobp.2023.09.022] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 08/01/2023] [Accepted: 09/14/2023] [Indexed: 10/03/2023]
Abstract
PURPOSE Histone variant H2A.J is associated with premature senescence after ionizing radiation (IR) and modulates senescence-associated secretory phenotype (SASP). Using constitutive H2A.J knock-out mice, the role of H2A.J was investigated in radiation dermatitis. METHODS AND MATERIALS H2A.J wild-type (WT) and knock-out (KO) mice were exposed to moderate or high IR doses (≤20 Gy, skinfold IR). Radiation-induced skin reactions were investigated up to 2 weeks post-IR at macroscopic and microscopic levels. H2A.J and other senescence markers, as well as DNA damage and proliferation markers, were studied by immunohistochemistry, immunofluorescence, and electron microscopy. After high-dose IR, protein-coding transcriptomes were analyzed by RNA sequencing, immune cell infiltration by flow cytometry, and gene expression by reverse transcription polymerase chain reaction in (non-) irradiated WT versus KO skin. RESULTS In WT skin, epidermal keratinocytes showed time- and dose-dependent H2A.J accumulation after IR exposure. Unexpectedly, stronger inflammatory reactions with increased epidermal thickness and progressive hair follicle loss were observed in irradiated KO versus WT skin. Clearly more radiation-induced senescence was observed in keratinocyte populations of KO skin after moderate and high doses, with hair follicle stem cells being particularly badly damaged, leading to follicle atrophy. After high-dose IR, transcriptomic analysis revealed enhanced senescence-associated signatures in irradiated KO skin, with intensified release of SASP factors. Flow cytometric analysis indicated increased immune cell infiltration in both WT and KO skin; however, specific chemokine-mediated signaling in irradiated KO skin led to more neutrophil recruitment, thereby aggravating radiation toxicities. Increased skin damage in irradiated KO skin led to hyperproliferation, abnormal differentiation, and cornification of keratinocytes, accompanied by increased upregulation of transcription-factor JunB. CONCLUSIONS Lack of radiation-induced H2A.J expression in keratinocytes is associated with increased senescence induction, modulation of SASP expression, and exacerbated inflammatory skin reactions. Hence, epigenetic H2A.J-mediated gene expression in response to IR regulates keratinocyte immune functions and plays an essential role in balancing the inflammatory response during radiation dermatitis.
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Affiliation(s)
- Gargi Tewary
- Department of Radiation Oncology, Saarland University Medical Center, Homburg/Saar, Germany
| | - Benjamin Freyter
- Department of Radiation Oncology, Saarland University Medical Center, Homburg/Saar, Germany
| | - Mutaz Abd Al-Razaq
- Department of Radiation Oncology, Saarland University Medical Center, Homburg/Saar, Germany
| | - Hendrik Auerbach
- Department of Radiation Oncology, Saarland University Medical Center, Homburg/Saar, Germany
| | - Matthias W Laschke
- Institute for Clinical and Experimental Surgery, Saarland University, Homburg/Saar, Germany
| | - Tanja Kübelbeck
- Department of Dermatology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Antonia Kolb
- Department of Dermatology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Adèle Mangelinck
- Institute for Integrative Biology of the Cell, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | - Carl Mann
- Institute for Integrative Biology of the Cell, Université Paris-Saclay, Gif-sur-Yvette Cedex, France
| | - Daniela Kramer
- Department of Dermatology, Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Claudia E Rübe
- Department of Radiation Oncology, Saarland University Medical Center, Homburg/Saar, Germany.
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Fischer B, Kübelbeck T, Kolb A, Ringen J, Waisman A, Wittmann M, Karbach S, Kölsch SM, Kramer D. IL-17A-driven psoriasis is critically dependent on IL-36 signaling. Front Immunol 2023; 14:1256133. [PMID: 38162658 PMCID: PMC10754973 DOI: 10.3389/fimmu.2023.1256133] [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] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 11/20/2023] [Indexed: 01/03/2024] Open
Abstract
Plaque psoriasis is an autoinflammatory and autoimmune skin disease, affecting 1-3% of the population worldwide. Previously, high levels of IL-36 family cytokines were found in psoriatic skin lesions, thereby contributing to keratinocyte hyperproliferation and infiltration of immune cells such as neutrophils. While treatment with anti-IL36 receptor (IL36R) antibodies was recently approved for generalized pustular psoriasis (GPP), it remains unclear, if targeting the IL36R might also inhibit plaque psoriasis. Here we show that antibody-mediated inhibition of IL36R is sufficient to suppress imiquimod-induced psoriasis-like skin inflammation and represses the disease's development in a model that depends on IL-17A overexpression in the skin. Importantly, treatment with anti-IL36R antibodies inhibited skin inflammation and attenuated psoriasis-associated, systemic inflammation. This is possibly due to a widespread effect of IL36R inhibition, which not only suppresses pro-inflammatory gene expression in keratinocytes, but also the activation of other immune cells such as T-cells or dendritic cells. In conclusion, we propose that inhibition of the IL-36 signaling pathway might constitute an attractive, alternative approach for treating IL-17A-driven psoriasis and psoriasis-linked comorbidities.
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Affiliation(s)
- Berenice Fischer
- Department of Dermatology, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany
| | - Tanja Kübelbeck
- Department of Dermatology, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany
| | - Antonia Kolb
- Department of Dermatology, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany
| | - Julia Ringen
- Center for Cardiology- Cardiology I, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany
- Center for Thrombosis and Hemostasis (CTH), University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany
| | - Ari Waisman
- Institute of Molecular Medicine, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany
- Research Center for Immunotherapy, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany
| | - Miriam Wittmann
- Department of Dermatology, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany
| | - Susanne Karbach
- Center for Cardiology- Cardiology I, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany
- Center for Thrombosis and Hemostasis (CTH), University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany
- German Center for Cardiovascular Research (DZHK) – Partner Site Rhine-Main, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Stephan Marcus Kölsch
- Boehringer Ingelheim Pharma GmbH & Co. KG, Medical Affairs, Ingelheim am Rhein, Germany
| | - Daniela Kramer
- Department of Dermatology, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany
- Research Center for Immunotherapy, University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany
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Vitali DG, Drwesh L, Cichocki BA, Kolb A, Rapaport D. The Biogenesis of Mitochondrial Outer Membrane Proteins Show Variable Dependence on Import Factors. iScience 2019; 23:100779. [PMID: 31945731 PMCID: PMC6965732 DOI: 10.1016/j.isci.2019.100779] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 11/12/2019] [Accepted: 12/12/2019] [Indexed: 12/14/2022] Open
Abstract
Biogenesis of mitochondrial outer membrane proteins involves their integration into the lipid bilayer. Among these proteins are those that form a single-span topology, but our understanding of their biogenesis is scarce. In this study, we found that the MIM complex is required for the membrane insertion of some single-span proteins. However, other such proteins integrate into the membrane in a MIM-independent manner. Moreover, the biogenesis of the studied proteins was dependent to a variable degree on the TOM receptors Tom20 and Tom70. We found that Atg32 C-terminal domain mediates dependency on Tom20, whereas the cytosolic domains of Atg32 and Gem1 facilitate MIM involvement. Collectively, our findings (1) enlarge the repertoire of MIM substrates to include also tail-anchored proteins, (2) provide new mechanistic insights to the functions of the MIM complex and TOM import receptors, and (3) demonstrate that the biogenesis of MOM single-span proteins shows variable dependence on import factors.
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Affiliation(s)
- Daniela G Vitali
- Interfaculty Institute of Biochemistry, University of Tübingen, Hoppe-Seyler-Str. 4, 72076 Tübingen, Germany
| | - Layla Drwesh
- Interfaculty Institute of Biochemistry, University of Tübingen, Hoppe-Seyler-Str. 4, 72076 Tübingen, Germany
| | - Bogdan A Cichocki
- Interfaculty Institute of Biochemistry, University of Tübingen, Hoppe-Seyler-Str. 4, 72076 Tübingen, Germany
| | - Antonia Kolb
- Interfaculty Institute of Biochemistry, University of Tübingen, Hoppe-Seyler-Str. 4, 72076 Tübingen, Germany
| | - Doron Rapaport
- Interfaculty Institute of Biochemistry, University of Tübingen, Hoppe-Seyler-Str. 4, 72076 Tübingen, Germany.
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Ma S, De Frenne P, Wasof S, Brunet J, Cousins SAO, Decocq G, Kolb A, Lemke I, Liira J, Naaf T, Orczewska A, Plue J, Wulf M, Verheyen K. Plant-soil feedbacks of forest understorey plants transplanted in nonlocal soils along a latitudinal gradient. Plant Biol (Stuttg) 2019; 21:677-687. [PMID: 30659728 DOI: 10.1111/plb.12960] [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] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Accepted: 01/14/2019] [Indexed: 06/09/2023]
Abstract
Climate change is driving movements of many plants beyond, as well as within, their current distributional ranges. Even migrant plants moving within their current range may experience different plant-soil feedbacks (PSF) because of divergent nonlocal biotic soil conditions. Yet, our understanding to what extent soil biotic conditions can affect the performance of within-range migrant plants is still very limited. We assessed the emergence and growth of migrant forest herbs (Milium effusum and Stachys sylvatica) using soils and seeds collected along a 1,700 km latitudinal gradient across Europe. Soil biota were manipulated through four soil treatments, i.e. unsterilized control soil (PSFUS ), sterilized soil (PSFS ), sterilized soil inoculated with unsterilized home soil (PSFS+HI ) and sterilized soil inoculated with unsterilized foreign soil (PSFS+FI , expected to occur when both plants and soil biota track climate change). Compared to PSFS , PSFUS had negative effects on the growth but not emergence of both species, while PSFS+FI only affected S. sylvatica across all seed provenances. When considering seed origin, seedling emergence and growth responses to nonlocal soils depended on soil biotic conditions. Specifically, the home-away distance effect on seedling emergence differed between the four treatments, and significant responses to chemistry either disappeared (M. effusum) or changed (S. sylvatica) from PSFUS to PSFS . Soil biota emerge as an important driver of the estimated plant migration success. Our results of the effects of soil microorganisms on plant establishment provide relevant information for predictions of the distribution and dynamics of plant species in a changing climate.
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Affiliation(s)
- S Ma
- Forest & Nature Lab, Ghent University, Melle-Gontrode, Belgium
| | - P De Frenne
- Forest & Nature Lab, Ghent University, Melle-Gontrode, Belgium
| | - S Wasof
- Forest & Nature Lab, Ghent University, Melle-Gontrode, Belgium
| | - J Brunet
- Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - S A O Cousins
- Department of Physical Geography, Stockholm University, Stockholm, Sweden
| | - G Decocq
- Plant Biodiversity Lab, University of Picardy Jules Verne, Amiens, France
| | - A Kolb
- Vegetation Ecology and Conservation Biology, Faculty of Biology/Chemistry (FB 02), University of Bremen, Bremen, Germany
| | - I Lemke
- Vegetation Ecology and Conservation Biology, Faculty of Biology/Chemistry (FB 02), University of Bremen, Bremen, Germany
| | - J Liira
- Department of Botany, University of Tartu, Tartu, Estonia
| | - T Naaf
- Leibniz Centre for Agricultural Landscape Research (ZALF), Müncheberg, Germany
| | - A Orczewska
- Department of Ecology, Faculty of Biology and Environmental Protection, University of Silesia, Katowice, Poland
| | - J Plue
- Department of Physical Geography, Stockholm University, Stockholm, Sweden
- School of Natural Sciences, Technology and Environmental Studies, Södertörn University, Stockholm, Sweden
| | - M Wulf
- Leibniz Centre for Agricultural Landscape Research (ZALF), Müncheberg, Germany
| | - K Verheyen
- Forest & Nature Lab, Ghent University, Melle-Gontrode, Belgium
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Abstract
The outcome of preclinical imaging studies are enhanced by simultaneous, high-resolution anatomical and molecular data, which advanced PET/MRI systems provide. Nevertheless, mapping of neuroreceptors and accurate quantification of PET tracer distribution in mouse brains is not trivial. The restricted spatial resolution and sensitivity in commercial animal PET systems limits the image quality and the quantification accuracy. We are currently developing a PET/MRI system dedicated for mouse brain studies. The PET system will offer system dimensions of approx. 30 mm in diameter and an axial length of more than 38 mm. This work discusses two system geometries including their associated block detectors. Both configurations were based on a dual layer offset structure with small crystals sizes, in the order of 1 × 1 × 4/6 mm3, to provide discrete depth of interaction information. The detector for configuration 'A' was based on a 4 × 4 silicon photomultiplier (SiPM) array attached to an optical diffusor, and a 12 × 12 as well as a 9 × 11 LSO crystal array, to achieve optimal system sensitivity. This configuration was evaluated by a double layer of 12 × 12 crystals. Configuration 'B' was composed of three 2 × 2 SiPM arrays equipped with a 1 mm diffusor to read out an LSO stack of 20 × 6 and 19 × 5 individual crystals. The average peak-to-valley ratio of the inner/outer layer was 3.5/3.6 for detector 'A', and 3.4/2.8 for detector 'B'. The average full width at half maximum (FWHM) energy resolution of the block detectors were 22.24% ± 3.36% for 'A' and 30.67% ± 5.37% for 'B'. The FWHM of the full block timing resolution of the inner/outer layer was 1.4 ns/1.2 ns for detector 'A' and 1.8 ns/1.4 ns for 'B'. The performance of the crystal position profile, the energy, and timing resolution indicate that configuration 'A' is more appropriate for a mouse brain PET/MRI system.
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Affiliation(s)
- C Parl
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University Tuebingen, Roentgenweg 13, 72076 Tuebingen, Germany
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Vitali DG, Käser S, Kolb A, Dimmer KS, Schneider A, Rapaport D. Independent evolution of functionally exchangeable mitochondrial outer membrane import complexes. eLife 2018; 7:34488. [PMID: 29923829 PMCID: PMC6010339 DOI: 10.7554/elife.34488] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 05/06/2018] [Indexed: 11/13/2022] Open
Abstract
Assembly and/or insertion of a subset of mitochondrial outer membrane (MOM) proteins, including subunits of the main MOM translocase, require the fungi-specific Mim1/Mim2 complex. So far it was unclear which proteins accomplish this task in other eukaryotes. Here, we show by reciprocal complementation that the MOM protein pATOM36 of trypanosomes is a functional analogue of yeast Mim1/Mim2 complex, even though these proteins show neither sequence nor topological similarity. Expression of pATOM36 rescues almost all growth, mitochondrial biogenesis, and morphology defects in yeast cells lacking Mim1 and/or Mim2. Conversely, co-expression of Mim1 and Mim2 restores the assembly and/or insertion defects of MOM proteins in trypanosomes ablated for pATOM36. Mim1/Mim2 and pATOM36 form native-like complexes when heterologously expressed, indicating that additional proteins are not part of these structures. Our findings indicate that Mim1/Mim2 and pATOM36 are the products of convergent evolution and arose only after the ancestors of fungi and trypanosomatids diverged.
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Affiliation(s)
- Daniela G Vitali
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Sandro Käser
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Antonia Kolb
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Kai S Dimmer
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Andre Schneider
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Doron Rapaport
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
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7
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De Frenne P, Blondeel H, Brunet J, Carón MM, Chabrerie O, Cougnon M, Cousins SAO, Decocq G, Diekmann M, Graae BJ, Hanley ME, Heinken T, Hermy M, Kolb A, Lenoir J, Liira J, Orczewska A, Shevtsova A, Vanneste T, Verheyen K. Atmospheric nitrogen deposition on petals enhances seed quality of the forest herb Anemone nemorosa. Plant Biol (Stuttg) 2018; 20:619-626. [PMID: 29323793 DOI: 10.1111/plb.12688] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 01/06/2018] [Indexed: 05/18/2023]
Abstract
Elevated atmospheric input of nitrogen (N) is currently affecting plant biodiversity and ecosystem functioning. The growth and survival of numerous plant species is known to respond strongly to N fertilisation. Yet, few studies have assessed the effects of N deposition on seed quality and reproductive performance, which is an important life-history stage of plants. Here we address this knowledge gap by assessing the effects of atmospheric N deposition on seed quality of the ancient forest herb Anemone nemorosa using two complementary approaches. By taking advantage of the wide spatiotemporal variation in N deposition rates in pan-European temperate and boreal forests over 2 years, we detected positive effects of N deposition on the N concentration (percentage N per unit seed mass, increased from 2.8% to 4.1%) and N content (total N mass per seed more than doubled) of A. nemorosa seeds. In a complementary experiment, we applied ammonium nitrate to aboveground plant tissues and the soil surface to determine whether dissolved N sources in precipitation could be incorporated into seeds. Although the addition of N to leaves and the soil surface had no effect, a concentrated N solution applied to petals during anthesis resulted in increased seed mass, seed N concentration and N content. Our results demonstrate that N deposition on the petals enhances bioaccumulation of N in the seeds of A. nemorosa. Enhanced atmospheric inputs of N can thus not only affect growth and population dynamics via root or canopy uptake, but can also influence seed quality and reproduction via intake through the inflorescences.
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Affiliation(s)
- P De Frenne
- Department of Plant & Crops, Ghent University, Melle, Belgium
- Forest & Nature Lab, Ghent University, Melle-Gontrode, Belgium
| | - H Blondeel
- Forest & Nature Lab, Ghent University, Melle-Gontrode, Belgium
| | - J Brunet
- Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - M M Carón
- Forest & Nature Lab, Ghent University, Melle-Gontrode, Belgium
- Laboratorio de Investigaciones Botánicas (LABIBO), Facultad de Ciencias Naturales, Universidad Nacional de Salta-CONICET, Salta, Argentina
| | - O Chabrerie
- Unité de recherche "Ecologie et Dynamique des Systèmes Anthropisés" (EDYSAN, FRE3498 CNRS-UPJV), Université de Picardie Jules Verne, Amiens, France
| | - M Cougnon
- Department of Plant & Crops, Ghent University, Melle, Belgium
| | - S A O Cousins
- Biogeography and Geomatics, Department of Physical Geography, Stockholm University, Stockholm, Sweden
| | - G Decocq
- Unité de recherche "Ecologie et Dynamique des Systèmes Anthropisés" (EDYSAN, FRE3498 CNRS-UPJV), Université de Picardie Jules Verne, Amiens, France
| | - M Diekmann
- Vegetation Ecology and Conservation Biology, Institute of Ecology, University of Bremen, Bremen, Germany
| | - B J Graae
- Department of Biology, Norwegian University of Science and Technology, Trondheim, Norway
| | - M E Hanley
- School of Biological Sciences, University of Plymouth, Plymouth, UK
| | - T Heinken
- General Botany, University of Potsdam, Potsdam, Germany
| | - M Hermy
- Division Forest, Nature and Landscape, KULeuven, Leuven, Belgium
| | - A Kolb
- Vegetation Ecology and Conservation Biology, Institute of Ecology, University of Bremen, Bremen, Germany
| | - J Lenoir
- Unité de recherche "Ecologie et Dynamique des Systèmes Anthropisés" (EDYSAN, FRE3498 CNRS-UPJV), Université de Picardie Jules Verne, Amiens, France
| | - J Liira
- Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
| | - A Orczewska
- Department of Ecology, Faculty of Biology and Environmental Protection, University of Silesia, Katowice, Poland
| | - A Shevtsova
- Department of Medical Biochemistry and Biophysics, Umeå University, Umeå, Sweden
| | - T Vanneste
- Department of Plant & Crops, Ghent University, Melle, Belgium
- Forest & Nature Lab, Ghent University, Melle-Gontrode, Belgium
| | - K Verheyen
- Forest & Nature Lab, Ghent University, Melle-Gontrode, Belgium
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Abstract
This study depicts the evaluation of a SiPM detector with depth of interaction (DOI) capability via a dual-sided readout that is suitable for high-resolution positron emission tomography and magnetic resonance (PET/MR) imaging. Two different 12 × 12 pixelated LSO scintillator arrays with a crystal pitch of 1.60 mm are examined. One array is 20 mm-long with a crystal separation by the specular reflector Vikuiti enhanced specular reflector (ESR), and the other one is 18 mm-long and separated by the diffuse reflector Lumirror E60 (E60). An improvement in energy resolution from 22.6% to 15.5% for the scintillator array with the E60 reflector is achieved by taking a nonlinear light collection correction into account. The results are FWHM energy resolutions of 14.0% and 15.5%, average FWHM DOI resolutions of 2.96 mm and 1.83 mm, and FWHM coincidence resolving times of 1.09 ns and 1.48 ns for the scintillator array with the ESR and that with the E60 reflector, respectively. The measured DOI signal ratios need to be assigned to an interaction depth inside the scintillator crystal. A linear and a nonlinear method, using the intrinsic scintillator radiation from lutetium, are implemented for an easy to apply calibration and are compared to the conventional method, which exploits a setup with an externally collimated radiation beam. The deviation between the DOI functions of the linear or nonlinear method and the conventional method is determined. The resulting average of differences in DOI positions is 0.67 mm and 0.45 mm for the nonlinear calibration method for the scintillator array with the ESR and with the E60 reflector, respectively; Whereas the linear calibration method results in 0.51 mm and 0.32 mm for the scintillator array with the ESR and the E60 reflector, respectively; and is, due to its simplicity, also applicable in assembled detector systems.
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Affiliation(s)
- F P Schmidt
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tübingen, Tübingen, Germany
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Ziegenhain U, Peter A, von Wietersheim H, Vicari A, Kolb A, Schulze U, Buchheim A. Unverarbeitete Verlusterfahrungen und Angststörungen. ACTA ACUST UNITED AC 2018. [DOI: 10.1055/s-0038-1626971] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
ZusammenfassungZielsetzung der vorliegenden Studie war es, erstmals im deutschen Sprachraum die generationsübergreifenden Zusammenhänge zwischen Angststörungen bei Müttern und möglichen Verhaltensauffälligkeiten ihrer Kinder im Kindergartenalter im Kontext der Weitergabe von Bindungsmustern zu untersuchen. Um bindungsspezifische Risikofaktoren zu identifizieren, wurden sowohl die Mütter als auch deren Kinder mit Methoden der Bindungsforschung untersucht. Entsprechend unserer Hypothese wurde bei den Müttern mit einer manifesten Angststörung ein hoher Anteil an unsicherer Bindungsrepräsentation und insbesondere unverarbeiteter Trauer klassifiziert. Die Kinder dieser Mütter zeigten ebenso zu einem hohen Prozentsatz unsicherer Bindungsmuster, jedoch nicht wie erwartet keinen erhöhten Anteil an desorganisierter Bindung. Die kinder- und jugendpsychiatrische Untersuchung führte bei den meisten Kindern zum Befund einer nachweisbar erhöhten psychosozialen Belastung und Beeinträchtigung des psychosozialen Funktionsniveaus, wenn auch nicht im psychiatrisch auffälligen Bereich. Hier liegen die Chancen für eine interdisziplinäre Zusammenarbeit mit rechtzeitigen, auch präventiven Angeboten und Hilfen, wie sie in der klinischen Versorgungslandschaft derzeit noch nicht systematisch vorgehalten werden.
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Vitali DG, Sinzel M, Bulthuis EP, Kolb A, Zabel S, Mehlhorn DG, Costa BF, Farkas Á, Clancy A, Schuldiner M, Grefen C, Schwappach B, Borgese N, Rapaport D. The GET pathway can increase the risk of mitochondrial outer membrane proteins to be mistargeted to the ER. J Cell Sci 2018; 131:jcs.211110. [DOI: 10.1242/jcs.211110] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 04/10/2018] [Indexed: 01/23/2023] Open
Abstract
Tail-anchored (TA) proteins are anchored to their corresponding membrane via a single transmembrane segment (TMS) at their C-terminus. In yeast, the targeting of TA proteins to the endoplasmic reticulum (ER) can be mediated by the guided entry of TA proteins (GET) pathway, whereas it is not yet clear how mitochondrial TA proteins are targeted to their destination. It is widely observed that some mitochondrial outer membrane (OM) proteins are mistargeted to the ER when overexpressed or when their targeting signal is masked. However, the mechanism of this erroneous sorting is currently unknown. In this study, we demonstrate the involvement of the GET machinery in mistargeting of non-optimal mitochondrial OM proteins to the ER. These findings suggest that the GET machinery can, in principle, recognize and guide mitochondrial and non-canonical TA proteins. Hence, under normal conditions, an active mitochondrial targeting pathway must exist that dominates the kinetic competition against other pathways.
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Affiliation(s)
- Daniela G. Vitali
- Interfaculty Institute of Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Monika Sinzel
- Interfaculty Institute of Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Elianne P. Bulthuis
- Interfaculty Institute of Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Antonia Kolb
- Interfaculty Institute of Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Susanne Zabel
- Interfaculty Institute of Biochemistry, University of Tübingen, 72076 Tübingen, Germany
| | - Dietmar G. Mehlhorn
- Centre for Plant Molecular Biology, Developmental Genetics, University of Tübingen, Tübingen, Germany
| | | | - Ákos Farkas
- Department of Molecular Biology, Universitätsmedizin Göttingen, Göttingen 37073, Germany
| | - Anne Clancy
- Department of Molecular Biology, Universitätsmedizin Göttingen, Göttingen 37073, Germany
| | - Maya Schuldiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Christopher Grefen
- Centre for Plant Molecular Biology, Developmental Genetics, University of Tübingen, Tübingen, Germany
| | - Blanche Schwappach
- Department of Molecular Biology, Universitätsmedizin Göttingen, Göttingen 37073, Germany
| | - Nica Borgese
- Consiglio Nazionale delle Ricerche Institute of Neuroscience, Milan, Italy
| | - Doron Rapaport
- Interfaculty Institute of Biochemistry, University of Tübingen, 72076 Tübingen, Germany
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11
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Affiliation(s)
- A Kolb
- Department of Renal Medicine, Royal Infirmary of Edinburgh, UK
| | - P Gibson
- Department of Renal Medicine, Royal Infirmary of Edinburgh, UK
| | - E D O'Sullivan
- Department of Renal Medicine, Royal Infirmary of Edinburgh, UK
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Parl C, Kolb A, Schmid AM, Wehrl HF, Disselhorst JA, Soubiran PD, Stricker-Shaver D, Pichler BJ. A novel optically transparent RF shielding for fully integrated PET/MRI systems. ACTA ACUST UNITED AC 2017; 62:7357-7378. [DOI: 10.1088/1361-6560/aa8384] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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13
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Kolb A, Windhager R, Chiari C. Kongenitale Hüftdysplasie, Screening und Therapie. Monatsschr Kinderheilkd 2016. [DOI: 10.1007/s00112-016-0064-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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14
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Abstract
Congenital hip dysplasia and hip dislocation are relatively common pathological conditions of the musculoskeletal system in infants. An early and certain diagnosis can now be achieved by sonographic hip screening within the framework of screening examination programs. This early diagnostic procedure in infants is essential particularly for a conservative treatment strategy. Therefore, apart from possessing in-depth knowledge, training of the examiner in specialist courses is of central importance. This article presents an overview of the entity of congenital hip dysplasia and hip dislocation, the diagnostics and treatment with special emphasis on recent developments.
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Affiliation(s)
- A Kolb
- Univ. Klinik für Orthopädie, Medizinische Universität Wien, Wien, Österreich
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15
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Kolb A, Parl C, Mantlik F, Liu CC, Lorenz E, Renker D, Pichler BJ. Development of a novel depth of interaction PET detector using highly multiplexed G-APD cross-strip encoding. Med Phys 2015; 41:081916. [PMID: 25086547 DOI: 10.1118/1.4890609] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE The aim of this study was to develop a prototype PET detector module for a combined small animal positron emission tomography and magnetic resonance imaging (PET/MRI) system. The most important factor for small animal imaging applications is the detection sensitivity of the PET camera, which can be optimized by utilizing longer scintillation crystals. At the same time, small animal PET systems must yield a high spatial resolution. The measured object is very close to the PET detector because the bore diameter of a high field animal MR scanner is limited. When used in combination with long scintillation crystals, these small-bore PET systems generate parallax errors that ultimately lead to a decreased spatial resolution. Thus, we developed a depth of interaction (DoI) encoding PET detector module that has a uniform spatial resolution across the whole field of view (FOV), high detection sensitivity, compactness, and insensitivity to magnetic fields. METHODS The approach was based on Geiger mode avalanche photodiode (G-APD) detectors with cross-strip encoding. The number of readout channels was reduced by a factor of 36 for the chosen block elements. Two 12 × 2 G-APD strip arrays (25 μm cells) were placed perpendicular on each face of a 12 × 12 lutetium oxyorthosilicate crystal block with a crystal size of 1.55 × 1.55 × 20 mm. The strip arrays were multiplexed into two channels and used to calculate the x, y coordinates for each array and the deposited energy. The DoI was measured in step sizes of 1.8 mm by a collimated (18)F source. The coincident resolved time (CRT) was analyzed at all DoI positions by acquiring the waveform for each event and applying a digital leading edge discriminator. RESULTS All 144 crystals were well resolved in the crystal flood map. The average full width half maximum (FWHM) energy resolution of the detector was 12.8% ± 1.5% with a FWHM CRT of 1.14 ± 0.02 ns. The average FWHM DoI resolution over 12 crystals was 2.90 ± 0.15 mm. CONCLUSIONS The novel DoI PET detector, which is based on strip G-APD arrays, yielded a DoI resolution of 2.9 mm and excellent timing and energy resolution. Its high multiplexing factor reduces the number of electronic channels. Thus, this cross-strip approach enables low-cost, high-performance PET detectors for dedicated small animal PET and PET/MRI and potentially clinical PET/MRI systems.
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Affiliation(s)
- A Kolb
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tübingen, Germany
| | - C Parl
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tübingen, Germany
| | - F Mantlik
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tübingen, Germany and Department of Empirical Inference, Max Planck Institute for Intelligent Systems, 72076 Tübingen, Germany
| | - C C Liu
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tübingen, Germany
| | - E Lorenz
- Max Planck Institute for Physics, Föhringer Ring 6, 80805 München, Germany
| | - D Renker
- Department of Physics, Technische Universität München, 85748 Garching, Germany
| | - B J Pichler
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University, 72076 Tübingen, Germany
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16
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Carón MM, De Frenne P, Brunet J, Chabrerie O, Cousins SAO, De Backer L, Decocq G, Diekmann M, Heinken T, Kolb A, Naaf T, Plue J, Selvi F, Strimbeck GR, Wulf M, Verheyen K. Interacting effects of warming and drought on regeneration and early growth of Acer pseudoplatanus and A. platanoides. Plant Biol (Stuttg) 2015; 17:52-62. [PMID: 24750437 DOI: 10.1111/plb.12177] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 02/03/2014] [Indexed: 06/03/2023]
Abstract
Climate change is acting on several aspects of plant life cycles, including the sexual reproductive stage, which is considered amongst the most sensitive life-cycle phases. In temperate forests, it is expected that climate change will lead to a compositional change in community structure due to changes in the dominance of currently more abundant forest tree species. Increasing our understanding of the effects of climate change on currently secondary tree species recruitment is therefore important to better understand and forecast population and community dynamics in forests. Here, we analyse the interactive effects of rising temperatures and soil moisture reduction on germination, seedling survival and early growth of two important secondary European tree species, Acer pseudoplatanus and A. platanoides. Additionally, we analyse the effect of the temperature experienced by the mother tree during seed production by collecting seeds of both species along a 2200-km long latitudinal gradient. For most of the responses, A. platanoides showed higher sensitivity to the treatments applied, and especially to its joint manipulation, which for some variables resulted in additive effects while for others only partial compensation. In both species, germination and survival decreased with rising temperatures and/or soil moisture reduction while early growth decreased with declining soil moisture content. We conclude that although A. platanoides germination and survival were more affected after the applied treatments, its initial higher germination and larger seedlings might allow this species to be relatively more successful than A. pseudoplatanus in the face of climate change.
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Affiliation(s)
- M M Carón
- Forest & Nature Lab, Ghent University, Gontrode-Melle, Belgium
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Smith M, Kang M, Reynolds P, Lock R, Carol H, Gorlick R, Kolb A, Maris J, Keir S, Wu J, Kurmasheva R, Houghton P. 410 Pediatric Preclinical Testing Program (PPTP) Evaluation of the p53-MDM2 Antagonist MK-8242. Eur J Cancer 2014. [DOI: 10.1016/s0959-8049(14)70536-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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18
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Houghton P, Lock R, Carol H, Gorlick R, Kolb A, Maris J, Keir S, Wu J, Kang M, Reynolds P, Kurmasheva R, Smith M. 412 The Pediatric Preclinical Testing Program (PPTP): Analysis of the first 10 years in vivo testing. Eur J Cancer 2014. [DOI: 10.1016/s0959-8049(14)70538-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Kolb A, Watts C, Piccirillo S. DD-06 * POTENTIATING THE THERAPEUTIC EFFICIENCY OF THE ALKYLATING CHEMOTHERAPY TEMOZOLOMIDE IN PATIENTS WITH GLIOBLASTOMA. Neuro Oncol 2014. [DOI: 10.1093/neuonc/nou246.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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20
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Kolb A, Piccirillo S, Watts C. P49 * SENSITIZING GLIOBLASTOMA CELLS TO THERAPY BY TARGETING THE L-GLUTAMATE/L-CYSTINE ANTIPORTER SYSTEM XC-. Neuro Oncol 2014. [DOI: 10.1093/neuonc/nou249.37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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21
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Kolb A, Trecharichi A, Piccirillo S, Watts C, Price S. OP08 * CHARACTERISATION OF RESIDUAL CELLS IN GLIOBLASTOMA MULTIFORME. Neuro Oncol 2014. [DOI: 10.1093/neuonc/nou251.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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22
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Lass R, Grübl A, Kolb A, Domayer S, Csuk C, Kubista B, Giurea A, Windhager R. Primary cementless total hip arthroplasty with second-generation metal-on-metal bearings: a concise follow-up, at a minimum of seventeen years, of a previous report. J Bone Joint Surg Am 2014; 96:e37. [PMID: 24599209 DOI: 10.2106/jbjs.m.00748] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Second-generation, metal-on-metal bearings were introduced in 1988, to reduce wear and avoid polyethylene particle-induced osteolysis from total hip arthroplasty. In 2007, we reported the long-term results of ninety-eight patients (105 hips) who underwent primary cementless total hip arthroplasty involving the use of a prosthesis with a high-carbide-concentration, metal-on-metal articulating surface between November 1992 and May 1994. The present study gives an update on this patient cohort. METHODS At a minimum of seventeen years postoperatively, forty-nine patients (fifty-two hips) were available for follow-up examination. We retrospectively evaluated clinical and radiographic results as well as serum metal concentration. The mean patient age at the time of the index arthroplasty was fifty-six years. RESULTS Three cups (6% of the hips) and one stem (2% of the hips) were revised because of aseptic loosening of the implants combined with focal osteolysis. At the time of the latest follow-up evaluation, the mean Harris hip score was 88.8 points, and the mean University of California Los Angeles (UCLA) activity score was 6.7 points. The cumulative rate of implant survival, with aseptic failure as the end point, was 93.0% at 18.8 years. The median serum cobalt concentration in patients whose hip implant was the only source of cobalt was 0.70 μg/L (range, 0.4 to 5.1 μg/L), showing no increase in the value as noted at a minimum of ten years of follow-up. CONCLUSIONS The clinical and radiographic results of our study, which, to our knowledge, represent the longest duration of follow-up for a series of cementless total hip arthroplasties with use of a 28-mm metal-on-metal bearing, continue to be comparable with the results observed for other hard-on-hard bearings.
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Affiliation(s)
- R Lass
- Department of Orthopedics, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria. E-mail address for R. Lass:
| | - A Grübl
- Sanatorium Hera, Löblichgasse 14, A-1090 Vienna, Austria
| | - A Kolb
- Department of Orthopedics, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria. E-mail address for R. Lass:
| | - S Domayer
- Department of Orthopedics, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria. E-mail address for R. Lass:
| | - C Csuk
- Department of Orthopedics, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria. E-mail address for R. Lass:
| | - B Kubista
- Department of Orthopedics, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria. E-mail address for R. Lass:
| | - A Giurea
- Department of Orthopedics, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria. E-mail address for R. Lass:
| | - R Windhager
- Department of Orthopedics, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna, Austria. E-mail address for R. Lass:
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Abstract
Both differences in local plant density and phenotypic traits may affect pollination and plant reproduction, but little is known about how density affects trait-fitness relationships via changes in pollinator activity. In this study we examined how plant density and traits interact to determine pollinator behaviour and female reproductive success in the self-incompatible, perennial herb Phyteuma spicatum. Specifically, we hypothesised that limited pollination service in more isolated plants would lead to increased selection for traits that attract pollinators. We conducted pollinator observations and assessed trait-fitness relationships in a natural population, whose individuals were surrounded by a variable number of inflorescences. Both local plant density and plant phenotypic traits affected pollinator foraging behaviour. At low densities, pollinator visitation rates were low, but increased with increasing inflorescence size, while this relationship disappeared at high densities, where visitation rates were higher. Plant fitness, in terms of seed production per plant and per capsule, was related to both floral display size and flowering time. Seed production increased with increasing inflorescence size and was highest at peak flowering. However, trait-fitness relationships were not density-dependent, and differences in seed production did not appear to be related to differences in pollination. The reasons for this remain unclear, and additional studies are needed to fully understand and explain the observed patterns.
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Affiliation(s)
- A Weber
- Vegetation Ecology and Conservation Biology, Institute of Ecology, University of Bremen, Leobener Strasse, Bremen, Germany.
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Schwenzer NF, Stegger L, Bisdas S, Schraml C, Kolb A, Boss A, Müller M, Reimold M, Ernemann U, Claussen CD, Pfannenberg C, Schmidt H. Simultaneous PET/MR imaging in a human brain PET/MR system in 50 patients--current state of image quality. Eur J Radiol 2012; 81:3472-8. [PMID: 22260898 DOI: 10.1016/j.ejrad.2011.12.027] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 12/14/2011] [Accepted: 12/15/2011] [Indexed: 11/26/2022]
Abstract
OBJECTIVES The present work illustrates the current state of image quality and diagnostic accuracy in a new hybrid BrainPET/MR. MATERIALS AND METHODS 50 patients with intracranial masses, head and upper neck tumors or neurodegenerative diseases were examined with a hybrid BrainPET/MR consisting of a conventional 3T MR system and an MR-compatible PET insert. Directly before PET/MR, all patients underwent a PET/CT examination with either [18F]-FDG, [11C]-methionine or [68Ga]-DOTATOC. In addition to anatomical MR scans, functional sequences were performed including diffusion tensor imaging (DTI), arterial spin labeling (ASL) and proton-spectroscopy. Image quality score of MR imaging was evaluated using a 4-point-scale. PET data quality was assessed by evaluating FDG-uptake and tumor delineation with [11C]-methionine and [68Ga]-DOTATOC. FDG uptake quantification accuracy was evaluated by means of ROI analysis (right and left frontal and temporo-occipital lobes). The asymmetry indices and ratios between frontal and occipital ROIs were compared. RESULTS In 45/50 patients, PET/MR examination was successful. Visual analysis revealed a diagnostic image quality of anatomical MR imaging (mean quality score T2 FSE: 1.27±0.54; FLAIR: 1.38±0.61). ASL and proton-spectroscopy was possible in all cases. In DTI, dental artifacts lead to one non-diagnostic dataset (mean quality score DTI: 1.32±0.69; ASL: 1.10±0.31). PET datasets of PET/MR and PET/CT offered comparable tumor delineation with [11C]-methionine; additional lesions were found in 2/8 [(68)Ga]-DOTATOC-PET in the PET/MR. Mean asymmetry index revealed a high accordance between PET/MR and PET/CT (1.5±2.2% vs. 0.9±3.6%; mean ratio (frontal/parieto-occipital) 0.93±0.08 vs. 0.96±0.05), respectively. CONCLUSIONS The hybrid BrainPET/MR allows for molecular, anatomical and functional imaging with uncompromised MR image quality and a high accordance of PET results between PET/MR and PET/CT. These results justify the application of this technique in further clinical studies and may contribute to the transfer into whole-body PET/MR systems.
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Affiliation(s)
- N F Schwenzer
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls University Tübingen, Tübingen, Germany.
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25
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De Frenne P, Kolb A, Graae BJ, Decocq G, Baltora S, De Schrijver A, Brunet J, Chabrerie O, Cousins SAO, Dhondt R, Diekmann M, Gruwez R, Heinken T, Hermy M, Liira J, Saguez R, Shevtsova A, Baskin CC, Verheyen K. A latitudinal gradient in seed nutrients of the forest herb Anemone nemorosa. Plant Biol (Stuttg) 2011; 13:493-501. [PMID: 21489100 DOI: 10.1111/j.1438-8677.2010.00404.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The nutrient concentration in seeds determines many aspects of potential success of the sexual reproductive phase of plants, including the seed predation probability, efficiency of seed dispersal and seedling performance. Despite considerable research interest in latitudinal gradients of foliar nutrients, a similar gradient for seeds remains unexplored. We investigated a potential latitudinal gradient in seed nutrient concentrations within the widespread European understorey forest herb Anemone nemorosa L. We sampled seeds of A. nemorosa in 15 populations along a 1900-km long latitudinal gradient at three to seven seed collection dates post-anthesis and investigated the relative effects of growing degree-hours >5 °C, soil characteristics and latitude on seed nutrient concentrations. Seed nitrogen, nitrogen:phosphorus ratio and calcium concentration decreased towards northern latitudes, while carbon:nitrogen ratios increased. When taking differences in growing degree-hours and measured soil characteristics into account and only considering the most mature seeds, the latitudinal decline remained particularly significant for seed nitrogen concentration. We argue that the decline in seed nitrogen concentration can be attributed to northward decreasing seed provisioning due to lower soil nitrogen availability or greater investment in clonal reproduction. This pattern may have large implications for the reproductive performance of this forest herb as the degree of seed provisioning ultimately co-determines seedling survival and reproductive success.
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Affiliation(s)
- P De Frenne
- Laboratory of Forestry, Ghent University, Melle-Gontrode, Belgium.
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Schwenzer NF, Kolb A, Reimold M, Boss A, Stegger L, Bisdas S, Pichler B, Pfannenberg C, Claussen CD. Morphologische, funktionelle und metabolische Bildgebung an einem 3T BrainPET/MRT- ein Statusbericht. ROFO-FORTSCHR RONTG 2011. [DOI: 10.1055/s-0031-1279368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Abstract
The processing power of parallel coprocessors like the Graphics Processing Unit (GPU) is dramatically increasing. However, until now only a few approaches have been presented to utilize this kind of hardware for mesh clustering purposes. In this paper, we introduce a Multilevel clustering technique designed as a parallel algorithm and solely implemented on the GPU. Our formulation uses the spatial coherence present in the cluster optimization and hierarchical cluster merging to significantly reduce the number of comparisons in both parts. Our approach provides a fast, high-quality, and complete clustering analysis. Furthermore, based on the original concept, we present a generalization of the method to data clustering. All advantages of the mesh-based techniques smoothly carry over to the generalized clustering approach. Additionally, this approach solves the problem of the missing topological information inherent to general data clustering and leads to a Local Neighbors k-means algorithm. We evaluate both techniques by applying them to Centroidal Voronoi Diagram (CVD)-based clustering. Compared to classical approaches, our techniques generate results with at least the same clustering quality. Our technique proves to scale very well, currently being limited only by the available amount of graphics memory.
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Haeusler G, Freilinger M, Dominkus M, Egerbacher M, Amann G, Kolb A, Schlegel W, Raimann A, Staudenherz A. Tumor-induced hypophosphatemic rickets in an adolescent boy--clinical presentation, diagnosis, and histological findings in growth plate and muscle tissue. J Clin Endocrinol Metab 2010; 95:4511-7. [PMID: 20660029 DOI: 10.1210/jc.2010-0543] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT The mechanism behind disabling muscle weakness in tumor-induced hypophosphatemic rickets is obscure. Histological investigation of growth plate tissue of patients with tumor-induced osteomalacia has so far not been reported. PATIENT A mesenchymal tumor was detected in the left distal fibula by (68)Ga-DOTATOC in a 17-yr-old boy with adolescent onset of severe hypophosphatemic rickets. Disabling muscle weakness improved within days after surgery, and normal mobility was restored within months. METHODS AND RESULTS The resected tissue included part of the growth plate allowing immunohistochemical investigation. Positive staining of FGF23 was found in the tumor cells and in hypertrophic chondrocytes, osteoblasts, and osteoclasts of the adjacent growth plate. This distribution matched that found in growth plate tissue of a healthy control. We found positive staining for the somatostatin receptor not only in the tumor but also within the growth plate and adjacent bony tissue in the patient and the healthy control. Muscle tissue provided evidence for a partial defect in respiratory chain complexes I-IV. Biochemical markers were nearly or completely restored to normal 12 months after surgery. CONCLUSIONS Hypertrophic growth plate chondrocytes are a target or source of FGF23 in tumor-induced osteomalacia. Low serum phosphate, FGF23, or other factors produced by the tumor may interfere with mitochondrial function.
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Affiliation(s)
- G Haeusler
- Pediatric Department, Medical University of Vienna, Vienna, Austria.
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Sauter AW, Boss A, Kolb A, Mantlik M, Bethge W, Kanz L, Pfannenberg C, Stegger L, Pichler B, Claussen C, Horger M. Erste Erfahrungen bei der Beurteilung hämato-onkologischer Krankheitsmanifestationen an den Extremitäten mit einem PET/MRT-Hybridsystem. ROFO-FORTSCHR RONTG 2010. [DOI: 10.1055/s-0030-1253047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Boss A, Bisdas S, Kolb A, Hofmann M, Nägele T, Ernemann U, Schlemmer HP, Claussen C, Reimold M, Pfannenberg C, Pichler B, Stegger L. Hybride PET/MRT-Bildgebung von intracraniellen Tumoren: Erste Erfahrungen und Vergleich zum PET/CT. ROFO-FORTSCHR RONTG 2010. [DOI: 10.1055/s-0030-1252583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Boss A, Kolb A, Hofmann M, Bisdas S, Nägele T, Ernemann U, Stegger L, Schlemmer HP, Claussen C, Pfannenberg C, Reimold M, Pichler B, Klose U. Diffusion-Tensor-Bildgebung und Traktographie an einem humanen PET/MRT-Hybridsystem. ROFO-FORTSCHR RONTG 2010. [DOI: 10.1055/s-0030-1252713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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32
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Toegel S, Pabst M, Wu SQ, Grass J, Goldring MB, Chiari C, Kolb A, Altmann F, Viernstein H, Unger FM. Phenotype-related differential alpha-2,6- or alpha-2,3-sialylation of glycoprotein N-glycans in human chondrocytes. Osteoarthritis Cartilage 2010; 18:240-8. [PMID: 19800998 PMCID: PMC2818349 DOI: 10.1016/j.joca.2009.09.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2009] [Revised: 08/18/2009] [Accepted: 09/09/2009] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Sialic acids frequently occur at the terminal positions of glycoprotein N-glycans present at chondrocyte surfaces or in the cartilage matrix. Sialic acids are transferred to glycoproteins in either alpha-2,3 or alpha-2,6 linkage by specific sialyltransferases (SiaTs) and can potentially affect cell functions and cell-matrix interactions. The present study aimed to assess the relationship between the expression of the human chondrocyte phenotype and the sialylation of chondrocyte glycoprotein N-glycans. METHODS The transcription of 5 SiaT was quantified using real-time Reverse transcription polymerase chain reaction (RT-PCR) assays. N-glycan analysis was performed using LC-ESI-MS. Primary human chondrocytes were cultured in monolayer or alginate beads and compared to the chondrocyte cell lines C-28/I2 and SW1353. In addition, effects of interleukin-1beta (IL-1beta) or tumour necrosis factor-alpha (TNF-alpha) on primary cells were assessed. RESULTS Primary human chondrocytes predominantly express alpha-2,6-specific SiaTs and accordingly, alpha-2,6-linked sialic acid residues in glycoprotein N-glycans. In contrast, the preponderance of alpha-2,3-linked sialyl residues and, correspondingly, reduced levels of alpha-2,6-specific SiaTs are associated with the altered chondrocyte phenotype of C-28/I2 and SW1353 cells. Importantly, a considerable shift towards alpha-2,3-linked sialic acids and alpha-2,3-specific SiaT mRNA levels occurred in primary chondrocytes treated with IL-1beta or tumour necrosis factor-alpha (TNF-alpha). CONCLUSION The expression of the differentiated chondrocyte phenotype is linked to the ratio of alpha-2,6- to alpha-2,3-linked sialic acids in chondrocyte glycoprotein N-glycans. A shift towards altered sialylation might contribute to impaired cell-matrix interactions in disease conditions.
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Affiliation(s)
- S Toegel
- Medical University Vienna, Vienna, Austria,Laboratory for Cartilage Biology, Research Division, Hospital for Special Surgery, Weill Cornell Medical College, New York, USA,Corresponding author Stefan Toegel, Medical University Vienna, Waehringer Guertel 18–20, 1090 Vienna, Austria, Tel: 0043 1 4277 55461, Fax: 0043 1 4277 9554,
| | - M Pabst
- Department of Chemistry, University of Natural Resources and Applied Life Sciences, Vienna, Austria
| | - SQ Wu
- Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria,Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
| | - J Grass
- Department of Chemistry, University of Natural Resources and Applied Life Sciences, Vienna, Austria
| | - MB Goldring
- Laboratory for Cartilage Biology, Research Division, Hospital for Special Surgery, Weill Cornell Medical College, New York, USA
| | - C Chiari
- Department of Orthopedics, Medical University Vienna, Vienna, Austria
| | - A Kolb
- Department of Orthopedics, Medical University Vienna, Vienna, Austria
| | - F Altmann
- Department of Chemistry, University of Natural Resources and Applied Life Sciences, Vienna, Austria
| | - H Viernstein
- Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria
| | - FM Unger
- Department of Pharmaceutical Technology and Biopharmaceutics, University of Vienna, Vienna, Austria
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Kallifatidis G, Rausch V, Baumann B, Apel A, Beckermann BM, Groth A, Mattern J, Li Z, Kolb A, Moldenhauer G, Altevogt P, Wirth T, Werner J, Schemmer P, Büchler MW, Salnikov AV, Herr I. Sulforaphane targets pancreatic tumour-initiating cells by NF-kappaB-induced antiapoptotic signalling. Gut 2009; 58:949-63. [PMID: 18829980 DOI: 10.1136/gut.2008.149039] [Citation(s) in RCA: 169] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS Emerging evidence suggests that highly treatment-resistant tumour-initiating cells (TICs) play a central role in the pathogenesis of pancreatic cancer. Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is considered to be a novel anticancer agent; however, recent studies have shown that many pancreatic cancer cells are resistant to apoptosis induction by TRAIL due to TRAIL-activated nuclear factor-kappaB (NF-kappaB) signalling. Several chemopreventive agents are able to inhibit NF-kappaB, and favourable results have been obtained--for example, for the broccoli compound sulforaphane-in preventing metastasis in clinical studies. The aim of the study was to identify TICs in pancreatic carcinoma for analysis of resistance mechanisms and for definition of sensitising agents. METHODS TICs were defined by expression patterns of a CD44(+)/CD24(-), CD44(+)/CD24(+) or CD44(+)/CD133(+) phenotype and correlation to growth in immunodeficient mice, differentiation grade, clonogenic growth, sphere formation, aldehyde dehydrogenase (ALDH) activity and therapy resistance. RESULTS Mechanistically, specific binding of transcriptionally active cRel-containing NF-kappaB complexes in TICs was observed. Sulforaphane prevented NF-kappaB binding, downregulated apoptosis inhibitors and induced apoptosis, together with prevention of clonogenicity. Gemcitabine, the chemopreventive agents resveratrol and wogonin, and the death ligand TRAIL were less effective. In a xenograft model, sulforaphane strongly blocked tumour growth and angiogenesis, while combination with TRAIL had an additive effect without obvious cytotoxicity in normal cells. Freshly isolated patient tumour cells expressing markers for TICs could be sensitised by sulforaphane for TRAIL-induced cytotoxicity. CONCLUSION The data provide new insights into resistance mechanisms of TICs and suggest the combination of sulforaphane with TRAIL as a promising strategy for targeting of pancreatic TICs.
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Affiliation(s)
- G Kallifatidis
- Molecular OncoSurgery Group, University of Heidelberg and German Cancer Research Center, Heidelberg, Germany
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Itzykson R, Ayari S, Vassilief D, Berger E, Slama B, Vey N, Suarez F, Beyne-Rauzy O, Guerci A, Cheze S, Thomas X, Stamatoullas A, Gardembas M, Bauduer F, Kolb A, Chaury MC, Legros L, Damaj G, Chermat F, Dreyfus F, Fenaux P, Ades L. Is there a role for all-trans retinoic acid in combination with recombinant erythropoetin in myelodysplastic syndromes? A report on 59 cases. Leukemia 2009; 23:673-8. [PMID: 19151787 DOI: 10.1038/leu.2008.362] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Erythropoiesis-stimulating agents (ESAs) remain the first-line treatment of anemia in lower risk myelodysplastic syndromes (MDS) without 5q deletion. A preliminary report suggested that adding all-trans retinoic acid (ATRA) to ESAs may improve their erythroid response, particularly in patients with high endogenous erythropoietin (EPO) level, and may improve other cytopenias. We conducted a prospective multicenter study of EPO-beta and ATRA in anemic MDS patients with marrow blasts <10% and either previous ESA failure or relapse, endogenous EPO >500 U/l or other cytopenia(s) (absolute neutrophilic count <1.0 G/l or platelets <50 G/l). A total of 59 patients were evaluable after 12 weeks of treatment. The erythroid response rates according to IWG 2000 and 2006 criteria, respectively, were as follows: overall: 49 and 36%; patients with previous ESA failure (n=28): 43 and 32%; patients with endogenous EPO >500 U/l (n=18): 11 and 19%; patients transfused >2 red blood cells units/month (n=28) 43 and 39%. Only one neutrophil, but no platelet response, and no major side effect were observed. EPO-beta-ATRA combination appears a possible therapeutic option in anemia of MDS having failed an ESA alone, but not in patients with high endogenous EPO level, and does not improve neutropenia and thrombocytopenia.
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Affiliation(s)
- R Itzykson
- Service d'Hématologie Clinique, Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Avicenne-Paris 13 University, Bobigny, France
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Abstract
Macroscopic and microscopic complete resection, i.e. R0 resection, is a basic principle of oncologic hepatopancreatobiliary (HPB) surgery. The reported R1 rates for different HPB tumor entities vary considerably, most likely because of ambiguities in the exact definition of R1 resection and the lack of standardized histopathologic examination and reporting. R1 resections can be interpreted as technical/surgical failure (e.g. for small, peripherally located liver tumors). In most cases, however, R1 resections are determined by the anatomic location of the tumor and the growth pattern (e.g. pancreatic cancer with perineural invasion). R0 resections have been identified as positive predictive markers for several HPB tumors (in comparison to R1 resection). Therefore HPB surgeons should always aim at macroscopic and microscopic complete resections. Nonetheless, R1 resections often provide an advantage over no resection with respect to survival and quality of life in patients with these tumors.
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Affiliation(s)
- A Kolb
- Chirurgische Klinik, Universität Heidelberg, Im Neuenheimer Feld 110, 69120 Heidelberg, Germany
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Zhang C, Kolb A, Mattern J, Gassler N, Wenger T, Herzer K, Debatin KM, Büchler M, Friess H, Rittgen W, Edler L, Herr I. Dexamethasone desensitizes hepatocellular and colorectal tumours toward cytotoxic therapy. Cancer Lett 2005; 242:104-11. [PMID: 16338063 DOI: 10.1016/j.canlet.2005.10.037] [Citation(s) in RCA: 29] [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] [Received: 08/08/2005] [Revised: 10/25/2005] [Accepted: 10/26/2005] [Indexed: 01/05/2023]
Abstract
The glucocorticoid dexamethasone is frequently used as co-treatment in cytotoxic cancer therapy, e.g. to prevent nausea, to protect normal tissue or for other reasons. While the potent pro-apoptotic properties and the supportive effects of glucocorticoids to tumour therapy in lymphoid cells are well studied, the impact to cytotoxic treatment of colorectal and hepatocellular carcinoma is unknown. We tested apoptosis-induction, viability, tumour growth and protein expression using 8 established cell lines, 18 surgical specimen and a xenograft on nude mice. In the presence of dexamethasone we found strong inhibition of apoptosis in response to 5-FU, cisplatin, gemcitabine or gamma-irradiation, enhanced viability and tumour growth of colorectal and hepatocellular carcinomas. No correlation with age, gender, histology, TNM, the p53 status and induction of therapy resistance by dexamethasone co-treatment could be detected. These data show that glucocorticoid-induced resistance occurs not occasionally but is common in colorectal and hepatocellular carcinomas implicating that the use of glucocorticoids may be harmful for cancer patients.
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Affiliation(s)
- C Zhang
- Molecular Urooncology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
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Kolb A, Kleeff J, Guweidhi A, Esposito I, Giese NA, Adwan H, Giese T, Büchler MW, Berger MR, Friess H. Osteopontin influences the invasiveness of pancreatic cancer cells and is increased in neoplastic and inflammatory conditions. Cancer Biol Ther 2005; 4:740-6. [PMID: 15970685 DOI: 10.4161/cbt.4.7.1821] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies, with an overall 5-year survival rate of less than 5%. Invasive tumor growth and early metastasis are two important reasons for this dismal prognosis. Osteopontin (OPN) is a secretory protein with a variety of functions, for example in cell adhesion and migration, inflammatory reaction and apoptosis. In this study the functional role of OPN in human pancreatic cancer and its potential use as a disease marker were analyzed. By real time quantitative PCR, there was a 2.2-fold and 1.6-fold increase of OPN mRNA in pancreatic cancers (n = 23) and chronic pancreatitis samples (n = 22), respectively, compared to normal pancreatic tissues (n = 20). Immunohistochemical analysis demonstrated OPN staining in 60% of the primary pancreatic tumors and in 72% of the lymph node and liver metastases. ELISA analysis of serum samples obtained from pancreatic cancer patients (n = 70), chronic pancreatitis patients (n = 12), and healthy donors (n = 20) showed a 1.6-fold increase in OPN serum levels in patients with tumors and a 1.9-fold increase in patients with chronic pancreatitis. Recombinant human OPN significantly increased the invasiveness of pancreatic cancer cells, without having any impact on cell proliferation. In addition, down regulation of OPN by specific siRNA molecules decreased pancreatic cancer cell invasion. In conclusion, OPN serum levels in pancreatic cancer and chronic pancreatitis patients are not significantly different, thereby restricting its role as a prognostic or follow-up marker. Our results do suggest, however, that blockade of OPN might be useful as a therapeutic approach to inhibit invasion and metastasis of pancreatic cancer cells.
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Affiliation(s)
- A Kolb
- Department of General Surgery, University of Heidelberg, Germany
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Schweitzer D, Beuermann B, Hammer M, Schweitzer F, Richter S, Leistritz L, Scibor M, Thamm E, Kolb A, Anders R. Fundusspektrometrie bei altersbezogener Makulopathie. Klin Monbl Augenheilkd 2005; 222:396-408. [PMID: 15912457 DOI: 10.1055/s-2005-858088] [Citation(s) in RCA: 3] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Spectroscopic methods permit the non-invasive detection of fundus pigments by the wavelength-dependent absorption of fluorescence as well as by the fluorescence lifetime. From the relative concentrations of haemoglobin and oxyhaemoglobin, the oxygen saturation can be calculated. The onset of age-related maculopathy might be delayed by a high optical density of xanthophyll. The detection of alterations in fundus autofluorescence points to age-related pathomechanisms (accumulation of lipofuscin, formation of connective tissue). The detection of autofluorescence of redox-pairs of coenzymes results in information about metabolic states at the cellular level, and might make possible an early detection of age-related changes when they are still reversible. METHOD The evaluation of reflectance spectra, detected by imaging ophthalmo-spectrometry, results in the calculation of oxygen saturation or in the optical density of xanthophyll or of melanin. Fluorescence spectra can be measured also by this technique. For the 2-dimensional determination of the distribution of xanthophyll, a very simple method was developed, requiring fundus illumination by one wavelength only. In the detection of time-resolved autofluorescence, the fluorescence lifetime is used for the determination of endogenous fluorophores. RESULTS As result of comparing studies between ARM patients and healthy subjects, the consumption of retinal oxygen was increased already in the children of ARM patients. An increasing optical density of xanthophyll was determined after lutein supplementation. Differences in fluorescence lifetime were determined between ARM patients and healthy subjects, but their interpretation requires investigations of cell or of organ model cultures. CONCLUSIONS The described methods permit in vivo basic investigations of ARM and can be considered as impulses for the development of diagnostic devices.
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Affiliation(s)
- D Schweitzer
- FSU Jena, Klinik für Augenheilkunde, Bereich Experimentelle Ophthalmologie, Jena.
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Kolb A, Gollackner M, Klepp KO. Crystal structure of tetrarubidium hexathiodisilicate(IV), Rb4Si2S6. Z KRIST-NEW CRYST ST 2004. [DOI: 10.1524/ncrs.2004.219.14.393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Muehling B, Kolb A, Ramadani M, Schmidt E, Gansauge F, Beger HG. Comparative analysis of extracellular matrix proteins in chronic pancreatitis: differences between pancreatic head and tail. Pancreas 2004; 28:174-80. [PMID: 15028950 DOI: 10.1097/00006676-200403000-00009] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
OBJECTIVES In patients with chronic pancreatitis (cP) with an inflammatory mass in the pancreatic head, the degree of fibrosis in the pancreatic head compared with the tail should be determined and differences in the expression pattern of collagen types I, III, and IV; laminin; vitronectin; and fibronectin should be evaluated. METHODS From 12 patients with alcohol-induced and idiopathic cP who underwent surgery due to local complications, 24 corresponding cP tissue samples from the pancreatic head and the resection margin were obtained. The degree of fibrosis was calculated using a computer-assisted method (Adobe Photo Shop). The expression pattern of extracellular matrix proteins (ECMPs) was investigated by immunostaining using the streptavidin-peroxidase technique. RESULTS In each case, the degree of fibrosis was higher in the pancreatic head than in the resection margin. For alcohol-induced cP, the median degree of fibrosis in the head was 64% versus 47% in the resection margin, and for idiopathic cP, it was 40% versus 32%. Staining intensity of collagen type IV and laminin in the head was higher than in the resection surface. In degenerative tissue, collagen types I, III, and IV and laminin were moderately expressed, fibronectin was weakly expressed, and vitronectin was not expressed, with no differences between the head and resection margin. Basement membranes in the head and the resection margin predominantly consisted of collagen types I, III, and IV and laminin. In ductal epithelia, collagen type IV staining in the head was stronger than in the resection margin. CONCLUSIONS In cP with an inflammatory mass in the head, the degree of fibrosis in the pancreatic head is higher than in the resection margin. Differences in the expression pattern of ECMPs could be detected for collagen type IV and laminin. These results underline the hypothesis of the pancreatic head being the pacemaker of cP in which collagen type IV and laminin may play an important role.
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Affiliation(s)
- B Muehling
- Department of General, Visceral, and Transplantation Surgery, University of Ulm, Ulm,
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Boulad F, Auerbach A, Kolb A, Small T, Prasad V, Prockop S, Torok-Castanza J, Casson A, Collins N, Kernan N, O’Reilly R. Hematopoietic stem cell transplantation for the treatment of fanconi anemia using a fludarabine-based cytoreductive regimen and T-cell depleted grafts from alternative donors. Biol Blood Marrow Transplant 2004. [DOI: 10.1016/j.bbmt.2003.12.186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Boulad F, Steinherz P, Kernan N, Small T, Prasad V, Prockop S, Kolb A, O’Reilly R. Allogeneic bone marrow transplantation (BMT) for the treatment of children with very high risk acute lymphoblastic leukemia (ALL) in first remission (CR1). Biol Blood Marrow Transplant 2004. [DOI: 10.1016/j.bbmt.2003.12.108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Affiliation(s)
- S Busby
- School of Biochemistry, University of Birmingham, UK
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Abstract
The detection of metabolic changes opens the possibility for intervention of reversible pathological alterations. Measurements of oxygen saturation are limited to the blood vessel system. Detection of alterations in oxygen concentrations are up to 3 orders of magnitude more sensitive by autofluorescence of coenzymes than by measurement of oxygen saturation. Because of limited transmission of the ocular media no specific excitation of endogenous fluorophores can be realised. For this reason it was investigated if the fluorescence lifetime after pulse excitation can be detected at the human fundus. Applying a laser scanner ophthalmoscope and mode-locked Ar(+) laser as well as time-correlated single photon counting, lifetime images of the living fundus were obtained. In mono-exponential approximation, a mean lifetime of 5 ns was detected from the optic disc and large vessels whereas about 1.5 ns were detected in the parapapillary area. By evaluating the frequency of lifetimes, lipofuscin, free FAD, and collagen are probably detectable. Comparative measurements were performed in fundus specimens and on free FAD.
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Affiliation(s)
- D Schweitzer
- Augenklinik der FSU Jena, Bereich Experimentelle Ophthalmologie, Germany.
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Bordes P, Bouvier J, Conter A, Kolb A, Gutierrez C. Transient repressor effect of Fis on the growth phase-regulated osmE promoter of Escherichia coli K12. Mol Genet Genomics 2002; 268:206-13. [PMID: 12395194 DOI: 10.1007/s00438-002-0733-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2002] [Accepted: 07/03/2002] [Indexed: 11/27/2022]
Abstract
Transcription of the gene osmE of Escherichia coli is osmotically inducible and regulated by the growth phase. Expression of osmE is directed by a single promoter, osmE (p), which is recognized by Esigma(70) and Esigma(s), two forms of RNA polymerase using, respectively, the sigma factors sigma(70) and sigma(s). Esigma(s) transcribes osmE (p) during entry into stationary phase. Esigma(70) is responsible for osmotic induction of osmE (p) during the exponential growth phase. In a search for proteins that can modulate osmE (p) expression in trans, we performed electrophoretic mobility shift experiments using a DNA fragment carrying osmE (p) and crude extracts from E. coli. One major retarded band was observed in these experiments. The Fis protein is responsible for this retarded band, and binds to several sites upstream and downstream of, and overlapping, the promoter region of osmE. In a fis mutant background, the kinetics of in vivo transcription of osmE (p) during growth demonstrated that Fis is not responsible for the repression of the promoter seen during early exponential phase. In contrast, expression of osmE (p) at elevated osmolarity during the mid-exponential growth phase is increased in the absence of Fis, demonstrating that Fis is able to act as a repressor in vivo at a particular stage of growth.
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Affiliation(s)
- P Bordes
- Laboratoire de Microbiologie et Génétique Moléculaire, UMR 5100 CNRS-Université Toulouse III, 118 Route de Narbonne, F-31062 Toulouse Cedex, France
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Abstract
GOAL To determine the coefficient and the anisotropy of scattering as well as the refractive indices in the retina and in the choroid noninvasively in vivo. METHODS The power of coherent reflected light versus fundus depth is recorded in OCT-A-scans. The ratio of refractive indices is derived from the height of the reflection peaks. Provided that the absorption coefficient is known from fundus reflectometry, the scattering coefficient and anisotropy are calculated from the offset and the slope of the signal behind the reflection peaks on the basis of a single backscattering model. RESULTS We found scattering coefficients of 12/mm (retina) and 27.5/mm (choroid) as well as anisotropy values of 0.97 (retina) and 0.90 (choroid). DISCUSSION The OCT is usually employed for the measurement of intraocular distances. The new technique described here gives the unique opportunity to determine further interesting parameters of single ocular layers. The values given above are in good agreement with in vitro results.
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Affiliation(s)
- H Hammer
- University of Jena, Department of Ophthalmology, Germany
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