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Durán-Carabali LE, Odorcyk FK, Grun LK, Schmitz F, Ramires Junior OV, de Oliveria MR, Campos KF, Hoeper E, Carvalho AVS, Greggio S, Venturine GT, Zimmer ER, Barbé-Tuana F, Wyse ATS, Netto CA. Maternal environmental enrichment protects neonatal brains from hypoxic-ischemic challenge by mitigating brain energetic dysfunction and modulating glial cell responses. Exp Neurol 2024; 374:114713. [PMID: 38325654 DOI: 10.1016/j.expneurol.2024.114713] [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: 10/03/2023] [Revised: 01/31/2024] [Accepted: 02/03/2024] [Indexed: 02/09/2024]
Abstract
There is evidence that maternal milieu and changes in environmental factors during the prenatal period may exert a lasting impact on the brain health of the newborn, even in case of neonatal brain hypoxia-ischemia (HI). The present study aimed to investigate the effects of maternal environmental enrichment (EE) on HI-induced energetic and metabolic failure, along with subsequent neural cell responses in the early postnatal period. Male Wistar pups born to dams exposed to maternal EE or standard conditions (SC) were randomly divided into Sham-SC, HI-SC, Sham-EE, and HI-EE groups. Neonatal HI was induced on postnatal day (PND) 3. The Na+,K+-ATPase activity, mitochondrial function and neuroinflammatory related-proteins were assessed at 24 h and 48 h after HI. MicroPET-FDG scans were used to measure glucose uptake at three time points: 24 h post-HI, PND18, and PND24. Moreover, neuronal preservation and glial cell responses were evaluated at PND18. After HI, animals exposed to maternal EE showed an increase in Na+,K+-ATPase activity, preservation of mitochondrial potential/mass ratio, and a reduction in mitochondrial swelling. Glucose uptake was preserved in HI-EE animals from PND18 onwards. Maternal EE attenuated HI-induced cell degeneration, white matter injury, and reduced astrocyte immunofluorescence. Moreover, the HI-EE group exhibited elevated levels of IL-10 and a reduction in Iba-1 positive cells. Data suggested that the regulation of AKT/ERK1/2 signaling pathways could be involved in the effects of maternal EE. This study evidenced that antenatal environmental stimuli could promote bioenergetic and neural resilience in the offspring against early HI damage, supporting the translational value of pregnancy-focused environmental treatments.
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Affiliation(s)
- L E Durán-Carabali
- Graduate Program in Biological Sciences: Physiology, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
| | - F K Odorcyk
- Graduate Program in Biological Sciences: Biochemistry, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - L K Grun
- Group of Inflammation and Cellular Senescence, Graduate Program in Cellular and Molecular Biology, School of Sciences, Pontificia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil
| | - F Schmitz
- Graduate Program in Biological Sciences: Biochemistry, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; Neuroprotection and Neurometabolic Diseases Laboratory (Wyse's Lab.), Brazil
| | - O V Ramires Junior
- Graduate Program in Biological Sciences: Biochemistry, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; Neuroprotection and Neurometabolic Diseases Laboratory (Wyse's Lab.), Brazil
| | - M R de Oliveria
- Department of Morphology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - K F Campos
- Graduate Program in Biological Sciences: Physiology, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - E Hoeper
- Graduate Program in Biological Sciences: Neuroscience, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - A V S Carvalho
- Graduate Program in Biological Sciences: Biochemistry, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - S Greggio
- Undergraduate Program in Biomedicine, School of Health and Life Sciences, Pontificia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil; Preclinical Research Center, Brain Institute (BraIns) of Rio Grande do Sul, Porto Alegre, Brazil
| | - G T Venturine
- Preclinical Research Center, Brain Institute (BraIns) of Rio Grande do Sul, Porto Alegre, Brazil
| | - E R Zimmer
- Graduate Program in Biological Sciences: Pharmacology and Therapeutics, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; Department of Pharmacology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - F Barbé-Tuana
- Group of Inflammation and Cellular Senescence, Graduate Program in Cellular and Molecular Biology, School of Sciences, Pontificia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil
| | - A T S Wyse
- Neuroprotection and Neurometabolic Diseases Laboratory (Wyse's Lab.), Brazil; Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - C A Netto
- Graduate Program in Biological Sciences: Physiology, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
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Schmitz F, Knöchelmann E, Kruse T, Minceva M, Kampmann M. Continuous multi-column capture of monoclonal antibodies with convective diffusive membrane adsorbers. Biotechnol Bioeng 2024. [PMID: 38470343 DOI: 10.1002/bit.28695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/26/2024] [Accepted: 02/27/2024] [Indexed: 03/13/2024]
Abstract
Downstream processing is the bottleneck in the continuous manufacturing of monoclonal antibodies (mAbs). To overcome throughput limitations, two different continuous processes with a novel convective diffusive protein A membrane adsorber (MA) were investigated: the rapid cycling parallel multi-column chromatography (RC-PMCC) process and the rapid cycling simulated moving bed (RC-BioSMB) process. First, breakthrough curve experiments were performed to investigate the influence of the flow rate on the mAb dynamic binding capacity and to calculate the duration of the loading steps. In addition, customized control software was developed for an automated MA exchange in case of pressure increase due to membrane fouling to enable robust, uninterrupted, and continuous processing. Both processes were performed for 4 days with 0.61 g L-1 mAb-containing filtrate and process performance, product purity, productivity, and buffer consumption were compared. The mAb was recovered with a yield of approximately 90% and productivities of 1010 g L-1 d-1 (RC-PMCC) and 574 g L-1 d-1 (RC-BioSMB). At the same time, high removal of process-related impurities was achieved with both processes, whereas the buffer consumption was lower for the RC-BioSMB process. Finally, the attainable productivity for perfusion bioreactors of different sizes with suitable MA sizes was calculated to demonstrate the potential to operate both processes on a manufacturing scale with bioreactor volumes of up to 2000 L.
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Affiliation(s)
- Fabian Schmitz
- Biothermodynamics, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
- Corporate Research, Sartorius Stedim Biotech GmbH, Göttingen, Germany
| | - Elias Knöchelmann
- Corporate Research, Sartorius Stedim Biotech GmbH, Göttingen, Germany
| | - Thomas Kruse
- Corporate Research, Sartorius Stedim Biotech GmbH, Göttingen, Germany
| | - Mirjana Minceva
- Biothermodynamics, TUM School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Markus Kampmann
- Corporate Research, Sartorius Stedim Biotech GmbH, Göttingen, Germany
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Schmitz F, Röder A, Hoffrogge M, Urlacher VB, Koschorreck K. Agar plate-based activity assay for easy and fast screening of recombinant Pichia pastoris expressing unspecific peroxygenases. Biotechnol J 2024; 19:e2300421. [PMID: 38044796 DOI: 10.1002/biot.202300421] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 11/14/2023] [Accepted: 11/30/2023] [Indexed: 12/05/2023]
Abstract
Unspecific peroxygenases (UPOs) are promising biocatalysts that catalyze oxyfunctionalization reactions without the need for costly cofactors. Pichia pastoris (reclassified as Komagataella phaffii) is considered an attractive host for heterologous expression of UPOs. However, integration of UPO-expression cassettes into the genome via a single cross-over yields recombinant Pichia transformants with different UPO gene copy numbers resulting in different expression levels. Selection of the most productive Pichia transformants by a commonly used screening in liquid medium in 96-well plates is laborious and lasts up to 5 days. In this work, we developed a simple two-step agar plate-based assay to screen P. pastoris transformants for UPO activity with less effort, within shorter time, and without automated screening devices. After cell growth and protein expression on agar plates supplemented with methanol and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), an additional top agar layer supplemented with ABTS and peroxide is added. UPO activity is visualized within 15 min by formation of green zones around UPO-secreting P. pastoris transformants. The assay was validated with two UPOs, AbrUPO from Aspergillus brasiliensis and evolved PaDa-I from Agrocybe aegerita. The assay results were confirmed in a quantitative 96-deep well plate screening in liquid medium.
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Affiliation(s)
- Fabian Schmitz
- Institute of Biochemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, Düsseldorf, Germany
| | - Annika Röder
- Institute of Biochemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, Düsseldorf, Germany
| | - Maike Hoffrogge
- Institute of Biochemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, Düsseldorf, Germany
| | - Vlada B Urlacher
- Institute of Biochemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, Düsseldorf, Germany
| | - Katja Koschorreck
- Institute of Biochemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, Düsseldorf, Germany
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Bieber A, Müller K, Kools S, Hilker L, Ebner L, Kirchgässler A, Rohmann R, Kleinz T, Ortmann L, Basner L, Kühn E, Averdunk P, Schmitz F, Bulut Y, Huckemann S, Scholz L, Fisse A, Motte J, Grüter T, Kwon E, Schneider-Gold C, Gold R, Tönges L, Pitarokoili K. P-99 Nerve conduction studies in a cohort of patients with Parkinson[StQuote]s disease, multiple system atrophy and progressive supranuclear palsy. Clin Neurophysiol 2023. [DOI: 10.1016/j.clinph.2023.02.116] [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: 03/08/2023]
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Schmitz F, Kruse T, Minceva M, Kampmann M. Integrated double flow-through purification of monoclonal antibodies using membrane adsorbers and single-pass tangential flow filtration. Biochem Eng J 2023. [DOI: 10.1016/j.bej.2023.108913] [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: 03/29/2023]
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Schmitz F, Lago N, Fagiolari L, Burkhart J, Cester A, Polo A, Prato M, Meneghesso G, Gross S, Bella F, Lamberti F, Gatti T. High Open-Circuit Voltage Cs 2 AgBiBr 6 Carbon-Based Perovskite Solar Cells via Green Processing of Ultrasonic Spray-Coated Carbon Electrodes from Waste Tire Sources. ChemSusChem 2022; 15:e202201927. [PMID: 36328732 DOI: 10.1002/cssc.202201927] [Citation(s) in RCA: 1] [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] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Invited for this month cover is the group of Teresa Gatti at the Justus Liebig University (JLU) in Giessen, Germany, the group of Federico Bella at Politecnico di Torino (POLITO), Italy, and the group of Francesco Lamberti at the University of Padova (UNIPD), also in Italy. The image shows how waste tires can be converted in a conductive carbon powder that undergoes a green processing step to produce carbon electrodes for lead-free perovskite solar cells. Similar devices can be employed to harvest indoor light in order to power the Internet of Things (IoT) ecosystem. The Research Article itself is available at 10.1002/cssc.202201590.
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Affiliation(s)
- Fabian Schmitz
- Institute of Physical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392, Giessen, Germany
- Center for Materials Research, Justus Liebig University, Heinrich-Buff-Ring 17, 35392, Giessen, Germany
| | - Nicolò Lago
- Department of Information Engineering, University of Padova, Via Gradenigo 6/B, 35131, Padova, Italy
| | - Lucia Fagiolari
- Department of Applied Science and Technology, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129, Torino, Italy
| | - Julian Burkhart
- Institute of Physical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392, Giessen, Germany
| | - Andrea Cester
- Department of Information Engineering, University of Padova, Via Gradenigo 6/B, 35131, Padova, Italy
| | - Andrea Polo
- Department of Information Engineering, University of Padova, Via Gradenigo 6/B, 35131, Padova, Italy
| | - Mirko Prato
- Materials Characterization Facility, Istituto Italiano di Tecnologia, Via Morego 30, 16163, Genova, Italy
| | - Gaudenzio Meneghesso
- Department of Information Engineering, University of Padova, Via Gradenigo 6/B, 35131, Padova, Italy
- Center "Giorgio Levi Cases" for Energy Economics and Technology, Via Marzolo 9, 35131, Padova, Italy
| | - Silvia Gross
- Center "Giorgio Levi Cases" for Energy Economics and Technology, Via Marzolo 9, 35131, Padova, Italy
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131, Padova, Italy
| | - Federico Bella
- Department of Applied Science and Technology, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129, Torino, Italy
| | - Francesco Lamberti
- Center "Giorgio Levi Cases" for Energy Economics and Technology, Via Marzolo 9, 35131, Padova, Italy
- Department of Chemical Sciences, University of Padova, Via Marzolo 1, 35131, Padova, Italy
| | - Teresa Gatti
- Institute of Physical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392, Giessen, Germany
- Center for Materials Research, Justus Liebig University, Heinrich-Buff-Ring 17, 35392, Giessen, Germany
- Department of Applied Science and Technology, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129, Torino, Italy
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Schmitz F, Lago N, Fagiolari L, Burkhart J, Cester A, Polo A, Prato M, Meneghesso G, Gross S, Bella F, Lamberti F, Gatti T. High Open-Circuit Voltage Cs 2 AgBiBr 6 Carbon-Based Perovskite Solar Cells via Green Processing of Ultrasonic Spray-Coated Carbon Electrodes from Waste Tire Sources. ChemSusChem 2022; 15:e202201590. [PMID: 36073538 PMCID: PMC9828808 DOI: 10.1002/cssc.202201590] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/07/2022] [Indexed: 06/15/2023]
Abstract
Costs and toxicity concerns are at the center of a heated debate regarding the implementation of perovskite solar cells (PSCs) into commercial products. The first bottleneck could be overcome by eliminating the top metal electrode (generally gold) and the underlying hole transporting material and substituting both with one single thick layer of conductive carbon, as in the so-called carbon-based PSCs (C-PSCs). The second issue, related to the presence of lead, can be tackled by resorting to other perovskite structures based on less toxic metallic components. An interesting case is that of the double perovskite Cs2 AgBiBr6 , which at present still lacks the outstanding optoelectronic performances of the lead-based counterparts but is very stable to environmental factors. In this work, the processing of carbon electrodes onto Cs2 AgBiBr6 -based C-PSCs was reported, starting from an additive-free isopropanol ink of a carbon material obtained from the hydrothermal recycling of waste tires and employing a high-throughput ultrasonic spray coating method in normal environmental conditions. Through this highly sustainable approach that ensures a valuable step from an end-of-life to an end-of-waste status for used tires, devices were obtained delivering a record open circuit voltage of 1.293 V, which might in the future represent ultra-cheap solutions to power the indoor Internet of Things ecosystem.
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Affiliation(s)
- Fabian Schmitz
- Institute of Physical ChemistryJustus Liebig UniversityHeinrich-Buff-Ring 1735392GiessenGermany
- Center for Materials ResearchJustus Liebig UniversityHeinrich-Buff-Ring 1735392GiessenGermany
| | - Nicolò Lago
- Department of Information EngineeringUniversity of PadovaVia Gradenigo 6/B35131PadovaItaly
| | - Lucia Fagiolari
- Department of Applied Science and TechnologyPolitecnico di TorinoC.so Duca degli Abruzzi 2410129TorinoItaly
| | - Julian Burkhart
- Institute of Physical ChemistryJustus Liebig UniversityHeinrich-Buff-Ring 1735392GiessenGermany
| | - Andrea Cester
- Department of Information EngineeringUniversity of PadovaVia Gradenigo 6/B35131PadovaItaly
| | - Andrea Polo
- Department of Information EngineeringUniversity of PadovaVia Gradenigo 6/B35131PadovaItaly
| | - Mirko Prato
- Materials Characterization FacilityIstituto Italiano di TecnologiaVia Morego 3016163GenovaItaly
| | - Gaudenzio Meneghesso
- Department of Information EngineeringUniversity of PadovaVia Gradenigo 6/B35131PadovaItaly
- Center “Giorgio Levi Cases” for Energy Economics and TechnologyVia Marzolo 935131PadovaItaly
| | - Silvia Gross
- Center “Giorgio Levi Cases” for Energy Economics and TechnologyVia Marzolo 935131PadovaItaly
- Department of Chemical SciencesUniversity of PadovaVia Marzolo 135131PadovaItaly
| | - Federico Bella
- Department of Applied Science and TechnologyPolitecnico di TorinoC.so Duca degli Abruzzi 2410129TorinoItaly
| | - Francesco Lamberti
- Center “Giorgio Levi Cases” for Energy Economics and TechnologyVia Marzolo 935131PadovaItaly
- Department of Chemical SciencesUniversity of PadovaVia Marzolo 135131PadovaItaly
| | - Teresa Gatti
- Institute of Physical ChemistryJustus Liebig UniversityHeinrich-Buff-Ring 1735392GiessenGermany
- Center for Materials ResearchJustus Liebig UniversityHeinrich-Buff-Ring 1735392GiessenGermany
- Department of Applied Science and TechnologyPolitecnico di TorinoC.so Duca degli Abruzzi 2410129TorinoItaly
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Schmitz F, Neisius R, Horn J, Sann J, Schlettwein D, Gerhard M, Gatti T. Tuning the optical properties of 2D monolayer silver-bismuth bromide double perovskite by halide substitution. Nanotechnology 2022; 33:215706. [PMID: 35158342 DOI: 10.1088/1361-6528/ac54df] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 02/14/2022] [Indexed: 06/14/2023]
Abstract
Silver-bismuth double perovskites are promising replacement materials for lead-based ones in photovoltaic (PV) devices due to the lower toxicity and enhanced stability to environmental factors. In addition, they might even be more suitable for indoor PV, due to the size of their bandgap better matching white LEDs emission. Unfortunately, their optoelectronic performance does not reach that of the lead-based counterparts, because of the indirect nature of the band gap and the high exciton binding energy. One strategy to improve the electronic properties is the dimensional reduction from the 3D to the 2D perovskite structure, which features a direct band gap, as it has been reported for 2D monolayer derivates of Cs2AgBiBr6obtained by substituting Cs+cations with bulky alkylammonium cations. However, a similar dimensional reduction also brings to a band gap opening, limiting light absorption in the visible. In this work, we report on the achievement of a bathochromic shift in the absorption features of a butylammonium-based silver-bismuth bromide monolayer double perovskite through doping with iodide and study the optical properties and stability of the resulting thin films in environmental conditions. These species might constitute the starting point to design future sustainable materials to implement as active components in indoor photovoltaic devices used to power the IoT.
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Affiliation(s)
- Fabian Schmitz
- Institute of Physical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
- Center for Materials Research, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
| | - Raphael Neisius
- Institute of Physical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
| | - Jonas Horn
- Center for Materials Research, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
- Institute of Applied Physics, Justus Liebig University, Heinrich Buff Ring 16, 35392 Giessen, Germany
| | - Joachim Sann
- Institute of Physical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
- Center for Materials Research, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
| | - Derck Schlettwein
- Center for Materials Research, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
- Institute of Applied Physics, Justus Liebig University, Heinrich Buff Ring 16, 35392 Giessen, Germany
| | - Marina Gerhard
- Faculty of Physics and Materials Science Center, Philipps-Universität Marburg, Renthof 7a, Marburg D-35032, Germany
| | - Teresa Gatti
- Institute of Physical Chemistry, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
- Center for Materials Research, Justus Liebig University, Heinrich-Buff-Ring 17, 35392 Giessen, Germany
- Centre of Excellence ENSEMBLE 3 sp. z o.o., Wolczynska 133, Warsaw, 01-919, Poland
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Chernomor O, Peters L, Schneidewind J, Loeschcke A, Knieps-Grünhagen E, Schmitz F, von Lieres E, Kutta RJ, Svensson V, Jaeger KE, Drepper T, von Haeseler A, Krauss U. Complex Evolution of Light-Dependent Protochlorophyllide Oxidoreductases in Aerobic Anoxygenic Phototrophs: Origin, Phylogeny, and Function. Mol Biol Evol 2021; 38:819-837. [PMID: 32931580 PMCID: PMC7947762 DOI: 10.1093/molbev/msaa234] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Light-dependent protochlorophyllide oxidoreductase (LPOR) and dark-operative protochlorophyllide oxidoreductase are evolutionary and structurally distinct enzymes that are essential for the synthesis of (bacterio)chlorophyll, the primary pigment needed for both anoxygenic and oxygenic photosynthesis. In contrast to the long-held hypothesis that LPORs are only present in oxygenic phototrophs, we recently identified a functional LPOR in the aerobic anoxygenic phototrophic bacterium (AAPB) Dinoroseobacter shibae and attributed its presence to a single horizontal gene transfer event from cyanobacteria. Here, we provide evidence for the more widespread presence of genuine LPOR enzymes in AAPBs. An exhaustive bioinformatics search identified 36 putative LPORs outside of oxygenic phototrophic bacteria (cyanobacteria) with the majority being AAPBs. Using in vitro and in vivo assays, we show that the large majority of the tested AAPB enzymes are genuine LPORs. Solution structural analyses, performed for two of the AAPB LPORs, revealed a globally conserved structure when compared with a well-characterized cyanobacterial LPOR. Phylogenetic analyses suggest that LPORs were transferred not only from cyanobacteria but also subsequently between proteobacteria and from proteobacteria to Gemmatimonadetes. Our study thus provides another interesting example for the complex evolutionary processes that govern the evolution of bacteria, involving multiple horizontal gene transfer events that likely occurred at different time points and involved different donors.
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Affiliation(s)
- Olga Chernomor
- Center for Integrative Bioinformatics Vienna, Max Perutz Labs, University of Vienna, Medical University of Vienna, Vienna, Austria
| | - Lena Peters
- Institut für Molekulare Enzymtechnologie, Heinrich-Heine-Universität Düsseldorf, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Judith Schneidewind
- Institut für Molekulare Enzymtechnologie, Heinrich-Heine-Universität Düsseldorf, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Anita Loeschcke
- Institut für Molekulare Enzymtechnologie, Heinrich-Heine-Universität Düsseldorf, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Esther Knieps-Grünhagen
- Institut für Molekulare Enzymtechnologie, Heinrich-Heine-Universität Düsseldorf, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Fabian Schmitz
- Institut für Molekulare Enzymtechnologie, Heinrich-Heine-Universität Düsseldorf, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Eric von Lieres
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Roger Jan Kutta
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, Regensburg, Germany
| | - Vera Svensson
- Institut für Molekulare Enzymtechnologie, Heinrich-Heine-Universität Düsseldorf, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Karl-Erich Jaeger
- Institut für Molekulare Enzymtechnologie, Heinrich-Heine-Universität Düsseldorf, Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Thomas Drepper
- Institut für Molekulare Enzymtechnologie, Heinrich-Heine-Universität Düsseldorf, Forschungszentrum Jülich GmbH, Jülich, Germany
| | - Arndt von Haeseler
- Center for Integrative Bioinformatics Vienna, Max Perutz Labs, University of Vienna, Medical University of Vienna, Vienna, Austria
- Faculty of Computer Science, University of Vienna, Vienna, Austria
| | - Ulrich Krauss
- Institut für Molekulare Enzymtechnologie, Heinrich-Heine-Universität Düsseldorf, Forschungszentrum Jülich GmbH, Jülich, Germany
- Institute of Bio- and Geosciences IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, Jülich, Germany
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Schmitz F, Guo K, Horn J, Sorrentino R, Conforto G, Lamberti F, Brescia R, Drago F, Prato M, He Z, Giovanella U, Cacialli F, Schlettwein D, Meggiolaro D, Gatti T. Lanthanide-Induced Photoluminescence in Lead-Free Cs 2AgBiBr 6 Bulk Perovskite: Insights from Optical and Theoretical Investigations. J Phys Chem Lett 2020; 11:8893-8900. [PMID: 32996314 DOI: 10.1021/acs.jpclett.0c02317] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Emphasis was recently placed on the Cs2AgBiBr6 double perovskite as a possible candidate to substitute toxic lead in metal halide perovskites. However, its poor light-emissive features currently make it unsuitable for solid-state lighting. Lanthanide doping is an established strategy to implement luminescence in poorly emissive materials, with the additional advantage of fine-tuning the emission wavelength. We discuss here the impact of Eu and Yb doping on the optical properties of Cs2AgBiBr6 thin films, obtained from the solution processing of hydrothermally synthesized bulk crystalline powders, by combining experiments and density functional theory calculations. Eu(III) incorporation does not lead to the characteristic 5D0 → 7F2 emission feature at 2 eV, while only a weak trap-assisted sub-band gap radiative emission is reported. Oppositely, we demonstrate that incorporated Yb(III) leads to an intense and exclusive photoluminescence emission in the near-infrared as a result of the efficient sensitization of the lanthanide 2F5/2 → 2F7/2 transition.
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Affiliation(s)
- Fabian Schmitz
- Center for Materials Research (LaMa), Justus Liebig University, Heinrich Buff Ring 16, 35392 Giessen, Germany
- Institute of Physical Chemistry, Justus Liebig University, Heinrich Buff Ring 17, 35392 Giessen, Germany
| | - Kunping Guo
- Department of Physics and Astronomy and London Center for Nanotechnology, University College London, WC1E 6BT London, United Kingdom
| | - Jonas Horn
- Center for Materials Research (LaMa), Justus Liebig University, Heinrich Buff Ring 16, 35392 Giessen, Germany
- Institute of Applied Physics, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - Roberto Sorrentino
- Istituto CNR di Scienze e Tecnologie Chimiche "Giulio Natta", Via Corti 12, 20133 Milano, Italy
| | - Gioele Conforto
- Institute of Physical Chemistry, Justus Liebig University, Heinrich Buff Ring 17, 35392 Giessen, Germany
- Institute of Applied Physics, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - Francesco Lamberti
- Department of Chemical Sciences, University of Padova, via Marzolo 1, 35131 Padova, Italy
| | - Rosaria Brescia
- Electron Microscopy Facility, Istituto Italiano di Tecnologia, via Morego 30, 16163 Genova, Italy
| | - Filippo Drago
- Materials Characterization Facility, Istituto Italiano di Tecnologiass, via Morego 30, 16163 Genova, Italy
| | - Mirko Prato
- Materials Characterization Facility, Istituto Italiano di Tecnologiass, via Morego 30, 16163 Genova, Italy
| | - Zhubing He
- Department of Materials Science and Engineering, Shenzhen Key Laboratory of Full Spectral Solar Electricity Generation, Southern University of Science and Technology, No. 1088, Xueyuan Rd., 518055 Shenzhen, Guangdong, China
| | - Umberto Giovanella
- Istituto CNR di Scienze e Tecnologie Chimiche "Giulio Natta", Via Corti 12, 20133 Milano, Italy
| | - Franco Cacialli
- Department of Physics and Astronomy and London Center for Nanotechnology, University College London, WC1E 6BT London, United Kingdom
| | - Derck Schlettwein
- Center for Materials Research (LaMa), Justus Liebig University, Heinrich Buff Ring 16, 35392 Giessen, Germany
- Institute of Applied Physics, Justus Liebig University, Heinrich-Buff-Ring 16, 35392 Giessen, Germany
| | - Daniele Meggiolaro
- Computational Laboratory for Hybrid/Organic Photovoltaics, Istituto CNR di Scienze e Tecnologie Chimiche "Giulio Natta", Via Elce di Sotto 8, 06123 Perugia, Italy
| | - Teresa Gatti
- Center for Materials Research (LaMa), Justus Liebig University, Heinrich Buff Ring 16, 35392 Giessen, Germany
- Institute of Physical Chemistry, Justus Liebig University, Heinrich Buff Ring 17, 35392 Giessen, Germany
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Simbrunner B, Beer A, Wöran K, Schmitz F, Primas C, Wewalka M, Pinter M, Dolak W, Scheiner B, Puespoek A, Trauner M, Oberhuber G, Mandorfer M, Reiberger T. Portal hypertensive gastropathy is associated with iron deficiency anemia. Wien Klin Wochenschr 2020; 132:1-11. [PMID: 31912289 PMCID: PMC6978296 DOI: 10.1007/s00508-019-01593-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Accepted: 12/07/2019] [Indexed: 12/14/2022]
Abstract
Background and aims Portal hypertensive gastropathy (PHG) is common in patients with cirrhosis and may cause bleeding. This study systematically explored the independent impact of patient characteristics, portal hypertension and hepatic dysfunction on PHG severity and associated anemia. Methods Patients with cirrhosis undergoing endoscopy were included in this retrospective analysis and PHG was endoscopically graded as absent, mild or severe. Clinical and laboratory parameters and hepatic venous pressure gradient (HVPG) were assessed with respect to an association with severity of PHG. Results A total of 110 patients (mean age: 57 years, 69% male) with mostly alcoholic liver disease (49%) or viral hepatitis (30%) were included: 15 (13.6%) patients had no PHG, 59 (53.6%) had mild PHG, and 36 (32.7%) had severe PHG. Severe PHG was significantly associated with male sex (83.3% vs. 62.2% in no or mild PHG; p = 0.024) and higher Child-Turcotte-Pugh (CTP) stage (CTP-C: 38.9% vs. 27.0% in no or mild PHG; p = 0.030), while MELD was similar (p = 0.253). Patients with severe PHG had significantly lower hemoglobin values (11.2 ± 0.4 g/dL vs. 12.4 ± 0.2 g/dL; p = 0.008) and a higher prevalence of iron-deficiency anemia (IDA: 48.5% vs. 26.9%; p = 0.032). Interestingly, HVPG was not significantly higher in severe PHG (median 20 mm Hg) vs. mild PHG (19 mm Hg) and no PHG (18 mm Hg; p = 0.252). On multivariate analysis, CTP score (odds ratio, OR: 1.25, 95% confidence interval, CI 1.02–1.53; p = 0.033) was independently associated with severe PHG, while only a trend towards an independent association with IDA was observed (OR: 2.28, 95% CI 0.91–5.72; p = 0.078). Conclusion The CTP score but not HVPG or MELD were risk factors for severe PHG. Importantly, anemia and especially IDA are significantly more common in patients with severe PHG. Electronic supplementary material The online version of this article (10.1007/s00508-019-01593-w) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Benedikt Simbrunner
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria
| | - Andrea Beer
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | - Katharina Wöran
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | - Fabian Schmitz
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria
| | - Christian Primas
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Marlene Wewalka
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Matthias Pinter
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Liver Cancer (HCC) Study Group Vienna, Vienna, Austria
| | - Werner Dolak
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Bernhard Scheiner
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria
| | - Andreas Puespoek
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | - Michael Trauner
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
| | | | - Mattias Mandorfer
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria
- Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria
| | - Thomas Reiberger
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria.
- Vienna Hepatic Hemodynamic Laboratory, Medical University of Vienna, Vienna, Austria.
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Neves J, Vizuete A, Nicola F, Da Ré C, Rodrigues A, Schmitz F, Mestriner R, Aristimunha D, Wyse A, Netto C. Glial glutamate transporters expression, glutamate uptake, and oxidative stress in an experimental rat model of intracerebral hemorrhage. Neurochem Int 2018. [DOI: 10.1016/j.neuint.2018.03.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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13
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Tröster A, Schmitz F, Virnau P, Binder K. Equilibrium between a Droplet and Surrounding Vapor: A Discussion of Finite Size Effects. J Phys Chem B 2017; 122:3407-3417. [DOI: 10.1021/acs.jpcb.7b10392] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Andreas Tröster
- Institute of Materials Chemistry, Vienna University of Technology, Getreidemarkt 9, A-1060 Wien, Austria
| | - Fabian Schmitz
- Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudinger Weg 9, D-55099 Mainz, Germany
| | - Peter Virnau
- Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudinger Weg 9, D-55099 Mainz, Germany
| | - Kurt Binder
- Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudinger Weg 9, D-55099 Mainz, Germany
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14
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de Wolf F, Brinkman E, Weverling G, Klatser P, Kostense S, Schmitz F, Koudstaal W, Goudsmit J. COMPARISON OF BIOLOGICAL AGE ESTIMATES IN HEALTHY INDIVIDUALS: TOWARD PLASMA-BASED QUANTIFICATION. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.3219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- F. de Wolf
- Janssen Prevention Center, Leiden, Netherlands
| | - E. Brinkman
- Janssen Prevention Center, Leiden, Netherlands
| | | | - P. Klatser
- Janssen Prevention Center, Leiden, Netherlands
| | - S. Kostense
- Janssen Prevention Center, Leiden, Netherlands
| | - F. Schmitz
- Janssen Prevention Center, Leiden, Netherlands
| | | | - J. Goudsmit
- Janssen Prevention Center, Leiden, Netherlands
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15
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Minne E, Carlier P, Peters C, Mommaert C, Kennes C, Cortenbosch G, Schmitz F, Van Haesendonck M, Schrayen V, Wertelaers A. Belgian class II nuclear facilities such as irradiators and accelerators: Regulatory Body attention points and operating experience feedback. KERNTECHNIK 2016. [DOI: 10.3139/124.110722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
The aim of this paper is to present the Regulatory Body attention points and the operating experience feedback from Belgian “class IIA” facilities such as industrial and research irradiators, bulk radionuclides producers and conditioners. Reinforcement of the nuclear safety and radiation protection has been promoted by the Federal Agency for Nuclear Control (FANC) since 2009. This paper is clearly a continuation of the former paper [1] presenting the evolution in the regulatory framework relative to the creation of Bel V, the subsidiary of the FANC, and to the new “class IIA” covering heavy installations such as those mentioned above. Some lessons learnt are extracted from the operating experience feedback based on the events declared to the authorities. Even though a real willingness to meet the new safety requirements is observed among the “class IIA” licensees, promoting the safety culture, the nuclear safety and radiation protection remains an endless challenge for the Regulatory Body.
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Affiliation(s)
- E. Minne
- Bel V , Rue Walcourt, 148, B-1070 Brussels , Belgium
| | - P. Carlier
- Federal Agency for Nuclear Control , Rue Ravenstein, 36, B-1000 Brussels , Belgium
| | - C. Peters
- Bel V , Rue Walcourt, 148, B-1070 Brussels , Belgium
| | - C. Mommaert
- Bel V , Rue Walcourt, 148, B-1070 Brussels , Belgium
| | - C. Kennes
- Bel V , Rue Walcourt, 148, B-1070 Brussels , Belgium
| | | | - F. Schmitz
- Bel V , Rue Walcourt, 148, B-1070 Brussels , Belgium
| | | | - V. Schrayen
- Federal Agency for Nuclear Control , Rue Ravenstein, 36, B-1000 Brussels , Belgium
| | - A. Wertelaers
- Federal Agency for Nuclear Control , Rue Ravenstein, 36, B-1000 Brussels , Belgium
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16
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Schmitz P, Schmitz F. Emotional intelligence and coping as predictors of acculturation styles. Personality and Individual Differences 2016. [DOI: 10.1016/j.paid.2016.05.292] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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17
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Manske K, Schmitz F, Wilhelm O. Individual differences in financial decision making. Personality and Individual Differences 2016. [DOI: 10.1016/j.paid.2016.05.221] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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18
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Schmitz F, Wilhelm O. Mental speed: Structure and correlates. Personality and Individual Differences 2016. [DOI: 10.1016/j.paid.2016.05.291] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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19
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Virnau P, Schmitz F, Binder K. The ensemble switch method and related approaches to obtain interfacial free energies between coexisting phases from simulations: a brief review. Molecular Simulation 2015. [DOI: 10.1080/08927022.2015.1071810] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Affiliation(s)
- Fabian Schmitz
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 9, D-55128 Mainz, Germany
| | - Peter Virnau
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 9, D-55128 Mainz, Germany
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21
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Schmitz F, Virnau P, Binder K. Logarithmic finite-size effects on interfacial free energies: phenomenological theory and Monte Carlo studies. Phys Rev E Stat Nonlin Soft Matter Phys 2014; 90:012128. [PMID: 25122272 DOI: 10.1103/physreve.90.012128] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Indexed: 06/03/2023]
Abstract
The computation of interfacial free energies between coexisting phases (e.g., saturated vapor and liquid) by computer simulation methods is still a challenging problem due to the difficulty of an atomistic identification of an interface and interfacial fluctuations on all length scales. The approach to estimate the interfacial tension from the free-energy excess of a system with interfaces relative to corresponding single-phase systems does not suffer from the first problem but still suffers from the latter. Considering d-dimensional systems with interfacial area L(d-1) and linear dimension L(z) in the direction perpendicular to the interface, it is argued that the interfacial fluctuations cause logarithmic finite-size effects of order ln(L)/L(d-1) and order ln(L(z))/L(d-1), in addition to regular corrections (with leading-order const/L(d-1)). A phenomenological theory predicts that the prefactors of the logarithmic terms are universal (but depend on the applied boundary conditions and the considered statistical ensemble). The physical origin of these corrections are the translational entropy of the interface as a whole, "domain breathing" (coupling of interfacial fluctuations to the bulk order parameter fluctuations of the coexisting domains), and capillary waves. Using a new variant of the ensemble switch method, interfacial tensions are found from Monte Carlo simulations of d = 2 and d = 3 Ising models and a Lennard-Jones fluid. The simulation results are fully consistent with the theoretical predictions.
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Affiliation(s)
- Fabian Schmitz
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 7, D-55128 Mainz, Germany
| | - Peter Virnau
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 7, D-55128 Mainz, Germany
| | - Kurt Binder
- Institute of Physics, Johannes Gutenberg University Mainz, Staudingerweg 7, D-55128 Mainz, Germany
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22
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Schmitz F. Reinforcement sensitivity, impulsivity, and sensation seeking. Personality and Individual Differences 2014. [DOI: 10.1016/j.paid.2013.07.149] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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23
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Schmitz F, Wilhelm O. Reinforcement sensitivity, sensation seeking, and counter-productive behaviour at secondary schools. Personality and Individual Differences 2014. [DOI: 10.1016/j.paid.2013.07.153] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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24
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Schmitz F, Virnau P, Binder K. Determination of the origin and magnitude of logarithmic finite-size effects on interfacial tension: role of interfacial fluctuations and domain breathing. Phys Rev Lett 2014; 112:125701. [PMID: 24724659 DOI: 10.1103/physrevlett.112.125701] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Indexed: 06/03/2023]
Abstract
The ensemble-switch method for computing wall excess free energies of condensed matter is extended to estimate the interface free energies between coexisting phases very accurately. By this method, system geometries with linear dimensions L parallel and Lz perpendicular to the interface with various boundary conditions in the canonical or grand canonical ensemble can be studied. Using two- and three-dimensional Ising models, the nature of the occurring logarithmic finite-size corrections is studied. It is found crucial to include interfacial fluctuations due to "domain breathing."
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Affiliation(s)
- Fabian Schmitz
- Institut für Physik, Johannes Gutenberg-Universität, D-55099 Mainz, Staudinger Weg 7, Germany
| | - Peter Virnau
- Institut für Physik, Johannes Gutenberg-Universität, D-55099 Mainz, Staudinger Weg 7, Germany
| | - Kurt Binder
- Institut für Physik, Johannes Gutenberg-Universität, D-55099 Mainz, Staudinger Weg 7, Germany
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25
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Schmitz F, Virnau P, Binder K. Monte Carlo tests of nucleation concepts in the lattice gas model. Phys Rev E Stat Nonlin Soft Matter Phys 2013; 87:053302. [PMID: 23767652 DOI: 10.1103/physreve.87.053302] [Citation(s) in RCA: 17] [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] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Indexed: 06/02/2023]
Abstract
The conventional theory of homogeneous and heterogeneous nucleation in a supersaturated vapor is tested by Monte Carlo simulations of the lattice gas (Ising) model with nearest-neighbor attractive interactions on the simple cubic lattice. The theory considers the nucleation process as a slow (quasistatic) cluster (droplet) growth over a free energy barrier ΔF(*), constructed in terms of a balance of surface and bulk term of a critical droplet of radius R(*), implying that the rates of droplet growth and shrinking essentially balance each other for droplet radius R=R(*). For heterogeneous nucleation at surfaces, the barrier is reduced by a factor depending on the contact angle. Using the definition of physical clusters based on the Fortuin-Kasteleyn mapping, the time dependence of the cluster size distribution is studied for quenching experiments in the kinetic Ising model and the cluster size ℓ(*) where the cluster growth rate changes sign is estimated. These studies of nucleation kinetics are compared to studies where the relation between cluster size and supersaturation is estimated from equilibrium simulations of phase coexistence between droplet and vapor in the canonical ensemble. The chemical potential is estimated from a lattice version of the Widom particle insertion method. For large droplets it is shown that the physical clusters have a volume consistent with the estimates from the lever rule. Geometrical clusters (defined such that each site belonging to the cluster is occupied and has at least one occupied neighbor site) yield valid results only for temperatures less than 60% of the critical temperature, where the cluster shape is nonspherical. We show how the chemical potential can be used to numerically estimate ΔF(*) also for nonspherical cluster shapes.
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Affiliation(s)
- Fabian Schmitz
- Institute of Physics, Johannes Gutenberg Universität Mainz, D-55122 Mainz, Germany
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26
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Scherer EBS, Schmitz F, Vuaden FC, Savio LEB, Ferreira AGK, Tasca RAJC, Casali EA, Bogo MR, Bonan CD, Wyse ATS. Mild hyperhomocysteinemia alters extracellular adenine metabolism in rat brain. Neuroscience 2012; 223:28-34. [PMID: 22863571 DOI: 10.1016/j.neuroscience.2012.07.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Revised: 07/10/2012] [Accepted: 07/23/2012] [Indexed: 12/20/2022]
Abstract
Since homocysteine (Hcy) is considered a risk factor to cerebral diseases and adenine nucleotides are important molecules to brain normal function, in the present study we investigated the effect of chronic mild hyperhomocysteinemia on ectonucleotidase activities and expression in rat cerebral cortex. The levels of ATP, ADP, AMP and adenosine (Ado) in cerebrospinal fluid (CSF) of adult rats also were evaluated by high-performance liquid chromatography. For the chronic chemically induced mild hyperhomocysteinemia, Hcy (0.03 μmol/g of body weight) was administered subcutaneously from the 30th to the 60th day of life. Control rats received saline solution in the same volumes. Results showed that Hcy significantly decreased nucleotide hydrolysis in the synaptosomal fraction and increased E-NTPDase1 and ecto-5'-nucleotidase transcripts in rat cerebral cortex. ATP levels were significantly increased, while Ado decreased in CSF of Hcy-treated rats. These findings suggest that the unbalance in ATP and Ado levels may be, at last in part, involved in the cerebral toxicity of mild hyperhomocysteinemia.
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Affiliation(s)
- E B S Scherer
- Laboratório de Neuroproteção e Doenças Neurometabólicas, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
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Abstract
Porous metal membranes are produced from a two phase system in which the discrete cubic gamma'-precipitates connect during self assembly. In the so called rafting process the cubic particles start to coarsen and finally create a network within the gamma-matrix. In a following electrochemical leaching process one of the phases can be removed leaving the nanoporous membrane. So far, single crystalline alloys have been used for producing thin nanoporous membranes. Now research is in progress to produce the nanoporous membranes from polycrystalline alloys in a creep process. A modification of the commercially available alloy Nimonic 115 was used for these membranes. The permeability of these membranes was proven in a gas-flow test.
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Affiliation(s)
- Fabian Schmitz
- Institut für Werkstoffe, Technische Universtät Braunschweig, 38106 Braunschweig, Germany
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28
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Akat K, Kaden JJ, Schmitz F, Ewering S, Anton A, Klomfaß S, Hoffmann R, Ortlepp JR. Calcium metabolism in adults with severe aortic valve stenosis and preserved renal function. Am J Cardiol 2010; 105:862-4. [PMID: 20211333 DOI: 10.1016/j.amjcard.2009.10.065] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2009] [Revised: 10/25/2009] [Accepted: 10/25/2009] [Indexed: 10/19/2022]
Abstract
Data suggest a link of aortic stenosis (AS) with calcium and bone metabolism. To further investigate this, the following parameters were analyzed in 38 patients with severe AS and in 38 age- and gender-matched controls, without obstructive coronary artery disease and with preserved renal function: calcium, phosphate, 1,25(OH(2))-vitamin D(3), intact parathyroid hormone (iPTH), and osteoprotegerin. Patients with AS had significantly higher serum levels of calcium (2.63 +/- 0.28 vs 2.48 +/- 0.23 mmol/L, p <0.01) and phosphate (1.56 +/- 0.33 vs 1.38 +/- 0.26 mmol/L, p <0.01) and increased calcium-phosphorus products (4.16 +/- 1.13 vs 3.44 +/- 0.89 mmol/L(2), p = 0.003). Notably, the iPTH concentration in the AS group was lower, and significantly more patients in the AS group had levels less than the study median of 60 ng/L. Osteoprotegerin was elevated in patients with AS, confirming reports in other populations (9.94 +/- 5.96 vs 6.73 +/- 4.28 pmol/L, p = 0.009). The relations of several parameters to iPTH were also altered (AS vs controls): calcium and iPTH, 0.071 +/- 0.034 versus 0.046 +/- 0.023, p <0.0001; phosphate and iPTH, 0.042 +/- 0.020 versus 0.025 +/- 0.013, p <0.0001; vitamin D and iPTH, 0.99 +/- 0.61 versus 0.63 +/- 0.46, p = 0.006; and osteoprotegerin and iPTH, 0.24 +/- 0.15 versus 0.12 +/- 0.09, p <0.0001. In conclusion, these data support a hypothesis connecting (severe) AS to altered calcium and bone homeostasis.
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Shapiro K, Schmitz F, Martens S, Mueller K, Loach D, Akyurek E, Hommel B, Schnitzler A. MEG reveals correlation between task difficulty and magnitude of the attentional blink. J Vis 2010. [DOI: 10.1167/2.7.438] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Kathemann S, Pilic D, Schmitz F, Uhl W, Schmidt-Choudhury A. Raumforderung im Magenantrum. Monatsschr Kinderheilkd 2009. [DOI: 10.1007/s00112-008-1809-5] [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: 10/20/2022]
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Abstract
BACKGROUND As there are only few data on squint angle reduction following surgical treatment of unilateral abducens palsy, we aimed to quantify squint angle reduction after several different surgical procedures. PATIENTS AND METHODS Retrospective analysis of 88 consecutive files of patients with unilateral abducens palsy, treated in 2000 - 2007 (46 resections of the lateral rectus muscle, 25 resections of the lateral rectus combined with recession of the medial rectus, 17 Hummelsheim transpositions, modified by Kaufmann). Maximal abduction was possible up to primary position in all 17 patients with Hummelsheim transposition. All other patients (except two) were able to abduct beyond primary position. RESULTS In resections of the lateral rectus a stable dose-effect-correlation was found: the dose-effect coefficients (DEC) ranged between 1.5 degrees and 1.6 degrees reduction of horizontal angle (far fixation)/mm of resected muscle. In combined convergence procedures the DEC ranged from 1.52 degrees /mm (7-9 mm recession/resection) up to 1.39 degrees /mm (13-15 mm recession/resection). In muscle transpositions (Hummelsheim-Kaufmann), preoperative horizontal squint angle (far distance) was reduced from +29 degrees (median, range +15 degrees to +50 degrees ) to -3 degrees (median, range -15 degrees to +17 degrees ) postoperatively (6-8 weeks). The best results were achieved with preoperative squint angels between > +20 degrees and < +35 degrees . Larger basic angles showed mostly undercorrection; smaller angles showed always overcorrection. CONCLUSIONS Unilateral abducens palsy with maximal abduction up to primary position should be treated by muscle transposition. With squint angles (far distance) < +20 degrees a classical Hummelsheim transposition is recommended, with squint angles > +20 degrees the Kaufmann's modification should be preferred. If abduction beyond primary position is possible, lateral rectus resection suffices. With squint angles > +12 degrees additional recession of the ipsilateral medial rectus muscle becomes necessary.
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Affiliation(s)
- J Esser
- Orthoptik, Universitäts-Augenklinik Essen.
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Schmitz F, Ewering S, Zerres K, Klomfass S, Hoffmann R, Ortlepp JR. Parathyroid hormone gene variant and calcific aortic stenosis. J Heart Valve Dis 2009; 18:262-267. [PMID: 19557980] [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: 05/28/2023]
Abstract
BACKGROUND AND AIM OF THE STUDY Calcific aortic stenosis (AS) is the most frequently acquired valvular disease of the elderly in the Western world. A genetic background for AS has been proposed. The deposition of calcium hydroxyapatite is the key problem of valve calcification; vitamin D and parathyroid hormone are major factors in calcium homeostasis. The vitamin D receptor (VDR) gene and parathyroid hormone (PTH) gene variants were selected as candidate genes. METHODS A total of 538 patients with severe calcific AS (identified echocardiographically) were characterized by left heart catheterization. A group of 536 patients in whom heart disease had been excluded by left heart catheterization served as a control population. The cardiovascular risk profile was assessed, and three gene variants were analyzed, namely VDR rs1544410, VDR rs1073810, and PTH rs6254. RESULTS Patients with AS were found to have a higher prevalence of the PTH AA genotype (108 +/- 20.1% versus 71 +/- 13.2%; p = 0.007), while the VDR gene revealed a marginal, but statistically non-significant, association. The age and risk profile was similar in both groups. CONCLUSION To date, the association of the PTH gene variant has been the only positive association studied in patients with AS in a large population. Hence, the polymorphism is within an intron; the molecular mechanisms of altered gene expression should undergo further investigation.
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Affiliation(s)
- Fabian Schmitz
- Division of Cardiology, Pulmonary Diseases, and Vascular Medicine, Department of Medicine, University Hospital RWTH Aachen, Germany
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Abstract
BACKGROUND Infection with Helicobacter pylori (H. pylori) leads to the initiation of innate immune responses with increased antimicrobial peptide (AMP) expression in the gastric epithelium. This study aimed to determine the expression of the novel peptides beta-defensin 4 (hBD-4) and RNase 7 in infectious and non-infectious gastritis. Furthermore, pattern recognition receptors and mechanisms of regulation were characterized. MATERIALS AND METHODS Expression of AMPs was quantified by real-time PCR in biopsies obtained from healthy individuals and patients with infectious and non-infectious gastritis as well as in AGS gastric epithelial cells infected with H. pylori. Distribution of hBD-4 in the gastric mucosa was characterized by in-situ hybridisation and immunohistochemistry. The role of Toll-like receptors (TLRs) 2 and 4 and associated signalling pathways was addressed. RESULTS hBD-4 was expressed at low levels in gastric epithelial cells and was significantly upregulated in infectious and non-infectious gastritis. Standard eradication but not acid suppression therapy significantly decreased hBD-4 expression. Cytotoxin associated gene (cag)A positive H. pylori significantly increased the expression of hBD-4 whereas cagA negative organisms, non-viable bacteria or culture supernatants had no significant effect. Overexpression and downregulation of TLRs was not associated with an altered hBD-4 expression. However, blocking experiments revealed an essential role for the p38 mitogen-activated protein kinase. RNase7 was inconsistently expressed in biopsies and not significantly upregulated by H. pylori. CONCLUSIONS hBD-4 may play a significant role in H. pylori associated gastritis. Inconsistent expression of RNase 7 does not support a pivotal role for this peptide in response to infection with H. pylori.
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Affiliation(s)
- J-M Otte
- Ruhr-University, Bochum, Germany.
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Adamu U, Schmitz F, Becker M, Kelm M, Hoffmann R. Advanced speckle tracking echocardiography allowing a three-myocardial layer-specific analysis of deformation parameters. Eur J Echocardiogr 2008; 10:303-8. [PMID: 18801725 DOI: 10.1093/ejechocard/jen238] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
AIMS Different layers of myocardium may contribute differently to myocardial deformation. Speckle tracking based on high resolution two-dimensional (2D) echocardiography has been used to define myocardial deformation parameters of whole left ventricular (LV) segments. This study evaluated with a Novell analysis modality allowing layer-specific analysis of deformation if there are differences in myocardial deformation between different layers of myocardium. METHODS AND RESULTS In 30 normal subjects and 20 patients with impaired myocardial function 2D parasternal short-axis echocardiographic views of the LV were acquired at the basal, mid-papillary, and apical levels. Using a Novell automatic frame-to-frame tracking system of natural acoustic echocardiographic markers (EchoPAC, GE Ultrasound, Haifa, Israel), circumferential strain (CS) and strain rate of the endocardial, mid-myocardial and epicardial layer was calculated for each LV segment in an 18-segment model. Wall motion for each segment was defined as normokinetic, hypokinetic, and akinetic based on 2D echocardiographic images. Peak systolic CS could be analysed in 837 segments (93%). In the normal subjects peak systolic CS was greatest in the endocardial layer, lower in the mid-myocardial layer, and lowest in the epicardial layer (38.1+/-9.0%, 28.9+/-9.3%, and 24.0+/-9.4%, respectively, P<0.001). In the patients with impaired LV function 151 segments were hypokinetic and 92 segments akinetic by visual analysis. In all myocardial layers peak systolic CS and strain rate decreased with decreasing segmental function. CONCLUSION Decreasing myocardial deformation from endocardial to epicardial layers can be demonstrated with the use of an advanced analysis system allowing definition of deformation parameters for three myocardial layers. Myocardial deformation is reduced in all layers of segments with impaired wall motion.
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Affiliation(s)
- Umar Adamu
- Medical Clinic I, University RWTH Aachen, Pauwelsstrasse 30, 52057 Aachen, Germany
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Felderbauer P, Schnekenburger J, Lebert R, Bulut K, Parry M, Meister T, Schick V, Schmitz F, Domschke W, Schmidt WE. A novel A121T mutation in human cationic trypsinogen associated with hereditary pancreatitis: functional data indicating a loss-of-function mutation influencing the R122 trypsin cleavage site. J Med Genet 2008; 45:507-12. [DOI: 10.1136/jmg.2007.056481] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Mukherji D, Lackner J, Wanderka N, Kardjilov N, Näth O, Jäger S, Schmitz F, Rösler J. Coating of meso-porous metallic membranes with oriented channel-like fine pores by pulsed laser deposition. Nanotechnology 2008; 19:065706. [PMID: 21730712 DOI: 10.1088/0957-4484/19/6/065706] [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: 05/31/2023]
Abstract
There is increasing demand to functionalize meso- and nanoporous materials by coating and make the porous substrate biocompatible or environmentally friendly. However, coating on a meso-porous substrate poses great challenges, especially if the pore aspect ratio is high. We adopted the pulsed laser deposition (PLD) method to coat Ni(3)Al-based meso-porous membranes, which were fabricated from a single-crystal Ni-based superalloy by a unique selective phase dissolution technique. These membranes were about 250 µm thick and had channel-like pores (∼200 nm wide) with very high aspect ratio. Two different coating materials, i.e. diamond-like carbon (DLC) and titanium, were used to coat these membranes. High energy C or Ti ions, produced in the plasma plume by the PLD process, penetrated the channel-like pores and deposited coatings on the pore walls deep inside the membrane. The thickness and the quality of coatings on the pore walls were examined using the dual-beam system. The coating thickness, of the order of 50 nm, was adherent to the pore walls and was quite uniform at different depths. The carbon and the Ti deposition behaved quite similarly. The preliminary experiments showed that the PLD is an adequate method for coating fine open cavities of complex geometry. Simulations based on stopping and the range of ions in matter (SRIM) calculations helped in understanding the deposition processes on pore walls at great depths.
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Affiliation(s)
- D Mukherji
- Technische Universität Braunschweig, IfW, Langer Kamp 8, D-38106 Braunschweig, Germany
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Sebens Müerköster S, Rausch AV, Isberner A, Minkenberg J, Blaszczuk E, Witt M, Fölsch UR, Schmitz F, Schäfer H, Arlt A. The apoptosis-inducing effect of gastrin on colorectal cancer cells relates to an increased IEX-1 expression mediating NF-κB inhibition. Oncogene 2007; 27:1122-34. [PMID: 17704804 DOI: 10.1038/sj.onc.1210728] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [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: 11/09/2022]
Abstract
Addressing the puzzling role of amidated gastrin(17) (G17) and the gastrin/CCKB/CCK2 receptor in colorectal carcinogenesis, we analysed potential candidate genes involved in G17-dependent NF-kappaB inhibition and apoptosis. The colorectal carcinoma cell line Colo320 overexpressing the wild-type CCK2 receptor (Colo320wt) underwent G17-induced apoptosis along with suppressed NF-kappaB activation and decreased expression of the antiapoptotic NF-kappaB target genes cIAP1 and cIAP2, whereas G17 was without effect on Colo320 cells expressing a CCK2 receptor bearing a loss of function mutation (Colo320mut). Gene microarray analysis revealed an elevated expression of the stress response gene IEX-1 in G17-treated Colo320wt but not Colo320mut cells. Quantitative real-time PCR and conventional RT-PCR confirmed this G17-dependent increase of IEX-1 expression in Colo320wt cells. If these cells were subjected to IEX-1 knockdown by small interfering RNA transfection, the apoptosis-inducing effect of G17 was abolished. Moreover, tumor necrosis factor alpha (TNFalpha)- or 5-FU-induced apoptosis that is greatly enhanced by G17 treatment in Colo320wt cells was prevented if IEX-1 expression was repressed. Under these conditions of blocked IEX-1 expression, the NF-kappaB activity remained unaffected by G17, in particular in Colo320wt cells co-treated with TNFalpha and also the suppressive effect of G17 on cIAP1 and cIAP2 expression was not observed anymore if IEX-1 expression was blocked. Conversely, IEX-1 overexpression in Colo320mut cells caused an increase of basal and TNFalpha- or 5-FU-induced apoptosis, an effect not further triggered by G17 treatment. Using a xenograft tumor model in severe combined immune deficiency mice, we could show that experimental systemic hypergastrinemia induced by the administration of omeprazole led to enhanced apoptosis as well as to a marked increase of IEX-1 expression in Colo320wt tumors, but not in Colo320mut tumors. These observations indicate that the proapoptotic effect of G17 on human colon cancer cells expressing the wild-type CCK2 receptor is mediated by IEX-1, which modulates NF-kappaB-dependent antiapoptotic protection and thereby exerts tumor-suppressive potential.
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Affiliation(s)
- S Sebens Müerköster
- Laboratory of Molecular Gastroenterology and Hepatology, 1st Department of Medicine, University Hospital of Schleswig-Holstein, Kiel, Germany
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Kaden JJ, Reinöhl JO, Blesch B, Brueckmann M, Haghi D, Borggrefe M, Schmitz F, Klomfass S, Pillich M, Ortlepp JR. Systemic and local levels of fetuin-A in calcific aortic valve stenosis. Int J Mol Med 2007; 20:193-7. [PMID: 17611637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023] Open
Abstract
Calcific aortic valve stenosis, the most frequent heart valve disorder in developed countries, is an actively regulated process with similarities to bone formation. Fetuin-A has recently been identified as a potent circulating inhibitor of calcification. While several studies involving patients with end-stage renal disease have shown an association between low serum fetuin-A and cardiovascular calcification, nothing is known about fetuin-A serum levels in non-renal patients with calcific aortic valve stenosis. Furthermore, while fetuin-A has been localized in calcified areas of atherosclerotic arteries, data about fetuin-A deposition in stenotic aortic valves are unavailable at present. Serum fetuin-A levels were determined in patients with (n=31) and without (n=28) calcified aortic valve stenosis by ELISA. Creatinine and CRP levels were determined and glomerular filtration rate (GFR) was calculated by the MDRD formula. Immunohistochemistry for fetuin-A was performed on human calcified stenotic (n=14) and control (n=8) aortic valves using a monoclonal antibody. Serum fetuin-A levels were lower in patients with calcific aortic stenosis as compared to the control group (1.41+/-0.33 versus 1.57+/-0,27 mg/dl; p=0.046). This difference was particularly evident in individuals with a normal GFR >or=60 ml/min (1.36+/-0.24 versus 1.63+/-0.27 mg/dl; p=0.007). Furthermore, specific staining of fetuin-A was found in stenotic valves but not in healthy control valves. The data suggest a role of fetuin-A in the pathogenesis calcific aortic valve stenosis independently of the renal function and support the concept that mechanisms of calcium homeostasis are involved in the development of calcific aortic stenosis.
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Affiliation(s)
- Jens J Kaden
- First Department of Medicine, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany.
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Chromik AM, Müller AM, Körner J, Belyaev O, Holland-Letz T, Schmitz F, Herdegen T, Uhl W, Mittelkötter U. Genetic deletion of JNK1 and JNK2 aggravates the DSS-induced colitis in mice. J INVEST SURG 2007; 20:23-33. [PMID: 17365404 DOI: 10.1080/08941930601126140] [Citation(s) in RCA: 24] [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: 02/04/2023]
Abstract
The c-Jun N-terminal kinases (JNKs) are considered as novel targets for therapy of inflammatory bowel diseases (IBD). However, the relevant JNK isoforms have to be elucidated. Here, we analyze the individual contribution of the JNK1 and JNK2 isoforms in a dextran sulfate sodium (DSS) model of experimental colitis. JNK1 and JNK2 knockout mice (JNK1 ko, JNK2 ko) and their wild-type controls (WT1, WT2) received three cycles of DSS treatment, each consisting of 1.7% DSS for 5 days, followed by 5 days with water. Animals were daily evaluated by a disease activity index (DAI) comprising measurement of body weight, estimation of stool consistency, and test for occult blood/gross rectal bleeding. After 30 days all animals were sacrificed, and the inflamed intestine was histologically evaluated by a crypt damage score. Unexpectedly, neither JNK1 ko nor JNK2 ko prevented mice from developing a chronic colitis when compared to wild-type controls WT1 and WT2, respectively. On the contrary, DAI and mortality were aggravated in JNK2 ko compared to WT2. DAI and mortality did not differ between JNK1 ko and WT1, but the histological crypt damage score was significantly enhanced in the cecum of JNK1 ko mice. Genetic deletion of JNK2 worsens the disease outcome in an experimental model of murine colitis. We hypothesize that the functional deletion of the otherwise proapoptotic JNK2 prolongs the activity of proinflammatory immune cells with deterioration of disease activity.
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Affiliation(s)
- A M Chromik
- Department of General and Visceral Surgery, St. Josef Hospital, Ruhr-University of Bochum, Bochum, Germany.
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Schmitz F, Mevissen V, Krantz C, Kimmel M, Erdmann J, Hoffmann R, Zerres K, Ortlepp JR. Robust association of the APOE epsilon4 allele with premature myocardial infarction especially in patients without hypercholesterolaemia: the Aachen study. Eur J Clin Invest 2007; 37:106-8. [PMID: 17217375 DOI: 10.1111/j.1365-2362.2007.01764.x] [Citation(s) in RCA: 9] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Genetic influence on the manifestation of coronary artery disease (CAD) and myocardial infarction (MI) has been shown previously. From many candidate genes the APOE (apolipoprotein E) with the major alleles epsilon2/epsilon3/epsilon4 is in the focus of interest. MATERIALS AND METHODS In 1817 patients admitted for their first left heart catheterization at a premature age (males < 55 and females < 65) the association of APOE alleles with MI was analysed. Genotyping was done by 5' exonuclease assay (TaqMan). RESULTS APOE was significantly associated with hypercholesterolaemia (epsilon4 72% vs. epsilon3 66% vs. epsilon2 51%; P < 0.0001), and premature MI (epsilon4 57% vs. epsilon3 50% vs. epsilon2 41%; P < 0.0001; hazard ratio 1.41, 95%CI 1.14-1.75). In patients without hypercholesterolaemia, the APOE allele epsilon4 was highly predictive for the presence of premature MI (epsilon4 55% vs. epsilon3 45% vs. epsilon2 28%; P < 0.0001; hazard ratio 1.75, 95%CI 1.19-2.57). CONCLUSION The APOEepsilon4 allele shows a robust association with premature MI independent of hypercholesterolaemia.
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Affiliation(s)
- F Schmitz
- University Hospital of Aachen, Germany
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Venkataraman P, Langer G, Schmitz F, Perrakis A, Lamzin V. Remote services for model building in macromolecular crystallography. Acta Crystallogr A 2006. [DOI: 10.1107/s010876730609739x] [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: 11/11/2022] Open
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Ortlepp JR, Graf J, Vesper K, Schmitz F, Mevissen V, Sucigan S, Kersten A, Weber C, Janssens U. Relationship of five inflammatory gene polymorphisms with morbidity and mortality in 533 patients admitted to an ICU. Inflammation 2006; 29:65-71. [PMID: 16858645 DOI: 10.1007/s10753-006-9000-4] [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] [Indexed: 11/26/2022]
Abstract
BACKGROUND The aim of this study was to analyze the association of polymorphisms of five candidate genes with the outcome of consecutive patients admitted to a medical ICU. MATERIALS AND METHODS The study population was prospectively recruited. Inclusion criteria were admission to the ICU and written informed consent by the patients or their relatives. A total of 533 patients were recruited. The morbidity was assessed by SAPS II Score. Outcome data of in hospital mortality and length of ICU and hospital stay were obtained. Genotyping for genetic polymorphisms (CRP 1059, IL1B -511, CTGF -477, CCR2 64VI, IL6 -174) were performed by allele-specific fluorogenic oligonucleotide probes (TaqMan analysis). RESULTS All of the investigated polymorphisms were not associated with an altered outcome. There was no difference in morbidity and ICU or in-hospital mortality (neither in cross tabs analysis nor in Kaplan Meier or Cox regression analysis including age, gender and diagnosis as covariates) between the different genotypes. CONCLUSIONS Genotyping of the investigated polymorphism for risk stratification of patients admitted to ICU does not seem to be appropriated.
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Affiliation(s)
- Jan R Ortlepp
- Interdisciplinary Intermediate Care, University Hospital of Aachen-RTWTH, Pauwelsstrasse 30, 52057 Aachen, Germany
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Meyer zu Schwabedissen C, Mevissen V, Schmitz F, Woodruff S, Langebartels G, Rau T, Zerres K, Hoffmann R, Ortlepp JR. Obesity is associated with a slower response to initial phenprocoumon therapy whereas CYP2C9 genotypes are not. Eur J Clin Pharmacol 2006; 62:713-20. [PMID: 16847664 DOI: 10.1007/s00228-006-0158-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Accepted: 05/10/2006] [Indexed: 10/24/2022]
Abstract
BACKGROUND Initiation of phenprocoumon therapy is associated with a variable individual response. The CYP2C9 genotype has been shown to influence the response to warfarin therapy, but such an effect on phenprocoumon therapy remains uncertain. METHOD Two hundred sixty hospital patients started on phenprocoumon were recruited for this study. Body mass index (BMI), waist and hip circumference, dietary habits, comorbidity, and comedication were initially assessed. A 5' exonuclease assay (TaqManR) was used to analyze the presence of five polymorphisms of the CYP2C9 gene in each of the study patients. Study endpoints included the time necessary to achieve the international normalized ratio (INR) target (INR >2) and the total drug amount required to attain target INR. For 250 of 260 patients, the subsequent required daily maintenance dose of phenprocoumon was also recorded. RESULTS Both the necessary time and total dose required to attain target INR correlated significantly with BMI. The leaner the patient, the shorter the required time interval [BMI <22 (n=31), 5.48+/-2.49 days; BMI 22-25 (n=70), 6.09+/-2.40; BMI 25-30 (n=113), 6.76+/-3.61; BMI >30 (n=46), 8.50+/-5.75; p=0.001] and the lower the required dosage until the therapeutic range was achieved [BMI <22 (n=31), 23.8+/-12.1 mg; BMI 22-25 (n=70), 25.9+/-11.4 mg; BMI 25-30 (n=113), 29.6+/-25.2; BMI >30 (n=46), 35.8+/-19.7; p=0.027]. Overweight and waist circumference as a surrogate marker for abdominal fat were also associated significantly with these two parameters. Moreover, obesity was associated with a lower body-weight-adjusted maintenance dosage. All CYP2C9 genotypes that were tested failed to reveal an association with individual response variability. CONCLUSION Patient obesity appears to directly correspond to the amount of phenprocoumon required during initiation of therapy. The CYP2C9 genotype was not shown to influence the necessary therapeutic dosage.
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Ortlepp JR, Pillich M, Schmitz F, Mevissen V, Koos R, Weiss S, Stork L, Dronskowski R, Langebartels G, Autschbach R, Brandenburg V, Woodruff S, Kaden JJ, Hoffmann R. Lower serum calcium levels are associated with greater calcium hydroxyapatite deposition in native aortic valves of male patients with severe calcific aortic stenosis. J Heart Valve Dis 2006; 15:502-8. [PMID: 16901043] [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: 05/11/2023]
Abstract
BACKGROUND AND AIM OF THE STUDY The study aim was to evaluate the relationship between serum calcium levels and the degree of calcification found in stenotic aortic valves. METHODS Using atomic absorption spectroscopy, the hydroxyapatite content of 228 excised human stenotic aortic valves was determined and expressed as a percentage of valve mass. Left heart catheterization preceded valve replacement. In addition, serum levels of calcium and creatinine were determined before native calcific aortic valve excision. RESULTS Valves from male patients contained more hydroxyapatite than those of female patients (26 +/- 9 versus 22 +/- 9 mass%; p < 0.001). Patients presenting with lower serum calcium levels showed a slight trend towards higher levels of valve calcification (r = -0.15, p = 0.026), but this association appeared only within the subgroup of male patients. Male patients with lowest serum calcium levels displayed greatest valvular hydroxyapatite deposition (1st calcium tertiary: 29.5 +/- 8.9 mass% versus 2nd calcium tertiary 26.4 +/- 7.8 mass% versus 3rd calcium tertiary 21.4 +/- 8.9 mass%; n = 122; p = 0.001; r = -0.25; p = 0.006). This association was even more distinct in male patients with normal serum creatinine levels. Furthermore, serum calcium was inversely and significantly associated with serum C-reactive protein in male patients (r = - 0.34; p < 0.001). CONCLUSION Serum calcium levels appear to be inversely related to valve calcification in patients with severe calcific aortic stenosis (AS). This finding indicates the importance of systemic calcium metabolism in calcific AS, independent of manifest disorders of calcium metabolism or renal function. Interestingly, this association was evident only in male patients, suggesting a gender-dependent pathogenesis.
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Affiliation(s)
- Jan R Ortlepp
- Clinic for Interdisciplinary Intermediate Care and Medical Clinic I, University Hospital of Aachen, Germany.
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Bulut K, Pennartz C, Felderbauer P, Ansorge N, Banasch M, Schmitz F, Schmidt WE, Hoffmann P. Vascular endothelial growth factor (VEGF164) ameliorates intestinal epithelial injury in vitro in IEC-18 and Caco-2 monolayers via induction of TGF-beta release from epithelial cells. Scand J Gastroenterol 2006; 41:687-92. [PMID: 16716967 DOI: 10.1080/00365520500408634] [Citation(s) in RCA: 20] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE VEGF is a glycoprotein with various (e.g. angiogenic) activities. So far, research has focused on its angiogenic properties. VEGF receptors are localized on epithelial cells of patients with inflammatory bowel disease (IBD) and also on Caco-2 and IEC-18 cells. Our aim was to evaluate the role of VEGF on intestinal epithelial cell (IEC) migration and proliferation by utilizing an established in vitro model. METHODS IEC-18 and Caco-2 monolayers were wounded with a razor blade as described previously. Cells were incubated in medium w/o rat VEGF(164). After 24 h, migration was assessed by counting cells across the wound edge. Migration was blocked with neutralizing TGF-beta(1) antibodies. IEC proliferation was assessed using the MTT (3-[4, 5-Dimethylthiazol-2-yl]-2, 5-diphenyl-tetrazolium bromide) test. Semi-quantitative changes of the TGF-beta(1) mRNA expression were evaluated before and after stimulation of the cells with VEGF(164) by RT-PCR. Statistical analysis was performed with ANOVA and the Wilcoxon test. RESULTS VEGF(164) significantly induced epithelial cell migration in Caco-2 and IEC-18 cells compared to control. TGF-beta(1) antibodies completely abolished this VEGF-induced cell migration. TGF-beta(1) mRNA significantly increased in IEC-18 and Caco-2 cells after stimulation with VEGF. VEGF significantly inhibited epithelial cell proliferation in IEC-18 and in Caco-2 cells, indicating that the observed effects on cell migration were not due to any proliferate effects. CONCLUSION VEGF effects on epithelial cell migration play an important part in epithelial cell restitution by maintaining mucosal homeostasis after mucosal injury. This effect is mediated by TGF-beta(1). Our results obtain another possible role for increased VEGF levels in the intestinal mucosa of patients with IBD as reported recently by others.
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Affiliation(s)
- K Bulut
- Department of Medicine I, St. Josef-Hospital, Ruhr-University Bochum, Germany.
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Felderbauer P, Klein W, Bulut K, Ansorge N, Dekomien G, Werner I, Epplen JT, Schmitz F, Schmidt WE. Mutations in the calcium-sensing receptor: a new genetic risk factor for chronic pancreatitis? Scand J Gastroenterol 2006; 41:343-8. [PMID: 16497624 DOI: 10.1080/00365520510024214] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [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: 02/04/2023]
Abstract
OBJECTIVE In 2003 we identified a family with familial hypocalciuric hypercalcemia (FHH) (heterozygous CASR gene mutation L173P) and a mutation in the pancreatic secretory trypsin inhibitor gene (SPINK1) (N34S). While family members with an isolated calcium-sensing receptor gene (CASR) mutation remained healthy, a combination of the CASR and SPINK1 gene mutation caused chronic pancreatitis (CP). We thus speculate that the combination of two genetic defects affecting calcium homeostasis and pancreatic enzyme activation might represent a novel approach in chronic inherited pancreatic disease. We therefore sought to explore whether CASR gene mutations were prevalent in a cohort of patients with CP and confirmed SPINK1 mutations. MATERIAL AND METHODS A cohort of 19 families (n=170) with a history of idiopathic CP (ICP) was screened for mutations within the CASR gene; 104 members of that cohort had a mutation (N34S) within the SPINK1 gene and 66 of those were suffering from CP. The entire CASR gene was screened for single strand conformation polymorphism under varying polyacrylamide gel conditions and subjected to direct dideoxy nucleotide sequencing of amplified cDNA. RESULTS Single-strand conformation polymorphisms were observed in 59 samples, clustering of exons 3, 4 and 7. DNA sequence analysis revealed a yet unreported missense mutation in exon 7 (R896H) and two conservative mutations in exon 4 (F391F) and exon 7 (E790E). Furthermore, an intronic polymorphism in nucleotide position 493-19 G>A was detected in 19 out of 170 members of that cohort. CONCLUSIONS We identified three novel calcium-sensing receptor gene mutations (1 missense mutation, 2 silent mutations and 1 intronic polymorphism) in a cohort of 19 families with ICP. In particular, the kindred with the R896H mutation presenting with a similar pedigree to the family described above may indicate a role for CASR gene mutations in SPINK1-related CP. Again, only the patient with the combination of both CASR and N34S SPINK1 gene mutation developed pancreatitis, whereas in the healthy parents and children only an isolated CASR or N34S SPINK1 gene mutation could be detected. We suggest that the CASR gene is a novel yet undetected co-factor in a multifactorial genetic setting of SPINK1-related pancreatitis that alters the susceptibility for pancreatitis in these patients.
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Affiliation(s)
- P Felderbauer
- Department of Internal Medicine I, St. Josef Hospital, Ruhr-University of Bochum, Germany.
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Ortlepp JR, Krantz C, Kimmel M, von Korff A, Vesper K, Schmitz F, Mevissen V, Janssens U, Franke A, Hanrath P, Zerres K, Hoffmann R. Additive effects of the chemokine receptor 2, vitamin D receptor, interleukin-6 polymorphisms and cardiovascular risk factors on the prevalence of myocardial infarction in patients below 65 years. Int J Cardiol 2006; 105:90-5. [PMID: 16207551 DOI: 10.1016/j.ijcard.2005.03.004] [Citation(s) in RCA: 27] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2004] [Revised: 03/02/2005] [Accepted: 03/02/2005] [Indexed: 11/16/2022]
Abstract
BACKGROUND Cardiovascular risk factors (CRF) have been associated with myocardial infarction (MI), while the role of genetic risk factors (GRF) remains undetermined. METHODS Cineventriculograms of 3436 were analyzed for presence of regional function impairment as sign of MI. Genotyping for genetic polymorphism (vitamin D receptor VDR BsmI, interleukin-6 IL6-174 G/C, chemokine receptor 2 CCR2 64 V/I) was performed. CRF were assessed (hypertension, hypercholesterolemia, smoking, and diabetes mellitus). RESULTS In patients <65 years (n=1946) genotypes (VDR BB, IL6 GC/CC, CCR2 VI/II, defined as GRF) were significantly associated with the presence of MI (BB: OR 1.38, 95%CI 1.07-1.79, p=0.016 GC/CC: 1.28, 95%CI 1.03-1.60, p=0.028 VI/II: 1.49, 95%CI 1.17-1.88, p=0.001). Combining four CRF (14% vs. 21% vs. 27% vs. 31% vs. 38%, p<0.0001) and three GRF (21% vs. 25% vs. 32% vs. 44%, p<0.0001) revealed additive effects on the prevalence of MI. The more combined CRF and GRF were present (from 0 to 7) the higher was the prevalence of MI (11% vs. 12% vs. 21% vs. 27% vs. 30% vs. 34% vs. 59%, p< 0.0001). Age was not associated with MI. In patients > or =65 years (n=1490) the combination of CRF was only weakly associated with MI, while GRF were not. In these patients age was a predictor of MI. CONCLUSION Certain GRF might have additive but small effects on the disposition for MI before the age of 65. In older patients the tested GRF had no effect, possibly indicating a mechanism of aging rather than a purely genetic determined entity. Given the small effect of the tested genetic polymorphisms the value of testing GRF remains uncertain.
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Affiliation(s)
- Jan R Ortlepp
- Medical Clinic I, University Hospital of Aachen, Pauwelsstrasse 30, 52057 Aachen, Germany.
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Laïque S, Egrise D, Monclus M, Schmitz F, Garcia C, Lemaire C, Luxen A, Goldman S. L-Amino acid load to enhance PET differentiation between tumor and inflammation: anin vitro study on18F-FET uptake. Contrast Media Mol Imaging 2006; 1:212-20. [PMID: 17193698 DOI: 10.1002/cmmi.107] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Labeled amino acids (AA) are tumor tracers for use in nuclear medecine. O-(2-[(18)F]fluoroethyl)-L-tyrosine (FET) is transported by the L-system, known to function as an exchanger. In vitro utilization of FET, after a preload or prior to an afterload of non radioactive L-amino acids, was evaluated in order to measure the potential effects of AA content on the distinction between tumor and inflammatory lesions. Cellular uptake of FET was studied on rat osteosarcoma cells (ROS 17/2.8) and human leukocytes, initially loaded with nonradioactive L-tyrosine or L-methionine. FET efflux was evaluated from cells loaded with nonradioactive L-phenylalanine after tracer uptake. ROS 17/2.8 showed a higher sensitivity to preload and afterload effects on cellular FET content as compared with the leukocytes. We conclude that preload with L-tyrosine, prior to the administration of FET, may be a potential procedure to improve PET differentiation between tumor and inflammatory lesions.
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Affiliation(s)
- S Laïque
- PET/Biomedical Cyclotron Unit and Department of Nuclear Medicine, ULB-Hôpital Erasme, 808 route de Lennik, 1070 Brussels, Belgium.
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Mukherji D, Pigozzi G, Schmitz F, Näth O, Rösler J, Kostorz G. Nano-structured materials produced from simple metallic alloys by phase separation. Nanotechnology 2005; 16:2176-2187. [PMID: 20817992 DOI: 10.1088/0957-4484/16/10/034] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A method which is able to produce different types of nano-structured materials, namely nano-particles, nano-structured surfaces and nano-porous membranes, from two-phase metallic alloys is reviewed. The new process first establishes nano-structures in the bulk alloy and then separates them by selective phase dissolution. Variation in processing makes it possible to produce different types of nano-structure even from the same alloy. The process can be applied to many different alloy systems. An overview is presented emphasizing the versatility of the process with examples of different nano-structure types that can be produced. Further, the new method is discussed in relation to similar processes (specifically, electrochemical processes) which have been used for nano-structure synthesis.
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Affiliation(s)
- D Mukherji
- ETH Zurich, Institute of Applied Physics, CH-8093 Zurich, Switzerland
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Felderbauer P, Hoffmann P, Klein W, Bulut K, Ansorge N, Epplen JT, Schmitz F, Schmidt WE. Identification of a Novel Calcium-Sensing Receptor Gene Mutation Causing Familial Hypocalciuric Hypercalcemia by Single-Strand Conformation Polymorphism Analysis. Exp Clin Endocrinol Diabetes 2005; 113:31-4. [PMID: 15662592 DOI: 10.1055/s-2004-830523] [Citation(s) in RCA: 8] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Calcium-sensing receptor gene (CASR) mutations that alter the function of the G protein coupled Ca (2+)-sensing receptor are reported in patients with familial hypocalciuric hypercalcemia (FHH), autosomal dominant hypocalcemia (ADH), and neonatal severe hyperparathyroidism (NSHPT). In search for novel disease causing mutations in the CASR gene, we screened exons 2 - 7 of the CASR gene of a family with FHH using single-strand conformation polymorphism analysis. We identified a novel CASR mutation (c.518 T > C; L173 P) in exon 4 encoding for the extracellular domain of the Ca (2+)-sensing receptor. This region seems to represent a hot spot within the CASR gene with at least 13 reported disease causing mutations thus far.
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Affiliation(s)
- P Felderbauer
- Department of Internal Medicine I, St. Josef Hospital, Ruhr-University of Bochum, Germany.
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